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LakeRacer99
08-23-2002, 04:31 PM
So who is the expert on these motors? What years are the best? What are the differences? Did any of the 15" shaft motors have power trim? I am interested in building a good motor out of a pile of 3-5 motors, anywhere from 60hp to 75hp. Anybody have a short mid they need to get rid of?
Who's the daddy...

omc-v4
09-03-2002, 06:58 AM
no short shaft trim.60hp stuff not much good.
what are you going to do with it? this will give an ideal of the kind of stuff to use.the big l/u will run around 60 mph. the small one will run around 90.
beaver

Raceman
09-03-2002, 03:30 PM
"big l/u will run around 60 mph. the small one will run around 90."

What are you describing as big and what as small? I don't think a 3 cyl OMC has 90 MPH capability on anything except a Mod 50 boat which of course is faster than 90 and used their racing gearcase.

omc-v4
09-04-2002, 07:13 AM
ok maybe im off.it might havebeen 89 mph. dean droaz & roark sumerford hold the record set in 1980 in waco.roark is the daddy. the short shaft 75 has small l/u.jimbo ran 114 in his mod 50 sameday.
beaver

LakeRacer99
09-04-2002, 09:22 AM
Are you are talking about the "nitro" gearcase which was on the 15" shaft motors-smaller housing and had 15:xx gears. The 20" had a larger gear housing and 12:29gears.
or a speedmaster racing case?

Anybody know any carb differences between the motors? What about compression or glass reeds?

Thanks,

omc-v4
09-04-2002, 09:49 AM
the 1980 75 had larger carbs.plastic reeds are good.the motor dean ran had small carbs.the 80-75 had at trick enter exh. plate. the hi po head is good are you can mill a stock one.
beaver

omc-v4
09-04-2002, 10:02 AM
the big carbs came on the long shaft maybe 70 hp too. apba locked short shafts till mid 80s.

BarryStrawn
09-04-2002, 11:23 AM
SST60 kilo record is mid 90's and that is a production shifting case.

omc-v4
09-04-2002, 01:33 PM
the same unit that the se class used.
beaver

LakeRacer99
09-06-2002, 03:42 PM
Does anybody have the PN for the bigger carbs and exhaust plate? How do I tell one when I see them? If I am looking for a 15" 75hp would you say 1980 and newer were the best?

How hard is it to add power trim to one?

Thanks,
jason

Dave S
09-06-2002, 06:06 PM
Use a Force-Chrysler, I'm not sure what year power trim. It has a single ram and the pump can be located in the boat. If you need, I think I may have a long nitro case and hacksaw blade. Lets use our imagination. He He He He ;)

omc-v4
09-16-2002, 06:53 AM
I will have some shots of my latest 3 cyl. rig to post later this week.

LakeRacer99
09-16-2002, 08:31 AM
Cool V4, Looking forward to the pics.

Jason

David_L6
09-16-2002, 07:42 PM
Originally posted by omc-v4
the 1980 75 had larger carbs.
beaver

Do you mean 1980 and later models or were those carbs used only on the 1980 model engines?

David_L6
09-16-2002, 07:44 PM
Originally posted by omc-v4
the 80-75 had at trick enter exh. plate.
beaver


Are you talking about the plate that bolts to the powerhead (covering the exhaust cavity) or something in the mid section?

Is this a 1980 only part or was it used on 1980 and later models?

omc-v4
10-02-2002, 06:52 AM
1980 and later had the inter exh.plate the one close to the block on exh.side of powerhead. the big carbs. are on 1980 and later. but only on 20 in. motors. they also had better reed cages & stops. the reed assy. screws right to intake manifold.

