The LT-1 in my '71 Elky is getting closer to startup. Our thoughts have turned toward making sure the engine is properly oiled (primed) prior to startup, and I thought about cam-lube... and since the engine hasn't been run in a few years I decided to open the engine up and either put in some cam lube or as long as it was opened up I'd install a little hotter cam... there is an LT-4 cam that's supposed to work well.

My questions is, if I install that LT-4 cam or any other cam., will I have to reprogram the PCM? If so, is there a cam I can use that will not require me to reprogram?

To get the most from the cam you should reprogram the timing for the new cam. But that's just the begining. For a Hotcam you should also replace the springs to match the new lift, otherwise you could break a spring or float a valve. Also if the motor is stock and has some miles on it you might want to replace the lifters, and think about a set of roller rockers.

As far as a cam that would not require reprogramming you looking at something just above stock. This would also not require new hardware in the rest of the valvetrain to support it.

Here's an LT4 kit that Pace sells. LT4 Hotcam (http://www.paceparts.com/product.asp?0=243&1=250&3=791)

Thanks for your comments, Rob. I had known that if I went to a biggie-cam I'd have to get into valvetrain components... and right now we will stick to something mild.
With that LT-4 cam from Pace, do we have to reprogram with that one? I just firgured that as long as the engine was open we should put something in there, but not too much.
How's your Elky coming along?

An LT4 cam is an LT4. No difference in lift/duration so new programming would be needed. If you went with something like a Comp Cam 500 or 501 you would not really need programming as it's just above a stock cam (95 cam anyway). Engine timing is everything to really get the abilities of the cam out of the motor. Also to get the motor to idle correctly, I problem I had with the cam in mine.

What have you done as far as programming so far to get the motor running? You'll need to turn VATS, vehical anti-theft system, off for the motor to run unless you bought a VATS module. Also to adjust for the gears in the rearend and tire size.

My Elky seems to be doing well right now. I have about 8k miles on it since getting in back on the road in May. The original cam that was installed was a 218/224-lift & 528/537-duration (w/ 1.6 RRs) 114 lsa. I just could not get it idle right. I installed a Comp Cam 500 cam 206/212-lift & 513/521duration (w/ 1.6s) 112 lsa about 3 weekends ago. The idle is perfect my mileage went from 14mpg to 19+, and vacuum went from 13 to 17 psi. Best move I made with the motor so far. And it'll still spin the tire (open rear) without even thinking about it. In 2 weeks it's body work and paint time.

Don't waste the time, money or effort on the LT4 Hot Cam Kit unless you're willing to shell out the bucks for the heads and intake manifold too.
I'm running the kit and wish I had used something like Pol has.
I also program the PCM myself, and have had nothing but trouble with split BLM's at idle. It's a common problem with the Hot Cam kit. The LT4 has no EGR valve and is ground in such a way as to scavange (reversion) the unburned fuel. Without the matching heads and intake, it's a loser at idle. Now, tooling down the road it's a real screamer.

And yes, you'll have to reprogram for any cam changes, gear, and tire size changes, (if you're running a 4L60 trans.)

Thanks guys for your comments. The PCM was set up by Howell Engineering, what he called a "streetrod setup". The shop that's helping me with some of the work and installation will have to call him.
We haven't had a lot of luck with Howell according to the shop that's working with me so maybe I'll have to shell out a few more bucks and see if PCM's forLess can assist us further... I know absolutely nothingt about that stuff although I'm trying very hard to learn/understand.
Maybe we'll just leave the stock cam in there for now...
-Bill

Bill, Bryan at PCMforless is good. He did my programs for me. But he can be hard to get a reply from. A lot of people use him and he does visit different parts of the country to do group dyno tunes. Your best bet might be give the stock setup and try and see how you like it. One really nice thing about the LT1 is you get full torque almost immediatly. It's a real kick in the butt!! 8O It's funny looking at the LT1s torque 'curve', it's almost straight up and then flattens out for the rest of the rpm range. With a few bolt on mods 300hp is around the corner with it.