OST-029: California here I come.....

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oldeskewltoy
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OST-029: California here I come.....

Postby oldeskewltoy » Tue Jan 06, 2015 1:26 pm

Image

As I always do... my client is anonymous, unless he wants to share. This head is sold to a client in California. This is his daily driver, that gets a track beating/work out every few months or so. Retaining emissions compliance is paramount, but we can get a bit more without offending the sniffer.


This is a largeport head, it is the stock thickness, having never been re-surfaced.

Image


A key for me in figuring out overall "wear" is often judged on the condition of the old valve seals. The old seals that came from this head were still "pliable" (read as didn't crumble under finger pressure) - A few intake valves did show signs of build-up, the exhaust valves were all dry.

Image


#4 exhaust port

Image


Its pretty crowded in there, but a bit of seat to bowl blending, and a re-taper of the port will allow the exhaust gasses an easier path


Now that it is stripped, its off the the machine shop to get cleaned, and de-carboned. Maybe they can get rid of that horrid paint for me too




More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Billy_Andrea
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Re: OST-029: California here I come.....

Postby Billy_Andrea » Wed Jan 07, 2015 4:58 pm

Looking forward to seeing this progress.... Love how you get very good performance from a street / emissions legal engine.

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Mon Jan 12, 2015 8:12 am

Billy_Andrea wrote:Looking forward to seeing this progress.... Love how you get very good performance from a street / emissions legal engine.


Thanks Billy........ unfortunately it will not be with this head.........


The one head I sent out for cleaning, and pressure testing has pretty significant flaws....



Image

Chamber #3 is not quite the same depth as chamber 4... you can see this by comparing "a" and "b' in both heads. and you can see heavy machining. Chambers 2 and 3 are pretty bad, 1 is just a little bad, and 4 is "ok". All those chambers have significant flaws, and it just isn't economically feasible to fix the flaws.... so I'm after another head.....




more to come...... :D
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby sekang0 » Thu Jan 15, 2015 2:16 am

Excited to see another thread from you! Too bad the head is no good.
'85 GT-S project since 2010
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Re: OST-029: California here I come.....

Postby oldeskewltoy » Mon Jan 19, 2015 12:00 pm

sekang0 wrote:Excited to see another thread from you! Too bad the head is no good.



Take 2........


Image


The old head on top, the replacement below.... chambers are far better shaped!

Image


More to come........ :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Tue Jan 20, 2015 4:50 pm

Easiest way to begin is showing you another 2 panel of chambers 3 and 4.... the top one you've seen before...

Image

... the bottom one is new - Cylinder 4(on left) is where we begin.... all four bowls and seats have been blended, as well as the chamber deshrouded and intake guides minimized, the seats in #4 just need their valve job.


How observant are you???? What else have I done that I didn't tell you?? :wtf:


The intake bowls, and seats - 4 is shaped(on left), 3 is untouched.. Bowls are now round, blended out to meet the seats, the shape is carried out to the port. The short radius transitions smoothly from port floor to the valve seats, and the guides have been minimized.

Image


Chamber... Intake.... and now exhaust


A comparison between 4 (on left) and 3

Image


and a 2 panel showing progression of #4 from half shaped, to fully shaped

Image


More to come.... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Jan 21, 2015 9:32 am

from another forum wrote:The magic has begun!


Image

(above pic was posted to one of my earlier build threads... had to use it again....:D )




.... and now back to reality.... ;)

from another forum wrote:How often do you come across variations in the chamber depths? I can't say I noticed it on my spare head, but I didn't look closely either.


The head this thread began with, that since has been replaced is the worst head I've seen. I've had to discard other heads because of flaws before*, but this is the worst head, at least in regards to correct chamber shape, that I've seen.

* - http://hachiroku.net/forums/showpost.php?p=350771&postcount=7


A short annotated photo showing the areas of work, and the similar area before work - no "hogging" here

Image

the translucent redline shows us the port floor

1) The short radius - a gentle curve to the valves edge to promote cylinder filling
2 & 3 ) shaping the bowl to the seat, further promote cylinder filling
4) "Opening" the passage between the splitter and the guide, allowing the airflow easier passage past the guide - once again to aid in cylinder filling.