Bruce Washburn
10-05-2002, 10:51 AM
I don't know where you would find the parts but I believe the mod 50 OMC's had a different side exhaust plate and 3 2barrel manifold. I think the head was also a little different. Jimbo's mod 50 was exceptional he could probably top 100 on a long course.
The SST 60 motor would prbably be a better base motor to start with. Some of the Formula Vee guys ran some slightly modified 60 motors that were pretty quick. The Yamaha 90 stuck on a shortshaft 60 mariner center section and lower unit would also be a good choice. Jeff Grigg could probably get you in touch with people that have ran both.
Good luck

omc-v4
10-11-2002, 07:02 AM
Boy we took your pile of 3cyl for a ride!Sorry about shots of my motor i have them in p/c but dont how to send them. The mod 50 stuff would be hard to use. I do run a mod 50 flywheel.

omc-v4
10-13-2002, 01:16 PM
pic of 3 cyl rear

Bill Gohr
10-23-2002, 02:56 AM
The best 50cu.in. 3's were the 1975's those had the good inner plates and tuner's. They came with high ring pistons light rods and lighter cranks. The short' scame with a different inner tuner plate than the longs. You'll have to find the original part numbers because everything SST'd to the later stuff. All the 75's came with the bigger carbs

wing nut
10-26-2002, 04:46 PM
i have a 1986 70hp evinrude. does this engine have the bigger carbs? or if i put the bigger carbs on will it perform any better??

scott

LakeRacer99
10-29-2002, 09:27 AM
OMCV4-
What size chopper are you spinning on that thing?
Looks like a Merc inline? Can you rehub a 15spline chopper with a 13 spine hub for an OMC 3 cyl?
Thanks,

Richard Fountain
10-29-2002, 12:08 PM
Tim Snyder makes towers for mod ob hydro's for varios engines. He is member of NBRA on yahoo groups kneeldownracers. hope this helps Richard K.C. Mo.

omc-v4
10-30-2002, 10:32 AM
Sorry pushed post instead of reply. Yes you can the v4 hub fits right in there. you can cut off the weed eaters or machine them down to fit in omc unit. Diameter is ok on v4s but has to be smaller for 3 cyl or remove trim tab and grind clearance in trim tab cavity. That one is 20 pitch in line chopper.

omc-v4
10-30-2002, 10:37 AM
The 65 Hp has lighter flywheel. You can take more wieght off of it in a lathe.

LakeRacer99
10-30-2002, 10:53 AM
Thanks for the info on the props and flywheel. Do you have anymore pics? What is the rig? Looks like an alum boat. Wahat are the numbers? I just picked up an old 13 Allison for my motor.

omc-v4
10-30-2002, 03:48 PM
Dont have any #s it was like driving something you thought you could control but had no time to wave at the crowd. Only had 2 in freeboard at transom could not back up porpoised till around 45 soon as that was over hello chine walk.I put it together to pull the grandkids around. I made about a dozen passes poped out 19 rivets out. Took it off put a short shaft 40 hp gale on her runs 28 mph.I have pic of p/h with mod 50 fly wheel & a side view of motor heigth try to post them sun. Is your allison 13-6? I ran s/s 55 hp on one i ran noa in ft worth Icould out run the 50 hp mercs. not easy. fred vought had a short back on his seat he was a tall bean pole he could get behind it and fly that 50hp merc man. start on his allison. We kiloed 50 in 1968.

LakeRacer99
10-30-2002, 04:08 PM
V4...Would love to see the powerhead pics.
My Ally is 13ft but it needs a complete restoration. It is a 1969.
Will have pics soon.

omc-v4
10-30-2002, 04:35 PM
Thats a good one the 67s had a wide pad 68 and up have the narrow one. A good solid hub dah cleaver used to be the best. I still have mine from 68 25 pitch got a million miles on it. Ran it on v4s 3 cyls allisons powercats hydrostreams checkmates glasstrons lasers im sure there is more all I can think of now.

Rusrog
10-30-2002, 05:36 PM
Do you remember the 14ft Allison that 'Mac' used to run? Red & white with cable steering??? Ring any bells???

Jim Schorr is trying to sell that boat and a lot of the other stuff that Mac had collected over the years. Mostly Merc stuff but I thought that you might be interested in the boat.

I'll give you a call in the next few days.

