LT1-LT4 Modifications 1993-97 Gen II Small Block V8

HP#'s??

Thread Tools
 
Search this Thread
 
Old May 7, 2008 | 10:50 AM
  #21  
GIZMO's Avatar
TECH Addict
iTrader: (8)
 
Joined: Jan 2004
Posts: 2,780
Likes: 3
From: Shelby, NC
Default

In every test that I have made with the 561's they performed worse than the other castings. Every set of 561's that I have flowed were not as good as the earlier heads by a large margin. Maybe there are some good 561's out there. I've just never seen a set!
Reply
Old May 7, 2008 | 11:13 AM
  #22  
MadMike 97 Z28's Avatar
TECH Regular
iTrader: (3)
 
Joined: Apr 2007
Posts: 477
Likes: 1
From: Greenville, SC
Default

Originally Posted by GIZMO
In every test that I have made with the 561's they performed worse than the other castings. Every set of 561's that I have flowed were not as good as the earlier heads by a large margin. Maybe there are some good 561's out there. I've just never seen a set!
thats interesting. i wonder were the other thread got its info. is it possible the non 561's you tested were ported and 561's were unported?
Reply
Old May 7, 2008 | 11:28 AM
  #23  
GIZMO's Avatar
TECH Addict
iTrader: (8)
 
Joined: Jan 2004
Posts: 2,780
Likes: 3
From: Shelby, NC
Default

Originally Posted by MadMike 97 Z28
is it possible the non 561's you tested were ported and 561's were unported?
Absolutetly not. And were not just talking about a comparison betwean a couple of heads here. I would like to see the other guys flow sheets, because I'm not seeing what they say they have seen.

(I run Stock Eliminator which requires unported heads)
Reply
Old May 7, 2008 | 11:32 AM
  #24  
MadMike 97 Z28's Avatar
TECH Regular
iTrader: (3)
 
Joined: Apr 2007
Posts: 477
Likes: 1
From: Greenville, SC
Default

Originally Posted by GIZMO
Absolutetly not. And were not just talking about a comparison betwean a couple of heads here. I run Stock Eliminator which requires unported heads.
well thanks for the info. i learn something new everyday here.

i hope it didn't come across as i was argueing with you i just ask questions so i could learn from you guys im only 20 so i have very limited knowledge when it comes to these cars.
Reply
Old May 7, 2008 | 11:42 AM
  #25  
GIZMO's Avatar
TECH Addict
iTrader: (8)
 
Joined: Jan 2004
Posts: 2,780
Likes: 3
From: Shelby, NC
Default

I didn't take it that way at all. I had read the same thing about the 561's, fixed a set for my Stocker, and slowed it down. That is really what got me flowing the virgin castings. Maybe there are some good 561's out there. If so, I would love to hear about them.

Take Care,

Daren
Reply




All times are GMT -5. The time now is 06:24 PM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
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-6
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-7
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-8
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-9
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