Viper is a blast to drive with 12" inline power

[FUJIMO]

[mach351]

Badass Charlie!!!

[dgscroggs]

What a cool build , nice job

[mrcrsr]

I ran a 78 Viper with a 78 1500 XS 28p chopper bolted to the trans. Best ever was 82 (pitot speedo) at close to 7k r's. Yours is a very fast hull imo.

For whatever the reason this engine won't rev, it's like it hits a wall at 63-6400. It spun a 26 chopper at 6400, 28 chopper 6400, 14.5 28 lightening et 6400, and the 14.5 30 lab cleaver 6400. Every time you go up in pitch the speed goes up, but it just doesn't rev higher than 6400. Adi 115, running the t2x tuner, and set timing to 22°

[Capt.Insane-o]

Eh you are probably up against the odd tuner length. My xs would hit the wall at 7200 with small props. Happiest at 6500.

[FUJIMO]

...just my .02, but its a 115 inline. its not going to have any more...above 64...

[FUJIMO]

...and i admire how nice & smooth that powerhead idles & accelerates. they don't all run that nice, so don't go starv'n it for cooling water or anything like that in the future. they can be steamed & never be the same. 76 mph is good for a 115 on a viper with that gearcase. the non xs gearcase of that era is 1 or 2 mph faster on the vipers & 16 actions we ran, but they can also steam a powerhead if the height isn't dialed in. if memory is correct, the standard gearcase was run a hair deeper, but ran faster, and did'nt aerate the slipstream like xs cases holes on the bottom did. jeeeez, that was a long time ago...

[FMP]

The bottom twin 8/10 reed assembly isn't helping much either

[hellbents-10]

Wow that is awesome!!! How much does that power weigh? "asking for a guy with a 16 Tuff"

[FUJIMO]

...272 pounds...

[Capt.Insane-o]

That set up doesn't weigh that much.

[FUJIMO]

That set up doesn't weigh that much.

...sssssshhhh...

[282]

What a set up like that worth? very nice

[Capt.Insane-o]

Loaded question....

[scott reierson]

mrcsr... Damn thats cool. Thanks for posting this. I'm running into that as well on my Vector and i'm doing very similar things. (Damn I want that cowl)

I've spoke to a few members here on my results. They have been very helpful.

I have a heavier setup. All original 2 owner boat. Recored as needed. Clean and dry 570lbs Before interior, rigging and motor.

I'm out of power 6000-6200. I can over trim it and spin it higher but she just lays down. i.e. 6800-7000 worked 26 chopper = 62mph

I'm running a fresh 1975 stock Merc 15" 150HP 1500 inline on a Vector. 21 degrees. Hi domes, stock 2:1 case with a Bobs cone. 1/2" below the concave part of the stock pad. 68-72 at 5800-6200 depending on props. Runnin Sea Star pro, solid mounts etc.

I've ran all the 22-30" inline six Choppers and Cleavers. Ran 27 & 29 SRX, 22-28 Yamy Drags. Pro Tech's and some others.

So far Mine likes the stock 14 x 28 3 blade over hub Merc ET. I'm amazed it spins this 70-72 at 5800. Using cell phone GPS speedo apps.

With a Stock 4 blade over hub 26 Pro ET its a whole new handling boat. Just don't have the power to turn over 66 mph. I have more plans for next season.

Doing a custom manual plate 3" setback fabricated to fit the 15" inline and 15" V6 merc

I'll reach out and give you a call.