ls1 heads

Reply Subscribe

Thread Tools

Search this Thread

Jan 5, 2009 | 03:26 PM

iroc1793

Thread Starter

Staging Lane

iTrader: (3)

Joined: Oct 2007

Posts: 85

Likes: 0

From: Turners Falls, Ma/Houston, Tx

ls1 heads

What is the differnce other than the valve cover bolt pattern for the ls1 heads between 97-98 and 99 and up, i have been told that 99 and up heads flow better? why is that if its true

Jan 5, 2009 | 06:31 PM

00silver6

12 Second Club

iTrader: (4)

Joined: Nov 2005

Posts: 387

Likes: 0

nothing! unless that person is talking about flow in general due to 01 and 02 have the ls6 intake. but if just the heads then no.

Jan 5, 2009 | 07:08 PM

blackLS1m6

TECH Apprentice

iTrader: (14)

Joined: Jul 2008

Posts: 301

Likes: 1

From: Villa Park, Illinois

I always heard that the 97-98's didnt flow as well as later heads?

Jan 5, 2009 | 08:26 PM

Shawn MacAnanny

TECH Addict

iTrader: (12)

Joined: Jul 2004

Posts: 2,105

Likes: 3

From: Delaware

241s were media casted as opposed to sand casted which results in a smoother intake runner. that is all.

Last edited by Shawn MacAnanny; Jan 5, 2009 at 08:34 PM.

Jan 5, 2009 | 08:27 PM

00silver6

12 Second Club

iTrader: (4)

Joined: Nov 2005

Posts: 387

Likes: 0

1997-1998 ls1 pn# 12559853 comb chamber vol. 66.67 in/ex 200/70 cc

99-03 12564241 66.67 in/ex 200/70 cc

Jan 5, 2009 | 10:23 PM

iroc1793

Thread Starter

Staging Lane

iTrader: (3)

Joined: Oct 2007

Posts: 85

Likes: 0

From: Turners Falls, Ma/Houston, Tx

so if im understanding this correctly, the 99 and up heads were just casted differently resulting in better flowing heads.

Jan 5, 2009 | 10:39 PM

SS1875

11 Second Club

iTrader: (34)

Joined: Feb 2005

Posts: 3,158

Likes: 0

From: Ft. Wayne, Indiana

In random testing the sand casted heads have been about 5 to 7hp down from the SPM (semi-permanent molded) heads. That really is the only difference in the LS1 heads.

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Brett Foote

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

Pouria Savadkouei

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Verdad Gallardo

7 Most Reliable High-Performance Engines GM Has Ever Built

Verdad Gallardo

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Verdad Gallardo

6 Common C5 Corvette Failures and What's Involved In Repairing Them

Pouria Savadkouei

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

Verdad Gallardo

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Pouria Savadkouei

Top 10 Most Powerful Chevy Trucks Ever Made!

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Verdad Gallardo

Jan 6, 2009 | 01:20 PM

w3s1c0a5t

TECH Enthusiast

iTrader: (3)

Joined: Nov 2008

Posts: 726

Likes: 0

What about after porting? any difference?

Jan 6, 2009 | 02:49 PM

#10

Shawn MacAnanny

TECH Addict

iTrader: (12)

Joined: Jul 2004

Posts: 2,105

Likes: 3

From: Delaware

I'm positive the heads up until 241s (late 2000) were all sand casted. Since 243 heads werent cast until them i am sure they used the same media (i forogt exactly what it is) would be used for the 243s also.

Reply Subscribe

ls1 heads

ls1 heads

Trending Topics

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

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

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

7 Most Reliable High-Performance Engines GM Has Ever Built

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

6 Common C5 Corvette Failures and What's Involved In Repairing Them

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

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Top 10 Most Powerful Chevy Trucks Ever Made!

Hennessey's New Supercharged Silverado ZR2 Has 700 HP