2L v-4 looper potential

[fyremanbil]

Just curious on the power potential of the 4-v looper on light weight hulls with 110 octane fuel. Will they make the same power per liter as the v-6? Will common v-6 performance parts and tricks work on the v-4? What is a reasonable continuous RPM for the production internals?

[ultrafast]

its all the same as the v6. Talk to manatee mauler, he had one on a little allison that would flat get it. He also has some top secret super trick parts for one. Buit seriously. He would pull a lot of v-6 s in 400-500 ft!!

[Laker]

You wont need 110 octane to make good power. :D
What year and HP do you have? What kind of boat?
Are you up to going inside the motor or just want to do bolt-ons?

[fyremanbil]

I'm looking at it as a possible motor to run on a Mod VP type circle boat. It would need to be competetive against the 2L Merc. The Mercs are limited by the rules in compression and porting, so they make about 200hp. Any 4 cyl motor is allowed unlimited mods. Will the v-4 make 200hp in endurance racing trim?

[brussrude]

I'm looking at it as a possible motor to run on a Mod VP type circle boat. It would need to be competetive against the 2L Merc. The Mercs are limited by the rules in compression and porting, so they make about 200hp. Any 4 cyl motor is allowed unlimited mods. Will the v-4 make 200hp in endurance racing trim?


What type of engine is the 2.0l Merc how many cyl ? 4 or 6 ??

[Cobra1racer]

What type of engine is the 2.0l Merc how many cyl ? 4 or 6 ??



v6 or the old inline 6, take your pick.

[Cobra1racer]

RULE 4: Classic Outboard-2.0 Technical Rules
ENGINES: (General) : V-6, Inline 6 and V-4 engines originally manufactured of 125 cu. in. or less. The engines must be naturally aspirated and run on gasoline containing no oxygen carrying additives introduced to the combustion chamber in any way. The maximum displacement for any engine shall be 126 cu. in. Unless specifically forbidden in the following, engines may be modified in any way.
MERCURY V-6 2.0 MANUFACTURED POWERHEADS:
1. V-6 engines must be of a standard production design. Special purpose engines shall not be allowed. Ports may be modified, raised, or enlarged, but shall remain in their original positions. Additional ports may not be added to the cylinders. “Behind the Liner”engines shall be prohibited, as shall finger porting, and Bridgeport exhausts. The cylinder head volume shall not be less than 26cc’s, measured using a surface gap plug. Combustion chamber quench area shall have a minimum of .100 band at the perimeter that is on the same plain as the deck surface. There shall be no fly-cutting of the heads allowed. Pistons must be of a flat top design with no dome or modifications made to increase compression. The engine may have no more than 6 carburetor venturis measuring no more than 1.327 at the venturi. EFI engines shall not be allowed. All critical or performance related parts/components (except pistons, rings, bearings, reeds, replacement electronics, and sealing components) shall be made by the OEM. Parts may be exchanged from other years or HP models. No other aftermarket parts or mixing of parts from other manufacturers shall be allowed.
2. MERCURY INLINE 6 & OMC V-4 MANUFACTURED POWERHEADS: These engines must be carbureted. Powerheads must exhaust no higher than the mid-section. Must comply with the general rules governing Classic Performance Craft Engine Rules.

[Cobra1racer]

There is a bonus side with running the V4, you get to run a lighter boat.

[LightNBug]

I have ask on BRF if the V4 looper fit into the V4 class rules and have not received an answer.

[BeefKid]

Laker is the man to talk to bout the v4 loopers!... he has his runnin with v6s:thumbsup:

[fyremanbil]

The v-4 is legal to run in the 2L class. The part which makes the v-4 unlimited is where it states "unless specifically forbiden below, engines may be modified in any way". Nothing is listed restricting v-4 mods.

[Cobra1racer]

You can work with the ports it has, you can't add any, like finger ports.

[racer]

You can add finger ports on a 4 but not a 6. Only restriction is no fuel injection. Bill Yes it will make the power, its keeping it together in the rpm range needed to make the power. I have built a lot of these in that range, tried to get Fred to run one but he has all the merc stuff already. How did your fathers back surgery go?

[fyremanbil]

Thanks Al, he's doing great. That's the info I was looking for, just wanted to know if it was viable. Any suggestions on making the rules more favorable for the v-4?

[baja200merk]

50 hp per cyl is almost easy.... 50hp per cyl WIDE FCUKING OPEN for a whole race is a different story.... :leaving:

[racer]

I think the rules are ok ecept the outboards have given up too much to help the car motors

[Cobra1racer]

I think the rules are ok ecept the outboards have given up too much to help the car motors


Thats for sure. There were a few big players in the 300.


I think Ross was trying to make every one happy, trial and error. I heard you were running in the low 90's as it was, the weight didn't kill you to bad. The GN boat was bitch'n, sounded great.
http://inlinethumb08.webshots.com/20743/2596612220103435598S600x600Q85.jpg (http://good-times.webshots.com/photo/2596612220103435598sDyvXG)