Russ Rogers
Ft Worth TX.

omc-v4
10-31-2002, 07:48 AM
Yes I know the boat . Find out more for me! how much where is it? How about my 5 in v-4 on it?

omc-v4
11-26-2002, 03:56 PM
Here are the stinger pics

omc-v4
11-26-2002, 04:00 PM
here is pic2

omc-v4
11-26-2002, 04:01 PM
here is pic3

omc-v4
11-26-2002, 04:05 PM
here is pic4

omc-v4
11-26-2002, 04:06 PM
here is pic5

Pete
11-26-2002, 04:28 PM
hey,
i was wondering if any of you guys new someone up here in ontario that had any of these 3cyl. for sale.
any info would be apretiated

Pete

LakeRacer99
12-11-2002, 01:43 PM
Hey OMC, here is a pic of my "pile"

LakeRacer99
12-11-2002, 01:46 PM
Here's a pic of the Allison that my short OMC will be one. As you can see, I have a lot of work to do on both.

David_L6
12-11-2002, 09:37 PM
Originally posted by LakeRacer99
Here's a pic of the Allison that my short OMC will be one.

Is that the boat that was on eBay not long ago?

LakeRacer99
12-12-2002, 10:58 AM
Well, it was on eBay a few months ago, but nobody hit the reserve, so I made him an offer.

omc-v4
12-12-2002, 12:33 PM
Racer looks like you got your work cut out for you. Your boat looks good. I went down to Houston afew weeks ago visted my motorhead Dave Burnett I have had his Banshee about 5 yrs now he wanted to put 75 hp v-4 on it. After talking about it we came up with putting 2-75 hp Stingers on it.He sent most all the motor stuff back with me. Now Im redoing Carlson CT-15 with souped up 100 hp 1967 Johhson,thinking about putting that 3 cyl off my tin boat on it? Also the PowerCat hydro with 235 hp on v4 Stinger mid with 1 to 1. Just need lots of time to do them.

David_L6
12-12-2002, 12:40 PM
As I recall that boat was in OKC, OK and it at one time held an APBA record of some sorts?

What size is the Merc? How do you think the 49.9 cube OMC will compare to the Merc? Are you going to run a Stinger type set up, i.e. small lower unit under a 3 cyl powerhead? Any mods to powerhead?

Keep us informed about this project. Looks interesting to me.

LakeRacer99
12-12-2002, 01:48 PM
David:
You are talking about a different boat than I have. That one went for more $ than I paid for this, but that may be in a little better shape. Also that one is a 14, mine is a 13. I don't think there will be any comparison between a 3cyl OMC and a 4cyl Merc. Even though I am a Merc lover, they can't touch the 3cyl loopers.
Now my power for now will be a good running 15" 65hp Triumph. I haven't measured the gearcase to see if it is any smaller then the longshaft model. Anybody know what year the introduced that case?
I will keep ya'll posted of the slow progress.

Here is the one your are thinking of...

David_L6
12-12-2002, 02:03 PM
Yea, that's the one I was thinking of.

What size Merc is that on your boat in the pic? You are right in that cubic inch for cubic in, the Merc can't touch the OMC. :(


I talked to a guy that used to own a dealership last night. As far as he can remember, the Stinger was just a 3 cyl. powerhead on a 15 inch mid with a 2 cyl lower unit.
(3 cyl 75 hp powerhead, 2 cyl. 50 hp lower unit, 15" mid section.)

LakeRacer99
12-12-2002, 02:38 PM
David:
The motor that came on my boat was a 50Hp longshaft, it runs real well, i got it on a Crestliner I am selling right now.
That is interesting what you say about the lower units. I have a 2cyl shortshaft on a stand in my garage. I wasn't sure if they would bolt up. I need to check that out.
I just need more time in the day.

David_L6
12-12-2002, 02:51 PM
A switch from a cross flow 50 to a looper 75. That should do it!

OMC lower units:

Splines on powerhead end of drive shafts are different, I'm told. I don't know if other end is same or not, but I'd guess that it is. We cut and couple drive shafts on our race motors all the time, so that is a possibility too.


Disclaimer: :cool:

Now remember, any information about OMCs coming from me is either what someone else has told me or a guess on my part. I don't know beans about OMCs.
(Except that some of the FE/SE guys have them smokin'!)

Hydrovector
12-12-2002, 03:01 PM
If I remember right. We tried a gear case set up with the 2 cylinder ratio on a 75 when we were racing back in the 70's and it did not help.

omc-v4
12-12-2002, 04:16 PM
It is a Glass Magic reverse hydro around 1959 or 60. I will get some pics on soon as I can.

omc-v4
12-13-2002, 10:38 AM
Here is the ct-15

omc-v4
12-13-2002, 10:46 AM
second attempt

Mark75H
12-13-2002, 04:02 PM
Thanks Beaver! Really cool!

Travis Fulton
12-15-2002, 07:34 PM
i know a guy who took a 2 cyl lower and put a 3 cyl power head on it?!???!!! it is a total secrete but i did get a snapshot of it once, i have looked at it briefly in the past and it looks factory 2 cyl trim and all but this guy is nuts and lets no one look too close. also i do have some good running 75 stinger carbs for sale if you are interisted??? :D

Travis Fulton
01-02-2003, 09:17 PM
i love 3 cyl's lets see some more pix......:D :) ;) :D :) ;)

LakeRacer99
01-10-2003, 02:23 PM
They are kinda sexy aren't they. Here is a cool shot I got of that Delta that was on eBay.
Hey Travis, where in MO are you from?

The Tank
01-11-2003, 12:34 PM
who bought that boat i would love to put that engine on my delta.

Travis Fulton
01-11-2003, 12:46 PM
i am in a town called salem, thats about 25 miles south of rolla if that helps? ;)

minto
08-01-2005, 11:41 AM
I saw this at a race meeting in the UK just 3 weeks ago.

Fast Fred
08-14-2005, 07:15 AM
this is an old thred Minto, that a nice shot of a Stinger :cool:

antslake
08-31-2005, 08:59 PM
I have a 1968 short shaft 55hp motor. It has the electric shift (boo)
I just found this web-site, and it is awesome.
I would love to rebuild this motor, and maybe hop it up a bit, and put it on something that will go fast.

Any ideas, or places I can start learning about these motors?
I have limited experience, but I have rebuilt 2 outboards, but I never got to hot rod anything.
I do hot rod cars.

I have a few blocks lay around, that I could put together something.
Loud and fast, thats what I want.

Dream boat? Allison XB2002 with a 2.5
I own a 19ft glassmaster runabout, with a 175 merc, that I rebuilt on it.
Old and slow, but its fun.

Mark75H
08-31-2005, 09:13 PM
The best way to hop it up would be to find a 75hp carbs, block, pistons & head

antslake
08-31-2005, 09:35 PM
So maximun, I could get out of it would be 75hp?
I have been browsing around this site for 2 days now, and I love it.
I think I will learn a lot here.
I am thinking about getting a 13' allison for it.

Is there any mods I can do to it, within reason, and reliabillity. Or should I just leave it alone.

Mark75H
08-31-2005, 10:13 PM
You can probably squeeze more out of it, but you would need those parts as a base for more.

Fast Fred
09-01-2005, 05:46 AM
you want to cut this in thare, a 70hp case is just as good, :cool:

Mark75H
09-01-2005, 06:25 AM
you want to cut this in thare, a 70hp case is just as good, :cool:

With newer pistons, carbs & head :)

If ya find the pistons, carbs & head .... there is probably a newer block with them :)

antslake
09-01-2005, 06:37 AM
Ok, exuse the ignorance, but what is that image?
Is that a template to expand ports?
Will I be changing timing by doing that?

