My 2024 4AGE 16v build

[ImpactEighty]

First and foremost, introductions.

Hey club4ag. This will be my first ever post here on this forum. I hope all of you are doing well for the holidays and hope you all had a great 2023! As the topic suggests, I am planning out a 4AGE build for my 1987 AW11 and I couldn’t be more stoked to get started on it.

(If my photos weren’t so big I could’ve shown the car )

I had made a rough draft of things I wanted done for the build that I think would allow me to hit my goals. But before I list the things I wanted done, I will list the goals I want to hit, and the budget I want to stay within to see if the possibility of “less is more” is a viable option.


Key things to note for my 2024 4AGE 16v build:

150HP Goal

Naturally Aspirated

8000 RPM wanted (not needed but I like them beans)

Stay on 91 pump gas

3500-4000 $ budget

Keep TVIS system and EGR (I live in beloved California )

4AGZE exhaust system or custom setup if I have room in the budget for it.

Now here is the rough draft of what I want done to hit my goals. This is also going to be an entirely different motor to be built so the current 4AGE in the MR2 is staying in the car until this motor gets finished ready to drop in.

Cylinder Head

Head Core - Bigport 16v

Valves - MRP Stainless Steel +0.5mm OS

Guides - OEM Valve Guides

Valve Springs - Toda Valve Springs

Bucket Type - OEM Buckets & Shims

Stem Seals - Supertech Stem Seals

Valve Seat Cutting - Radius Cut +0.5mm

Head Stud Hole Size - OEM

Camshaft - Tomei Poncam/Procam
Cam Gears - Hasselgren Adjustable Cam Gears

Engine Block

I am currently looking for a machine shop in SoCal that has a good reputation with working on 4AGE engines. If anyone has had a good experience with any shops in SoCal primary in the IE or OC area I’d greatly appreciate it.

(.5mm Oversized Bore. 81.5 total diameter)
Pistons: Bigport or Smallport Pistons
(Use BP 9.4:1 or SP 10.3:1 Pistons .5mm oversized)
Headgasket: TRD or Cometic
(Gasket thickness is TBD)
Connecting Rods: Maxpeeding Rods
Crankshaft: depends on what type to block I can get my hands on.
Head Bolt type: ARP Head Studs
(OEM Sizing)

I’m going to start building the motor when I obtain the block and crank. I’m looking for a 7rib 4A block with oil squirters. Idk how hard it is to find that specific block but I am WTB one in good condition if possible.

Injector sizing, Ignition, and possibly Standalone choice will be up in the air as I get suggestions and do more research.

[ImpactEighty]

The chassis itself will get some real goodies in the suspension department. Bob Pham’s 808 coilovers will be poison of choice with Poly bushings.

For wheels and tires I’m going for Kansei KNP 15x7 +25 rims, and a good tire that is 195/50r15. If I can’t find anything in that size I will one up to 205/50r15.

Corbeau GTS II seats for driver and passenger.

Momo steering wheel. No quick release

I saw a video of a guy using an SW20 shift lever and bushing for a short throw shifter “retrofit” plus a few other threads on the MR2OC forum talking about it. I thought that’d be awesome to do.

Toda Racing Flywheel with ACT stage 2 clutch kit. C52 transmission that is freshly rebuilt with an LSD. I have no clue where to find an LSD for this car but I am searching. And if it’s even worth doing, MRP’s close ratio gear kit? I have yet to hear anything about them and im on the fence to even consider it at all

Along with a few other things I can’t name off the top of my head at the moment but I will edit the post when I get to remembering!

Please help me figure out adding pictures. My photos are too big in size to be added

[sirdeuce]

What is your intended use for this car?

If you haven't gotten a block yet I would say look for the early 40mm rod journal crank and pop on a 9lb flywheel for a lively engine. Or, if you are a bit more adventurous, look into a 7AGE build.

8,000rpm is doable if you get a stand alone ECU, the stocker isn't very user friendly for such mods, it's pretty much set in stone. If you want to try it, and are good with doing any tuning with the stock ECU, you can get the crustal changed and crank it up to about 8,500rpm. I've done it without issue, but it's pretty well frowned upon by most.

Being from Cali myself, and dealing with the smog Nazis here, the stock exhaust manifold is the way to go, but there are things you can do. Match port the exhaust ports to the manifold, and if you have the nerve, have a custom downpipe built that is a size bigger in diameter made and open the manifold up to match Nd kick in a 2 1/4" exhaust and cat.

Why not go for the whole mm larger vales? The stock seats are fine with that oversize. The intake really only needs pocket porting at the level you are looking at, but do a full port job on the exhaust.

Most here would tell you to go to a comp ratio as high as 11-1, but if you have to do the dyno test for smog you take the chance of blowing your NO through the roof. And your cam choice can get you failed by an overzealous technician. I've had it easy enough with cams in the 215 degree at .050" lift range. Currently have real mild cams in with WEB Cams 294 grind (244 ad. duration) on the exhaust and a PONCAMS 258 degree on the intake, tptally stock 4AGE engine otherwise. ( 7AGE is in pieces currently)Combo does well enough for around town.

For an MR2, I say a torque biasing LSD would be the best choice, unless you plan to drift the thing.

Note on a 7AGE build. The crank is an 85.5mm stroke, the 4AGE is 77mm. The crank is heavier and the stroke makes it seem a bit sluggish, but the increase in torque more than makes up for it. Consider that doing just the bare bones necessity changes to put the 4AGE head on a 7AFE block will net you 120 ftlb torque and 120hp with the torque peaking about a 700rpm earlier and the hp about 500rpm earlier than the 4AGE it kinda loses the rev happy feel, but it'll knock the 4AGE around all day.

Have fun with the build! So many possibilities.

[jondee86]

Please help me figure out adding pictures. My photos are too big in size to be added

To posts pics you need to resize them so that the maximum dimension is 1280 or less
(or whatever max size this site says) and then upload them to an image hosting site.
Copy the link provided by the hosting site and paste it into your your post and add the
tags [img]and[/img] around the link.... so, [img]yourlinkhere.jpg[/img] making sure
you use square brackets. Then preview to see what you got

Cheers... jondee86

[ImpactEighty]

What is your intended use for this car?

The intended use is honestly everywhere. I want to daily it, track it, go on some long distance trips in it if I’m up for it, and just having a blast in something I made that I would consider a “tame” 4AGE build

Or, if you are a bit more adventurous, look into a 7AGE build.

[/quote]
I did think about a 7AGE and debated on if I should build one of those up instead considering 4A blocks and cranks are getting harder to find in good condition especially in SoCal. If I can get better results for less doing a 7AGE than a 4AGE then sign me up!

Currently have real mild cams in with WEB Cams 294 grind (244 ad. duration) on the exhaust and a PONCAMS 258 degree on the intake, tptally stock 4AGE engine otherwise. ( 7AGE is in pieces currently)Combo does well enough for around town.

running two different camshafts is worth it on these kinds of engines? Interesting..

What I gathered so far upon doing my own little quick research and what you’ve explained to me (thank you by the way) I think I might be able to get more for less than I was thinking of doing. I will update the thread soon to show the revisions

[sirdeuce]

Building an engine to be an "everywhere" engine can be a bit of a challenge, especially when "tracking" is added to the mix. Even a tame engine can be stessed to the point of falling apart when tracked.

You'll get 12 different suggestions on what direction to go with your build, but here's a few considerations.

Mild build, keeping in mind you have to smog the thing in Cali, The bigger the cam the harder passing the test will be, especially with the stock ECU. When you start getting in the "260+" degree cams the idle gets choppy and the tech can fail you on that alone. Idle HC tends to climb at that level cam as well, and with unburned fuel the CO gets up there as well.

If you are in an "enhanced" area having a high compression ratio will push your NO emissions over the limit.

Port work can send the stock ECU into fits. Be careful here. Mild port work, intake port matching and minor bowl work won't bother the stock ECU, exhaust port can be worked a bit more. Slightly larger valve will be fine. Full on Atlantic set-up won't work.

Stand alone ECU, if the tech looks, FAILS. If the tech doesn't look at the little black box and you mock up all the sensors you delete for the stand-alone the extra vacuum line for the MAP sensor can lead 'em to it.

Just a few speedbumps I've rolled over.

[sirdeuce]

The 4AGE is really a stout engine, Toyota and Yamaha did a fantastic job of designing a machine that can take a licking. You have options with what block and crank set you use, and even 2 different cylinder heads.

If you want to build a reliable, long life 4AGE, that you intend to play with, pay attention to the oiling system. Starvation and overheated oil will kill your engine faster than anything else.Get the best volume pump, late model 4AGE. Smooth the pump's oil galleys, and if you can, get the housing hard anodized and lap the gears into the pump body. Baffle the pan, maybe increase the volume. Increase oil return from the head to the pan. Add an oil cooler, don't put it in the factory cooler lines, needs to be in the pressure side. You can keep the stock cooler and the bypass, it cools the oil in the pan.

