heads up

[iwanajohnson]

I was looking at the second effort performance catalogue and saw a double plug head and a high compression head. Does anyone know what this does or how it enhances performance. I also have heard about milling out the heads to different cc's. How does this work and what does it do. i'm really interested in 3 hole omc motors but info on any other motor would be helpful. Anyone know anything about shaving the flywheel on 3 bangers?

[Jeff Akers]

Checkout this thread at hydroracer

http://www.hydroracer.net/forums/showthread.php?t=3862&highlight=flywheel

The photos have been deleted to save server space...I'll see if I can find an old pic and post it later.

[Roy Hodges]

I was looking at the second effort performance catalogue and saw a double plug head and a high compression head. Does anyone know what this does or how it enhances performance. I also have heard about milling out the heads to different cc's. How does this work and what does it do. i'm really interested in 3 hole omc motors but info on any other motor would be helpful. Anyone know anything about shaving the flywheel on 3 bangers?
You've been warned about milling flywheels , i know. You can mill a head , like on a 70 horsepower ,up to 3/16 ", (As long as you have flat top pistons) but you will need hy octane gas ,also the edge of the combustion chamber should be chamfered (beveled). The only double plug heads i saw was for big bore v-6's or v-8's .

[iwanajohnson]

You've been warned about milling flywheels , i know. You can mill a head , like on a 70 horsepower ,up to 3/16 ", (As long as you have flat top pistons) but you will need hy octane gas ,also the edge of the combustion chamber should be chamfered (beveled). The only double plug heads i saw was for big bore v-6's or v-8's .

I have only saw the double plugged heads on a v-6 also. wonder if it would be possible for a 3 banger, hehe. how much more does milling the heads out help compared to shaving the head? and can anyone explane a cc cut to a head to me. just tryin to learn some new stuff. And how are you guys talking about cutting a flywheel? I've saw them shaved down on the bottom , which makes the teeth thinner. I've heard of teeth chipping but i've never saw one esplode. I don't know how much it will help me so I don't think I'll shave it, but the heads, still interested.

[Roy Hodges]

I have only saw the double plugged heads on a v-6 also. wonder if it would be possible for a 3 banger, hehe. how much more does milling the heads out help compared to shaving the head? and can anyone explane a cc cut to a head to me. just tryin to learn some new stuff. And how are you guys talking about cutting a flywheel? I've saw them shaved down on the bottom , which makes the teeth thinner. I've heard of teeth chipping but i've never saw one esplode. I don't know how much it will help me so I don't think I'll shave it, but the heads, still interested.
Milling or shaving =same thing -=you do it with a mill.
I guess on some heads (cast iron CAR heads ,) they could be "surfaced" to reduce the combustion chamber

[iwanajohnson]

I had heard of miling and I have shaved heads before but I didn't know if milling ment milling out the domes. is that even possible? Nebody ever tried nitrous or a turbocharger on a 3 banger. it's all about the 1/4 mile:D

[Roy Hodges]

I had heard of miling and I have shaved heads before but I didn't know if milling ment milling out the domes. is that even possible? Nebody ever tried nitrous or a turbocharger on a 3 banger. it's all about the 1/4 mile:D
Sorry to correct you, Nitrous HAS been tried on a 3 banger. Out here in region 11. Back in late 70's. was sent out here by omc factory. It gave an instant 30 EXTRA horses. gave great accelleration out of corners ,installed on a SPORT E tunnel. If you're using flat top pistons , just mill whole head, on gasket side, of course.

[Skoontz]

You can take 36 grit sandpaper on a straight 2x4, clamp the head in a vice and take off all you need, then go to finer paper to clean it up. Just keep using modeling clay to tell how close you are getting. As long as you use even smooth strokes, it works slicker than snot on aluminum. Accurate? Not to far off what a mill would do as long as you move the paper correctly.

Sound butcherous, but when you are a kid with no money, lots of parts and time, anything for a mile an hour!

