Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Less power???

Thread Tools
 
Search this Thread
 
Old May 23, 2012 | 07:07 AM
  #1  
Blackhawk8's Avatar
Thread Starter
Teching In
 
Joined: Nov 2011
Posts: 37
Likes: 0
From: Paradise Newfoundland Canada
Default Less power???

I just completed a 1 7/8 Kooks header install on my 2000 Firehawk. The car is completely stock other the a slp lid. I had the car tuned (street tuned so no hp numbers) but now the car feels like it has less power then when it was stock. I have not dynoed the car, but when the car was stock if I jumped on it from 3000rpm up it would start to break the tires loose, now if I pull out and jump on it, it doesn't spin the tires at all and doesn't feel like it pulls the same. Any ideas on what could be the problem?

The headers and catted y-pipe where bought used from a member on here, with about 2000 miles on them.
Reply
Old May 23, 2012 | 10:02 AM
  #2  
s346k's Avatar
TECH Junkie
iTrader: (4)
 
Joined: May 2005
Posts: 3,433
Likes: 1
From: johnson co.
Default

sounds odd.

i put 1 7/8 hooker super comps on my ta (lid, headers, weld in muffler only). stock tune before the car would spin out of first and a little on 1-2 then stop. now it will spin 1st, and basically all of 2nd. the car will actually spin from a 50 roll in 2nd gear now. it pulls noticeably harder everywhere above 2k rpm.
Reply
Old May 23, 2012 | 10:06 AM
  #3  
redtan's Avatar
TECH Junkie
iTrader: (5)
 
Joined: May 2008
Posts: 3,764
Likes: 17
From: Belmont, MA
Default

Either the tune is whack or you're underestimating your butt dyno.

Take it to a track or dyno and see what numbers it puts down. Then we can say if it's the tune or just you.
Reply
Old May 23, 2012 | 10:19 AM
  #4  
thunderstruck507's Avatar
11 Second Club
iTrader: (18)
 
Joined: Mar 2008
Posts: 8,358
Likes: 27
From: Northwest AR
Default

Was it tuned with a wideband?
Reply
Old May 23, 2012 | 11:12 AM
  #5  
Blackhawk8's Avatar
Thread Starter
Teching In
 
Joined: Nov 2011
Posts: 37
Likes: 0
From: Paradise Newfoundland Canada
Default

Yeah it was tuned with wideband. Is there a chance the cats could be clogged?
Reply
Old May 23, 2012 | 11:13 AM
  #6  
Blackhawk8's Avatar
Thread Starter
Teching In
 
Joined: Nov 2011
Posts: 37
Likes: 0
From: Paradise Newfoundland Canada
Default

And I'll be bringing it to a dyno tomorrow hopefully.
Reply
Old May 28, 2012 | 06:51 AM
  #7  
Blackhawk8's Avatar
Thread Starter
Teching In
 
Joined: Nov 2011
Posts: 37
Likes: 0
From: Paradise Newfoundland Canada
Default

Hey s346K what gears are you using?
Reply
Old May 28, 2012 | 01:27 PM
  #8  
I8UR4RD's Avatar
TECH Addict
iTrader: (16)
 
Joined: Oct 2010
Posts: 2,593
Likes: 2
From: Bama
Default

what are cats? ;D lol ......with those headers you may lose some low end tq due to the backpressure etc etc.....but power should still come up. take it to be tuned and find out.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-1

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-2

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-3

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-4

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-5

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-6

10 Camaros You Should Never Buy

 
story-7

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
story-8

Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

 Brett Foote
story-9

10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

 Verdad Gallardo
Old May 28, 2012 | 05:30 PM
  #9  
s346k's Avatar
TECH Junkie
iTrader: (4)
 
Joined: May 2005
Posts: 3,433
Likes: 1
From: johnson co.
Default

the only low end tq loss i noticed was 1-2k rpm. everywhere else the car is more powerful. untuned of course. i'm sure tuning on it would make it even more obvious.
Reply
Old May 29, 2012 | 02:36 AM
  #10  
69cutlassrkt's Avatar
On The Tree
 
Joined: Aug 2008
Posts: 129
Likes: 1
From: Texas
Default

Originally Posted by I8UR4RD
what are cats? ;D lol ......with those headers you may lose some low end tq due to the backpressure etc etc.....but power should still come up. take it to be tuned and find out.
the whole backpressure thing is a myth.
Reply
Old Jun 6, 2012 | 01:10 PM
  #11  
Blackhawk8's Avatar
Thread Starter
Teching In
 
Joined: Nov 2011
Posts: 37
Likes: 0
From: Paradise Newfoundland Canada
Default

Just had the car on the dyno, 269hp and 276FT/lbs so I guess there's something wrong. My air/fuel went from 14.7 at 2500rpm to 15.5 at 5600rpm. The dyno shop here does not have a tuner so he could not make any changes for me. I'm currently trying to get a hold of the tuner to see what is going on.
Reply
Old Jun 6, 2012 | 01:16 PM
  #12  
redtan's Avatar
TECH Junkie
iTrader: (5)
 
Joined: May 2008
Posts: 3,764
Likes: 17
From: Belmont, MA
Default

That's an awful tune or you have fuel delivery issues. DO NOT, I repeat DO NOT get on your car full throttle again until you fix your fueling issues.

You will quickly melt a piston(s) at that AFR going full throttle.
Reply
Old Jun 6, 2012 | 01:23 PM
  #13  
Blackhawk8's Avatar
Thread Starter
Teching In
 
Joined: Nov 2011
Posts: 37
Likes: 0
From: Paradise Newfoundland Canada
Default

Yeah tell me about it. I've been using the car for about 2 weeks now and have had it WOT many times, I hope i haven't caused any damage.
Reply
Old Jun 6, 2012 | 07:56 PM
  #14  
AmarilloWS6's Avatar
TECH Enthusiast
iTrader: (3)
 
Joined: Aug 2011
Posts: 520
Likes: 0
From: Van Buren AR
Default

Originally Posted by redtan
That's an awful tune or you have fuel delivery issues. DO NOT, I repeat DO NOT get on your car full throttle again until you fix your fueling issues.

You will quickly melt a piston(s) at that AFR going full throttle.
My car had the exact same issue! I have everything in my sig and my car only made 270 rwhp off the bat on TSP's dyno, he said I had a fuel delivery problem. We eventually got it tuned up to 340 rwhp but he said it wasn't exactly tuned right either so idk? It's been running fine for about 4 months now. I just don't know where to start in finding the problem. My fuel pressure's where it should be and I have a new fuel filter and all injectors are new. Haven't checked the fuel pump but it seems fine?
Reply
Old Jun 6, 2012 | 09:39 PM
  #15  
stunna p's Avatar
Launching!
iTrader: (4)
 
Joined: Nov 2009
Posts: 214
Likes: 0
From: charlotte
Default

id take off the y pipe and drive it open header to see if made a difference. at least you can rule out the cats....
Reply
Old Jun 6, 2012 | 10:46 PM
  #16  
s346k's Avatar
TECH Junkie
iTrader: (4)
 
Joined: May 2005
Posts: 3,433
Likes: 1
From: johnson co.
Default

factory 342s..
Reply




All times are GMT -5. The time now is 05:10 AM.

story-0
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-1
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-2
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-3
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-4
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-5
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-6
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-7
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE