bertram31.com

after some how posting this in Buy and sell, I deleted it all and moved it here.....



So after my guy fell of a boat and shattered his heal, the new pretty engines have been sitting in the boxes for the last 3 or 4 months. I chose marine powers semi tuned exhaust for it as well to help with flow and being as they are about an hours drive from me. I called on black Friday and asked if they had any specials and was laughed at.... They said just take the ride and will make it worth the ride. So 4 risers, 4 manifolds all the bolts and hard ware......$700 bucks!!!!! Made my months, not just my day.

so here they are on the dyno and the sheets.....







I bit down on the HP I was expecting, but I will gladly take that torque if I lose a bit of HP. Currently running a 650cfm quickfuel, and you can see the major drop off at about 4850 rpms... so could really pick up some HP and lose some torque with a 750. but I like this graph. This is also with out multi spark hooked up.......

so much for the deal on the exhaust! Both of them on the port engine are now leaking. Luckily they are not in the boat yet. I have called marine power already and they said no issues. They will just swap them out. Hopefully I am doing some sea trails in the next 3 weeks to get all the baselines for new wheels.

Leaking water at the elbow's spacers?

no, those are just there for tuning so we can place 02 sensors to get fuel trims perfect. Its leaking at the head where the manifolds bolt up. We changed the gasket but it still does it, so it must have a crack in it.

Nice dyno. 300hp & 400+ ft lbs TQ, where you can actually use it, at 3000 rpm. Should do nicely.

I hope so. sorry for the time between responses, but mcafee kept shutting me out of the site. Did run into a one last problem. The new exhaust doesn't clear the engine bay doors. Guess I'm off the fiber glass man to get the front floor lifted 3 inches. Unless someone has any other ideas?

Going into a 28 correct?

Can you lower the engine beds so the engine sits closer to the floor? It would force a change in the shaft angle so you would need to have new struts made. Plus side if you do it correctly, the prop clearance to the hull does not change. The Boat becomes more efficient due to change in shaft angle.

it would have to be about 3 to 4 inches. The issues comes from going from old rear log style exhaust to new center riser. I didn't do the math on this. I was so worried about carb and intake height I didn't even measure this. The covers are already "notched" to clear a 1in spark arrestor, so I had about zero room to spare. I did gain about 2in of clearance there getting rid of the Rochester's and using quick fuels with a HP intake.