The Stovebolt Site Forums The Shop Area The HiPo Shop An Early Christmas Present / Offy Intake & Fenton Headers

I have recently been given an offenhauser intake and fenton headers. I hope to install them on my Chevy 261 which is bored 0.030 over with a stock cam. I do have a set of Rochester Model Bs that I plan on installing on the intake. I am assuming that I will need to rejet the carbs and possibly install lighter power valve springs. The main jets in the carbs are currently 63s; I am assuming that the springs are stock. I am not sure what size main jets and power valve springs I should use. Anybody got any recommendations?

In addition, I do plan on providing heat to the offenhauser. I am still not sure if I will be using water or exhaust heat. It seems as if water heat would be less destructive to the offenhauser intake since I am afraid that the corrosive exhaust gases would eat it up. I have the threads concerning manifold heat. I don't think that the corrosive gas issue has been addressed. I apologize if I missed it.

Thanks in advance for any advice you can offer.

Jon

I forgot to mention that the intake is a dual carb intake.

Jon

you can get a predrilled carb heat plate from langdons stovebolt, i plan to get one for my conversion i did this summer. i can't believe the differance the fentons with dual exhaust made to my power, nothing spectacular but enough more so i don't have to change gear rations just yet. i have a 54 with 235 with dual carbs, the carbs idid 5 years ago and it still couldn't hardly pull it self. 273 nova rearend is part of the problem. ron good luck it was worth it to me.

WE b Old:
Thanks for the reply. I glad to hear you were happy with the results. I hope to get similar results from the 54 261.

jon..I also installed the same set-up you mentionned on a '58 235. Couple of "lessons learned"...avoid Rochesters if possible...Langdon's Stovebolt sells properly sized Carters for that set up...I started out with the Rochesters and suffered with them for a couple of years (leaking/loading up/basically untuneable)I switched to Carters and all my problems were solved. (Carters are not expensive!).
The manifold heater(water) is a nice addition and easy to install.
Good luck.

Thanks for the advice Steve. I have sent Tom Langdon a message regarding my set-up. I will ask him about the Carters when he replies. Did you use Carter YHs or W-1s?