If you plug the top water intake hole how much psi could you gain? If you jack it up to were you you have 16lb, and you plug the top hole would it give you 2 or 4lb more psi? I have seen some motors setup like that. Can it help very much? Is this a good thing to do?
I don't believe anything short of a Bob's nosecone low water pickup addition would be worth the risk. Personally I don't know of anyone trying stopping up any of the 4 little holes on an OMC/Bombardier product. I have heard of it being done to Mercs. Honestly unless you have a very light boat (Allison Bullet Stroker Norris craft or similar) unless you can afford MOD the He!! out of it, keep it like it is and just have a good reliable fishing motor. Until lately the LU just aren't designed to surface props without grenading, same with the engines unless they are heavily modded, RPM's in the 6000 range constantly is going to guarantee you a bucket of bolts pretty quick.JMHO
I was told you can plug the top one. What you want to watch is loosing pressure in turns. I could raise my engine on my old boat and keep decent water pressure, but go into a turn, and it would drop to 0.
In my opinion, you aren't going to gain enough in MPH adding a nose cone and LWP's so you can raise the engine to over come the drag, unless you have an Allison, Stroker, or Bullet, or some sort of tunnel hull.
Also, if you surface an OMC lower, you have to pin the bearing carrier or you will have issues in fairly short order. It's a common mod, but it won't last long without it in a surfacing situation.
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96 Javelin 379SE 96 Johnson 150 (J150ELEDB)
Mods: FS carbs, Ficht reed cages, boyesen reeds and
Baker Hot Heads.
He had the regular OMC one, with the 4 inlet holes on each side, like what would come on a X-flow.
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96 Javelin 379SE 96 Johnson 150 (J150ELEDB)
Mods: FS carbs, Ficht reed cages, boyesen reeds and
Baker Hot Heads.
You could plug the upper hole. This allows you to raise your engine for less drag and MAYBE get a little more speed and handling advantage, however, there are numerous variables that are also involved in this modification that make it impossible to answer your question completely. The water pressure situation may or may not change. One thing to be very careful of when doing this, Make sure you don't allow your sealant material to enter the path of cooling water from the 3 holes left to do the work. You may also want to consider a little grinding on the leading edges of the intake holes for better water entry.
We've done that with that type gearcase and it's worked OK. Didn't really see an increase in pressure but it did stop air from getting in. As mentioned, be careful to not get anything in the water's path. We threaded the holes and screwed in little aluminum plugs.
On most of those cases there's actually enough room to plug the top 2 on each side and create another hole below the lowest existing hole. The old factory scoops worked pretty good too.
I dont know witch one it is. It has 4 holes stacked on top of each other. It dosnt looke like my friends 2000 gt.
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