Fast Fred
09-01-2005, 07:09 AM
it's aport map, if ya have a 70hp case, you would throw some timein into the exhaust, and boost port, but DO NOT mess with the transfur port timing,
on a 75hp case the timein of the ports is ware ya want it . other wise it will get vary peakey :eek: unless you are guna put it on a hydro, then we should mess
with all the timein :cool: you don't want the chickin stick rods or the small ristpin bullets, flat tops, run flat top pistons :cool:

Pete
09-07-2005, 04:02 PM
hey guys, Im looking to get rid of my 3cyl stuff.

ive got a bunch of stuff including :

2 cranks in good condition
6 mixmaxed pistons and rods
2 water jackets
2 sets of carbs
1 nitro gearcase in excellent condition
1 15" mid
1 cowel

ive got more stuff if anyone is interested i can send pictures upon request.

Thanks,
Pete

Travis Fulton
09-07-2005, 06:18 PM
send pix of stuff and prices


travis

1meanstream
09-07-2005, 06:40 PM
Sent you a pm

1meanstream
09-07-2005, 06:42 PM
Sorry the last post was for Pete

Pete
09-07-2005, 08:26 PM
I will have new pics as soon as i go up north. This is a pic of the gearcase, which is now painted blue.

Im not really sure on what the parts go for, but i would like to get somewhere around 1500cdn for all the stuff, i didnt list it all because im not sure what i still have at the cottage. Off the top of my head i have 4 or 5 heads, 2 in good condition and the others will all need to be sent off to the machine shop.

I have already had a few PM's about the gearcase, but no sale as of yet.

Pete

antslake
09-08-2005, 04:36 AM
What exactly is a nitro gearcase?

Pete
09-19-2005, 05:19 PM
a nitro gearcase is just the small gearcase you can get for the three cyl omc's. if im not mistaking the gear ratio is 1.87

Fast Fred
09-19-2005, 05:25 PM
this has got a Nitro foot on it :eek:

Fast Fred
09-19-2005, 05:27 PM
she's got 4 water pickup holes, I'm thinkin 1.84 to 1,?? :eek: :cool:

Pete
09-19-2005, 05:33 PM
fast fred looks like youve got a good collection of parts over there!

Im having a hard time getting rid of these.... can you recomend anywhere else i can advertise these things?

i really dont want to ebay them, and would like to see them go to use somehow. i want to help a racer out with this nitro case, but it seems everyone is getting out of the small stuff!

Fast Fred
09-19-2005, 05:34 PM
so Pete
your mid look like that but no l/u?, braket, exhaust block,ect.

antslake
09-19-2005, 09:55 PM
I take it these nitro gear cases are hard to come by?

Fast Fred
09-19-2005, 10:07 PM
if you don't keep tention on the shift linkage, and ya HIT the JUICE, when the shift dogs are slipin, it's guna make a window out the side :eek:
take that nitro foot slap a bobs big foot on it, cryo the bag out of it, and thats just as nice if not nicer than the SST 60 foot,which is this one :eek: :cool:

Pete
09-19-2005, 10:58 PM
they are worth what the market is willing to pay.

Fast Fred
09-20-2005, 06:26 AM
that is a vary good deal for that foot :cool: i'd buy it but right now I'm tryin to get my rig in the water for the CT river run, I got 2 Nitro's but I need mo, :eek: :cool:

antslake
09-20-2005, 06:31 AM
Sorry guys, this is all new stuff to me, so exuse the silly questions.
But can you buy these new, or is it no longer made?

Fast Fred
09-20-2005, 06:34 AM
no new ones, :eek: what thare is is what thare is :cool:

terry taylor
08-23-2006, 10:42 AM
hi FAST FRED I would like to know more about props for small gear case [nitro] max. dia. that can be used ,and average pitch used on 13 14/;boats and if you know gear ratio of nitro unit t hanks

Fast Fred
08-23-2006, 11:01 AM
21-23pich, someone said 13" of die gets under thare,runin 12 5/8" of die,:cool:

MtDoraGary
09-12-2006, 09:23 AM
David:
Even though I am a Merc lover, they can't touch the 3cyl loopers.

Can a 1958 Mercury Mark 78 hang with a 1976 Evinrude 75?