Pistons. Go with Hypereutic pistons for the best longevity. The tighter clearances reduce wear and the cost is lower. If you go with forged pistons get a 4032 alloy, the clearances are tighter than the 2017 and will be longer lasting on the street. The hyper pistons are somewhere between forged and cast for strength and can take a fair amount of abuse.If you get hyper pistons the dry film coatins on the skirts are good, but don't ceramic coat the crowns, they actually do better with the heat in the top of the pistons. Pay attention to the top ring gap as well, hyper pistons run HOT and the ring gap has to be wider.

Block? 7 rib, hands down. If your budget allows a good crank girdle helps with any level of build.

Crank? The late 42mm rod pin has more surface area in the bearing and is the preffered choice, but that is mostly for the guys that get crazier in their builds. For my street builds I like to use the early crank with the 40mm rod pins. OST has recommended a set of "Molnar" rods that have a big end for the 40mm crank that has the late 20mm wrist/gudgeon so you can have a full float piston pin instead of the press fit 18mm pin used with the early rods. The early crank is lighter and make for a more lively engine. the early crank is just as reliable as the late until you get crazy.

Cams are what give your engine it's personality. If you have the time and resouces you can change duration and lift to fine tune the torque curve. Add a set of adjustible cam sprockets and the flexibility gets broader. Best you can do is look at what others have done and try it with your engine. The ports also need to be considered when choosing the cams. Stock ports will support mild cams, at the top of the "260+" duration class cams stock ports tend to be detrimental to their effects.

Head. For the best all-around head the small port is the king, but if you have to pass the CA smog test you might have issues, no T-vis. The big port head has the T-vis and will pass the visual.

[sirdeuce]

Advantages of building the 7AGE.

You get 8.5mm more stroke! The longer stroke will give you more torque and improved economy. The USDM 4AGE is rated at 98ftlbs of torque at (I think) 4300rpm and 112hp at (I think) 6600rpm. Building a 7AGE with the minimum steps necessary, head, pistons, crank timing sprocket, and the fitment mods, you can expect @120ftlbs of torque 300rpm lower in the curve and @120hp 300rpm lower in the curve.

For a mild build the stock ECU is sufficient, the AFM helps a lot in that matter.

The 7A passes the visual without issue, the techs never look at the block number. Any level build with a 4AGE that passes the sniffer test passes better with the 7AGE.

Around town driveability is easier since the torque allows less throttle off the line and while cruising. The car is more mild mannered. With the extra torque off the line acceleration is improved as well. On long trips, I do a lot of long distance highway driving, I got about 37mpg with a bit more than a mild built engine. For track days you'll have pretty much the same top speed, but you'll get there faster and your corner exits will be faster.

The extras needed to get to the 7AGE are a timing belt with 115-116 teeth. The 116 tooth belt is easiest to access and comes from a Porsche 924 engine, it's a tad long and is at the tensioner limit when used. The 115 tooth come from a Euro Renault and can be a bitch to source. The carank sprocket has to be reclocked from the 4AGE marks, cam timing will never be right without it, you can use adjustible cam sprockets, but that limits your ability to adjust the cams for tuning.
To use the stock exhaust manifold, since the head is raised and causes clearance issues, the starter should be moved to the intake side of the engine and the down pipe needs to be modified or fabbed to clear the 7A oil pan. The TRD headers will clear the pan, and are the only headers with a C.A.R.B. E.O. for the MR2. Really best to go with the stock manifold though. MRP does have a pan adapter plate that allows the use of the 4AGE pan that gives more clearance and supposedly relieves the necessity to lengthen the downpipe. MRP's girdle also adapts the pan, cost is up there though.
Moving the starter is easy enough, all you need is the backing plate and starter from a late 4AFE or 7AFE from a Corolla or Celica, and a little wire reroute.

When using the 4AGE oil pump pay attention to the pump/block galley interface, it's offset. not a big deal to match the holes. use a late 4AFE oil pump gasket.

To regain that lively 4AGE feel a light flywheel helps.

Added cost is the block, the crank sprocket, maybe a set of rods (recomended), starter and backing plate, and downpipe mods.The rest is just what you would do for building a 4AGE.

There are 3 schools out there on the subject, the 4AGE only guys that don't think the 7AGE is not worth the effort, the 7AGE guys that wouldn't have it any other way, and the "just swap in a different engine" guys. At the risk of becoming a Club4AGE pariah I will admit the Honda K swap sounds like the way to go! But I will keep my 7AGE.

