i just bought a lt1 out of a roadmaster and the guy swapping the motors for me offererd me his zz4 cam that he had on his brand new 355 zz crate engine.. its never been ran he just took it out because he wanted a bigger one.. he offered me that and the springs.. would it fit and run fine on the lt1? and what kind of cam is it.. mild? or what.. Thanks

It's an OK cam. Will make more hp than the stock OEM LT1 cam, but the problem is, it will do it with a 112 lobe center whereas the LT1 cam uses a 115 lobe angle. Now, 3 degrees doesn't sound like much, but it is. What the 112 will do is transfer some hp (it's really torque) up into the higher rpm ranges. Problem is, the LT1 with its roller lifters is a comparatively low rev engine, but will be reliable to around 6,000-6,100 rpm with the zz4 cam. You can use the stock rocker arms, or go with 1.5 roller rockers or even 1.6 roller rockers for added kick. However, without proper porting and polishing of the heads, you won't experience the true potential of the cam. Also, this cam will work fantastic up above 6,500 rpm, but it will only get up there if you install 1.6 roller rockers, or even 1.5 rollers (the stock stamped steel rocker ams will burn out much above 6,000 rpm). However, you should install the AFR Hydra Rev Kit to keep the lifters from bouncing on the cam lobes. The rev kit will keep the lifters on the lobes till well over 6,500 rpm and make the engine an absolute killer on the street. I would use 3.42:1 rear gears or better with this cam due to loss of low end torque. You should not need to reprogram the PCM if the engine is still comparatively stock, but it wouldn't hurt. If you port and polish the heads, use 1.6 roller rockers, there is a possibility that one size larger injectors will be needed and that WILL mean a reprogrammed PCM. The heads should be ported to around 200 cc (intake) to no more than around 210 cc. The stock heads are around 170 cc.

Horsepower: If you use 1.5 roller rockers, the stock injectors can be used and the PCM won't have to be programmed. Expect around 15-20 more hp than the LT1. With porting and polishing, add 30 hp. With 1.6 roller rockers, add at least 15 hp to the numbers throughout the rev range and more at high rpm. With an AFR Hydra Rev Kit, and the additional rpm that can be used--add another 15-30 hp throughout the rpm range and expect to see more than 100 hp less fall off at 6,500 rpm. That means the engine will be making a whole H3LL of a lot more hp! Maybe as much as 400 with an additional 30 hp if you do all the mods together. If the car is an automatic, use a high stall converter--no more than 2,800 rpm, but you can get away with a 2150. With the auto, guys are reporting that 3.70:1 rear gears are great. If the car has a manual, the 3.42 will work, but something around 4.10 is better for max acceleration. All the mods will get the car into the 12s in street trim.

Hope this helps,