L98 Performance Expectations?
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Joined: Oct 2005
Posts: 96
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From: Ottawa Ontario
L98 Performance Expectations?
So I've done a bunch of mods as noted below, and I am wondering how much HP/TQ I could expect from the combo. I used one of these accelerometers which told me I was running around 275 RWHP. Albeit I have a slipping clutch, maybe as a result of increased power, however HP still seems low.
Looking for opinions. Thanks
Accel Superram Plenum Ported and Polished
Accel short tube runners Port Matched
Accel Lower intake manifold Port Matched
BBK 58MM TB
Edelbrock 60879 heads including roller rockers Ported, & Milled 0.020"
Accel 26# injectors
BBK adjustable fuel pressure regulator @47PSI
No emissions i.e. no air pump or EGR,CATS
Headman Hedders, long tubes
De-Screened MAF
No cats, and 2.5" dual exhaust with x-over.
11.1 Comp
MSD Ignition
Comp Cams Duration 234/244, Valve lift 498/500, Lobe angle 112
Custom Tune By Jesse Azzato
Air Cleaner Lid opened up
Looking for opinions. Thanks
Accel Superram Plenum Ported and Polished
Accel short tube runners Port Matched
Accel Lower intake manifold Port Matched
BBK 58MM TB
Edelbrock 60879 heads including roller rockers Ported, & Milled 0.020"
Accel 26# injectors
BBK adjustable fuel pressure regulator @47PSI
No emissions i.e. no air pump or EGR,CATS
Headman Hedders, long tubes
De-Screened MAF
No cats, and 2.5" dual exhaust with x-over.
11.1 Comp
MSD Ignition
Comp Cams Duration 234/244, Valve lift 498/500, Lobe angle 112
Custom Tune By Jesse Azzato
Air Cleaner Lid opened up
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
If something is hurting the top end power numbers, its probably those heads. Out of the box they are 165cc correct? Even ported I wouldnt think they'd be quite adequate for the rest.
Drifting
Joined: May 2005
Posts: 1,370
Likes: 1
From: Raleigh NC
Originally Posted by tequilaboy
This is only a guess, depending mostly upon the heads:
300-320 rwhp
340-350 lb.ft. rw torque
Are you hitting the MAF flow limit at 255 gm/sec? If not, I'd say your under 300 rwhp.
300-320 rwhp
340-350 lb.ft. rw torque
Are you hitting the MAF flow limit at 255 gm/sec? If not, I'd say your under 300 rwhp.
My stock heads/cam '90 made 277 rwhp with a similar set up to yours...less the heads & cam of course. I'd guess your're probably slightly over 300rwhp.
Thread Starter
Advanced
Joined: Oct 2005
Posts: 96
Likes: 0
From: Ottawa Ontario
Originally Posted by tequilaboy
This is only a guess, depending mostly upon the heads:
300-320 rwhp
340-350 lb.ft. rw torque
Are you hitting the MAF flow limit at 255 gm/sec? If not, I'd say your under 300 rwhp.
300-320 rwhp
340-350 lb.ft. rw torque
Are you hitting the MAF flow limit at 255 gm/sec? If not, I'd say your under 300 rwhp.
I think I might need better flowing heads as most of everyone mentioned.
Any recommendations on the type of heads that would work with the rest of the parts.
Cheers
Race Director
Joined: May 2003
Posts: 10,749
Likes: 41
Originally Posted by UDLOOSE
I think I am, I keepm getting a code 33, high grams a second. I'll post some data from the TTS data master for you guys to review.
I think I might need better flowing heads as most of everyone mentioned.
Any recommendations on the type of heads that would work with the rest of the parts.
Cheers
I think I might need better flowing heads as most of everyone mentioned.
Any recommendations on the type of heads that would work with the rest of the parts.
Cheers
if your edelbrock's are ported. they are prob more then enough. only way to tell is get them on the flow bench.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Originally Posted by 4Ever21
look for something over 200 cc.
While I agree better flow would help, going over 200 on a 350 would be overkill. Bigger doesn't make it better !!
Last edited by mseven; Sep 1, 2006 at 08:47 AM.
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Team Owner
Joined: Sep 2001
Posts: 62,160
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Originally Posted by 4Ever21
If you build up the engine, new better flowing heads are an absolute must on L98s. 165 cc is crappy, look for something over 200 cc.