Can LT1 Springs be used on stock L98 heads from an 87 camaro 5.7? These springs would be sufficient for an LT4 (non hot cam) correct? If not what aftermarket set will give me enough lift on the springs where they aren't coming apart like what I have now.

The stock springs I have on it decided to shed off some of the dampener spring and left a few chunks under the valve cover just loose. This is my daily so I have to do this the shortest length of time possible. I have another set of l98 heads with springs and I picked up a set or LT1 heads from a buddy. The springs were supposidly changed when the guy I purchased the car from had the cam installed, But how much of that is true is beyond me. Considering crap is coming apart.

We also found green seal pieces (valve seals?) and white roundish plastic pieces under the cover resting on the head also. Not a clue what those might be. The car is running super **** rice and when it gets up to op temp its running with no power and surges real bad.

I'm also having an idle issue probably from the heads. If I let off the gas to shift and push in on the clutch the tach is going from like 1000 up to 2000 and as soon as its in gear and my foot is released its back down again. Its going up to 2000 while i sit at lights with just my foot on the brake then it will drop back down when it sits still for a few seconds. Could this be a dirty IAC or sticking TB? I was stuck in traffic tonight for an hour the whole damn time it was at 2000 rpm after long driving. I'm burning gas and probably not doing the motor any good with it running up that high at idle.

 

That may depend upon what you mean by "LT1 springs." The valve springs used on stock LT1 engines built from 1993-1997 are one thing, while valve springs used on stock LT1 engines in 1970-71 are another thing. The later version LT1 springs are the same as the springs used for L98 heads - 85 pounds of seat pressure at 1.71" installed height. Since your cam has rated peak lifts of 0.476"/0.480" you will need springs which can tolerate those lifts. Moreover, you need to check your valve guide clearances very closely, since that is very near the point of interference with a stock head, and the evidence of damaged stem seals (We also found green seal pieces (valve seals?) and white roundish plastic pieces under the cover) further indicates you have reached the limits of lift on those heads. Continued operation in that mode may damage cam lobes, if it hasn't already.


Given that you have a spare set of L98 heads, I would advise that you concentrate on preparing those heads with machined guides and spring pockets (guides and pockets are typically machines in one setup anyway) to permit more than adequate clearance and allow a larger diameter spring. I would be very tempted to install screwed studs at the same time, and if it were mine, perform a bit of bowl hogging and port runner cleanup, and probably bronze valve guide bushings.

 

database error

 

Yes I was refering to 4th gen LT1 heads. Sorry I'm not too keen on 2nd gen info.
Keep in mind this is the LT4 cam not the LT4 Hot Cam. ITs a very mild cam. Where exactly do you find that "85 pounds of seat pressure at 1.71" installed height." at I have looked at summit and Sdpc2000 for info and what springs are required for the LT4 cam and have yet to find anything.
Mine
Chevy LT4, 203/210 Duration @ 0.050, Hydraulic Roller Camshaft
http://www.sdpc2000.com/catalog/540/products/1087/LT4-HOT-Cam-218-228-Duration-0050-Hydraulic-Roller-Camshaft.htm
The Iroc Z cam has more lift and duration then mine.
Chevy IROC-Z, 206/216 Duration @ 0.050, Hydraulic Roller Camshaft
Chevy IROC-Z, 206/216 Duration @ 0.050, Hydraulic Roller Camshaft :: 14093643 - SDPC

 

Actually, the 70-71 Camaros are second-gens...not first-gens

 

Thats what I meant the 60s are 1st gens. I was at work on here and I shouldn't have been I was just typing my **** off haha.

 

I bought what was called LT4 springs fgrom scoggindickies performance . SD1007 . @ 1.8"installed height it was 120 lbs. @ 1.2" it was 350 lbs. Stock 1.25 diameter. Also good for 570 lift.

 

All that means???????????

 

I just tossed out what SDPC gave me for my setup . you have two posts going on about what springs you can run without cutting the heads. I gave you an option. In your other thread too.

 

LT4 factory springs are ovate wire, and have 102# of closed valve seat pressure. Unfortunately, they measure closer to 1.34" than 1.250".

"P/N 12495494 (16 PCs of 12551483 ) - 1.3415"OD x 0.901"ID, 2.150 Free height, 101 Lb@1.780", 122Lb@ 1.710" 0.217"x 0.180" ovate wire."