rp0029

iTrader: (1)

I had Patrick g spec me up a cam for an lq4 which will have ls3 heads and stock springs for a daily driven 68 camaro. He recommended a 222/226 @ .050 with .566/.570 lift, 114 +4 lsa. Stock beehive springs on an ls3 are supposed to tolerate up to .570 lift.
I did as instructed and ordered the cam from Geoff at EPS. I had hoped to install it this weekend but when I opened the box I saw that either he or comp got it wrong. instead of 226 @.050 w .570 lift on the exhaust as recommended, the exhaust lobes are 230@.050 with. 572" of lift. This cam was supposed to work with stock ls3 valve springs, which are rated at .570.
Two questions - how will this cam behave? will it be suitable for a daily driver? And will 2/1000ths of an inch matter with the stock springs? I really don't want to wait another three weeks to install my engine.

nobreaks254

iTrader: (50)

IMO, stock springs are meant for stock cams. Get a set of springs and be done with it.

rp0029

iTrader: (1)

Aren't aftermarket springs noisy and hard on valvetrains?

rp0029

iTrader: (1)

What springs will last on a DD?

Jon@Texas-Speed

iTrader: (18)

Definitely put a spring in and a set of chromoly pushrods. I would go with a set of dual .650" springs. You could probably go with a PAC 1518 beehive spring as well. Remember you have a big intake valve so you will need a little better spring than the cam lift to control it at higher RPMs.

Jon

Geoff

iTrader: (3)

To the OP, would you give me a call? I'm not sure what happened and I can't tell who you are from a screen name. I will be glad to help you out what you need to do here.

Thanks.

LilJohnnyB

Dunno how drviable its gonna be, but she's gonna have bit of a rough idle for sure. I'm in a similar situation as you.. LQ4 with L92 heads and comp cams XR281HR which has .571 intake and .573 exhaust. I'm not sure which route I'm going with springs yet either, but here is an article from car craft where they swapped on L92 heads and LS6 springs with the above mentioned cam onto a LQ4 and got 550hp and the springs held up for the dyno just fine...how long they will last..I dunno..If they work now will they continue to be fine?

Car Craft article
http://www.carcraft.com/techarticles...ads/index.html

and here is what the Comp Cams XR281HR, 228/230 with 0.571/0.573 sounds like at idle, looks like he did the same swap, but with DBC
Personally, I really like the idle
http://www.youtube.com/watch?v=zsdog_LYrhM

snake charmer

iTrader: (118)

Usually the numbers are just out of safety but not too much .
Example ; Before Comp came out with the dual springs the original 918s were rated at .625 then when the duals came out they were bumped down to .600 .

Of course nobody wants to gamble a good engine with the wrench time .
There are some tricks to get a bit more but need to know the tricks pro .

Good luck

The_Bishop

iTrader: (10)

There is a lot more to valve springs than 'how much lift they'll handle.' The cam ramp rate, valvetrain weight, RPM limits all have a factor in the spring pressures. The lift is only one factor among several important considerations.

LilJohnnyB

Glad I decided to go with a set of comp cams bee-hives. What exactly is valvetrain weight?