Hey all, I have a 85 f150 4x4. I recently pulled the 351w to freshen it and being the young feller I am and having deep roots in drag racing I decided to give it a little more kick in the pants. Problem is it seems to have less power than it did before the rebuild. Here is a list of mods. Block bored .030 over. New rings,pistons,crank main rod and cam bearings, heads surfaced (factory heads), new valve springs,lifters,pushrods,rockets. Edelbrock performer intake, msd pro billit vacuum adv dist. Msd 6A ignition box, and hedders. I also installed a new cam. I wanted the comp cams extreme 4x4 but my parts man talked me out of it and got me an aftermarket cam "designed" after the old mach 1 mustang cam. also installed quick fuel technologies 650 hot rod series carb. The motor just seems to be lazy. I set cam in on 0 and I think this may be part of the problem. This motor should be producing 350 HP but its worse than the motor before the rebuild. Any advice/

 

I would look at the timing.

 

Yeah timing sounds right

 

Thanks fellas. I took a look at the timing and I've got a few questions. I set base timing at 8 degrees atdc. With vacuum off and plugged I get 24 degrees @ 3000 rpm. Everything I've read says to do it this way. So that gives me 32 degrees total timing. Right where I want to be. But I knew hooking vac advance up would advance beyond this point. Sure enough timing goes to 46 degrees. I think this is way too high but I can't retard total timing with vac adv hooked up to 32 degrees without sacrificing base timing. That will put base to around 2 to 4 degrees btdc. Any thoughts?

 

You should have no vac at idle at hose from carb, if you do you have the vac hooked up at the wrong port on the carb. I did the same thing.

 

Bump Any updates?