Nothing drastic, just taking a mass produced part and making it better ;)




More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby candamo » Wed Jan 21, 2015 3:50 pm

At first didnt notice the heavy machining on the chambers. Gotta train the eye better.
I was like...
Image

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Jan 21, 2015 5:43 pm

oldeskewltoy wrote:
from another forum wrote:the intake valve on the right got slightly more space to breath...


The chambers edge around the right intake valve has changed a tiny bit, so technically you are correct,


Why did it change??

Chamber edge... this time cylinder 3. On top is the chamber edge before any work, you can see the old gasket, so that edge "sat" in the combustion chamber, the photo below shows after removing the half that is toward the exhaust valve (right)

Image

Note how significant a flaw the edge of the chamber actually is.... when measured... it is .48mm "tall", and it is .73mm "deep", or sticking into the chamber is a sharp edge. So how significant is it...??? see the little green arrow, that arrow shows where I placed the dental pick....

Image


Edges are NOT GOOD, they promote detonation, and this one stick "in" like a sore thumb :(


So... that is why the edge of chamber four around the right hand valve now has a bit more room to breath.... and it is likely that all the chambers will show this change as well


More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Thu Jan 22, 2015 2:38 pm

Image


Since the last post was a brief discussion about that edge... I thought a short gif of the progression of the chamber walls....


although "polished" in the last scene, it wont be finished till after I have chamber volumes, and adjust accordingly



And now for exhaust port #3

Image




More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Mon Jan 26, 2015 4:55 pm

Image


exhaust port #2 mid work



Chambers 4, 3, and now 2 deshrouded

Image



Intake short radii on 4, 3, and now 2....

Image


More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Thu Jan 29, 2015 5:22 pm

from another forum wrote:Looks real good especially the short turns and the chambers.



exhaust #1

Image


all the chambers
Image


More to come........ :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Tue Feb 10, 2015 1:58 pm

oldeskewltoy wrote:
Image


More to come........ :D


After the cut, with the valves fitted... waiting for checking chamber volumes....

Image

This head was cut .018" (.457mm) My caliper can't figure out if it is .45, or .46

Image



"Volumes" to come........ :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby yellowsnow4free » Wed Feb 11, 2015 12:35 pm

oldeskewltoy wrote:This head is sold to a client in California. This is his daily driver, that gets a track beating/work out every few months or so. Retaining emissions compliance is paramount, but we can get a bit more without offending the sniffer.

Hey OST,

First off, great work :) I'm trying to learn about head work and your threads are very useful; great documentation!

Being in California myself, I'm curious what limitations emissions compliance places on the head work you're doing.

I'm thinking of eventually (probably years from now) doing some work on a 4AC head, and being in CA I'm curious what head work should / shouldn't be done on a car that has to pass smog.

Thanks! :D

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Feb 11, 2015 1:15 pm

yellowsnow4free wrote:
oldeskewltoy wrote:This head is sold to a client in California. This is his daily driver, that gets a track beating/work out every few months or so. Retaining emissions compliance is paramount, but we can get a bit more without offending the sniffer.

Hey OST,

First off, great work :) I'm trying to learn about head work and your threads are very useful; great documentation!

Being in California myself, I'm curious what limitations emissions compliance places on the head work you're doing.

I'm thinking of eventually (probably years from now) doing some work on a 4AC head, and being in CA I'm curious what head work should / shouldn't be done on a car that has to pass smog.

Thanks! :D


my goal for an emissions compliance head is to optimize everything, yet change nothing. Yeah sounds confusing... Look carefully, all I've done to this head so far has been to clean up relatively obvious flaws in the casting, I've not changed things in this head like I did with OST-028, that head got a reworked roof, and the intake bowls around the guides were more extremely worked - that head is using the pon cams, and he is running carburetors so little hope of emissions compliance (none in Cally)
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby yellowsnow4free » Wed Feb 11, 2015 2:44 pm

oldeskewltoy wrote:My goal for an emissions compliance head is to optimize everything, yet change nothing. Yeah sounds confusing... Look carefully, all I've done to this head so far has been to clean up relatively obvious flaws in the casting, I've not changed things in this head like I did with OST-028, that head got a reworked roof, and the intake bowls around the guides were more extremely worked - that head is using the pon cams, and he is running carburetors so little hope of emissions compliance (none in Cally)

Cool, thanks for the info! :D I think I get what you mean :)

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Feb 11, 2015 4:37 pm

from another forum wrote:Since this head is coming here to Cali. Is the customer going to do any kind of camshaft or just use the stockers? I'd be curious I know that my web cams in my N/A engine wouldn't pass smog.


Really? which Webs? My AE86 used the Web 294 grind and they passed, albeit with a new OEM type cat, but they passed. And I'm pretty sure OST-019 passed using a mild cam, but it needed a bit of ignition timing tweaks to pass.

Most likely my client will be running a set of the "big", or early stock cams if he can get himself a good pair. There is a Cat cam that MIGHT work, its their shortest, lowest lift cam, it measures 214 @ .040" lift, with a gross lift of 8 mm. The Web 294 cam is 214 also, but @ .050" lift.


oldeskewltoy wrote:"Volumes" to come........ :D





Checking chamber volumes on the cut head.... it is down to 35.1cc (tolerance = + or - .1cc)

Image


So we can move on... besides waiting a week for the machine work, that same time was used to get new springs....

Image

16 new OEM springs...


Now its just left too assembly.....



More to come..... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Thu Feb 12, 2015 3:26 pm

Amazing what isn't seen...

Image

A great deal... but its all there. From the top view you miss out on #1, and much of #3 but #2 and 4 are quite evident.

Since this is a California head I've left the swirl generators, but managed to adjust their shapes to something a bit more uniform, one needs a bit more work - does anyone know wtf I'm talking about :lol:


Did it get the super 5 angle valve job?



3 angle with back cut intakes

Image


More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Sun Feb 15, 2015 11:33 am

from another forum - non USA wrote:California ? would those mod affect the ca emission drama on there ?


They shouldn't....... Nothing I've done is actually drastic. For the most part I'm just improving the original casting by port matching the seats-bowls-ports to more closely match the original design. The surface machining of .018" is not beyond the normal range. A multi angle valve job is not beyond typical. The slightly raised compression will not hurt either.

The client has selected to run a pair of MILD upgrade cams. He purchased 2 exhaust cams from Cat Cams 7105136 on my recommendation. They have the same timing as the OEM cams, they have a bit more lift, and a bit more duration... without it going to an extreme (emissions unfriendly)


from another forum wrote:
What are swirl generators? I can see everything else you pointed out thanks.


First apologies... the more common, and in this case correct term is actually "tumble generators"


Image


This kind of tumble generator promotes lower air speed performance by causing the incoming air to rotate as it approaches the valve. The theory is it helps to fill the valve area better. It also may act as a passive emissions device... to further aid in air-fuel mixing so more complete combustion can occur.



More to come.... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Enjoy Life... its the only one you get!

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Feb 18, 2015 2:56 pm

Installing valve #8... apologies to AC/DC... my timing was off by about a second.... :lol:

http://youtu.be/fu2GHerEnME
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Thu Feb 19, 2015 2:12 pm

The valvetrain is now assembled....

Image




Cam caps buffed....

Image


Just waiting on those new cams.....



More to come...... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Sat Feb 28, 2015 3:59 pm

from another forum wrote:The cams will arrive to me on Tuesday. I will ship them out to you by Thursday.


received....

More to come..... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Tue Mar 03, 2015 9:32 am

As I alluded too, the cams have arrived. They are a pair of Catcams 7105136 exhaust cams. As the box labels, and the cams indicate.

Image

Since I'm setting the valve clearances, and the cams are more or less identical, I've labelled them "I", "E" so there can't be any mixing of one to the other. This will also help my client get them back in the right places once the head is bolted on.






These are a MILD bump in duration and lift over Bluetop cams.

Image


Just a reminder... early TVIS cams are 240 total duration, 204 duration@ 1mm lift, with 7.5mm cam lift.