Mark75H
09-12-2006, 03:15 PM
The newer motor will kill the old one on prop selection. Speed is all about set up ... the old motor will be too limited.

gotboostedvr6
01-06-2007, 01:33 AM
next noob question which would you rather use....
late 70's early 80's 70 hp rude or 81 3cyl merc ?

both have no mods both will be run on a 12' semi V 410lbs

will be used for light ski duty and alot of fast runs

Raceman
01-06-2007, 09:11 AM
next noob question which would you rather use....
late 70's early 80's 70 hp rude or 81 3cyl merc ?

both have no mods both will be run on a 12' semi V 410lbs

will be used for light ski duty and alot of fast runs

The 3 cyl OMC will be faster, (not much different on that hull probably 2 or 3 MPH at the most) but the Merc may be easier to find parts for, and more plentiful initially. If you're talkin' about the Glastron from the other thread, you won't be making "fast runs" with it. They're neat as hell boats, but absolute dogs as far as performance goes. The G3 Glastrons are GREAT to restore from a nostalgia stanpoint but there's nothing you can do to make a performance boat out of em without cutting the bottom off and re-designing it.

I'd put the old shortshaft inline six Mark 78 you were talkin' about on it.;)

gotboostedvr6
01-06-2007, 11:56 AM
the OP in that thread had the old merc i kinda hijacked it :)
is there anything i can do to that hull to improve efficienty?
maby modding the pad or something

my G3 came with a 59 Mark 58A which was only 45 hp and 4cyl
http://i24.photobucket.com/albums/c24/gotboostedvr6/DSC01139.jpg

it has 130+ compression but im not a fan of these old motors i was going to restore this motor after i was done with the hull. i really want to be ready in the spring time

Mark75H
01-06-2007, 02:50 PM
Its usually prop selection that restricts speed on these older rigs, I wouldn't modify the boat until after I knew there was more motor and prop available

Raceman
01-06-2007, 03:10 PM
Actually I think it's the bottom. My brother in law bought one years ago and we put a 115 Johnson V4 on it. It was a pig. It's been so long that my memory is a little foggy, but I don't think we ever got it much into the 40's and then we never got it to quit porpoising at speed. There's no pad there, only a REAL shallow V and I looked at several others in addition to his and they all had a hook in the bottom.

gotboostedvr6
01-06-2007, 03:22 PM
well ive heard that you can mod the bottom to stop this porpoising? and also mabe add a pad
well would you say there are more props for 3cyl omc or 3 cyl mercs?

scud
06-13-2007, 07:31 PM
I put trim on a 15" stinger but it took a little work . I used the trim ,stern clamps ,swivel bracket which fits 55 hp twin from a 1979 20 inch transom model ,yes other years fit . you have to cut part the bottom of the 55hp swivel bracket off so it is the same length as the stinger swivel ,knock the bushing out of the stinger swivel ,then bore the bottom of the fresh cut 55 swivel out so the bushing fits in . Or you can make a set up like an sst45 has which would be lighter,but requires a lot of setback or cutting a huge hole in the transom.

I played around with these motors twenty years ago ,if you have questions i might be able to help. I even adapted a recoil pull start for one i think it saved about 40 lbs or so loosing the battery/wiring/elect starter .

MtDoraGary
06-13-2007, 08:39 PM
Actually I think it's the bottom. My brother in law bought one years ago and we put a 115 Johnson V4 on it. It was a pig. It's been so long that my memory is a little foggy, but I don't think we ever got it much into the 40's and then we never got it to quit porpoising at speed. There's no pad there, only a REAL shallow V and I looked at several others in addition to his and they all had a hook in the bottom.
You are correct about the bottom. I took the hook out, reduced the weight by a few hundred pounds, and it's still a pig. 50mph with a Yamaha 90. When it gets up around fifty, it skitters all over the place. I'm going to add a pad and some lifting strakes and let it go at that. Fixing the shallow V would be way to involved. I'd LOVE to graft an Allison or Checkmate hull under it!

