Max stock valve lift 16 valve

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oldeskewltoy
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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Tue Apr 28, 2015 11:12 am

I'm baccccck........... :)

Image

This is the tool i used, along with a caliper set to 1.366" (34.7mm) - The FSM specification for an installed valve spring - checked in 1986 AE86 FSM and 1989 AE92 FSM.


1.366" (34.7mm) This is our standard. All spring were brought to this point, and from this point on coil bind was found. On advicve from Loynings, .050" off coil bind is maximum "allowable" VALVE lift. I capitalized VALVE lift because it is different from cam lift* in this situation

*Coil bind doesn't change - with heating, valve stem length can "grow", but with the stems "growth", so will the spring, BUT when compressed, the coils will still bind at the same point - thus for purposes of valve springs - valve lifts, and not cam lifts are being referred too.

OEM stock (USED) - 35#s @ 34.7mm(1.366"), full bind comes in @ .349", subtract .050" and you are left with .299" before "effective coil bind". Pressure @ "effective coil bind - 96#s
    Since for this test I didn't have any new OEM springs I used 2 used springs. For point of fact... I recently did have some new OEM springs, and only 14 of the 16 springs actually met the minimum height in the FSM, the other 14 were within .03mm or less - spec is 41.09mm The two used ones I have measured out to 40.92, and 40.90. So they were pretty close.

HKS - 30#s @ 34.7mm(1.366"), full bind comes in @ .415", subtract .050" and you are left with .365" before "effective coil bind". Pressure @ "effective coil bind - 120#s

Toda - 42#s @ 34.7mm(1.366"), full bind comes in @ .419", subtract .050" and you are left with .369" before "effective coil bind". Pressure @ "effective coil bind - 128#s


I will be going back in a few days... I will confirm these numbers on a 2nd attempt later this week......
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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Tue Apr 28, 2015 1:19 pm

some valve spring information...

https://www.physicsforums.com/threads/v ... wn.553482/ - post 9 and 11 in particular

http://www.hotrod.com/how-to/engine/hrd ... vesprings/

http://honda-tech.com/all-motor-natural ... st44221375 - Honda VTEC thread of valve springs - many show specs of .2mm between bind and max lift

.2mm is a .008" or a LOT tighter then many accepted specs.....
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Tue Apr 28, 2015 7:24 pm

I don't understand how our numbers could be so different. Starting with an installed height of 34.7mm I get 10.5mm travel before my spring bottoms out.
I am not 100% sure this is a stock spring so I just ordered a new one from Toyota to help get to the bottom of this.

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Wed Apr 29, 2015 9:24 am

oldeskewltoy wrote:
Image

This is the tool i used, along with a caliper set to 1.366" (34.7mm) -

I will be going back in a few days... I will confirm these numbers on a 2nd attempt later this week......


When I go back I'll be going back with a new tool to help remove the slightest chance of a measuring flaw....

Image

The caliper I used once "asleep", when woken would be zero, this little tool will give me a reliable, repeatable setting for all the springs.

**IF** looking @ the Honda data is correct, the Toda spring would be VERY close to the 10.5 lift they once included in their info... MORE impressive is the HKS springs SEEM to be more than seat pressure.
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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Thu Apr 30, 2015 12:08 pm

oldeskewltoy wrote:
1.366" (34.7mm) This is our standard. All spring were brought to this point, and from this point on coil bind was found. On advice from Loynings, .050" off coil bind is maximum "allowable" VALVE lift. I capitalized VALVE lift because it is different from cam lift* in this situation.

From an unknown source -

some valve spring information...

http://honda-tech.com/all-motor-natural ... st44221375 - Honda VTEC thread of valve springs - many show specs of .2mm between bind and max lift

.2mm is a .008" or a LOT tighter then many accepted specs.....


*Coil bind doesn't change - with heating, valve stem length can "grow", but with the stems "growth", so will the spring, BUT when compressed, the coils will still bind at the same point - thus for purposes of valve springs - valve lifts, and not cam lifts are being referred too.

OEM stock (USED) - 35#s @ 34.7mm(1.366"), full bind comes in @ .349", subtract .050" and you are left with .299" before "effective coil bind". Pressure @ "effective coil bind - 96#s - Spring was bound @ 1.017"
    Since for this test I didn't have any new OEM springs I used 2 used springs. For point of fact... I recently did have some new OEM springs, and only 14 of the 16 springs actually met the minimum height in the FSM, the other 14 were within .03mm or less - spec is 41.09mm The two used ones I have measured out to 40.92, and 40.90. So they were pretty close.

