hi my new cam have a 1.440 basecircle,and what i understand the stock ls1 cam have 1.551 basecircle?

1.551-1.440=0.111/2=0.0555 so should i get 7.450 push rods?

2 question.

my cam spec are 224/231 0.578" / 0.588" int/exh lift 114 LSA.
i bought the cam for n/a setup,but now iam going FI.
how would the cam work with my procharger?

/jimmy sweden

 

Typically aftermarket cams have a smaller base circle. Most of the time they still work well with a stock length pushrod. Sometimes people will select a 7.425 bc with a 7.400, their lifters are noisy.

 

7.425 or 7.450 should work with that cam, you're math is right. The 7 degree split in your cam should be good for a procharger under 8psi. 8psi+ might need a wider split to be ldeal.

 

Keep in mind the stock pushrods' gauge length was about 7.38x", not 7.400"! The issue with using that math is that you don't know how much preload those pushrods made on the stock combo....what if it was higher or lower than you'd like???

 

My stock pushrods calipered at 7.40x, just as an FYI.

 

That's not gauge length though

http://www.trendperform.com/measuring.html

There's a little reading for ya. Aftermarket pushrods that are 7.400" when you order, end to end measure 7.415-7.420", FYI.

 

what happend when the pr is to long or short?

 

Too long and it can cause the valves to hang open, thus not building cranking compression or being able to start. Too short can cause lash (opposite of preload) on the lifter and will beat the H3!! out of parts, make a ton of noise, and ultimately cost you grips of money!

The tool to measure for pushrod length is only $20...it doesn't make sense not to do it right!

 

While what you quoted may in fact be true, the average joe may not know this. If they go to measure pushrods using a caliper it could lead to order the incorrect length. So its important to point out that a stock pushrod calipers out at 7.40x

 

Knowledge is power...if you order based on your stockers being 7.40" tip to tip, you're going to order the wrong ones. Do you call up and order pushrods that are 7.400" tip to tip to get the same as you had from the factory?? No, you order gauge length, which would have been 7.38x". If you ordered 7.400"'s you'd have a pushrod .020" longer than your engine came with.

That's why I posted it, so you as well as others will know the difference

 

Yes, I understand this. Im no guru of anything, Im your average Joe Blow consumer . And with selling websites abound, you don't have to call to order anything. The pushrods are simply labeled 7.400 or 7.425 or whatever. Now is that length that's noted on the product a tip to tip measurement or gauge measurement?

 

Pardon my ignorance, how is tip-to-tip different from "gauge" and how is "gauge" measured?

 

Check his link above.

 

Yeah, link in post #6...thanks! Never knew that...

 

Read that link to Trend's website I posted, it explains it all! The 7.400" aftermarket pushrods everyone orders is "gauge length". If you measure them tip-to-tip they are about 7.42" And that why when people say the stock pushrods were actually 7.38x", they are correct, even though tip-to-tip they measure about 7.40".