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Discussion Starter #1
SO after further verifying the integrity of my wiring with load and resistance tests, I was kinda curious as to why the valve spring I pulled off this 287 G head, was so much shorter than the spring I pulled off a swirl head, is there any validity to if one is from say, a carb/TBI spring? And maybe this is my issue as far as 5k breakup/brick wall (which may be a severe case of valve float)? As far as I can tell this is just a reman 287 head nothing super special.

HX35
287 G head
Ported one piee
ported exhaust mani
95 lb injectors
-6AN throughout
AEM inline 400 fuel pump 100 micro pre and 10 micro post filters

1989 SMEC electronics from a van including engine harness, socketed with a OSTRICH
 

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Discussion Starter #2
Compression and leakdown have also been done, 125 even on all four less than 10% on all four, done Hot AND Cold. and that was only with 80 psi in the leakdown tester aswell.
 

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That doesnt look right.
I havent seen white marks on springs that i have seen before.
and yess if they have less pressure they will float.
might be your brick wall.

Suggest you spend 80-150$ converting to beehives and trying it again.
 

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N/A springs look just like Turbo springs.. same length etc

never seen one with those white hash marks ..

+1 of the conicals, my 2.2 spun hard and clean right to redline :)

if yur on a LOW $ budget get used 3.3 springs, used 3100 retainers, and used PT lifters ;
all cheap or even free at yur local junkyard just takes some time to scavenge
 

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pretty much on the budget stuff.
either buy new from rock auto. or hit the local yard.
find the nearest PT cruiser remove valve cover. if questionable or varnished at ALL
move on to the next one. as there will be at least a dozen in the yard.
you need 8 lifters.

go to nearest 80's-90's GM FWD turd. look for an engine that says 3100 on the plenum.
remove valve cover. remove retainers.

order 3.3 springs from rock auto for like 3$ a piece. you need 8.

Order shims from a vendor here.

It will be a whole new car when it goes back together.
 

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With a 3.3 spring you need a .050 shim under it. Seat pressure is about 60 without shims. This is for a stock roller cam too. 88 TBI cam as the best choice. BTW the valve train has high rocker ratio that breaks down stock springs. Above 5k and doing 6k plus the spring pressure stock degrades fast. I've has a range between 60 and 115 for seat pressure after 5k miles. Next the lift traps windage and makes the lifters squish instead of opening the valve at 5k RPM. Thinker oil like 20 50 makes this worse. Beehive springs are designed for high rocker ratio and the lifters are just a newer shorter updated stock design. They just need a shim. Basically I came up with this mod for the problem you are having. I'd start out shifting at 6500. Then not long later at 5300...... NA people should buy the comp springs, a few mods and 8k RPM lol. BTW I think detobias has run the same springs and lifters almost 15 years straight now. So they last
 

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Discussion Starter #7
The thing is this car has NEVER gone over the 5k rpm mark, since its been together. The picture of the valve springs was just a thought of mine, the ones on the left I swapped out for the ones on the right, the shorter ones didn't really feel "weak" but the height of them is kinda what got me stumped and wondering if this coud be an issue. I also am running PT Lifters and shims, so not sure if that has a factor either
 

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Stiffer springs designed for the same installed height are shorter just sitting. It's tough to eye them you need a spring tester. FYI the 81 655 to a 03 Chinese 021 head, they all use the same springs. The valves changed in length. The MP springs with dampener are pretty cheap. Not the S60 springs. That may be a good easy choice. Not going to 5k can be a few things like cam timing as well. The only used springs you can use are 3.3 springs or maybe magnum. No 2.2 spring should get used and reinstalled in a head.
 

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that short of a spring wont produce the same pressure as the larger spring when closed. it will also SEVERLY limit RPM due to not controlling the valve at higher RPM's.
 

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that short of a spring wont produce the same pressure as the larger spring when closed. it will also SEVERLY limit RPM due to not controlling the valve at higher RPM's.
ONLY when the coils are the same. Stiffer / stronger springs do not require as much compression. Anyone that has installed lowering performance springs on a car knows this. Stock springs are nearly twice as long as soft stock springs. That is why you can't just simply eye ball springs. Test both at 1.7" installed height and test seat pressure
 
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