[ImpactEighty]

Get the best volume pump, late model 4AGE. Smooth the pump's oil galleys, and if you can, get the housing hard anodized and lap the gears into the pump body.

Would the ST/BT oil pumps be considered the late model pumps? Which is better to use for a 7A? You inspired me to make a 7A which loops me back to my VERY VERY first setup plan which is fairly similar build to what I’m planning to do here but just 7A.

Baffle the pan, maybe increase the volume. Increase oil return from the head to the pan.

I can get the baffled pan and sump spacer from MRP and call it there. But how would I increase oil return? That’s something I have to do more research on for future builds.

Add an oil cooler, don't put it in the factory cooler lines, needs to be in the pressure side. You can keep the stock cooler and the bypass, it cools the oil in the pan.

What oil cooler would you recommend? Is the thermostatic kit that MRP also makes a useful item to have?

Go with Hypereutic pistons for the best longevity. The tighter clearances reduce wear and the cost is lower.

Are the GZE pistons considered hypereutic? I want to stay on pump gas so I don’t have to worry about finding a specific station OR too high of a CR to pass smog. I did the research and found that the 7A with GZE pistons and .8mm HG gets around 9.8CR if I read the CR table made by SQ Engineering back in 2018. (I hope this info is correct)

If you go with forged pistons get a 4032 alloy, the clearances are tighter than the 2017 and will be longer lasting on the street. The hyper pistons are somewhere between forged and cast for strength and can take a fair amount of abuse.If you get hyper pistons the dry film coatins on the skirts are good, but don't ceramic coat the crowns, they actually do better with the heat in the top of the pistons. Pay attention to the top ring gap as well, hyper pistons run HOT and the ring gap has to be wider.

I’m super torn now between if I should run forged or GZE pistons.. this is all REALLY good info and I greatly appreciate all of it!

Block? 7 rib, hands down. If your budget allows a good crank girdle helps with any level of build.

All 7AFE block aren’t 7 rib? That I didn’t know until now thanks for that. Would oil squirters give any sort of advantage? It’s not on the priority list but I am curious on if they would be good to have.

Crank? The late 42mm rod pin has more surface area in the bearing and is the preffered choice, but that is mostly for the guys that get crazier in their builds. For my street builds I like to use the early crank with the 40mm rod pins. OST has recommended a set of "Molnar" rods that have a big end for the 40mm crank that has the late 20mm wrist/gudgeon so you can have a full float piston pin instead of the press fit 18mm pin used with the early rods. The early crank is lighter and make for a more lively engine. the early crank is just as reliable as the late until you get crazy.

So these Molnar rods can bridge the problem with the 40mm and the 42mm crankshafts? Nice. I’d definitely look into those for the build. Any idea what the part number is for them?

Cams are what give your engine it's personality. If you have the time and resouces you can change duration and lift to fine tune the torque curve. Add a set of adjustible cam sprockets and the flexibility gets broader.

what can gears do you run if you use them. I’d plan to use the Hasselgren ones as I think those look really nice. Don’t know about their performance at all but it’s worth trying right?

Best you can do is look at what others have done and try it with your engine. The ports also need to be considered when choosing the cams. Stock ports will support mild cams, at the top of the "260+" duration class cams stock ports tend to be detrimental to their effects.

I will do more research on best cams for 7A thanks for pointing this out!

Head. For the best all-around head the small port is the king, but if you have to pass the CA smog test you might have issues, no T-vis. The big port head has the T-vis and will pass the visual.

Would the adapter to allow TVIS on smallport be a good workaround to this problem? If so I’d be more than willing to keep the TVIS on a smallport. I had seen some dyno pulls done with a similar combo by 4AG Garage. He’s really good at doing any and all combinations of the 4A

[sirdeuce]

Late model 4AGE oil pumps are good, the ST is the same, but the BT has a different tensioner set-up so it's esier to source the high comp and ST pumps.

Increasing the volume on a oil pan is just increasing the size of the sump, easy enough to do when baffling the stock pan. I wouldn't put more into a street/weekend warrior engine. Still your choice though.

Thermo bypass isn't really necessary, but it helps in cold climates. Just another leak waiting to happen. For an oil cooler, don't get the fin-on-tube style radiator, get a plate type, and not the ebay or Temu special.

