Wuich valve springs

[tta583]

Looking to do the valve springs on my motor as a spring project. Car has 27K origional miles and all stock internals. The usual bolt on upgrades - injectors, adj. WG, FP, 62mm TB etc.. I have no intention of changing the cam. The question is...what spring? I have had mixed response on the stock LT-1 springs or comp cams springs for a stick cam. Thoughts? I hear the comp cams are more precise in terms of open and closed pressure but I know they are a little heaver than the LT-1's so I don't want to wipe the cam after a short time.

The car is also an '89 TTA. Same spring as the g-body folks? I know the valve trains are different.

Thanks,

Brent

 

[salvageV6]

I would go with Comp Cams. 980's.

Don't really know what you mean by heavier?

Pressure with both springs and no cups is very close to the Buick spec., I measured mine.

Just my .02

 

[tta583]

SalvageV6

The Comp Cams springs I was looking at were the 941's. They have a seat load of 135#, an open load of 359# at a reat of 447. I don't know what the stock LT1 springs are. My understanding of the stock Buick spring is that it is about 90# at the seat, I don't have the other specs.

The 980's look closer to what I understand stock to be when comparing the only number I (think) I know about the stock set. The 980's look to be 91#ers.

Make any sense, what I said or even the comparison???

I will be the first to say I don't know, this is my first stab at this.

Brent

 

[UNGN]

LT-1 is NOT to be comfused with LT1.

LT-1 is a early 70's hydraulic cam 350, LT1 is a mid 90's roller cammed 350.

Putting LT1 springs in a buick will wipe the cam. LT-1 springs are just within stock 3.8L limits.

 

[tta583]

Thanks for that clarifcation. To be honest I knew there were "things" of a similar name from those time periods but to be honest, I never gave it much thought as to specify thinking the about the late model stuff as I was.

So go with late LT-1 springs? Stock LT-1? Comp cams equiv? Just new stock Buick springs and avaoid the entire mess?

Brent

 

[zam70]

I'd do (and I did do) the comp cams 980s, no cups. It's been a proven reliable upgrade/replacement.

 

[gofstbuick]

Actually, the valve spring used on the 370hp 350LT1 motor of the 70s is nothing more than a stock Chevrolet valve spring. That particular motor came with a solid lifter flat tappet camshaft. Those claiming to have Z/28 springs of the same vintage(60s and 70s), are using the same spring as above. If you want a heavier GM spring, the spring in my sig is for Chevrolet 1st Racing design camshaft. It is a very close match to the CC980 spring. Personally, I like the GM spring, but many on this board prefer the CC spring. IMHO you'll get good performance out of either spring. But if you're installing them with a new cam, just be sure to break the cam in properly. Oh yea, the color of the VS in my sig is a reddish brown.

 

[tta583]

Well, It sounds like the cc980's are the host ticket. Thanks, zam70, for mentioning the cups, I forgot to ask.

One more... Does any one have any thoughts on the TTA head? I know the upper valve train is different but are the springs the same?

Thanks again guys!!

Brent

 

[tta583]

Folks, any idea on the TTA heads?

I have also been doing some reading throught other threads. What should I be shooting for in terms of pressures at the seat?



Brent