Aftermarket valve spring discussion

Haven't seen a thread lately & talk seems to be scattered. So lets try to get some people to offer up some input on what that use/d for valve springs. I've seen stock, 910s, shimmed 910s, beehives, ext...
Post up your setups & what you run/ran & how it worked.

I'm just running 910's. I've heard of people having valve contact and stuff but I run my truck hard and haven't developed any problems yet.

What turbo setup you running right now Ross?

910's + .030 shim + .050 headgaskets + 3800 RPM's = slappy slappy...

Chvyrkr said:

910's + .030 shim + .050 headgaskets + 3800 RPM's = slappy slappy...

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Who's HG's?

IH, the infamous "blue stripped" gaskets.

Shimmed 910s here, seem to be fine so far but I haven't ran my truck hard yet cuz I'm still trying to dial my tunes in. My trans is shifting funny, an a few other things goin on, so I can't say I've had it wide open to many times or for any length of time

Chvyrkr said:

IH, the infamous "blue stripped" gaskets.

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You can't use those!!!!!!!!


LOL

So no fire rings?

910's shimmed to 1.75.....



WOP spring set up at 1.986....



ZERO issues!

Cat_rebel said:

What turbo setup you running right now Ross?

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I basically have a D66 with a late model compressor housing from River City Diesel. Injector's are 180's with a 30% nozzle. I still have generic tunes but with the 6 speed I'm not worried about trans tuning. 43lbs of boost and temps are great. From a stop to 100 I will finally hit 1300.

I'm wondering what the advantage of shimming the 910's is since some seem to be fine running 910's without shims.

You have to shim them, or they will be weaker than stock.

Shimmed 910's here on all engines that go out the door....

I am curious as well since we are putting a truck together with some good size hybrids and a 42R, what would you run?

907DAVE said:

You have to shim them, or they will be weaker than stock.

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Ok, so essentially you shim them to achieve desired valve seat pressure, no? If they are in fact weaker then factory springs, how are some running compounds with 910's and no shims yielding positive results?

Big Bore said:

You can't use those!!!!!!!!


LOL

So no fire rings?

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Funny you say that, 3 or 4 shops told me I'd be fine.

At the end of the day, I decided I should still have .020-.025 of piston to head clearance so I went with 'em.

And no fire rings. That engine didn't last long enough to ever present an issue by not having them.

TrailerHauler said:

Ok, so essentially you shim them to achieve desired valve seat pressure, no? If they are in fact weaker then factory springs, how are some running compounds with 910's and no shims yielding positive results?

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Because they ain't lookin at the pistons before they make those claims.

And possibly the valve seats are in remarkable enough condition that the shims aren't needed to get the spring back to an appropriate installed height.

Chvyrkr said:

Because they ain't lookin at the pistons before they make those claims.

And possibly the valve seats are in remarkable enough condition that the shims aren't needed to get the spring back to an appropriate installed height.

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That's what I was leaning towards, since no two trucks are the same I'm sure some would be fine without shims while others wouldn't.
The one truck that comes to mind though is Aggies (w/ truck source diesel). His old red reg. cab with a 38r over a gt47, I'm pretty sure he was running 910's without shims and had over 300k miles. But like you suggested the seats could be in good enough condition to not need shims, or there was some valve float he didn't know about.

Another dumb question, the springs need to be shimmed based on the height of the spring correct?

Yeah, you shim to achieve desired seat pressure, relative to installed height.

And I'd bet attention to properly gating boost/BP would go a long way.

Aggie's block and heads were bone stock at 300k correct? No way those valve seats were in the shape required to get away with non shimmed springs.

Stock springs, 38r and 238/80 hybrids equaled bent push rods, broken rocker towers, hydrolocked cylinder and blown head gasket all on cylinder #1.

Now running 4294r, 250/100's non shimmed 910's, pushing 52lbs of boost, about 65 back pressure with no problems so far.

New motor will have the Hypermax high rev valve spring setup.