Numbers low for Combo?
Thread Starter
CF Senior Enthusiast
Joined: Nov 2005
Posts: 136
Likes: 0
From: Calgary Alberta
Numbers low for Combo?
Just finished off the Stage II Procharger install on a 98 Vert. Running 7-8 lbs boost with a 3.85 pulley, LS6 intake/80 mm BBK TB, LG street Series/no cats and AIS meth system. The car is running great but is outflowing the stock LS1 MAF which will be slated for replacement in the spring along with a FAST intake and 90 mm TB.
The meth is set to come on around 3 lbs. Final numbers are 479 RWHP and 448 RWTQ. Timing at WOT is around 18 deg. The motor is a stock LS1 otherwise. AFR is almost dead on 12.
I feel these numbers may be on the low side for the combo. Thinking they should be in the low 500's for RWHP and around 480 + for RWTQ. Is the stock heads/cam combo the culprit?
Any input from the FI experts would be greatly appreciated.
The meth is set to come on around 3 lbs. Final numbers are 479 RWHP and 448 RWTQ. Timing at WOT is around 18 deg. The motor is a stock LS1 otherwise. AFR is almost dead on 12.
I feel these numbers may be on the low side for the combo. Thinking they should be in the low 500's for RWHP and around 480 + for RWTQ. Is the stock heads/cam combo the culprit?
Any input from the FI experts would be greatly appreciated.
Melting Slicks
Joined: Oct 2006
Posts: 2,574
Likes: 3
From: Fredericton NB
I just had the Vortech S trim installed on my 01 Z...
The numbers were 600/512 with a custom grind cam, fast 90/90, ARH's, stock heads and no meth....
I'm a FI noob so I'm not really qualified to make comments on your installation and set up....but the #'s do seem a bit low...
I'll sit back and
on this one.....
What kind of dyno was it ??
Bubba.
The numbers were 600/512 with a custom grind cam, fast 90/90, ARH's, stock heads and no meth....
I'm a FI noob so I'm not really qualified to make comments on your installation and set up....but the #'s do seem a bit low...
I'll sit back and
on this one.....What kind of dyno was it ??
Bubba.
Last edited by BUBBAS 01Z06; Nov 2, 2008 at 04:58 PM.
Melting Slicks
Joined: Sep 2005
Posts: 2,521
Likes: 146
From: Watertown CT
Is this on an auto?
What type of Dyno?
If an auto, it seems a bit low. If stick, I think it's low.
When you said the AFR is dead at 12, 12:1 right? Is that on the Meth? To me that is lean while on Meth. Most will say the basic rule is a point lower while on meth, so if you were to run 11:1 on gas, add meth, you should be 10:1.
Just my opinion though.
Dan
What type of Dyno?
If an auto, it seems a bit low. If stick, I think it's low.
When you said the AFR is dead at 12, 12:1 right? Is that on the Meth? To me that is lean while on Meth. Most will say the basic rule is a point lower while on meth, so if you were to run 11:1 on gas, add meth, you should be 10:1.
Just my opinion though.
Dan
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
A good blower cam will make more difference than a set of ported heads. ECS cam is very popular. I have the A&A cam and love it. Arun at CDNperformance has good cam grinds as well. There are many vendors to choose from. EPP, Dallas Performance, Canadian Performance, A&A, and ECS. Give one of them a call and they will determine the best cam for your driving style and performance desires. 
Thread Starter
CF Senior Enthusiast
Joined: Nov 2005
Posts: 136
Likes: 0
From: Calgary Alberta
Thanks for all the info guys. Sorry, I did forget to include that it is a Mn6 with stock sizing wheels and that the car was tuned for meth with the AFR being 11.8 - 12.0:1.
The car previously made 337 RWHP and 351 RWTQ with LG headers, X-pipe, no cats, LS6 intake, 80 mm BBK TB and a VR2 Vararam.
Both the runs prior to and after the supercharger install were made on the same Dynojet for comparison.
Is it possible that out flowing the stock LS1 MAF is killing the top end HP?
I will post a dyno graph of the run as soon as I figure out how to copy it.
The car previously made 337 RWHP and 351 RWTQ with LG headers, X-pipe, no cats, LS6 intake, 80 mm BBK TB and a VR2 Vararam.
Both the runs prior to and after the supercharger install were made on the same Dynojet for comparison.
Is it possible that out flowing the stock LS1 MAF is killing the top end HP?
I will post a dyno graph of the run as soon as I figure out how to copy it.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Melting Slicks
Joined: Sep 2005
Posts: 2,521
Likes: 146
From: Watertown CT
Thanks for all the info guys. Sorry, I did forget to include that it is a Mn6 with stock sizing wheels and that the car was tuned for meth with the AFR being 11.8 - 12.0:1.
