Can I run stock Y-pipes on a 500HP motor?
#11
Registered
Thread Starter
Thanks for post guy's. I have seen that higher riser manifold, but is that the right choice for silent choice HP500's? There are two manifolds with silent choice, one by stainless marine and another by Gill, I presume the mercruiser 500hp exhaust was the gill exhaust under a OEM label. When I look online like here gil-header.jpg (1920×1229) (cpperformance.com) I can see the higher rise manifold, but the magnum choice appears to be setup for silent choice and nothing mentioned on the HP500 riser manifold about silent choice. Stainless marine manifold with silent choice does not appear to have the higher riser either as a choice for silent choice exhaust.
#12
Registered
Thread Starter
#13
Registered
I should add my risers have been modified to accept the diverts they are not as long as(as in one pieces) the pic above towards the transom. I assume Donzi did that at the factory I will try to take some Pics tonight from a better angle.
#14
Registered
I had Eddie Marine mans and elbows on my stock 502 MPI using short risers and Corsa modified diverters to the Y pipe. After repower 530HP they were placed on the shelf and got +3 risers and turn downs. Its quite around the dock
#15
Registered
This is how the diverters were done you can see where they cut and shortened. When I had it apart there is small dam welded on the bottom. Honestly you could just use the tails and get the large muffler tips, it really takes the bark out of it. You can have a conversation at cruise speed.
The following users liked this post:
SB (06-15-2022)
#16
Gold Member
Gold Member
Just my opinion, but I hated my switchable mufflers. Constantly leaking around the seals, pulling the tails every year to replace the seals. Greatest day of my life was getting rid of them.
again, just my .02.
again, just my .02.
#18
Registered
I bought a 1989 28 saber less power. It came with bravo drives and transom assemblies plus a few extra parts, including like new Y-pipes for a stock 454 365hp mercruiser motor that was originally installed when new. My question is can I run the stock Y-pipes on the new power, a mercury racing 500HP motor rebuilt to a 509ci? I would love to be able to run the Y-pipes around the docks and maybe pulling kids on the tube. I am going to have to buy exhaust manifolds, probably the stainless marine manifolds that are compatible with switchable exhaust. My main concern is reversion or anything else that could create motor problems.
The following users liked this post:
getrdunn (06-15-2022)
#19
Registered
Thread Starter