A Big cam in a 400... uh NO! I guess I dunno what you call a big cam, but I would say a 268 is more then enough came for a stump puller 400 or 406. The nice thing about the 400's is the light weight small block and the fact that is basically is all torque! Now if you think you are gonna be able to get the rev's for a big cam you are crazy! The stroke is way too long and w/ stock internals I'd say a 5,000 rpm is a nice redline for a street driver truck. Depending which make of cams you go with you can play w/ the cam to give you more torque in different areas... a 264 would yeild excellent stump pulling abilities. Now if you want mundo cam and revs (in a 4x4? Is this the car craft nationals LOL
) then you would be better off w/ a 383 or for the rpm screamers the destroked 377.
Cylinder heads are gonna big your biggest investment and second most important choice IMO. You ideally want a 190 or so port sized head. My tops choices are also the the AFR 190's. AFR is probably the best small block head maker IMO. Edelbrock's new Vortech style heads... the e-tec are also awsome. They will out flow GM's fast burns by about 20% from what I've heard, but they are aluminium. For cast heads the Vortechs would work for a torque monster and also a head like the sportsman II's would be excelent bang for the buck, although they have a 200cc port which would tend to be a bit large for a torque application.
Exhaust... 2 and a half tops. Unless you have the larger ports and cam design to vent the exhaust gases all the 3 inch exhaust will do is make lose back pressure. One of the torquiest cars I have ever seen is a 91 Camaro w/ a 406 with a custom sigle pipe exhaust that measures 31/2". It's a daily driver that flys, pulls wheel stands at the track w/ cheater slicks and just a blast to ride in. Exhaust seems to be another area misunderstood... it isn't just pipes and the headers... it is valve size, cam specs, etc. The right motor combo can max out even 3" duals.
Now if you want a budget terror just go w/ a 350 or 355 w/ a 260 or 262 cam and some vortech heads and it will easily put a smile on your face
compared to the old wheezer motor. You'll make less torque but would save some $$$ and depending on your truck's setup you may save some broken axle shafts, u-jt's, etc.
Obviously there are many theories to engine design, and since I have wandered over to the 4x4 ranks from the strip, the number one thing I have seen is building a motor for a hot rod and hp rather then torque and a healthy idle to 4 or 4500 rpm pulling range.
-Mikey
1987 Chevy K5 Blazer- 350 TBI
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