Hey guys, I have a totally stock gen v 454 magnum with a quadrajet carb. I am installing some 496 exhaust manifolds and risers on it and getting rid of the stock exhaust. Does anyone know if I will have to rejet the carb.

It will be fine without changing anything on the carb.

True what Griff said but are you sure it's a Rochester Quadrajet?

Those engines came stock with Weber carbs and the 454 magnum was jetted slightly different than the 454.

You might want to check the plug color before adding the new exhaust and at several different RPM ranges after, just to make sure you don't run lean. I believe Edelbrock has a tuning kit with a chart for enrichment that would help.

Thanks guys, I planned on doing some plug checks. I am pretty sure it is a Quadrajet. I am going to go take a look at it now, you've got me wondering!

The carb on my 1995 Gen V 454 mag looked like this, yours may be different. http://www.marinecarburetor.com/Y43MercruiserOMC.htm

Just checked it is indeed a Quadrajet on a high rise aluminum intake