Will I gain anything with this exhaust swap?
#1
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Will I gain anything with this exhaust swap?
Here is what I'm looking at doing. I have my 502 out for a rebuild Gen 5 with a carb.. It's going 40 over. we are raising the compression to about 9.3. Also doing a retro roller cam coversion. I think I will be about 500HP when done,maybe more. Boat is a 272 Baja.
Right now I still have the stock steel center rise exhaust going straight out the transum. Since I'm on a tight budget , I was looking at picking up a set of the alum. mercruiser/gil exhaust for a good price, $600.00. My question , is this exhaust swap worth it? Thanks
Right now I still have the stock steel center rise exhaust going straight out the transum. Since I'm on a tight budget , I was looking at picking up a set of the alum. mercruiser/gil exhaust for a good price, $600.00. My question , is this exhaust swap worth it? Thanks
Last edited by crf311; 06-04-2012 at 09:51 PM.
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Exhaust is one of the best upgrades that you can make when upgrading from factory exhaust! I picked up a set of stainless marine manifolds and risers last year for $800.00
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if it is still a merc style exhaust that a stock merc riser will fit on, very little increase in flow. it still has a 2.1 by 2.5 inch hole on top all of the exhaust has to squeeze through. PLUS it has the shortest distance you can get between exhaust valves and the point where water mixes with exhaust gasses. (not counting same manifold with 3 inch risers.) one hp per inch motors generally have enough valve overlap to suck water at idle with longer riser length than these. the only place you will notice perf increase is taking 100 lbs out of back of boat. look in swap shop for a used set that will do what you need them to do.