GZE pistons are in a class by themselves. The material is hyperutectic, high silicon content, but the casting process is different than regular casting, it's done at high pressure and is called "semi-forged". Falls somewhere between hyper piston strength and forged strength an is lighter than cast or forged.Compression ratio with JDM GZ pistons is 9-1. With all else remaining stock those pistons should land at @ 10.5 - 1. If you are building an N/A engine I would look for pistons that aren't dished, like the GZ pistons so a proper quench are can be maintained. Look for flat top pistons.

Oil squirters can be installed in the 7A block if you want, but all that is really needed is a Cosworth notch in the thrust are of the con rod. Get someone to do it right either way. With hyperutectic pistons cooling the piston body kinda reduces the effective operation of the metal. Squiters help with cast or forged pistons.

3 rib = early 4A block
7 rib = late 4A block
7a is a monster all on it's own.
Either block benefits from a girdle.

Those Molnar rods allow the use of full float 20mm pins on the earlier 40mm crank. Figure what way you want to go before you consider any parts. If you shoot for a 7AGE you'll need rods for a 7A.

Adjustible cam gears are like religion, it's a matter of prefernce. I have a set of HKS, my AE82 left with a set of AEM and I have a set of "antique" TRD sprockets on the shelf with my other museum pieces. I know a few Honda guys running with ebay sprockets and are happy with them.

Where you go with cams is where you want your power band. be sure to match the ports with the cams.

"Adapters" and "spacers" are a red flab to the smog tech, just go with the big port and possibly save youself a headache.

[sirdeuce]

Honestly, I believe the 7AGE would be a better choice. If you have a goal of merely 150hp and would like driveability and longevity while being able to pass the local emissions tests, the 7AGE should make you happy. The longer stroke would help with the dyno part of the test if you're in an "enhanced" test area. They really don't understand how engines work, expect a little 1.6 liter engine to operate within the same power band as a massive V8, dumbest thing I've heard them defend when I talk to them. Stupid people! Anyway, the higher torque peak lower in the RPM range helps counter that dyno load that I've seen many times bog the crap out of my 4AGE.

Pre OBD2 cars should be exempt from the smog program.

[ImpactEighty]

You get 8.5mm more stroke! The longer stroke will give you more torque and improved economy. The USDM 4AGE is rated at 98ftlbs of torque at (I think) 4300rpm and 112hp at (I think) 6600rpm. Building a 7AGE with the minimum steps necessary, head, pistons, crank timing sprocket, and the fitment mods, you can expect @120ftlbs of torque 300rpm lower in the curve and @120hp 300rpm lower in the curve.

Does that mean that I won’t be able to rev it to 7.5k like a normal 4A?

For a mild build the stock ECU is sufficient, the AFM helps a lot in that matter.

Stock ECU all the way! Might want to do standalone one of these days after the fact and have COP setup instead of the distributor setup.

The 7A passes the visual without issue, the techs never look at the block number. Any level build with a 4AGE that passes the sniffer test passes better with the 7AGE.

This is super good to know! Glad to know that 7A engines can live legally in Cali.

Around town driveability is easier since the torque allows less throttle off the line and while cruising. The car is more mild mannered. With the extra torque off the line acceleration is improved as well. On long trips, I do a lot of long distance highway driving, I got about 37mpg with a bit more than a mild built engine. For track days you'll have pretty much the same top speed, but you'll get there faster and your corner exits will be faster.

This is what I had in mind when wanting to build this motor! Yes I added the track portion but I’m only gonna go when I actually have a reason or time to. Definitely going to want a daily street build that can handle road trips every so often. Track days will be done sparingly or when I have the money for tires and wanna roll the dice on a mechanical failure

The extras needed to get to the 7AGE are a timing belt with 115-116 teeth. The 116 tooth belt is easiest to access and comes from a Porsche 924 engine, it's a tad long and is at the tensioner limit when used. The 115 tooth come from a Euro Renault and can be a bitch to source. The carank sprocket has to be reclocked from the 4AGE marks, cam timing will never be right without it, you can use adjustible cam sprockets, but that limits your ability to adjust the cams for tuning.

So if I use the reclocked sprocket with adjustable cam gears AND a long timing belt would I be able to time it more accurately? Or at least to where I want it to be? I’m learning as I go for this build but not as I’m doing the work. I want to know prior to any purchase.

To use the stock exhaust manifold, since the head is raised and causes clearance issues, the starter should be moved to the intake side of the engine and the down pipe needs to be modified or fabbed to clear the 7A oil pan.

would any exhaust shop be able to do something like this?