[iwanajohnson]

How about reliaility on a nitrous shootin motor? I would like to have that extra little shot of power but I don't believe it would be too practicle. would be nice put prolly not now. Sandpaper to a head, that takes some big ones. I understand the resource thing but don't think I could do it. so besides the chance of it exploding does shaving the fly wheel improve performance any at all? What kind of fuel pumps do yall run on your hopped up 3 cyl. omc's. I'm thinking of going with a electric holley.

[Skoontz]

You can also use an aluminum bastard and make sure you card file it after every 2nd stroke. Once again, make sure your strokes are even, using similar pressure across the whole thing. In Chicago, we called it a Pollack Powered milling machine.

[iwanajohnson]

it sounds like it works but you gotta understand how everyone will step back and say wow, sandpaper on a head, yea lol.as long as it works, that's all that matters.

[Jeff Akers]

Steve Bennson has done some heads for Formula E motors..He uses your "Good" head, fills in the stock chamber, cuts a new chamber and centers the sparkplug in the head...I think I was told this cost $500 ,don't quote me on that!... He has built "some" of the fastest FE motors in the country;)

I love the sand paper and 2x4 method Skoontz;) It works!
I finnish mine on a thick piece of glass and use lapping compound for the final cut.

[Ron Hill]

Jeff...would you "Walk Us' through the building of your Formula E motor...including all secrets, like serial numbers and such..as I know where tons of three cyclinder stuff is, and reasonable...but don't feel like digging if I don't know what to dig for...seems your KNOW what is needed for Formula E....

[iwanajohnson]

that sounds like a good ide, how do you build a FE motor.

[David Mason]

Being somewhat of a budget racer myself, my dad and I own a drill press and a lot of hand files. We do most of our own work. Boring, no, but porting, surfacing of the heads as some say, and all that. We use some methods that would probably make the high perfomrance builders cringe. But you know what what, money does not always win, sometimes sweat, tears, and a lot of time can overcome money. And the feeling of gratification you can get from it is second to none.

Flywheel Advantages - Lightweight means more acceleration out of the hole, maybe higher RPM in top end if you do other things.
Disadvantage - It will blow apart if you go to far or not enough. It very easily could throw it out of balance and ruin your crank eventually. Anyone who runs these engines in MOD knows they shake badly to begin with. OMC tolerances are not very good. They work great at 5500 RPM redlines in fishing engines, but turning them race RPM's brings out the horrible shaking. I would never use a flywheel lightend that got even close to the magnents. An easier solution would be to rig an ignition that does away with the big flywheel. Stone Racing makes a nice bolt on unit. I have one. They are out west in I think Washington.

So is it worth all the messing around ? It depends on how bad you want to race, and how competitive you really are. All the little things add up to one larger gain..........................

[Jeff Akers]

Jeff...would you "Walk Us' through the building of your Formula E motor...including all secrets, like serial numbers and such..as I know where tons of three cyclinder stuff is, and reasonable...but don't feel like digging if I don't know what to dig for...seems your KNOW what is needed for Formula E....


Oh boy, not sure I'm the guy for the job...I just finished my "ROOKIE" season:o

Like Mr Mason I am somewhat of a budget racer myself( the reason I whent with FE was, to "ME" working for a Rude dealer parts are cheap and the supply of fishing motors seemed pretty good) I did a lot of research on what has worked in the past in FE and made some adjustments to fit my needs and budget. I had very little outside work done. Most of the work was done by me by hand and over a long period of time.

As far as what blocks to look for? from what I can tell, any 49cui omc 3cyl will work. some say the 75 stinger is the ticket, some have sworn the old 65 is best..I started with a stock 70...

Most of the racers/engine builders I talked to were very helpfull when asked :cool:


There are many here on this website that have WAY more experiance with building an FE motor than me, hopefully they will speak up;)

[Mark75H]

There's a guy in the mid west that drag races jet drive outboards that has used nitrous on a triple, too ... I think his first name is Travis

A turbo is a hard deal on an outboard because you have to have a separate oil sump and pump

[iwanajohnson]

are you talkin about travis fulton in mid missouri? The motor I'm working on is for a jet drag boat. I'm trying to get about 6k-63k rpm's out of it and not much above that, above about 6200 your impeller starts to spin more water than suck, so above that is just wasted and can even slow you down. As far as his nitrous, never saw it run, theres a guy down here with us that run a merc tripple, 60hp with a jet. The motor runs really good out of the hole, but theres been several non bottled motors beat it past about 500 ft. we race a 1000 to 1200 ft drag. I have the other question on flywheel shaving. Are you all talking about an old 49ci flywheel or a new 56ci flywheel. I'm running a 56ci motor. Thanks yall for the info you guys are helpin me out a lot.

[iwanajohnson]

I got an idea, this could be completley out there and not possible or it could be the next big thing, could be a waste of money, I wanna hear everyones feedback on it. I was thinking about trying to take a 49ci motor, boring it .040 over, shaving the head .100. Putting in port work, finger ports, and drilling the head to put 2 plugs in each hole, and maby a mod 50 front half. basicly just hop up the motor with regular hop ups and exhaust and a dual plugged head. I don't know if a dual plugged head would do anything or just be a waste. let's see.

[David Mason]

are you talkin about travis fulton in mid missouri? The motor I'm working on is for a jet drag boat. I'm trying to get about 6k-63k rpm's out of it and not much above that, above about 6200 your impeller starts to spin more water than suck, so above that is just wasted and can even slow you down. As far as his nitrous, never saw it run, theres a guy down here with us that run a merc tripple, 60hp with a jet. The motor runs really good out of the hole, but theres been several non bottled motors beat it past about 500 ft. we race a 1000 to 1200 ft drag. I have the other question on flywheel shaving. Are you all talking about an old 49ci flywheel or a new 56ci flywheel. I'm running a 56ci motor. Thanks yall for the info you guys are helpin me out a lot.


I was refering to the smaller cubes. 56CI is not legal for Mod Outboard, even sleeved down to 49.9CI.

Sorry.

[iwanajohnson]

Yes, I see where the 49ci flywheel would fly appart, I believe how the 49flywheel would fly appart. I've saw the 56 flywheel but none of them have ever flew appart, so the flywheel shaved just helps the acceleration. I believe i might try it and see what it does, i've got a spare and a spare hood so i guess we'll see.

[iwanajohnson]

what's anyone think about a dual plug head, runnin 6 coils, and lettin it drink methanol???!!! Just an idea but wonderin what kinda compression I could get outa this settup. Thinkin bout runnin this one with some finger ports, some other port work, the head shaved, runnin big bore pistons, lightened flywheel, and mod 50 front half, on a 15" mid with long aluminum tuner, dry stacked. Think it could be pretty wicked. Nebody tried any of this or got ne thoughts.

[iwanajohnson]

what's anyone think about a dual plug head, runnin 6 coils, and lettin it drink methanol???!!! Just an idea but wonderin what kinda compression I could get outa this settup. Thinkin bout runnin this one with some finger ports, some other port work, the head shaved, runnin big bore pistons, lightened flywheel, and mod 50 front half, on a 15" mid with long aluminum tuner, dry stacked. Think it could be pretty wicked. Nebody tried any of this or got ne thoughts.

ok on the prevoius post i'm scratching the lightened flywheel part cuz i don't want a chunk of it coming through the hood and going through my skull, not a pleasant thought!!! Is a dry stacked exhaust the best practical 3 cylinder exhaust out there or is there something better. I've saw some runne and hustler type exhaust that dumps it all out twoards the block and none out in the mid. but didn't know how loud they were or how much more hp they gave ya. anyone got any thoughts, feedback or tried the dual plug methanol tripple idea, it's still a thought i've been tossin around and think it would make a killer drag motor, that's what it would be used for, but i'd like to know what everyone else says or thinks about it. leme know thanks everyone.

[Mark75H]

I have not seen the Hustler exhaust run any faster than production exhaust and it is very loud. The Runne exhaust dumps into the mid in the normal way and does not need to be any louder than stock while adding at least 10 mph to FE's.

