If I remember correctly the Hot cam didnt come in the production LT4 cars. Right or wrong? If not, what cam did they have, was it the LT1 cam?
Anyone know for sure?
Ron

 

Slightly bigger cam for the LT4. I have seen a couple of different specs, which differ slightly. These below are often quoted.

LT4|LT1
203/210|205/207
.476/.479"|.447/.459"
LSA: 115|117

The LT4 cam is also reputed to be ground with an extra one degree of retard compared to the LT1, though I can't give a source for this info and really don't know if it's so.

Rich Krause

 

You are correct, the LT4 did NOT come with the Hotcam. Like Rich said, I've seen several specs for the LT4 stock cam, but there are all right around what he posted. The big difference in the LT4s was not the cam, but the heads and 1.6RRs. I would be that there would be absolutely zero gain in just swapping an LT4 cam into an LT1.

 

Not sure if it's true, but I had my LT4 SS at Chevy Vettefest last year, and Scott Settlemiere saw it and we got to talking.

One of the things he mentioned, is the LT4 F-body's got the LT1 camshaft, (along with injectors, egr, PCM), because it would not pass emissions certification with the LT4 cam.

 

I've heard this one other time, but all the other info I've found says it was just the LT1 ECM and injectors. Does (did) Scott work at SLP?

Either way, with a modified LT4 program in the ECM mine put out 302RWHP, and we're pretty sure we can still pick up another 5+HP with some fine tuning on it. If it does have an LT1 cam, this would just go to show how close the two cams actually are.

 

I was looking around gmpartsdirect.com last night and you can buy the stock lt4 cam and i think it had the specs on it. Id check but i dont have enough time right now.

 

Here's a good comparison, I've included lift with both 1.5 and 1.6 rockers so you can get a better idea:
LT4: 203/210, 446/449 lift w/1.5, 476/479 lift w/1.6, 115
94/95 LT1: 201/208, 450/460 lift w/1.5, 480/490 lift w/1.6, 117
96/97 LT1: 205/207, 447/459 lift w/1.5, 477/489 lift w/1.6, 117
Hotcam: 218/228, 492/492 lift w/1.5, 525/525 lift w/1.6, 112

As you can see, the LT4 stock cam is actually right between the two LT1 cams on intake, and just slightly above on exhaust, but has noticeably less lift when compared with the same ratio rockers. Anyway, I really don't see enough difference in any of the stock cams that it would make a noticeable difference going from one to the other on the same engine.

 

Thanks, I'm wanting to go to a different cam when I rebuild the engine but I dont want to kill my gas mileage since it is my daily driver (100 miles a day). I havent decided what to do yet but it doesnt look like the LT4 cam would do anything for me.
Ron

 

As long as you have a good tune, I don't see that going with the Hotcam or even something larger will really kill your MPG.

 

Let me clear up why I say the above. On my 95 Formula I had, I put in a 214/214, 540/540 lift w/ 1.6 RRs cam, installed 4.10 gears and did tuning and GAINED 1-2MPG for both city and hwy driving.