Really best to go with the stock manifold though. MRP does have a pan adapter plate that allows the use of the 4AGE pan that gives more clearance and supposedly relieves the necessity to lengthen the downpipe. MRP's girdle also adapts the pan, cost is up there though. Moving the starter is easy enough, all you need is the backing plate and starter from a late 4AFE or 7AFE from a Corolla or Celica, and a little wire reroute.

Another piece to add to the parts list! I’ll look for it soon

When using the 4AGE oil pump pay attention to the pump/block galley interface, it's offset. not a big deal to match the holes. use a late 4AFE oil pump gasket.

To regain that lively 4AGE feel a light flywheel helps.

Does a TODA flywheel for a 4AGE work? I already have one of these installed on the original motor.

Added cost is the block, the crank sprocket, maybe a set of rods (recomended)

are Maxpeeding rods good to use? Or are MRP the way?

Sorry for the super late reply I’ve been working my ass off recently but I’m here!

[sirdeuce]

I've used Maxspeeding rods without issue. I've used the stock 7A rods without issue. The stock rods are actually stronger than would be expected, just prefer not using the press fit wrist pins. The "H" beam rods are indeed stronger and lighter.

Flywheel is different between 4AGE and 7AFE as the bolt patterrn for the 4A is an 8 bolt and the 7A is 6 bolts. Both have the same starter ring gear. Light flywheels are arailable for the 7A.

Any exhaust guy worth their salt can do the exhaust mods.

Revving the 7AGE? Hmmm. That's been a bit of an arguement between the 4 and 7 AGE peeps. The 7A with a stock flywheel is heavier than the 4A and won't be as rev happy as the 4AGE. A light flywheel restores that zippy feeling.
As for th "A 7AGE won't rev" thing, That is typically from not having the proper cam timing. When the 7AGE builds started only a few were built properly and people thought they just wouldn't rev. You'll hear that it's because of the longer stroke and that's what slows the engine down. Not the stroke Bubbuh, the 2ZZ is basically the same engine as the 7AGE with an 82mm bore and an 85mm stroke. That engine revs to 8500rpm all day long.
Properly built and tuned the 7AGE will act like a 4AGE with more torque.

[ImpactEighty]

I've used Maxspeeding rods without issue. I've used the stock 7A rods without issue. The stock rods are actually stronger than would be expected, just prefer not using the press fit wrist pins. The "H" beam rods are indeed stronger and lighter.

So would the stock rods be more beneficial to what I want kind of 7A I want to build? I do see that the MRP 7A conversion kit comes with their H-beam rods already so I might as well use what I pay for. Easy!

Flywheel is different between 4AGE and 7AFE as the bolt pattern for the 4A is an 8 bolt and the 7A is 6 bolts. Both have the same starter ring gear. Light flywheels are available for the 7A.

I see that MRP has an actual 7AGE oriented flywheel I personally think that would be what I go for when it comes down to it.

Properly built and tuned the 7AGE will act like a 4AGE with more torque.

You are very VERY knowledgeable about this frankenstein platform for the 4A and that's awesome I greatly appreciate any and all info that I can get my hands on. Especially the "getting my hands dirty" portion of it all and it makes the project feel less intimidating.

I will 100% ask for any help or advice I would need when I cross those bridges. But for now I have to collect parts and be patient.

ALSO could you send me a build list of your 7AGE? Im interested to see hwo yours was built up considering you're also in California. Might take a few notes too

[sirdeuce]

Where in Cali are you? Townwise.

[ImpactEighty]

Where in Cali are you? Townwise.

riverside

[sirdeuce]

I'm in Atascadero, just north of San Luis Obispo.

[ImpactEighty]

I'm in Atascadero, just north of San Luis Obispo.

Oh dang you’re a good ways away from me! Does it get warm out there?

[sirdeuce]

I've experienced temps ranging from 115 F down to 8 F.

[oldeskewltoy]

Not sure why I haven't seen this thread before.........

If your budget is correct, "3500-4000 $ budget" you will be tough pressed to build much. A 7AG would add a bit more as well. I'd recommend you start listing the costs of all you have mentioned, add in rebuilding parts (bearings, pumps, gaskets, and seals), and machine shop costs. If you are building a 7A version, add in the cost to acquire the short block. The money adds up quickly.

