CRG Discussion Forum

Camaro Research Group Discussion => Mild Modifications => Topic started by: crossboss on November 07, 2019, 04:47:51 PM

Title: Mark IV Big Block exhaust manifolds
Post by: crossboss on November 07, 2019, 04:47:51 PM
Boys,
Need a bit of advice/help on this one. What Mark IV Big Block cast iron exhaust manifolds flow the best with square port heads. I am not chassis restricted, so no worries there.
Title: Re: Mark IV Big Block exhaust manifolds
Post by: firstgenaddict on March 31, 2020, 11:56:50 PM
The corvette style are the better cast iron "manifolds".
 The 4 branches come together more like the old SD pontiac "header" exhaust manifolds on the 421's.
Title: Re: Mark IV Big Block exhaust manifolds
Post by: crossboss on April 09, 2020, 06:33:34 PM
Quote from: firstgenaddict on March 31, 2020, 11:56:50 PM
The corvette style are the better cast iron "manifolds".
 The 4 branches come together more like the old SD pontiac "header" exhaust manifolds on the 421's.




Thanks, much appreciated!
Title: Re: Mark IV Big Block exhaust manifolds
Post by: firstgenaddict on April 20, 2020, 03:25:59 PM
You could "EXTRUDE HONE" them as well...
Title: Re: Mark IV Big Block exhaust manifolds
Post by: crossboss on April 20, 2020, 10:45:41 PM
Quote from: firstgenaddict on April 20, 2020, 03:25:59 PM
You could "EXTRUDE HONE" them as well...



Yes, that was also in the plan to do list.