comp springs and stock seat/seal

[3400-95-Modified]

My 986's have been fine, yes I'm loosing a bit of spring rate but I havent had any valve float issues...

[Superdave]

comp retainer and stock locks look good, i'll check the IH when i get some time..

[3400-95-Modified]

When your measuring IH your going from base of spring to top of spring correct? excluding the seat and the retainer?

I have the stock IH of a 3500 head with LS6 springs, and well obviously the IH will not change from spring to spring if you use the same seat and retainer/locks

[Superdave]

I use a dummy spring to hold pressure on the valve/retainer and use the caliper to go between the seat and retainer.

[gectek]

When your measuring IH your going from base of spring to top of spring correct? excluding the seat and the retainer?

I have the stock IH of a 3500 head with LS6 springs, and well obviously the IH will not change from spring to spring if you use the same seat and retainer/locks

well this ONLY applies in a walgreens world. the seats/heads/srping pockets are never exactly the same height from one valve to another....unless you use a VERY high quality head, meaning not stock GM lol.

[ForcedFirebird]

well this ONLY applies in a walgreens world. the seats/heads/srping pockets are never exactly the same height from one valve to another....unless you use a VERY high quality head, meaning not stock GM lol.

Correct. GM has a tolerance to stay between when machining the seat pockets, some can be on the high side, some on the low, making the difference between them significant.


Ben, with having to press the seats in the spring like that, the only concern I could see is that when a spring is in motion, it and the valve spins. I wonder what effect that will have on the seat/seal if it spins with the spring? I have seen high speed videos of springs before, I'll see if I can dig them up...

EDIT: http://www.network54.com/Forum/74182...+the+Stock+Cam

[3400-95-Modified]

well this ONLY applies in a walgreens world. the seats/heads/srping pockets are never exactly the same height from one valve to another....unless you use a VERY high quality head, meaning not stock GM lol.

Well yeah ok, thats understandable, But I was simply quesioning my distance that I was measuring... I wanted to make sure I was measuring the right part.

I never expected to be able to measure one valve and have them all be the same, but I figured that if you use the same parts to install different springs then your install heights wouldn't/shouldn't change from spring to spring.

[gectek]

they will. just because of the seat being higher in the head. or the spring pocket being lower. that would change the total distance of the valve or the spring installed then.

[SappySE107]

Or bad keepers...pwnage! If you used the same seat, retainer, and keepers and measured each install height, it would be pretty close.

[3400-95-Modified]

they will. just because of the seat being higher in the head. or the spring pocket being lower. that would change the total distance of the valve or the spring installed then.

Yes, but your overlooking it here...

If I measure ONE valve with a stock spring seat keeper and retainer, the IH will still be the same if I were to replace that stock spring with a 986, only on that one valve.

I'm not saying every spring IH is the same with the stock parts because yes the heads varry from seat to seat.

[gectek]

oops...yah im just thinking about in general over the entire head. but ben has seen some nasty stuff from the comp stuff, so its kinda hard to say yes. ideally yes tho