1999 Longhorn Nautique Restoration Thread

THAT is an impressive difference. Very cool

That's one of the better real world examples, because you provided the dyno numbers, to see how an engine has to breathe in, combust, and breath out to live up to it's potential. What an increase with some extra fresh air!

DHMcFadin wrote: Here's my concern with the trans, it's not the horsepower I am worried about, its the torque. This engine with the gt40 intake made 488 ft lbs. That seems like a lot of torque for a PCM 40 series trans.

Eh - I have broken about a half dozen drive shafts and bent a pylon pretty good but my 40 series transmission has over 800 hrs on it without so much as a fluid change.   Those transmissions were used behind pythons from the factory and they made pretty decent torque.

Yes you might be on the edge transmission wise, in comparison torque wise 3rd gear is usually the one that goes in a T-5 manual once you get over 400hp/torque.   being your typically in lower RPM you might be ok with a larger oil cooler for awhile but looks like 80 series might be next step up.

ultrarunner wrote: Hey Dom, have you considered putting in a non-skid molded fiberglass floor with a snap-in/snap-out carpet, like modern boats? I believe someone actually did one here several years ago, and there is a thread. Eons ago I had a Bryant with the same. Loved it. Just seems the way to go with all this other work, rather than just gluing down carpet again. Ultra... ps. can I swing by and see the project? I'm flying folks down to SXSW.

Absolutely! Shoot me a text with a little heads up.

I am spraying gelcoat throughout the entire inside of the boat and then polishing the floor to install seadek. The same seadek on the trailer is being used inside the boat. Color combo is:

Beach Sand base
Terra Brown top

Go back and read the very first post. He mentions the flooring plans.

ultrarunner wrote: Ok, the following pics clearly show that crazy Texan's will paint that damn cow on anything, and that Dominic is out prowling Texas airports. This a few minutes ago in IAH. Enjoy Dom....

Don't know how I missed this! Very funny, thanks for sharing!

Hollywood wrote: Ron Tanis is the man

Agreed, he has been beyond helpful in determining what transmission I am going to need.

Couple updates:

1. Fiberglass work is moving along nicely. Once all of the deck repairs are complete and newly laid fiberglass is cured, the deck will be removed from the hull once more, then re-sprayed inside and out so that even when you lay under the dash or observer seat, no raw fiberglass will be seen. Everything will be finished out. For the floors, short strand fiberglass filler is being used to flatten everything out. Then a layer of glass will be laid down to seal everything in. There are 10 ribs that run vertically up the sides of the bow. Once the deck is removed again, those will be cut out and replaced. The rear ribs were reinforced and re-glassed.
2. The engine was run a couple more hours on the dyno. A little more timing and some tuning brought the horsepower up but the more data that was logged, the more it became apparent that engine was starving for air. My goal with the rebuild of this engine was to maintain the GT40 intake so that anyone who looked under the engine cover would know what PCM engine this boat shipped with. I didn't think the stock intake would be such a bottle neck but the ecm and dyno don't lie. When I thought about the money spent thus far on the engine, I could no longer put form over function. I decided to make the swap to a Holley High-Ram EFI intake. Throttle body size is moving from a 70mm to 92mm. New fuel rails and shorter distributor are part of the package. Hopefully the engine will be up and running next week.
3. I've started talking with Ron Tanis from Ski Boat Parts Online about him doing the engine and trans installation. I am still deciding if I am going to a 1 1/8" prop shaft. If so, he will also be replacing the strut. After watching his video's online, he's the man for the job.

Bummer on the GT40 , hold on to that thing they continue to increase in value pretty steady lately. Hopefully cam can make up for low end,, alot of volume in that plenum it really likes above 5000 rpm., small base circle distributor too I see. , Systemax I think would really match up good with the combo and keep a good hole shot.

Wideband sensor must not have been hooked up. It's not possible for the AFR to remain static across the RPM range.

I expected more but I have faith it will get better. Gonna try a different intake. AFR wasn’t hooked to the dyno. Dominator was controlling.

Looks like it is only picking up 25hp from 4000rpm to 5000rpm. Seems like it’s choking on something.

The 4” exhaust manifolds were used during the run. GLM is the manufacturer. https://www.cpperformance.com/p-30077-complete-exhaust-manifold-set-ford-v8-fits-4-hose.aspx

The cam is similar to X303 which needs 6200-6500 RPM to really work. It probably had not peaked yet.