Cam question
Thread Starter
Instructor
Joined: Sep 2004
Posts: 122
Likes: 0
From: Salt Lake City UT
Cam question
i got the motor out and was wondering what the specs are on the stock cam. also i'm looking into a comp cams in the TPI section and was wandering if that .450in-.480ex was a decent cam to get?
Burning Brakes
Joined: Nov 2003
Posts: 914
Likes: 1
From: Redding Ca
I had a Hyd Roller Comp Cam (112 degree LSA)with very similar
(maybe even idential) stats in my '87 Pontiac GTA with 383, TPIS intake manifold, Large tube runners, ported plenum, 52mm throttle body. The car weighed 3600 with driver with 3.27 rear end and 700R. With drag radials it ran 13.35's @102-104, with 1.86 60-ft times.
The cam idled smooth (faint lope) got good gas mileage and made great low and mid range power, but fell off at 4800rpm's. It passed the bi-annual Cal smog test with flying colors. It is a great street/daily driver cam, but you might want more at the drag strip. I drove that configuration 100,000 miles when I sold it and it was still just as good as the day I started it.
(maybe even idential) stats in my '87 Pontiac GTA with 383, TPIS intake manifold, Large tube runners, ported plenum, 52mm throttle body. The car weighed 3600 with driver with 3.27 rear end and 700R. With drag radials it ran 13.35's @102-104, with 1.86 60-ft times.
The cam idled smooth (faint lope) got good gas mileage and made great low and mid range power, but fell off at 4800rpm's. It passed the bi-annual Cal smog test with flying colors. It is a great street/daily driver cam, but you might want more at the drag strip. I drove that configuration 100,000 miles when I sold it and it was still just as good as the day I started it.
Last edited by GeosFun; Feb 9, 2005 at 04:31 PM.
Burning Brakes
Joined: Nov 2003
Posts: 914
Likes: 1
From: Redding Ca
Oh, and I changed converters to one that stalled around 1800 because the engine idled poorly/died a lot at stop lights with the tight stock converter. 
Last edited by GeosFun; Feb 9, 2005 at 05:25 PM.
Thread Starter
Instructor
Joined: Sep 2004
Posts: 122
Likes: 0
From: Salt Lake City UT
i think the cam is good up 5800, but thats is it 13.3. i was hoping for something quicker. i'm polishing the heads and a bore of .030 over. with me stock i ran a 13.9 in stlouis
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
I believe the specs on your '91 L98 cam are the same as those in my '88: 1.5:1 - Lift=.410/.423, Dur=211/219@.050” (int./exh.), LSA=117
That cam wouldn't be too bad with 1.6:1 RRs and Comp Cams 981 springs.
Actually with my stock cam, 1.6:1 RRs and the siamese intake base my L98 pulls well to 5,800rpm.
If you pocket port the heads, get a 5-angle valve job with larger valves, etc, that cam should pull to over 6k RPM with some intake mods.
Combine the heads & cam with exhaust and a few other mods and you should be in the 12s in decent weather.
That cam wouldn't be too bad with 1.6:1 RRs and Comp Cams 981 springs.
Actually with my stock cam, 1.6:1 RRs and the siamese intake base my L98 pulls well to 5,800rpm.
If you pocket port the heads, get a 5-angle valve job with larger valves, etc, that cam should pull to over 6k RPM with some intake mods.
Combine the heads & cam with exhaust and a few other mods and you should be in the 12s in decent weather.