[nbranews]

[QUOTE=iwanajohnson]are you talkin about travis fulton in mid missouri? The motor I'm working on is for a jet drag boat. I'm trying to get about 6k-63k rpm's out of it and not much above that, above about 6200 your impeller starts to spin more water than suck, so above that is just wasted and can even slow you down.
Your right on at the above 6200 idea. We run the 49.7 cu.in 3 holers and though not the fastest in the country we run very competitivly. We use a 3 pipe megaphone type exaust. we don't do a whole lot of internal mods but have found on the dyno that above 6200 the HP starts dropping off.

[JohnsonM50]

How about reliaility on a nitrous shootin motor? I would like to have that extra little shot of power but I don't believe it would be too practicle. would be nice put prolly not now. Sandpaper to a head, that takes some big ones. I understand the resource thing but don't think I could do it. so besides the chance of it exploding does shaving the fly wheel improve performance any at all? What kind of fuel pumps do yall run on your hopped up 3 cyl. omc's. I'm thinking of going with a electric holley.

Ive messed with and abandoned the flywheel cutting thing, on the 2 cyl motors I work with.. nothing gained worth all that work to start with and I was kindly warned too. If 1 exploded it would exit at about 200 feet per second + ... multi directional ... got a helmet? :eek: Thanks again Sam & Jim

[iwanajohnson]

I'm pretty sure the flywheel thing won't happen, atleast for rite now, i might cut a spare next summer but cash is gettin kinda thin so rite now just gettin the motor put togeather and workin, all that good jazz. Got a good oval port block if anyone would wanna trade it for a 56ci square port block. neone intersted pm me. I'm wanting to try this methanol motor pretty bad though.waste of time and mony possibly, best thing since sliced bread, maby, noone has one rite now though hehe lol just playin round yall thanks for the info.

[Freddie Webb]

Wilbur and Wayne Weeks drag raced a 3 cylinder on methanol back in the lated 70's early 80's.

[iwanajohnson]

and how did that work?

[Freddie Webb]

They were sucessful at drag racing. I have used methanol on the omc crossflows and intend to use it on my looper. I have never fooled around much with 3 cylinders.

[iwanajohnson]

I'd like to try it someday and see how it would work. gotta get the money in line first.

[iwanajohnson]

anyone got any wild or crazy mods that' they've been comin up with over the winter. like to see what kinda motors are bein built over the winter. I'll get pics up of mine when I get it done.I wanna see a pic of a nitrous motor nebody got anything or any good tips.

[David Mason]

It has been done in the Pro category in APBA. A fella from MI built up a 49 " OMC for 1100CCR. We talked about it all night at Constantine that year, he did his homework. I was supposed to take it out the next day on my boat and try to fine tune things, but I had other commitments I had that weekend. One of the secrets is the 3 megaphones...... if that helps you any.. Lots of internal mods as well. In Alky, there are not a lot of rules except bore and stroke.

[iwanajohnson]

really thinkin about this now and wondering if anyone has suggestions, tips, or any input. first question is. is it possible, practicle, and would it work to fill in a head, and re tap it for 2 plugs and 2 coils per piston on a 56ci omc. motor?

Idea number 2. bore out a 56ci omc motor and put 90hp sleves and pistons? would that work or does it defeat it's own purpose? and another question on that. what would have to be done to the head to run those pistons.

question 3. does it help or is it just a waste to have rods, crank, and flywheel machined and balanced? I know everything about flywheel's flying apart and coming through the hood, but I'm not worried about that. just the crank and rods.

fixing to start a yamarude racing motor and was wondering on a few ideas. thanks a lot guys. I know this is a lot of stuff to grab ahold of at once so just digest and take your time. thanks guys.

oh yea, I already got this on another thread. but anyone know what kinda mods would have to be done to yamaha pro 50 t@t bracket to fit to an old style 15"omc mid. thanks guys.

Like the nitrous idea to. shooting it in through the crank. i want somethin I have trouble hangin on to:D :eek: :cool: :rolleyes: