[newchevyman]

I purchased a pickup from a "friend" that has a problem.

About a year ago I helped put a much too large cam in a basically stock 350 in this pickup.

Here are the specs:

1977 GMC shortbed, about 3800 lbs. 3.42 ratio 10 bolt and T350 with TCI converter, probably about 2400-2500 stall with this engine

350 bored 30 over with what appear to be stock pistons

Junk heads with 76cc chambers, "Z28" valve springs, new standard valve job

Performer RPM intake with Edelbrock 600

Headers through 2 1/2" exhaust

Comp cams 230/230 @.050 .480/.480 lift
Pretty sure this is way too much cam, truck is pretty much a dog.

I have a set of aluminum Corvette heads with (I Think) a 58cc chamber. Would these help cure the junk-heads-can't-breathe-and-low-compression-with-too-big-cam blues?

Thanks!

 

[Max Keith]

heads

It sure wont hurt you. As far as the cam goes, it may be marginally a little too big for the gear you are running but the higher stall is helping in that area. Probably a better choice in cam would have been one in the 220-225 degree range. Putting the better heads on your engine should also help pick up some of the lower end grunt you may have lost with that cam. Were it me, I would slap on the heads, drive it for awhile and see how it performs. The 230 degree cam is about as big as I would go in a street engine in a vehicle that weight anyway. One nice thing is that the better the head is at flowing the less cam you need. I would bet odds on that the 230 cam is more than your stock "junk" heads can really work with, in that they arent capable of flowing what you really need in ports for a cam that size.

One thing I would recommend with the new heads. Invest in a set of 1.6 rockers and pick up about .032 " increase in lift. That would be helpful as well. While putting higher lift rockers on your engine can look disappointing from the peak horsepower gains, it is well documented that adding them can add as much as 2-3 hp at any and all registration points in your power curve. IE: if you had a dyno read out in 500 rpm increments, you would see a 2-3 hp gain at all of them, so if you are looking at a 6000 rpm engine, you can honestly say you picked up 24-36 hp through out your power band. And thats not just at the peak.