I want/need to replace my cast iron OSCO manifolds with Staineless or Extreme manifolds. My drives measure 33 1/2 center to center so I assuming that's center to center on my MarinePower efi 454's.

With the old OSCO cast iron's there's about 1 1/2 inches between the existing manifolds in place.

Will either Stainless or Extreme's fit? Can they be installed without pulling one of the engines?

Boat is a 1986 Formula SR357.

Thanks.

I have 33" centers. My Gils have 1/4" between them. They can be removed and installed but its actually easier to pull a motor. Forget about getting to plugs. I hope to find a silent choice compatable exhaust someday that will allow me to get at the plugs.

Poorsche,
Stainless Marine Exhaust systems will fit twin engine applications that are on 33" or greater centers, yours is a pretty typical application.

Poorsche if I remember you've got TRS's? Why don't you try the Lightning Headers. They make sets with long tails for TRS applications. They can be fitted without removing the motors in most applications. They also afford very good access to the plugs.

Call Jan direct and give him the measurements. You can buy them direct or through one of his resellers, like me, for a better price.

Fionn

I looked at the Lightning website--would need the ones with the 3" add'l ht in riser and short "tube".

One thing I liked about the Stainless is the warranty although I'm running closed cooling so the only part that gets trashed is the riser from the salt water in exhaust at that point.