Having my 420's rebuilt and need to change exhaust. Bore and stroke to 496, new roller cams. Hope to be around 500HP when they're done. My old exhaust was a proven engine destroyer, the old Merc w/SS tails...Before they went to the Merc/Gil system. Any suggestions on replacements ? Boat is a 1988 357. Thanks...

When i had to ditch my original merc stuff (same as yours) because they were leaking so bad i went with imco powerflows. It was june in illinois and i was ready to be back on the water, teague had them in stock with the longer tails for trs application. You have alot of options but I am still happy with my purchase, they sound really nice.

want looks or affordable?

I went affordable and used stock 496 stuff on mine, 500.00 for take offs on each engine, nice stainless risers, you can have the black taken off and polish them, I left mine black for now..

Full Force...Did you have to recut your transom holes? My trs risers go a lot higher up than bravo set ups. I looked into revolution marine when i was doing mine but they said i would have to recut my outlets in the transom or they wouldn't be able to get the water out.

I was trying to find 2 used sets, but the TRS risers are hard to find. I also want the long 6" taller risers. Thanks for your info and pics, always helps to see how they look in the boat.
Anyone else have any pics to share ? Thanks again....

No holes are same location, I am TRS also, I used my same holes but made them 4" they were 3" before, I have no issues whatsoever..

full force it looks like your exhaust hoses are touching, there is almost no room between your engines! I can fit my arm between my two inboard manifolds. Nice looking motors by the way

Thanks!

Yea, my engines are tight certerline, usually they are wider...

Coldsweat,
I basically did what you are doing, I went with the CMI's. here is my add on another site, to see the application.

https://www.boatcrazy.com/search/details.php?id=468

see what you think, the original owner re-drilled the thru-transom higher as you can see its above the taco rail in the back. Good Luck !

do you have a pictures of your current exhaust? I just want to see if your ''engine destroyer'' exhaust looks loke mine????

Also thinking switching for newer exhaust, for the affordable way...