I'm installing a hot cam 525 lift in a couple of weeks into my '91 L-98, I have the free mods like everybody else along with the 1.6 roller rockers, ported intake samese runners and ported plenum like you have have already, march underdrive pulleys, straight pipes out back (no mufflers or cat's), MSD 6-A ignition box, cold air induction with K&N air filter and I have 3.07 gearing.

This is the info on the cam I'm installing:


This hydraulic roller cam "LT-1 Hot cam"

The duration at lash point in degrees (intake/exhaust) is 279/287; duration at .050" tappet lift (intake/exhaust) is 218/228; and maximum lift with with 1.6 rocker ratio (intake/exhaust) is 525/525. Valve lash is zero/zero and lobe centerline is 112 degrees.

My question is will i be able to drive decently without any extra things done to my chip (that was burnt by T.P.I.S. for the mods that I mentioned that I did) untill I can get a hold on a scanner to scan then have somebody burn one for me?

in other words, will I be fine driving untill I can get a chip burned for the cam shaft mod?
Much Mahalo's to all you folks for taking time to read and answering me this question gang!!

Aloha Nui loa (Thank you very much)

Kalani.

 

well this probably won't answer your question completely, but i'm about to install that same cam into my '91 L-98, and everyone i've talked to says there "should" be no problems. i don't have the same set-up as you, as i'm running stock everything but the heads were machined to accomodate the 1.6 rockers and i had a 3-angle valve job done also. on the other end of the spectrum, i'm also having my trans rebuilt and putting a higher stall converter in, cuz the stock one pretty much won't handle that cam.

KAM

 

Cool!! Mahalo's for the reply Kam, I had the trans rebuilt a year ago with the "good" heavy duty race stuff so I should hopefully be fine in that area, I didnt have to machine my heads at all to accept the 1.6 rollers, just had to cut out a few inner tabs of the valve covers though so the rockers wouldnt hit.

 

Expect some bogging and running lean up top. You really won't see the full potential of the cam with a TPI set-up. Trust me, experience and a HSR later....

 

When the ecm is running in closed loop, you shouldn't have much problems after driving around for a while... but when you first start up the car, and go WOT then the tune will be pretty off depending on how different the HOT cam is from the one you have now.
tibo nailed it on the head, that cam simply doesn't match with the TPI set-up. I have a crane HR with slightly milder specs: 214/220 duration, .452/.465 lift with 1.5's... anyway, when I changed from the TPI to the stealth ram, the motor really came alive after the tune.

 

A chip would be a good idea. It won't run to full potential on an SD system, but on an older MAF car I wouldn't be as worried about it.

I'd be more concerned about the heads accepting .525 lift. Anything over or close to .500 lift and you will probably need to mlll the valve guides down for more clearance. I ran a xe-269 (.503 lift) on my heads and luckily it didn't need any machining, but it was close. You'll probably have to switch to 1.5 rockers to make the cam will work on the heads without any machining. Also make sure you pick a set of valve spring that'll work with that much lift. You'll want springs with at least 110 to 135 lbs on the seat. You may be able get by with a little less spring with the stock intake though.

 

Are you reffering to the stock heads or aftermarket? My trick flows are fine.