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Discussion Starter · #1 ·
I got a few 4 bot main 350's and am building one for my rat rod. I am looking at cams. I will tear the motor apart an have it machined but was wondering about the heads. They are 881's. I read the specs and basically the same as 882's with a larger valve. 2.02 and 1.60. 76cc chambers. I want a nasty cam and lots of lope. I have built a few sbc's but I want this to be the nastiest. The one on my nova had a 292 mega grind isky cam but had built 461 heads.(hardened seats and new springs with a 3 angle valve job) I was wondering what I could do with these heads. I am open to having them milled down and changing the springs, but not much more than that. basically what kind of cam will max these heads out with out causing drivability issues, Its a 3 spd manual, and sill have 3.73 gears.
 

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Low compression and higher flow calls for a modern grind. We prefer Comp Xtreme Energy cams, but you'll get mixed reviews here. Lunati "VooDoo" grinds are also very good in this type of build. UltraDyne cams are still floating around "out there", but I wouldn't base a "build" on one unless I had it "in hand".

If your budget can stand it, a solid roller is always the most effective type. Comp offers some very nice street-designed rollers for the small block. Without significant port work, I would keep intake duration under 240-ish @ .050. With the large chamber, more exhaust duration is called for, as well, 4-6 degrees.

The flat tappet cams work very well, too. The XE262H is VERY popular with the "mild idle" crowd. It makes low-end and vacuum is high. XE274H is a strong runner up to about 6,200 and has a nice "lope". In between is XE268H, which is popular with the manual-trans crowd. It's just a tad too much for a stock converter, but doesn't do a good converter "justice".

We've used the solid flat tappet XE grinds as well. Only a couple of 350s, but they run real nice. The 461 Pontiacs LOVE them!

Again, you'll get mixed reviews, but I feel hydraulic rollers are a bit of a waste unless you have a "roller" block. The retro-fit lifters aren't as nice as the factory units, and the solids are a little less expensive and make more power.

Make sure the heads have screw-in studs and guideplates installed.

FWIW

Jim
 

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Discussion Starter · #3 ·
thanks for the help, I was expecting a flame for using **** heads! I priced out a motor build and its looking pretty good. I havent even torn the motor down yet. The other motor I have has 882 heads that are worked??? not really sure what that means, I am not dropping the money on bench testing them. I am thinking if the block and crank come back and all is good I will just buy a set of nicer heads because the motor is the focal point of a rat rod. Maybe someone on craigslist will be selling some 64cc afr's for like 200 bucks!!!
 
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