SOME 4AG valve spring specs

[oldeskewltoy]

As per FSM specifications(AE86 and AE92) 4AG valve springs are to be checked @ 34.7mm(1.366")

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 -

Quote:some valve spring information...

http://honda-tech.com/all-motor-naturall...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 2 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"

[Bean]

I wonder what spec my Supertec springs would reach especial considering I got around .4" of valve lift (can't remember the exact number from top of my head right now).

[oldeskewltoy]

(05-01-2015 09:47 PM)Bean Bandit Wrote:  I wonder what spec my Supertec springs would reach especial considering I got around .4" of valve lift (can't remember the exact number from top of my head right now).

Got a vice? slip the spring in the vice and close the vice... bind is when the vice stops.... measure between the jaws of the vice.... wont tell you spring pressures, but will tell you bind, and the rest you can work backwards....

[Project D]

For Supertech:

-SPR-TC25S (single):

• 55lbs (244.5N) @ 35.40mm (with supertech retainer)
• 21.00mm Coil Bind
• 7.60lbs/mm (33.8N/mm)
  

SPR-TC25D (double):

• 73lbs (324.7N) @ 35.40mm
• 21.00/17.00mm Coil Bind (outer/inner)
• 12.60 lbs/mm (56N/mm)
  

So @ 10mm (.4"), if it's at valve lift (cam lift minus clearance)
single: 582.5N (131lbs)
double: 884.7N (199lbs)

oldeskewltoy Wrote:Got a vice?

Someone migh have seen my pictures on Club4AG facebook group
https://www.facebook.com/groups/Club4ag/...616589697/

[oldeskewltoy]

(05-02-2015 10:47 AM)Project D Wrote:  For Supertech:

-SPR-TC25S (single):

• 55lbs (244.5N) @ 35.40mm (with supertech retainer)
• 21.00mm Coil Bind
• 7.60lbs/mm (33.8N/mm)
  

So they are 14.4mm of lift @ bind using Supertech retainers? (35.4 minus 21)

Additionally... aftermarket retainers can offer some lift advantages... but we begin to mix up specs by mixing in none stock retainers. The Supertech springs under a stock retainer would be 34.7mm and bind is @ 21, so the Supertech springs under a stock retainer allows 13.7mm of lift before bind. What does Supertech recommend for maximum valve lift? (Do they abide by .050", or do they have less gap between bind and max lift like the Toda springs are alleged?

Other methods of gaining some lift is to machine the spring pocket, this will lower the spring and accommodate more lift. At some point spring bind falls away and the next clearance issue is the .060" that is recommended between the retainer, and the seal @ full lift. Again SOME room can be gained here by machining the top of the guide a few thousandths

[Project D]

Yes 14.4mm @ bind

And Supertech don't specify anything about maximum recommended valve lift.
I guess mainly because they know that you can't go even close to 14.4mm on the 4AGE head. (The wildest camshafts on the market for the 4AGE 16v are all under 12mm)

As a side note, the OEM springs are progressive while all the aftermarket (that I can think of at least) are linear.

BTW, I'm surprised you reach coil bind @ almost 26mm (1.017") with the OEM spring.
When I tested mine (on a vice) I was @ 25mm (0.985")