You mention 150hp... it might be possible to build an emissions compliant 150 flywheel hp, 150 wheel horsepower is out of the question, even with a 7A block.

efficiency is the answer to both more power, and emissions compliance, you want to try and match compression ratio, and camshaft duration. Stock USA ECU has a rev cut @7500 rpm, so using a camshaft that makes peak power at 8000+ is inefficient. Also inefficient - not running enough compression with too much cam duration.

As far as head work, you can run a radiused seat on the exhaust side, but a more traditional 3 angle, plus back cutting the intake valves works a bit better then a radiused cut intake. +.5mm valve will add some, but a properly ported head using stock valves will flow nearly the same, and save you $$ on the valves.

For cams, I'd run something a bit "smaller" then the Poncams, Cat cams 244 cam has less duration, and works well within the OEM ECU parameters. I also know a set has passed Cally emissions.

Bigport pistons are fine for building a stock 112-115hp, if you want more you will need more compression. Smallport pistons work quite well in bumping power.

As the engine is going to be transverse, you don't really need the extra head oil drain, but an HKS style oil resstrictor can be useful, along with the MR2 baffle kit - it fits best to OEM Toyota oil pans. Oh, and a real thermostatically controlled oil cooler.



That's a start.........

[sirdeuce]

Were we supposed to be talking about wheel output?

[ImpactEighty]

You mention 150hp... it might be possible to build an emissions compliant 150 flywheel hp, 150 wheel horsepower is out of the question, even with a 7A block.

I meant it as brake horsepower. However if getting to 150bhp is harder than getting to 150fhp NA, lowering the power expectation is fine by me!

If your budget is correct, "3500-4000 $ budget" you will be tough pressed to build much. A 7AG would add a bit more as well. I'd recommend you start listing the costs of all you have mentioned, add in rebuilding parts (bearings, pumps, gaskets, and seals), and machine shop costs. If you are building a 7A version, add in the cost to acquire the short block. The money adds up quickly.

I had already made a list for both builds and the parts needed to make it happen. I still have no idea on a decent machine shop in my area that will work with 7AG or 4A builds.

efficiency is the answer to both more power, and emissions compliance, you want to try and match compression ratio, and camshaft duration. Stock USA ECU has a rev cut @7500 rpm, so using a camshaft that makes peak power at 8000+ is inefficient. Also inefficient - not running enough compression with too much cam duration.

what would be the recommended CR for an NA 7AGE with smallport pistons and the 244 cat cams? I still wanna use 91 pump gas for the daily aspect of the build.

Including the costs for machining and sourcing the 7AFE itself to pull apart, I do believe I can pull a decent 7AGE build off that’s not only CA legal but also very fun! I appreciate your take on the build and I can incorporate it into what to do next. I finally have my space to actually work on and store my MR2 so I’m very excited to start parts collecting. You will see more on the thread in March or April.

[sirdeuce]

Do your math! Cimpression in a 7A block won't be the same as a 4A when using 4AGE pistons. Small port pistons in a 4A block have a 10.4-1 compression and in a 7AGE build it's closer to 11.7-1. Try to keep your compression closer to 10.5-1 for a smog engine to keep the NO to a passable level. As for cams? I've had my best luck with 225-230 duration at .050" cams. For smog day adjust the cams to smooth the idle. Don't go too crazy with the portwork, it can send you over the edge.

Doing a build that you want to pass cali's smog testing without issue and getting high numbers is quite a task, especially keeping the factory electronics.Be wary of the people that'll tell you to pump the compression to the moon and run 300 degree cams, those are the ones that don't have to pass California smog testing. OST is a good one to listen to, but I'm not sure if he knows how to pass smog. Stock electronics are the biggest hurdle. Best not to push it.

[ImpactEighty]

Try to keep your compression closer to 10.5-1 for a smog engine to keep the NO to a passable level.

That was the reasoning for using the Late GZE pistons. I was thinking that a 10:1 or a 10.5:1 would’ve been the recommended CR for 91 gas but I will double check ALL my math before any purchases or work done to the bottom end.

As for cams? I've had my best luck with 225-230 duration at .050" cams. For smog day adjust the cams to smooth the idle. Don't go too crazy with the portwork, it can send you over the edge.

.050”? Is that for valve lift? Also wouldn’t the stock big port can duration be 240?

Doing a build that you want to pass cali's smog testing without issue and getting high numbers is quite a task, especially keeping the factory electronics.Be wary of the people that'll tell you to pump the compression to the moon and run 300 degree cams, those are the ones that don't have to pass California smog testing. OST is a good one to listen to, but I'm not sure if he knows how to pass smog. Stock electronics are the biggest hurdle. Best not to push it.

