You can enlarge the exhaust ports a bit but not so much to match the gasket bore. The reason is to prevent exhaust gas reversion from the header back into the combustion chambers. Otherwise the fresh intake charge would be diluted with spent exhaust gases and the result would be a power loss.kkchevy3 wrote:and why should the exhaust not be enlarged?
4.2 vs 4.6 as a DD?
-
Cheromaniac
- I live here
- Posts: 3290
- Joined: March 8th, 2008, 12:58 pm
- Stroker Displacement: 4563cc
- Vehicle Year: 1992
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
- Location: Cyprus
Re: 4.2 vs 4.6 as a DD?
1992 XJ 4.6 I6 Stroker - 5MT - 200rwhp 258rwtq - Sold 
-
sly-jeeper
- Donator
- Posts: 150
- Joined: December 29th, 2013, 9:17 am
- Stroker Displacement: 4.6L
- Vehicle Year: 1994
- Vehicle Make: jeep
- Vehicle Model: cherokee
- Location: Kaleva, mi
Re: 4.2 vs 4.6 as a DD?
yep just like a two stroke!