Dishoner

[B Walker]

Zero weight gear oils and skeg removal are very low percentage gains.

The dude is literally running circles around him. That is pure grunting muscle on a 6HP scale that will not be overcome with relative minor modifications like that.

I am betting my left testicle that the "enemy" in this scenario is playing with a higher displacement motor and that Aqua Zombie has no chance with his '78 'Rude if it has the true bore and stroke of a 6HP which would be around 6 cubic inches total displacement at most for a 1978 vintage outboard.

BW

[Wayne mtl qc]

One thing which will make you slower for sure is he is running a flatbottom you a v bottom in the smaller hp range this will make a big diff . also check to see how deep you are and try to at least get the cavitation plate equal to the bottom of your boat or higher.If the motors are equal ,a flatbottom at maximum height would make all the difference.

It must be real close to silly season on HR

[Kev43V]

Low water pickup would just eliminate the drag of the impellor which is pretty minimal

As far as props go he would probably do better banging on the aluminum and cupping it a bit. A real performance wheels effect would pretty much be negated by the service foot hes pushing.

I still think he should shift the paradigm by challenging the bore and stroke of the supposedly 6HP Seahorse friends engine.

no substitute for cubic inches....except cubic dollars LOL

[Kev43V]

several years ago there was a thread about the 8 hp bathtub boat races. those guys were jacking the motors way up and running large props...
I always wanted to run a motor on oxy-acetylene. and just blend the ox. up until it was as high as I dared or the motor grenades. I have always wondered how much more(if any)RPM and power you could get

[johnsonm50]

several years ago there was a thread about the 8 hp bathtub boat races. those guys were jacking the motors way up and running large props...
I always wanted to run a motor on oxy-acetylene. and just blend the ox. up until it was as high as I dared or the motor grenades. I have always wondered how much more(if any)RPM and power you could get

Im thinkin fuel mix,,, so since your adding both from 1 nozzle it might work best as a closed injector. Fine tuning the mix would be fun.. You would have to think in terms of mix & velocity. Then of course how far you can go before it blows up. It would have to evolve into pulse metering so not to just run fuel thru the whole piston cycle. Enter -the computer age.

[Kev43V]

Im thinkin fuel mix,,, so since your adding both from 1 nozzle it might work best as a closed injector. Fine tuning the mix would be fun.. You would have to think in terms of mix & velocity. Then of course how far you can go before it blows up. It would have to evolve into pulse metering so not to just run fuel thru the whole piston cycle. Enter -the computer age.

Hmmmmm... I hadn't thought of it that way. I was thinking that as long as the "rate" out of the bottles (mix valves )was sufficent to fill the crank before the port opened AND you keep the pressure down to a resonable level with the regulators it would all be good. no carb. just a plate with a cutting tip brazed into it bolted in place of the carb. I would deff. want a finer O. valve than the one on my torch now though!

[johnsonm50]

Hmmmmm... I hadn't thought of it that way. I was thinking that as long as the "rate" out of the bottles (mix valves )was sufficent to fill the crank before the port opened AND you keep the pressure down to a resonable level with the regulators it would all be good. no carb. just a plate with a cutting tip brazed into it bolted in place of the carb. I would deff. want a finer O. valve than the one on my torch now though!

Right, some of those are sensitive- 'just tickle them knobs'. So if the crank case were to just remain pressurize how bout a bladder [like on a shallow well pump] in place of reeds to balance pressure. Thinking further that too much case pressure with no give & take might hinder running. There it would be a closed system of force fed gas with 1 thing missing... lube, separate injectors?

[Aqua Zombie]

Hooooowwww... eh hem... I mean, baaa... baaa... So the easy fix is to spline this powerhead to the output shaft and tuck it under the cowl and go I guess.

[johnsonm50]

Hooooowwww... eh hem... I mean, baaa... baaa... So the easy fix is to spline this powerhead to the output shaft and tuck it under the cowl and go I guess.

Yes, maybe.. The sleeved shaft would be easier than mounting the power head. You'll need an adapter plate & the cooling would need attention. Ive seen it with counter-sunk fasteners one way, studs the other. It could be overkill too. LoLs You also have to consider more HP doesnt always mean more rpm so unless you do something at the prop you could end up with a 10 mph dragster. Must admit, as a RaT maker I enjoy this thread.

[Kev43V]

Yes keeping oil to the bearings has allways been the biggest problem to over come.
drilling passages to the bearings and a seperate oil pump seems the simplist way to over come it.

[Mark 32]

this is the best thread I've seen in a while

[Aqua Zombie]

thank you Mark 32! I have some breaking info on my mill... It is a 1978 evinrude fishing motor. Ill post the serial # tomorrow morning if anybody wants to look at specs and parts on brp. The merc motor that I want to borrow the head off of just will not fit under the cowl. Not even close actually. So... I am shoping competitavly! Found a match for a powerhead that is mine to really do some voodoo on, and not compleatly ruin a perfectly good running trolling motor.... I think? I have a few prop options as well that I will be expereminting with. I'll get a line up pic of those posted soon as well.

[johnsonm50]

thank you Mark 32! I have some breaking info on my mill... It is a 1978 evinrude fishing motor. Ill post the serial # tomorrow morning if anybody wants to look at specs and parts on brp. The merc motor that I want to borrow the head off of just will not fit under the cowl. Not even close actually. So... I am shoping competitavly! Found a match for a powerhead that is mine to really do some voodoo on, and not compleatly ruin a perfectly good running trolling motor.... I think? I have a few prop options as well that I will be expereminting with. I'll get a line up pic of those posted soon as well.

It would take time to really go thru but I took a quick look at block-crank case assem's & find your '78 6hp stands alone. The nearest motors within 2 years either way are the 9.9 & 7.5 The 9.9 not even close but the '80 7.5 lokked a bit like it but the #s dont match.
The reed system on that looks like part of the problem, restrictive to some degree Id guess. I like to take off the carb, reed plate [remove the reed petals & dampers]. The put the carb on the manifold & reed plate & look thru backwards.
You might find some casting obstructions but looking to get more mix thru those reeds would be worth looking into. That alone wont be enuff but if you do other work you'll want it well fed.

[Tim Kurcz]

Mod guys in the making

Ahhhhhhh, you stockers are about to enter the dark side - just step a little closer. LOL!!! Been here since 1975 and enjoy the challenge. Now you know what Formula-E (disappointingly renamed 850) really means.

Tim

PS Would suggest getting the largest displacement powerhead that bolts on, mill the head, add Boyesen reeds, and a larger carb for starters - all external work. If you want to get more invasive, send it my way for some some port and exhaust work.............

[Aqua Zombie]

Model # 6804B. Serial # J0003785.