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powerplay230
06-12-2001, 08:33 PM
Hello hoping someone has had experience with something similar and can help me out. I am in the process of repowering my boat from a base 7.4/Bravo to a 450hs/8.2 with the bravo. Hull is a 1989 23' Powerplay that has been just great. I am trying to get the most performance and reliability out of the new set up. Anyone have any experience with the performance/life expectancy of the Stainless marine or Gil aluminum manifolds with stainless risers as compared to the factory Mercruiser manifold/risers. Exhaust it routed directly thru transom. Boat only ran 55 with the old 330hs 7.4 so I am looking for anything that will help provide a substantial improvement without shortening the life of my new engine. Any other tips would be appreciated also. Thanks Rich

dirtlawyer
06-13-2001, 04:25 AM
Rich -
Stainless exhaust should have an equal or better life than stock exhaust - but its all in how you maintain it. Typically aftermarket exhaust will improve performace, as it will allow the engine to breath better - how much gain you'll see varies with the boat, the type of exhaust, the engine, etc.....
check out the EMI Thunder mainfolds and risers - ww.eddiemarine.com. I installed them on a 502 Mag EFI and have been extremely pleased with their performance. Also go with an aftermarket arrestor such as the Vortech, etc. Every little bit helps....
Good Luck.

LT1GMC
06-13-2001, 06:06 AM
I installed the Eddie Marine Thunder manifolds on my 502 and am very pleased with quality, fit, and performance.(plus price) http://free.***boat.net/ubb/smile.gif

No Limits !
06-13-2001, 11:41 AM
Any one of you folks have any experience or heard of anyone using IMCO aluminum or CMI SS exchaust for a 502 and what the outcome was ????????????

Dave1972
06-14-2001, 06:04 PM
Powerplay,
I have IMCO powerflow installed on my 502 Mag. EFI and have good results. I didn't gain alot of speed but the gas mileage is better and it breathes much easier. I am going to match it up with a Vortech EFI flame arrestor and possibly a reprogrammed ECU.
Hope this helps!
Dave

rookie
06-24-2001, 01:35 PM
HEY POWERPLAY, I AM REPOWERING WITH A 8.2L 450HP ALSO. I HAVE A 26' CAT DECK BOAT WITH BRAVO I. I LIVE IN SC AND AM SHOPING FOR A BOBTAIL CRATE ENGINE. WHERE DID YOU FIND YOURS? HOW WAS THE SERVICE? PRICE? TURNAROUND TIME? I HAVE SPOKEN TO A COUPLE DEALERS IN FL & NY BUT HAVEN'T BOUGHT YET. I ALSO E-MAILED YOU. ANY GUIDANCE WOULD HELP.
THANKS, ROOKIE