Hi all, im rebuildin my 305 out of my 1991 camaro z28. It's an f code with dual cats. I really want to put a new cam in my car that will give it more power and a little better lopey idle. I've seenalot of people say alot about the lt1 cam and such and at the risk of sounding realllyyyy stupid.. What engine does the lt1 cam come out of? what kind of benefits am i looking at if i used that cam (hp and tq, also driveability) and what kind of prices? Obviously it comes out of an LT1 engine but what size and years was it made?

 

Lopey idle and TPI don't mix.

But, LT1 cam and TPI will be fine.

The "better" LT1 cams are from Vettes or f-bodies. The B-body LT1's will have a better cam than your LB9, but not much.

Vettes '92-'96, f-bodies '93-'97.

 

Agreed with above.

A Vette or F-body LT1 cam is very similar in specs to an L98 350 TPI cam, but with more lift. And it's a good match for a stock or mildly modified TPI.

 

The B-Car/Vortec Truck stick is milder than a SD LB9 cam. The F/Y LT1 cam is a very slight upgrade. The PRODUCTION LT4 cam is an even better choice.

 

Check into a GM hot cam. There are few good aftermarket cams that do well with TPI.

 

Ok.. granted lope and tpi dont get along, like water and hot oil. What kind of power/ benefits would i get if i switched out my LB9 cam to an LT1 or an LT4 cam?? and if i did do a lt1 or lt4 cam, do i have to do any cylinder head work such as valves or valve springs?

 

Fast, thanks for the correction on the B-body LT1 cam. I spoke from memory without looking it up, obviously my memory had some faulty bits.

camaroman, what exhaust do you have on the car? If it's the stock single cat, don't bother doing anything until you replace the entire exhaust system.

When you do any cam other than stock, figure on needing to upgrade the valve springs. With the LT4 cam (not Hot Cam), you don't need to do machining on the heads for adequate valve travel. But, if the engine is apart, it's a good time to do it, anyway.

 

My car has factory exhaust manifolds, and im not sure of the exhaust off the headers but its not smaller than 2 1/2", it is a dual cat car but they will be gone before i put the engine back in. After the cats it is 3" all the way back to the muffler which is a flowmaster series 80 with dual exhaust. (3" inlet, 2 1/2" dual outlets) Also it has an adj. fuel press. regulator. I am having a chip burned by pcm for less as well specifically for the engine baecause its cheaper than a stock replacement. How much would I be looking at for a stock LT4 cam with stock lifters price wise?? and what kind of gains would i be looking at? I want to break 300hp.

 

Very few people on these "small car" boards know much about the B-body LT1 cam and its capability.......I do.
Even in a lighter car like an F-body, unless it has sufficient gearing and stall, it will ET better and put out within 5 peak hp of the F-body LT1 cam.
What some don't realize is that the I/E events of the B-cam result in a LSA of 111 degrees, at face value quite a bit different from the F-cam. BUT.....the actual overlap area is identical to that of the F-cam, which means it breathes just as well in the mid and low rpms. The F-cam has duration added to the exh opening and int closing sides of the lobes, giving it that 115-116 LSA number, and does little more than shift the tq and hp peaks a couple hundred rpm higher and gaining that little bit of peak hp. The bigger difference you see in factory ratings is the result of vehicle intake and exhaust system differences more than the cam.
The stock LT1 in my Impala with nothing more than 1.6 rockers and better valvesprings dyno'd 309 rwhp STD and ran 12.3's @ 107+ mph in a a 3900 lb car. Very few stock LT1 F-body's do any better, even at lighter weight.