Rezi1987TA

Anyone? :-S
I need to buy a set of springs as soon as possible but I can't open the engine for another 2 weeks or so...
The car is a 87 TPI 305 Trans Am stock that will receive a cam upgrade soon.
The cam will be:
http://www.summitracing.com/parts/CRN-104224/

Thanks.

burnout88

If you are going to use the crane 2032 cam use this chart to match up your springs, retainers and pushrods.

http://www.cranecams.com/88-89.pdf

Kevin91Z

iTrader: (1)

The Manley Performance 22410-16 springs will fit the stock heads and allow you to run more lift.

http://www.jegs.com/i/Manley/660/22410-16/10002/-1

You can use either the 23651-16 steel retainers or the 23652-16 +0.050" steel retainers if you're going to use 1.6 rockers as well.

85 Frankenstein

In my 88 factory service manual it gives 1-23/32 for the intake and 1-19/32 for exhaust "installed height" if that helps at all. Also my 88 305 TPI has the 081 head casting numbers

Orr89RocZ

iTrader: (20)

If those are correct then thats 1.718" intake and 1.594" exhaust...seems very small on the exhaust. Most springs want to be around 1.7-1.8 on sbc heads.

88fastgta

iTrader: (9)

i ran that same exact cam in my old l98... you really dont need springs with the 2032 but since your that far i would change them out. thats what i did... here is a idle video of that cam in my old bolt on l98 engine

http://www.youtube.com/watch?v=Yja12X-pCsI

Rezi1987TA

Thanks a lot for the replies!
I guess I'll get the Manely springs. Anything else that I need or would be nice to get?

Rezi1987TA

Also...should I use the .060" Valve Spring Insert that I'll receive soon? :-S

85 Frankenstein

Does anybody think the installed height of 1.594 on the exhaust is because of the rotators? I am in the middle of putting together my engine 88 305 TPI with the stock cam .430 exhaust lift with the stock rockers .458 with the 1.6 rockers. If my service manual is correct I will run into coil bind issues. 1.594(installed height)-.060(minimum clearance)-1.115(coil bind comp cams 981 spring) gives me an allowable lift of 0.419 which is less than what I need (.458) I have never done this stuff before can anybody tell me if my train of thought is correct. If thought process is correct would removing the exhaust rotators be the right fix? Thanks

Orr89RocZ

iTrader: (20)

I'm not sure why the exhaust side is soo short. The rotators could be the problem, but I ran 1.6 rockers on my L98 with stock springs and that would be .459" lift. Never had a problem. I'd take the rotators out and see what your heights are then.

reride

iTrader: (1)

Make sure what lift these cams take the measurement at. It could be taken at .020 or .050 lift, this could effect the measurement. This might apply more to lift & duration then valve spring height, sorry for senior moment.

85 Frankenstein

Thanks for help guys I think I am going to remove the rotators just to be on the safe side. Hopefully this will put me in the 1.7 range. I will have to measure the thickness once I get one off.

85 Frankenstein

Well, I pulled an exhaust spring and cut a piece of toothpick until it fit the spring seat. I accidently cut off a little too much so it had a little slop an it measured 1.69. This completely contradicts the shop manual.

Damon

Some earlier heads that used rotator/retainers on the exhaust had shorter springs on that side. But all the later model heads I've worked on they cut the exhaust spring pocket deeper to compensate for the extra thickness of the rotator/retainer. They're all about 1.70" from the factory with reality being a hundredth or two taller than that.

If you're ditching the exhaust-side rotator/retainers for non-rotator/retainers (standard retainers) then install a .060" shim in the exhaust spring pocket to bring you back up close to the stock 1.70" spec.

Common drop-in upgrades to stock springs (requiring no machining): Comp 981 springs and eBay "Z28" springs.

85 Frankenstein

Thanks for the help, I decided to keep the rotators after discovering that I am at the correct installed height with them. The spring seats do appear to be machined deeper on the exhaust side. If it aint broke don't fix it kind of thing. I figure they can't hurt anything and I stick to the lower rpm range. Thanks again