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- - AFR 63cc PR Length? (https://ls1tech.com/forums/generation-iii-internal-engine/393351-afr-63cc-pr-length.html)

AFR 63cc PR Length?

I think I just don't speak the lingo well enough yet, and wasn't sure my results in the calculators were correct...so here I am.

The Setup:
AFR 205's (milled to 63cc's)
Cometic .04 Head Gasket
Stock 2002 C5 LS1 Rockers
AFR's 224/228/114 Cam (uncertain of base circle)

Questions:
- What PR length do I need? I want to be as precise as possible.
- Pro's/Con's If the ideal is between 2 PR lengths, should I get the longer or shorter?
- What is the base circle of Tony's cam?

Thanks in advance!!

I PM'd Tony Mamo from AFR for you. Hopefully he will answer soon.

Anyone else want to help while we're waiting for Tony Mamo? I'd like to call SDPC today.

favor the intake side of the valve on your swipe, I used 7.325 on mine with crane 1.8 rockers

Your setup would not apply to me, right?

Can you translate "favor the intake side of the valve on your swipe"?

7.400 will be fine. We just did the same setup but with 62cc chambers. You will be .006" less preload than us.

Quote:

Originally Posted by ArKay99

7.400 will be fine. We just did the same setup but with 62cc chambers. You will be .006" less preload than us.

I agree, 7.400 comps here.. 63cc AFRs :devil:

Used my same 7.4, ck sig!

Guys...

Sorry for the delay responding. Ive been buried here.

In a nutshell, AFR will NEVER recommend or quote a pushrod length. We feel it's one of those important aspects of engine building that needs to be checked if you are concerned with maximum reliability and maximum results for your individual set-up. Even with every variable the same (on paper) we still strongly recommend you check YOUR individual set-up. What if Comp ground your cam on a slightly smaller base circle because there was an issue with the core cleaning up etc.? Bottom line guys, there are many variables that effect pushrod length and AFR strongly recommends everyone check his or her own application for an ideal length. More than likely if your set-up is a carbon copy of your buddies, the pushrod length required will be the same, (of course assuming that he did all his homework as well), but the time spent to physically check your own is better than wasting a bunch of time later searching for missing HP or problems due to improper pushrod length, lifter preload, etc.

No shortcuts allowed :judge: