I have a 85 iroc that I want to add a cam to. What is the biggest cam that I can use without messing up the computer and having to burn chips for? Also if I had 1.6 rockers would that mess with the computer if I used the stock cam or aftermarket .
Thank you

 

the 1.6 wont affect the comp at all, as for the cams look in summit/jegs for cams for comp controlled cars.. i beleive comp cams has the XE (extreme energy) series, some of the bigger ones may require custom tuning, but IMO those ones would be way too big for your application anyways, maybe someone else with more cam experience can chime in here

 

i had good luck with the comp cams 12-404-4 quite a few years back it was well mannered however it does need a 2200-2500 stall speed but this cam provides very strong bottom end,now i am an all roller guy!!!!!!!!

 

I'd say stay around 212/219 duration. Rockers should be find, providing your springs can handle the lift of the cam.

To find your lift with 1.6 ratio rockers, divide the 1.5 ratio lift by 1.5, then multiply that number by 1.6, this is the lift with 1.6 ratio rockers.

 

anything you modify in the engine u should have the PROM tuned accordingly...But you can get away with mods and stock chip but you motor will never run at its peak power. As for adding a cam I think the biggest cam u can get away is the LT1 w/ 1.6's. anything more and the computer wont know what the heck is goin on.

Jason

 

The Lt1 cam won't work in the 85 because its a roller cam. You need to find a hydrualic cam that will work with what you have. I would call crane and ask about their powermax computer cams. I also have an 85 TPI and i just got my crane powermax computer controlled cam, its the 2040 series ( duration @ .050 210/ 216, lift 440/ 454 ). This cam would def. be an improvement from the stock 85 cam, if your car is stock i wouldnt go much bigger than the 2040 series, but the 85 cam is a decent cam to begin with.

 

That 2040 looks pretty nice IMO. For my 86 IROC's 305 TPI I went with the 204/214 dur @.050 with .420/.442 lift cam that Summit, Crane (2030 I believe), etc all make a version of. It works fine with the stock programing and was a big increase over the peanut cam the 86 was saddled with. It's not a whole lot bigger than the 85 cam though. Knowing how well this one works I'd step up to something right in that 2040's range if I did it over again, it has more aggressive lift and just a little more duration. Perfect IMO for trying to work with alot of the stock stuff...