Click here to visit LS1Tech
Click here to visit Performance Trucks
Click here to visit Mod Motor Tech
Click here to visit Modern Hemi
LS1Tech Wiki

LS1TECH  

Go Back   LS1TECH > LS1-LS2-LS3-LS6-LS7 PERFORMANCE > Generation IV External Engine
New! Use your Facebook, Google, AIM & Yahoo accounts to securely log into LS1Tech.com, click logo to login  

Reply
 
Thread Tools
Old 11-01-2009, 02:29 AM   #1
TECH Regular
 
Coonass350's Avatar
 
Trader Rating: 1
Join Date: Aug 2006
Location: Louisiana
Posts: 457
Default No Cats vs Hi Flow Cats??

hey guys i was wondering what the difference would be on an 05-09 Corvette C6 with either the LS2 or LS3, am making a list of mods that i plan on getting once i get the car and am not dead set on getting a certain year/model yet. i actually have 2 questions:

1. which are better; American Racing, Kooks, or LG Motorsports longtubes?

2. what is the hp/tq difference when running no cats vs running hi flow cats? i want the most hp/tq i can get but am scared with no cats it will be loud and poppy sounding like glass packs. i hate that sound.

sorry if some think this is a stupid question but im new to Vettes and am just getting opinions & ideas. thanks in advance.
__________________
'94 Chevy Silverado 5.7 357 ci
Comp Cams 206/212 .434/.444 112*,Custom Chip from TBI Chips,Jet TB spacer,Flowmaster 40 series w/no cat
Coonass350 is offline   Reply With Quote
Old 11-01-2009, 07:38 AM   #2
12 Second Club
 
Trader Rating: 0
Join Date: Jun 2004
Posts: 972
Default

Ive run this test, hi flow cat vs test pipe, on an engine dyno before with a full Dynatech headers back setup and there was a 3-4hp difference on a 535hp LS1.

Run the cats, itll save you possible fines, it wont pop, and you wont feel the difference of 3-4hp, which is only 2rwhp or so.
__________________
Quote:
Originally Posted by John Lingenfelter
The world's best cam combined with a poor set of heads will produce an engine that's a dog. But bolt on a set of great heads even with a poor cam, and that engine will still make great power.
SweetS10V8 is offline   Reply With Quote
Old 11-01-2009, 09:37 AM   #3
TECH Regular
 
Coonass350's Avatar
 
Trader Rating: 1
Join Date: Aug 2006
Location: Louisiana
Posts: 457
Default

Quote:
Originally Posted by SweetS10V8 View Post
Ive run this test, hi flow cat vs test pipe, on an engine dyno before with a full Dynatech headers back setup and there was a 3-4hp difference on a 535hp LS1.

Run the cats, itll save you possible fines, it wont pop, and you wont feel the difference of 3-4hp, which is only 2rwhp or so.
alright man thanks for the help. and do you know if it will pop without the cats?

also what headers to go with? American Racing, Kooks, or LG Motorsports?
__________________
'94 Chevy Silverado 5.7 357 ci
Comp Cams 206/212 .434/.444 112*,Custom Chip from TBI Chips,Jet TB spacer,Flowmaster 40 series w/no cat
Coonass350 is offline   Reply With Quote
Old 11-01-2009, 04:06 PM   #4
12 Second Club
 
Trader Rating: 0
Join Date: Jun 2004
Posts: 972
Default

The Dynatech setup, headers/cats/cat back, was really a nice piece. I dont have experience with the others.
__________________
Quote:
Originally Posted by John Lingenfelter
The world's best cam combined with a poor set of heads will produce an engine that's a dog. But bolt on a set of great heads even with a poor cam, and that engine will still make great power.
SweetS10V8 is offline   Reply With Quote
Old 11-01-2009, 10:26 PM   #5
TECH Regular
 
Coonass350's Avatar
 
Trader Rating: 1
Join Date: Aug 2006
Location: Louisiana
Posts: 457
Default

Quote:
Originally Posted by SweetS10V8 View Post
The Dynatech setup, headers/cats/cat back, was really a nice piece. I dont have experience with the others.
oh okay.
__________________
'94 Chevy Silverado 5.7 357 ci
Comp Cams 206/212 .434/.444 112*,Custom Chip from TBI Chips,Jet TB spacer,Flowmaster 40 series w/no cat
Coonass350 is offline   Reply With Quote
Old 11-01-2009, 11:50 PM   #6
TECH Junkie
 
Trader Rating: 0
Join Date: May 2008
Location: South Florida
Posts: 3,282
Default

Quote:
Originally Posted by Coonass350 View Post
hey guys i was wondering what the difference would be on an 05-09 Corvette C6 with either the LS2 or LS3, am making a list of mods that i plan on getting once i get the car and am not dead set on getting a certain year/model yet. i actually have 2 questions:

1. which are better; American Racing, Kooks, or LG Motorsports longtubes?

2. what is the hp/tq difference when running no cats vs running hi flow cats? i want the most hp/tq i can get but am scared with no cats it will be loud and poppy sounding like glass packs. i hate that sound.

sorry if some think this is a stupid question but im new to Vettes and am just getting opinions & ideas. thanks in advance.
My 427ci in my sig started out with Random Tech high-flow cats. Like a dummy I had a shop gut them. Absolutely zero performance change, but I did get a little louder and through 2nd gear a little into 3rd gear with a medium acceleration I have that choppy, poppy exhaust sound. Under hard acceleration it sounds smooth and normal through all gears. If you want it to sound smooth and definitely be a little more quiet....use the cats.

.
__________________
1998 WS6 T/A 492 RWHP//495 RWTQ (w/cats)
LS6 427ci LPE short block, Ported stock TB, Ported LS6 intake, Ported LS1 heads, cam: 244/244 .610/.610 114 lsa, 1 7/8" Grotyohan LT's, 3" custom "Y" back to a Magnaflow Muffler, Built tranny...by a friend, Strange 12 bolt, 3.73 gears, Baer brakes, Hotchkis STB, LG Motorsports: Panhard Rod, LCA's, SFC's, G2 Super Springs, Hals all around, 315/rear, 275/front

Life may not be the party we hoped for, but while we're here we might as well DANCE.
LS6427 is offline   Reply With Quote
Old 11-02-2009, 01:21 AM   #7
TECH Regular
 
Coonass350's Avatar
 
Trader Rating: 1
Join Date: Aug 2006
Location: Louisiana
Posts: 457
Default

haha alright, thanks for the advice man i appreciate it.
__________________
'94 Chevy Silverado 5.7 357 ci
Comp Cams 206/212 .434/.444 112*,Custom Chip from TBI Chips,Jet TB spacer,Flowmaster 40 series w/no cat
Coonass350 is offline   Reply With Quote
Reply

Tags
car, cat, cats, custom, dyno, engine, exhaust, flow, flowmasters, hiflow, high, louder, make, power, running


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off



All times are GMT -5. The time now is 06:11 PM.

LS1TECH - Archive - Top

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.2.0
Advertising - Terms of Service - Privacy Policy - JOBS