I have read all of the recent post about camshaft selctions. It seems like most people go with the CompCams 255DEH. I decided, after talking to a tech at CompCams, to go with the CompCams XE256H, an "Extreme Energy" model. Was I in error? What do you think? My truck will be used for Street driving only. It is a 78 F-250 Supercab 2wd. Has a 400 with a c6.

The carb question I had was, what carb should I run on this truck? I first bought the intake and carb and installed it. the carb was an Edelb. 750 cfm. I didn't know anything about cfm at the time, and figured more was better. Wrong! I want to get a carb around 600 - 625 cfm, what carb would any of you recomend?

Now for the fun stuff..
I had the tranny rebuilt with a mild shift kit
The Heads were machined to factory specs
Replaced all bearings in lower end
Replacing Stock cam with XE256H
Installing a double roller Timing chain and gears straight up
MSD ignition with MSD distributor
Installed a performer 400 intake without EGR
Installing a new carb
Have Headman headers with 2.5 dual exhasut out the back, no cats
New starter, water pump, alt, Powers teering pump, Fuel pump

Any advice, or any comments on the build would be nice, just keep in mind that I am not interested in Replacing the pistons. The guy that had this motor brfore me had the bottom end rebuilt. I just installed the new bearings for the heck of it.

Thank you

 

good cam choice imo...a little more lift. i don't know if they have been legitimately compared on the dino but i like the way the xe's look. I have a holly and edelbrock. i like the edelbrock 600...easier.

 

Alright since somebody brought this up, I'm in the beginning stages of a rebuild on my 400, so basically i'm making my wishlist for the parts thanks largely to all the advice from everyone here. anyhoo i was at summitracing.com looking at the 255DEH and this was their write up on it...

"These Dual Energy camshafts from COMP Cams have more exhaust duration and lift than intake. They are designed for applications where a slight sacrifice in low-end power is acceptable for an increase in mid and upper-range rpm horsepower. These cams are ideal for use with restricted exhaust port cylinder heads, or applications using a full-length exhaust system. "

I thought this cam was supposed to be perfect for low end power, so i guess my question is do they not know what they are talking about or is something like the XE256 (or any other cam for that matter) going to be better for low end torque?

 

comps catalog does not hint at low end sacrifice and there is none as far as i know until you hit the 262-265 + duration. The exhaust duration helps through the curve and helps economy as well.

Summit has that written for at dual energy cams as a group and it does not apply to the 255- might in the 302 or windsor - not sure.

How much are you looking to spend on your build...I've done a lot of research and think i have a great parts list- higher end.

 

I wouldnt hesitate throwing the 750 E. on their until you get another carb... I been runnin a 750 on my lil 351M for a few years. Something around 600+/- would probably be better, but it seems to work just fine for me, and I rarely get into the secondaries, heck I barely touch the pedal for the most part. Actualy got better mpg after some tuning than the stock carb too.

 

I appreciate any input, however the budget is limited ($2,000) because of school loans and my '07 mustang. So right now im working on interior motor parts, machine work, timing etc. If you had prices and where you bought it that would be a huge help. Right now i just searching Tmeyer obviously, summit, jegs, northern auto, so if you have better places i 'd like to hear that too.