Offenhauser DP to Clifford heating difference.

F-250 Restorer

Famous Member
I changed from a Offy DP to a Cliff. intake. Both have the engine coolant flowing through them. I changed the intake and engine a couple of months ago, so I've been playing with/adjusting the choke to get it right. However, with the Cliff. intake, using the same holley carb as was on the Offy, I find that I have to warm up the engine for five minutes or it wants to die when I try to accelerate. With the Offy there was no problem. Once the engine is warm, it runs well.



Famous Member
I've never had that problem with my Clifford. As far as I know, the Offy is built to use the factory manifold type of heat, whereas the Clifford has a long water jacket on the bottom of the manifold.

Did you readjust the carb due to the difference of the DP and the open Clifford?


Well-known member
I was going to suggest carb tuning as well. My Clifford doesn't seem to make a difference with or without water heat, very small if at all.

Maybe it needs a fast idle?