Pushing things is the last thing I wanna do when handling with stock electronics. I know for a fact later down the line I want to get a new harness made and run a standalone. But that’s like WAY WAY down the line so at the moment I’m only focused on getting the motor built how I want it.

[sirdeuce]

Yeah, the bigport cam is 240 degrees total duration, probably close to 215 at .050" valve lift. That 225-230 at .050" valve lift would be somewhere from 250-265 degrees total duration. Shoot for lift over 8mm that won't necessitate shim-under buckets. The lower end of that duration range should idle close to stock and the upper range can do well enough if you play with the timing.
Once you get an idle lope the HCs and CO start getting difficult, the flapper door in the AFM jumps around and the ECU kida loses it. Typically gets easier to regulate after the engine speed evens out.
The 265 duration is about where you start getting your peak power close to fuel cut, anywhere from7200-7500rpm.

For a stand alone, the Megasquirt PNP is still available. Makes it a lot easier swapping your stock ECU back in every 2 years.

[ImpactEighty]

That 225-230 at .050" valve lift would be somewhere from 250-265 degrees total duration. Shoot for lift over 8mm that won't necessitate shim-under buckets. The lower end of that duration range should idle close to stock and the upper range can do well enough if you play with the timing.

So the .050" is around 1mm? If I'm understanding the conversion from inches to millimeters correctly that is. Looking more into the Cat Cams, I'm seeing two sets that look to be fairly within the recommended specs for the stock ECU and by both deuce's and OST's recommendations. So far I think these Cat Cams with either the 252/244 with 222/214 at .050" duration, and the 262/252 with 222/214 at .050" duration are what I will have to decide on when I get the rest of the headwork sorted out. I'm also going through Billzilla's website blog post about using cams around 256 duration.

I'm probably only going to go for a simple porting and maybe fitting a SC exhaust and have the exhaust side port matched like sirdeuce had suggested. keep it simple and inexpensive!

[oldeskewltoy]

stock early cams are 204 degrees at .050, later cams are 198.

Duration at a specific lift is a more accurate measure of a cam then "advertised duration"

As far as the Cat cams are concerned, I can also get matched sets (same duration for both).

Stock cams stop making power at 6600 rpm. The Cat 244 makes power to about 7000 - 7200.

Here is a compression calculator - http://www.csgnetwork.com/compcalc.html

stock bore is 81mm
4A stroke 77mm
7A stroke is 85.5mm
stock gasket bore is 82mm
stock gasket thickness is 1.25mm
stock chamber is 36cc
smallport piston dome is negative .25cc
largeport piston dome is negative 3.8cc
deck can vary, I like to use zero for the math, but by machining the top of the block, or getting a longer rod, or changing the piston's compression height- you can change the deck measurement.

[ImpactEighty]

ALRIGHT!! I’ve been doing a whole boat load of research these past few weeks. I’ve been doing the numbers, and rereading the thread to ensure I'm not missing a single bit of detail about building a 7AGE. I finally have a great list of what I'd like my 7AGE to be built out to be!

Starting with the bottom end:

- 7AFE block
- 7AFE crankshaft
- MRP 7AGE H-Beam Connecting Rods
- 4AGZE 8.9:1 Pistons (Late)
- King OE Bearings
- MRP Oil Pan (Spacer Included)
- Cometic .040" MLS Headgasket

The reason for the use of the 4AGZE pistons is because it fills the CR bump that comes with building a 7AGE better than most especially if I'm keeping it on pump gas. 10.5:1 is the main CR goal and it is something I wouldn’t want to exceed if I could help it.

Following up is the head. I’m going with a late Bigport 16v head with web cam 252/252 duration. I’m hoping you might be able to help me with that down the line oldeskewl? I’ll get in touch with you with more specifics.

Just for the parts, and machining to make the bottom end how I want it I’d be around the 2500 range give or take. I’ll be focusing on that first before moving on to any sort of headwork. Pictures of the car and parts collecting are on the way!

[oldeskewltoy]

Web no longer offers new cams, they do offer their hardweld service - this welds new material to the lobe so they can be reground without loosing "base circle". They are not cheap (currently listed for $1050 per pair) Just for discussion purposes..... Cat offers a 252/222 cam with 8.5mm lift. The 4 degrees shorter @ .050" lift may help low end power.

As far as a head - I happen to have a 2nd gen bigport - that is nearly finished - https://gallery.ostportworks.com/thumbn ... ?album=119