HKS - 30#s @ 34.7mm(1.366"), full bind comes in @ .415", subtract .050" and you are left with .365" before "effective coil bind". Pressure @ "effective coil bind - 120#s - Spring was bound @ .951"

Toda - 42#s @ 34.7mm(1.366"), full bind comes in @ .419", subtract .050" and you are left with .369" before "effective coil bind". Pressure @ "effective coil bind - 128#s - Spring was bound @ .947"

BC 7MG valve spring - 58#s @ 34.7(1.366"), full bind comes in @.486", subtract .050" and you are left with .436" before "effective coil bind". Pressure @ "effective coil bind" 168#s - Spring was bound @ .880"



I went back today and checked all my previous findings, as well as checking a Brian Crower 7MG valve spring as BC told me they have sold a set or two of these to people running 4AGs... the BC spring fits into the 4AG steel spring seat and the 4AG retainer so since I have a set I checked them too. I also added the measurement of the spring @ coil bind to all findings
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Re: Max stock valve lift 16 valve

Postby turboae92 » Wed May 06, 2015 8:23 pm

Thanks oldskewltoy, great information. Aside from the seat pressure both hks and toda are very similar.I thinking of getting some 7mgte springs since will be upgrading from my hks springs.Hey would you want to sell your if don't have any use for them??

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Thu May 07, 2015 8:52 am

turboae92 wrote:Thanks oldskewltoy, great information. Aside from the seat pressure both hks and toda are very similar.I thinking of getting some 7mgte springs since will be upgrading from my hks springs.Hey would you want to sell your if don't have any use for them??



You can call Brian Crower and ask to buy 16 of their 7MG valve springs without retainers.....

The one thing I DON'T know is the quality/type of spring wire each of the different springs are made from.... What do I mean... quality/type of? If you do some research Toyota 7MG springs are about $6 each, Toyota 4AG springs are over $12 each. Their basic physical size is similar, yet the 4AG spring is more than twice the price..... this likely comes down to a much better quality spring wire used in the 4AG... likely because the 4AG must contend with a 1000 rpm more - stock.
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Thu May 07, 2015 11:10 am

So my brand new OEM spring measured at 9.1mm.
The strange thing is that it looks almost identical to my other spring. The other spring has a dab of faded paint on it just like the new one. Under the oil layer the finish and color looks identical. The wire thickness is identical. The only difference is that the new spring coil rotates around about 30 deg more. It doesn't seem like this should allow for another full 1.5mm lift. It does have me wondering if it is a stock spring and there is just this much variance or if it's just a very similar aftermarket spring. Unfortunately I don't have a good scale to measure the force. I really can't imagine this head had any aftermarket parts in it but I could be wrong. Maybe I'll have to measure the cams. They look stock.

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Re: Max stock valve lift 16 valve

Postby jdm86gtz » Thu May 07, 2015 2:43 pm

Going off of an AE101 GT-Z chassis number there are 2 springs available both listed with a quantity of 16 and both listed as 4A-GZE
Yellow 90501-33001 (This also comes up against my '87 Trueno chassis number)
Light green 90501-33002

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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Thu May 07, 2015 2:55 pm

jdm86gtz wrote:Going off of an AE101 GT-Z chassis number there are 2 springs available both listed with a quantity of 16 and both listed as 4A-GZE
Yellow 90501-33001 (This also comes up against my '87 Trueno chassis number)
Light green 90501-33002


That's interesting. I was wondering if maybe they changed the spring spec when they moved to the lower lift cams but it seems unlikely for such a small change.
Stranger still that they would show two springs on once chassis code. My new one is yellow. The old one is so oil stained I couldn't say for sure.
I actually just hit it with a scotchbrite and it seems more sea green. Of course who knows what heat and engine oil would do to the color after 25 years lol.

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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Thu May 07, 2015 3:06 pm

Lithiatoyota parts shows two different part numbers for the 85 Corolla GTS

9050133001

9050142003

85 MR2 shows the same

89 MR2 NA and GZE only shows 9050133001

Perhaps we have found the difference.
The head I pulled my valve from was a 3 rib. Perhaps the earlier spring has more lift and the earlier models just list the old part number and the one that replaced it.

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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Thu May 07, 2015 3:42 pm

So I had ordered the 001
I just ordered a 002 and a 003 to compare.
I may get a scale or load cell to measure pressure. Or maybe I'll just mail them to OST after I measure them.

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Thu May 07, 2015 4:31 pm

yoshimitsuspeed wrote:So I had ordered the 001
I just ordered a 002 and a 003 to compare.
I may get a scale or load cell to measure pressure. Or maybe I'll just mail them to OST after I measure them.


I'll be happy to check them and mail them back..... :D
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Thu May 07, 2015 4:49 pm

90501-42003 Has been discontinued and is no longer available.

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Thu May 07, 2015 6:45 pm

yoshimitsuspeed wrote:90501-42003 Has been discontinued and is no longer available.


I believe that is a valve spring for the SOHC "A" engines...
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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Tue May 26, 2015 12:16 pm

jdm86gtz wrote:Yellow 90501-33001 (This also comes up against my '87 Trueno chassis number)
Light green 90501-33002



Yoshi... I assume you sent me the 33001 - yellow, and the 33002 - green?? What is the third spring??

Image


did a quick search and the 33002 spring seems to not be from a US model... also seems the price is HALF... 33001 = MSRP $15+, 33002 = MSRP under $8.00


Odd... the spring 33002 seems to be available... yet it was not in any US model...
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Tue May 26, 2015 3:39 pm

1 9050133002
1 9050133001

The other spring was the used one out of my head. I believe a 9050133002 (Green) as well. This was a regular old three rib out of my friends AW11. Can't be sure it was the original but I believe fully stock and USDM.

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Re: Max stock valve lift 16 valve

Postby jdm86gtz » Tue May 26, 2015 4:23 pm

The 90501-33002 spring is only listed on a '91-'95 AE101 GT-Z 4A-GZE car. I checked for an AE92 GTZ and this spring wasn't available for it.

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Re: Max stock valve lift 16 valve

Postby Alex170984 » Wed May 27, 2015 4:52 am

I'm still running 8.5mm / 9.0mm cams on stock OEM springs

However have recently learnt I bent 8 intake valves when the belt snapped.

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Wed May 27, 2015 8:09 am

Alex170984 wrote:I'm still running 8.5mm / 9.0mm cams on stock OEM springs

However have recently learnt I bent 8 intake valves when the belt snapped.


How many miles?? if it was before 30,000, then it MIGHT be because you were so close to spring bind that it added extra stress to the belt.... not saying that is why... just might be a possible outcome
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Wed May 27, 2015 9:19 am

What are the 1.010 and .950 written n the bags?
What were the measurements from installed to hard bind?

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Wed May 27, 2015 10:23 am

yoshimitsuspeed wrote:What are the 1.010 and .950 written n the bags?
What were the measurements from installed to hard bind?


#s are: pressure @ 1.366", pressure @ full bind, and where full bind occurred. the rest you can work backwards


in addition... I can't know for sure... but I have a set of new Toda spring. No paint... just wondering if your used springs might be used Toda????
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Wed May 27, 2015 8:44 pm

oldeskewltoy wrote:
yoshimitsuspeed wrote:What are the 1.010 and .950 written n the bags?
What were the measurements from installed to hard bind?


#s are: pressure @ 1.366", pressure @ full bind, and where full bind occurred. the rest you can work backwards


in addition... I can't know for sure... but I have a set of new Toda spring. No paint... just wondering if your used springs might be used Toda????


The used spring is almost identical to the green spring.
I don't understand why the green spring number is lower. The green spring and used spring should have about 1mm to 1.5mm more travel to bind.

Pressure at full bind also doesn't make any sense because force/distance is going to get really messy a little before bind and go right out the window as soon as all the coils bind. It would be much better to do something like force at 8mm and or force at 1mm before bind.

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Thu May 28, 2015 7:18 am

yoshimitsuspeed wrote:
oldeskewltoy wrote:
yoshimitsuspeed wrote:What are the 1.010 and .950 written n the bags?
What were the measurements from installed to hard bind?


#s are: pressure @ 1.366", pressure @ full bind, and where full bind occurred. the rest you can work backwards


in addition... I can't know for sure... but I have a set of new Toda spring. No paint... just wondering if your used springs might be used Toda????


The used spring is almost identical to the green spring.
I don't understand why the green spring number is lower. The green spring and used spring should have about 1mm to 1.5mm more travel to bind.

Pressure at full bind also doesn't make any sense because force/distance is going to get really messy a little before bind and go right out the window as soon as all the coils bind. It would be much better to do something like force at 8mm and or force at 1mm before bind.



Title of this thread is max lift.... not pressures @.... but for the record I agree with you... BUT it is tough to go into a race shop and borrow their equipment.... without disturbing the ebb and flow of the shop.

Image

For the record, that is one of the pieces of equipment I need to have.... just don't have the capital yet to upgrade.
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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Thu May 28, 2015 5:43 pm

oldeskewltoy wrote:
Title of this thread is max lift.... not pressures @.... but for the record I agree with you... BUT it is tough to go into a race shop and borrow their equipment.... without disturbing the ebb and flow of the shop.

Image

For the record, that is one of the pieces of equipment I need to have.... just don't have the capital yet to upgrade.



So then what is the max lift? I am still confused by your numbers.

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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Fri May 29, 2015 7:18 am

oldeskewltoy wrote:
yoshimitsuspeed wrote:What are the 1.010 and .950 written n the bags?
What were the measurements from installed to hard bind?


#s are: pressure @ 1.366", pressure @ full bind, and where full bind occurred. the rest you can work backwards




yoshimitsuspeed wrote:

So then what is the max lift? I am still confused by your numbers.






So lets do the math together... :roll: 1.366" is the specification for the spring for when the valve is on the seat. We know the spring(for this example the 33002) hits full bind @ .950". So first we add .050" back into the equation as the standard for margin between bind and maximum lift capability - .950" + .050" = 1.000"

Next we subtract our result from the Factory spec, so 1.366" minus 1.000" leaves us with an "acceptable" lift value of .366" for the 33002. Now I know you are a PITA about using metric... so converting over.... 9.2964 millimeters is the maximum lift usable for the 33002
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Re: Max stock valve lift 16 valve

Postby oldeskewltoy » Fri May 29, 2015 7:25 am

There is one more thing to consider.... are these springs capable to run rpm level above stock??? I question this based on only one factor... pricing

the 33001 has an MSRP of $15+, while the 33002 has an MSRP of only about $7+.... this significant difference could be just a supplier difference... but then why is it only listed for 2 models????

I suspect, can't prove.... that the 33002 may not follow longer duration cams as well as say the HKS, or Toda springs
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Re: Max stock valve lift 16 valve

Postby jdm86gtz » Sat May 30, 2015 6:25 am

As you mention the rpm level, the AE101 gt-z ecu rev limiter is at 7200.

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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Sat May 30, 2015 9:49 am

oldeskewltoy wrote:


So lets do the math together... :roll: 1.366" is the specification for the spring for when the valve is on the seat. We know the spring(for this example the 33002) hits full bind @ .950". So first we add .050" back into the equation as the standard for margin between bind and maximum lift capability - .950" + .050" = 1.000"

Next we subtract our result from the Factory spec, so 1.366" minus 1.000" leaves us with an "acceptable" lift value of .366" for the 33002. Now I know you are a PITA about using metric... so converting over.... 9.2964 millimeters is the maximum lift usable for the 33002


Sorry for not following the first time. It never would have occurred to me to measure things in that manner. I would have expected you were measuring distance to bind not off actual height while compressed.

And yeah using metric on metric motors seems to make sense. I don't know why so many Americans are such a PITA about using non native and far more inferior units of measurement.

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Re: Max stock valve lift 16 valve

Postby yoshimitsuspeed » Sat May 30, 2015 9:57 am

oldeskewltoy wrote:
I suspect, can't prove.... that the 33002 may not follow longer duration cams as well as say the HKS, or Toda springs


Also duration is not the issue. In fact a spring will follow a 304 x 8.2mm cam to a higher RPM than it will follow a 264 x 8.2 cam. It is the lift and more importantly the lift to duration ratio. A spring will have more trouble with a 264 x 10.4 turbo cam because it is accelerating open at a higher speed, the mass has more inertia pulling it away from the lobe and then the lobe is dropping away from the spring faster meaning you need more spring to keep it in contact with the lobe.
Just rough guessing if you increased the ratio the same I would guess the max RPM would stay about the same. So if you can spin a 264 x 8.2 spring to 9000 without floating then multiply each by 1.1 and I would expect you could run a 290 x 9 to the same RPM without floating.
The longer the duration the more time the spring has to keep the follower in contact with the lobe and as with most things force / time is what matters.

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