Thread: lt4 hot cam on carbed sb?

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Has anyone put an lt4 hot cam in a carberated engine or seen one done? I hang out with some third gen guys who are always talking about this cam. I have a factory roller block and this will be a daily driver so i was thinking maybe it would make a good, strong, streetable candidate for my 64 stepside.

Originally Posted by josh bichard

Has anyone put an lt4 hot cam in a carberated engine or seen one done? I hang out with some third gen guys who are always talking about this cam. I have a factory roller block and this will be a daily driver so i was thinking maybe it would make a good, strong, streetable candidate for my 64 stepside.

I don't know that it would be any better than a thousand other cams you might use for the same purpose. Here's the skinny on it though.....
Duration @0.050" 219/228
Lift w/1.5 rockers 0.492"/0.492"
Intake centerline 109 degrees ATDC
Exhaust centerline 115 degrees BTDC
Lobe separation angle 112 degrees
Intake opens -0.5 degrees BTDC
Intake closes 39.5 degrees ABDC
Exhaust opens 47 degrees BBDC
Exhaust closes 1 degree ATDC
Using the operating characteristics from a similar cam grind.....
RPM power range 1800-5800
Good idle, daily useage and off-road, towing, performance and fuel efficiency. 8.75 to 10.75 static compression ratio advised.
I might use a spring that provides ~125 lbs on seat and ~350 over the nose.

I can tell you this, I like the sound of the LT4 hot cam. I put one in my wife's '95 Camaro with headers and a cat back Magnaflow and it sounds real nice. Even passes smog like nobody's business. I would bet it would sound just as good or better on a carb'd motor. When I build my '31 Tudor I'm gonna run an LT1 with the LT4 hot cam in it. I parted out a Camaro and got a good LT1 and T56. It will make a real nice hot rod setup.

Keith

Yea it will, my friend has a 92 rs. we got the iron headed lt1 out of a wrecked buick roadmaster and he found a six speed with all the plumbing for 400 bucks. We paid 150 for the car, then sold the 4l60e for two hundred; So now he has a low 14 second car and 20+ mpg for next to nothing. he wants to run the hot cam but is affraid his springs wont handle it so hes debating between getting his heads machined or just finding some f body heads.

I bought the rocker and spring kit that GM sells just for the LT1. It's a drop in and go deal. The rockers are self aligning so no guide plates are required. The stock springs will suffice, but they will not put up with the added rpm the cam will give you. If you go fuel injected, you may want to replace the knock module with an LT4 module in the computer if you decide to run roller rockers. I haven't got my computer reflashed or replaced the knock module yet. Maybe this winter.

Keith

If you use rail rockers, make sure there is no contact of the pushrod where it comes through the head through the entire valve lift. You don't want two systems of guidance.