Sorry for all the posts, I would have tacked this on to a different one I've recently made, but this is kind of a topic change and I have some questions regarding it.

I have a 1986 Iroc-Z and it has the lg4 cam in it. I live in California, so if I want to stay legal, I need to have the carb eo number. I know that I can probably get by with a mild cam with or without that, but I'm gonna try and be safe for now.

http://www.summitracing.com/parts/CCA-12-388-4/

What do you think about this cam? It looks to be hotter than the 1985 cam, which was way hotter than the 86 cam. It's not listed on Summit's page, but this does have the carb number.

Also, what kind of performace gain should I see? Should it at least be as fast as the 1985 Iroc was? What will it do to my mileage? Will I have to run premium? What lifters should I get? Thanks again everyone.

 

Cam dosnt look bad everyone got a different preference of cams but i dont see anything bad about that one. One thing i will note though is that its for TPI motors and cams ground for fuel injection are not really the same as for carbed motors because fuel injection cams don't have to worry about the vacuum signal the carb receives for the fuel enrichment and stuff. Being this isnt really a very radical cam it may not be that big a deal but something to consider. You don't need to run premium gas as if you have the LG4 they dont have high compression to begin with and more radical cams will decrease compression further. Will it be as fast as the 85? That depends with what motor was equipted. If your comparing a cammed lg4 to a l69 or lb9 its hard to say but not likely. No to mention there may have been different options effecting weight ect. For example l69 cars i believe only cam with 3.73 in the rear? Long story short if your running the 150 hp lg4 and hoping to get 190-215 of the l69 or the lb9 its a bit of a stretch but its possible i suppose as i don't remember the cam specs of the LG4 but i do recall they were pretty lame. Realistically depending on specs ide expect at least 20 but not more than 40 hp. As far as lifters are concerned but that cam in a cam and lifter set it will be cheaper. All you really need is a hydrolic flat tappet lifter though nothing special. Lastly as far as gas mileage it really could go either way especially depending on your driving habits, gearing, ect. I suspect youll probably lose alittle unless you drive it hard or had really steep gears in the rear in which case you'll probably gain.

 

Thanks I appreciate your help. My car has the LB9 tpi 305, but in 1986 they came with a weak cam (lg4 cam). Sorry I should have elaborated more. My car stock has 190 hp and 285 lb ft of torque, while the 1985 has 215 hp with 275 lb ft of torque, all due to a cam change. I'd like to make mine produce at least that.

 

Oh then yea without question youll exceed the earlier 85 lb9s spec

 

Oh awesome! I forgot to mention that it has 3.23 gears I believe. I'd like to port and polish the heads as well. Port and polish and the cam should really make a jump in horsepower.