The car previously made 337 RWHP and 351 RWTQ with LG headers, X-pipe, no cats, LS6 intake, 80 mm BBK TB and a VR2 Vararam.
Both the runs prior to and after the supercharger install were made on the same Dynojet for comparison.
Is it possible that out flowing the stock LS1 MAF is killing the top end HP?
I will post a dyno graph of the run as soon as I figure out how to copy it.
The car previously made 337 RWHP and 351 RWTQ with LG headers, X-pipe, no cats, LS6 intake, 80 mm BBK TB and a VR2 Vararam.
Both the runs prior to and after the supercharger install were made on the same Dynojet for comparison.
Is it possible that out flowing the stock LS1 MAF is killing the top end HP?
I will post a dyno graph of the run as soon as I figure out how to copy it.
Dan
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Just finished off the Stage II Procharger install on a 98 Vert. Running 7-8 lbs boost with a 3.85 pulley, LS6 intake/80 mm BBK TB, LG street Series/no cats and AIS meth system. The car is running great but is outflowing the stock LS1 MAF which will be slated for replacement in the spring along with a FAST intake and 90 mm TB.
The meth is set to come on around 3 lbs. Final numbers are 479 RWHP and 448 RWTQ. Timing at WOT is around 18 deg. The motor is a stock LS1 otherwise. AFR is almost dead on 12.
I feel these numbers may be on the low side for the combo. Thinking they should be in the low 500's for RWHP and around 480 + for RWTQ. Is the stock heads/cam combo the culprit?
Any input from the FI experts would be greatly appreciated.
The meth is set to come on around 3 lbs. Final numbers are 479 RWHP and 448 RWTQ. Timing at WOT is around 18 deg. The motor is a stock LS1 otherwise. AFR is almost dead on 12.
I feel these numbers may be on the low side for the combo. Thinking they should be in the low 500's for RWHP and around 480 + for RWTQ. Is the stock heads/cam combo the culprit?
Any input from the FI experts would be greatly appreciated.
Got your PM too!
The numbers seem a little low for your set-up! so here goes:
1. The stock MAF - If you have not changed to the 2 BAR MAP sensor you need to - our MAF's do not have enough table for the SuperChargers amount of flow.
AC DELCO Part# 213-1631 or GM Part#12580698
2.A4 ? Torque Converter - Stock or Stall?
3. Which rear gears? MN6 3.42's or A4 with 3.15's or 2.73's
It should be over 500 RWHP at least! We did one on my buddies 2004 STOCK LS1 Vette and he put down 525 RWHP and 490 RWTQ and it was completely stock MN6 with full Kooks exhaust system and Meth.
Do not use the stock MAF but go to the 2 BAR MAP sensor set-up and you'll get the desired results - It will need to be re-tuned but it'll be worth it.
Let me know when the graph is up too!
Thanks,Matt
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
In my beginning with only catback & cats deleted, CAI, Hypertech "canned" tune I made 337rwhp on my 99 MN6. With AFR 205's, Kooks LT's and the baby blower cam in my sig power moved up to 397rwhp. Then a couple months later the LS6 intake & A&A Vortech S-Trim system with 7-8psi was installed and the power jumped to 606rwhp 
FWIW for everyone that may not know, the camshaft specs on a 98 are .479/.472-207*/198*-117lsa.
Good Luck with Your Car
FWIW for everyone that may not know, the camshaft specs on a 98 are .479/.472-207*/198*-117lsa.
Good Luck with Your Car
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Plus the 98's operating system is limited, so a 2 BAR MAP sensor would do well in his case as it did for me, being I also have a '98.
It takes it past the stock MAF table so there is "NO" guessing at what the VE tables etc should be at, as opposed to using the 2 BAR MAP
and being able to tune for the best HP and TQ under BOOST.
Thanks,Matt
Melting Slicks
Joined: Sep 2005
Posts: 2,521
Likes: 146
From: Watertown CT
The 98's MAF's suck in comparison to the later model MAF's on the Vette's!
Plus the 98's operating system is limited, so a 2 BAR MAP sensor would do well in his case as it did for me, being I also have a '98.
It takes it past the stock MAF table so there is "NO" guessing at what the VE tables etc should be at, as opposed to using the 2 BAR MAP
and being able to tune for the best HP and TQ under BOOST.
Thanks,Matt
Plus the 98's operating system is limited, so a 2 BAR MAP sensor would do well in his case as it did for me, being I also have a '98.
It takes it past the stock MAF table so there is "NO" guessing at what the VE tables etc should be at, as opposed to using the 2 BAR MAP
and being able to tune for the best HP and TQ under BOOST.
Thanks,Matt
Dan