The wait is absolutely killing me! Started my ZT 280 Checkmate project a year ago this past fall and dropped her off at one of the best, Performance Marine/Saris racing. I bought her with the intent of doing this, and while looking for a "hull" my only requirements were it had to be 25 to 28 feet, have a 502, and have hydraulic steering. fast forward to today and she has a Saris 3.8L Whippled 509 that made 957hp @ 6000 rpms on pump gas. This engine build was even featured in PRI's Engine Builder magazine. The only thing we retained was the block and crank. On the back end we put some 280 K-planes on and a new 1.36 ratio IMCO dual downshaft SCX with a -2 lower and a 1" spacer to start. To say that Jason and Johnny Saris and crew have been a pleasure to deal with is the understatement of the year. These guys have gone above and beyond in keeping me informed, calling whenever they'd run into something that was an issue or could be an issue, and last but not least the enthusiasm for this crazy project to begin with. She's 99% done and just waiting for spring to arrive in Lake George, NY, the home of Saris Racing, so some minor gelcoat work where the old tabs were can be completed, and so Johnny can tune this beast in the boat and play with propellers. She should be a wild ride and I'm sure it will remind me a little of one of the three Hydrostreams I've owned, just on a bigger scale. So hurry up calendar and Mother Nature, it's time to giddy up!

Jason and Johnny did all of the re-rigging with a new 250R on my 22 Progression. My experience was exactly like yours. Why can't more marine dealers be like them? Absolutely top notch!

That engine thou ...

Kellucca,

Did we keep it under the sundeck?

Thanks. Brad.
(937)545-8991

We sure did! Sleeper....... tall windshield and all.

Kellucca,

That's awesome. I've got fantasies about something similar with my PQ280. I've been leaning more towards NA big cubes to get there, but it's good to know an intercooled Whipple with likely squeeze in there. As much of an uphill battle the expenditure will be with the War Department, it would be an absolute non-starter if it won't fit under her sundeck.

Very interested in the numbers you find.

Thanks. Brad.
(937)545-8991

Very proud of that engine. It was the first one we really turned the 3.8 loose on. Thanks for the kind words Mike, you've been a pleasure to work for!

I went nuts a few years ago and built three from the ground up 675 hp 548's N/A and never again. They pushed my '91 straight bottom Fountain to just shy of 100 mph but were just a giant maintenance nightmare.These new 3.8L direct port injected Whipples make big power and you don't need radical cams that are torture on valvetrain. This thing isn't even breathing hard on the dyno at 975 hp. A tad smaller pulley and this thing makes 1100 all day with a splash or three of VP-C12.

Kellucca,

I'm not married to any one approach. I just figured that, since the GM 632 crate motor is advertised at 1004HP, a comparably built 565 would get pretty close to my dreamed goal of 850. I am about as far from an expert on the topic, though.

But, I'm also a HUGE fan of the sound of a blower motor, so........

Thanks. Brad.
(937)545-8991

wow.....that checkmate is a major sleeper. Your going to surprise alot of hot boaters out there. As a Lake George powerboater, ur secret is safe with me. Saris guys are great. We're lucky to have them on the lake to keep some level of high performance boating alive.