Quest for Speed
 

I've hit a brick wall in my quest for speed. I have a 27 world class and can not get more than 72 out of it. With a bone stock 330 hp 7.4 the boat ran a solid 54 w/22p prop. I put 568 hp & 621 ft-lb in and ran 68 @ 4900 RPM w/ 24p but would porpoise really bad. I then put a 26p on, improved ride, kept the same RPM and lost 2 mph.
I wanted more speed and built a new motor w/ 682hp & 742 tq and picked up 2 mph. It will now spin a 26p & 28p around the same speed of 70mph and 5k rpm. Both motors were on the dyno so I know we are talking accurate numbers.
I've tried standard bravo XR and then put a IMCO lower standard length and lost speed. I've tried carb and efi. Ive used multiple ignition systems and it will not spin over 5k rpm. Ive tried 24, 26 & 28p bravo one 4 blade props. Trim does not really effect speed unless trimming to the moon squeezing every last mph out of it. The numbers do not add up and any advice would be appreciated.

What is your prop shaft depth? have you tried moving weight around? What RPMs on the Dyno and where was it making power

Prop Shaft depth is 6 1/4 going to weigh the boat

Air, fuel, and spark.

You dealt with spark, now you have to deal with air and fuel. Air and fuel is not only what's bolted to, or in, the engine.

edit in: don't be afraid to unplug your tach for a few test runs in case this is limiting your rpm. Yes, it happens !

Have you checked the hull bottom? It seems that Warlocks are all over the place for speed. The fact that you only ran 56mph with 330hp and now have a porpoise at higher speeds, points to a hull issue like a hook.

And the bottom could been effected by how it was stored thru out its life. Racked stored or trailer bunks or even how a forklift picked it up to sit it in tje watwr or on a trailer.

And the bottom could been affected by how it was stored thru out its life. Racked stored or trailer bunks or even how a forklift picked it up to sit it in the water or on a trailer. Any of this could cause problem areas in the bottom hull

The 27 have major hooks in them.. I used to race one...Best we could do was 82 mph with a 509 ci 525hp ..