Ok, why go with such a "mild cam" a few reasons: 1) California emissions, that on its own can make or break this build. 2) My client is keeping the stock 9.4 to 1 pistons - he will be adding a thinner head gasket, and the chambers are smaller, but this engine won't be breaking past 10 to 1, so keeping as much trapped compression (DCR) is important. The ramp on this cam is pretty aggressive ("foot" is only 13 degrees) so even though the cam is "mild", it isn't as mild as the numbers appear...

Image

The intake timing @ 1mm lift for this exhaust cam used on the intake side would be 4ATDC to 36ABDC. Now add in the head cut to the cam timing (albeit not a huge amount) will move cam timing closer to 2ATDC and 34ABDC... all with 8mm lift and all the "extra" duration from 1/2 lift on.

Only time will tell, but this should bring a nice LEGAL smile to my client :mrgreen:


More to come...... :mrgreen:

EDIT - not thinner headgasket, so only compression bump is from 1cc smaller chamber (about 9.6 to 1)
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Mar 04, 2015 5:30 pm

So last "quiz" on this head....

What's up?

Image


more to come..... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Fri Mar 06, 2015 9:42 am

oldeskewltoy wrote:So last "quiz" on this head....

What's up?

Image


more to come..... :D



:roll: really? no one even has a guess??? Even a quick view @ the pic title gives MOST of it away.... "disassembled_exhaust_valves_for_tipping.jpg"

How much easier can I make it??? :lol:


alright.... what is seen above.... the intake cam is in, the exhaust cam is not only not in, but all the exhaust valves are out in box-stock type cardboard, each marked with two series of numbers (1-8), and a second series that appears to be measurements (apologies for not marking the type of units used).

So the story.... The new cams were unpacked, and I began on the exhaust side. I used all 2.9mm shim to begin, and once the cam was tightened into place, and I checked... I managed to get 3 readings... all .0015" (spec on exhaust is .25mm, or .0100"), the other 5 were just too tight to even get a measurement. So, I removed the 5 shims, and fitted 5 of the thinnest shims I had, remeasured and found to get proper clearances I'd need to order 7 shims ranging from 2.5mm to 2.70mm.

To make a LOOONG story much shorter... the second series of numbers that appear to be measurements are measurements of how much each of the exhaust valves need to be tipped. Tipping the valves will get their clearances back to a range were special ordered shims are not required(2.8-3.1). It will also allow for a 2nd valve job to be done on this head and still be able to shim it, something that would not be possible if I didn't tip the valves today.

Now the good news... the intake side was set just fine, no weird things there. 5 valves are set @ .008" and the other 3 are @ .009"




more to come.... :mrgreen:
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Mon Mar 09, 2015 3:26 pm

This head is now done! intake and exhaust valve clearances have been set.

Image


Now to get it boxed up and on its way to its new owner ;)
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: OST-029: California here I come.....

Postby Gino1X1 » Tue Mar 17, 2015 10:14 am

Great job as usual, meng. The shimming of cams/valves is something I really haven't gotten into as it iz a tedious job for me. Don't have the time and such....

L'il confushion I'm having is with the valve springs, as it's stated as OEM. The ramps of the lobes on the new cams are more or less steep as far as I can see... won't that put more strain on the OEM components at rpm limit.

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Re: OST-029: California here I come.....

Postby oldeskewltoy » Wed Mar 18, 2015 7:57 am

Gino1X1 wrote:
L'il confushion I'm having is with the valve springs, as it's stated as OEM. The ramps of the lobes on the new cams are more or less steep as far as I can see... won't that put more strain on the OEM components at rpm limit.


yes... OEM valve springs have been used in all kinds of "performance" builds utilizing mild to medium cams. Additionally, the Catcams timing card does NOT indicate the need for a more aggressive spring - http://www.catcams.com/products/camshaf ... TUP_id=827

Typically... for me... once the lift goes over 8.1mm(valve lift), or duration goes above 264, that is when I consider a performance spring.
OST Cyl head porting, - viewtopic.php?f=22&t=300

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