Pushrod Length??

Custompony, I had the same question not too long ago. I found out you have to use and adjustable pushrod to figure out what length you need. See the link below to see what I am talking about, good luck.




COMP Cams Hi-Tech Pushrod Length Checking Tools - SummitRacing.com

custompony said:

I'm about to start building my 302 stroker and I'm confused on pushrod length. I have a Probe 331 Street Fighter Kit, 14855-STD-SF-F331. The cam is a Comp Cams 35-000-8. Ported/Polished heads with 1.72F Scorpion rockers. Any engine guys out there that can help me out or put me in the right direction?

Also, any top of the head horsepower estimations? Thanks.

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Hi,
I'm running a 331 stroker with a .040 overbore. First, I'll congratulate you on even knowing to check P/R geo. It is as important to get this right as degreeing a cam. As the other respondent noted you need a set of adjustable Push rods. Additionally, you'll need a set of checking springs. These are lighter and are installed in place of your normal valve springs, usually in #1 cylinder position. Also, it helps to monitor this process with the intake removed. Using checking springs if running hydraulic lifters, insures the the plunger does not depress and provide a false measurement.
You'll also need, either a sharpie or "bluing" ink to coat the tip of the valve stem. There is a mountain of detailed information on the net about checking P/R geo. I see were you are going with 1.7 ratio rockers. What makes you think you need to run this ratio? I'll assume you'll be checking P/V clearance.
Regarding estimated HP? Given the information mentioned, you cannot accept with any validity, any "gestimate" of potential HP. What heads, valve size, carb size, header type, cam events, ..........are you running?
I'll offer as potential, my 333 (331/.040 over) makes 392 RWHP at 5900 Rs and 400 RWTQ @ 4400. I'm running TW 170 heads, roller rockers, 10.6 CR, dual DCOE Webers, Performer RPM, CI billet hyd. roller cam, TRI-Y headers into 2.5" system, custom curved dizzy etc. My engine is built as a street warrior and building low end torque.
Good Luck with your project.