lt4 fd

friend has an 84 lg4 and he wants a roller cam, so aside from the retro style lifters can someone give me a few common cam sizes and thier opperating ranges and street manners along with some springs they used with them, I dont know any head flow info about the lg4 heads and im used to sizing cams for 350's, although the rule of thumb is like 5 degrees less for every 25 cubes less but ide rather make sure... thanks

BTW its a 5-speed

AutoRoc

Calling Comp Cams would be my best bet. www.compcams.com has info also. They would know what's best if you can give them the car's entire plan, useage, etc. Goodluck!

90rocz

One thing to remember is that a roller cam with the same specs as a flat tappet will make more power b/c the opening and closing ramps can be made more agressive w/o the lifters biting into the cam.
So you may not need to go as large as you would with the old set up to make good power. Plus with the computer controlled Quadrajet you'll need more vacuum. So I'd say the rule of thumb that the EFI Z's use will work, around 214/224 max and .500"lift with a LSA of about 112*(@.050")as closest. Bigger than that may involve modifying the carb like larger secondary metering rods, rejetting, resetting the pump-shot, or some ECM prom work.

lt4 fd

what sort of power range would a stock lt1 cam have in a setup like this and what sort o frange would teh 214/224 112 have on the 305?

90rocz

Actually, that mat be too agressive for the 305, I kinda read it wrong, I thought you were going to run a 350 in the LG4 car...
In that case I'd say that a mild LT1 cam would be all you'd need to wake up the 305. Something like the factory LT1 Camaro/Vette cam #12551705...201/208 (@.050") and .447"/.459(@.050") which you can get from GMPP thru
http://www.gmgoodwrench.com
Should act like a much larger cam would in a 350. That'd be my choice, and if you out grow it just add 1.6ratio rockers later.

lt4 fd

What are the specs on the stock lg4 cam for the 5 speeds?