MtDoraGary
06-13-2007, 08:41 PM
I put trim on a 15" stinger but it took a little work . I used the trim ,stern clamps ,swivel bracket which fits 55 hp twin from a 1979 20 inch transom model ,yes other years fit . you have to cut part the bottom of the 55hp swivel bracket off so it is the same length as the stinger swivel ,knock the bushing out of the stinger swivel ,then bore the bottom of the fresh cut 55 swivel out so the bushing fits in . Or you can make a set up like an sst45 has which would be lighter,but requires a lot of setback or cutting a huge hole in the transom.

I played around with these motors twenty years ago ,if you have questions i might be able to help. I even adapted a recoil pull start for one i think it saved about 40 lbs or so loosing the battery/wiring/elect starter .The Johnnyrude 75 is still sitting in the barn. I decided to take the easy way out and get PT&T by putting a Yammy 90 on back and painting it like a Stinger. Worked out fine!

gotboostedvr6
06-13-2007, 11:17 PM
have any pics of that yammy on your g3?

MtDoraGary
06-14-2007, 06:24 AM
Yes, but I don't have them on the web.

gotboostedvr6
08-26-2007, 09:40 PM
have those pics mt. dora?

kasshark
08-30-2007, 07:47 PM
Your Allison is a 69-71 mod. In 69 thay raced 50 merc. And 55HP. omc. 70-71, thay used 65hp. omc. All were 15 in. The omc used three blade 25 pitch cleaver. In 71 I used a 14x26 pitch 2 blade over the hub mercury prop. With a omc hub.

Johnny2piter
11-23-2007, 11:57 AM
it's aport map, if ya have a 70hp case, you would throw some timein into the exhaust, and boost port, but DO NOT mess with the transfur port timing,
on a 75hp case the timein of the ports is ware ya want it . other wise it will get vary peakey :eek: unless you are guna put it on a hydro, then we should mess
with all the timein :cool: you don't want the chickin stick rods or the small ristpin bullets, flat tops, run flat top pistons :cool:

Fast Fred, and others, thanks for your most valued input on these motors and drives. I just got a 1975 50 horse with what appears to be what may be the Nitro foot, even though it's the long leg, ESL75B.

Is there a port map for the looper twin and any suggestions on how to make it scream? I think I have sourced an oversize 78mm piston that has meat where I would have to cut a port hole in it but since the potential replacement piston candidate is basically a blank canvas have you got any ideas for a port map for the case and sleeve?

Would the stock carbs flow enough? Any other thoughts on flow from end to end?

Has anyone twin piped one of these? Searching around I saw this photo submitted as a reference for pipe design for a 45ss. Now the creative juices are flowing. Any help or input from others would also be appreciated. Love this place.

http://www.sacoriver.net/~red/amcm3.jpg

Fast Fred
11-23-2007, 12:18 PM
that port map should work some what for ya. the pipe will narrow the power band.:cool:

Johnny2piter
11-23-2007, 01:07 PM
that port map should work some what for ya. the pipe will narrow the power band.:cool:

Thanks Fred, this will be a fun build. :cool:

Mark75H
11-23-2007, 04:43 PM
At the peak of its development that motor was running about 100 mph in Formula E. I drove it once the year before when it was running about 89 or 90

smokin'joe
12-31-2008, 09:24 AM
I held the EP class record at 70.560 mph until the class became defunct. The 1975 powerhead and gearcase were best for EP, for SE it had no advantage over the later models with large skeg gearcase, heavier rods and pistons. When carburetors were updated, I found my 1975 carbs to be superior. In any case, no one could put together a faster stock 75 than I did. I'm looking for gearcase, driveshaft and downhousing. Otherwise, I have enough parts for a complete motor. Plus about 35 super lightweight pistons, all EP and SE legal.

Joe McCauley

php
12-31-2008, 01:19 PM
Joe I remember when you guys came to Rocks Pond S.C.in the last of the NOA days your 75s were fast.My dad built many OMC 75s Some were UIM engines that went to South America, He also liked the 75/75 carbs. I have a 75/75 downhousing an clamps make me a good offer if you want it. Danny Pigott

Ronster43
12-31-2008, 04:44 PM
I held the EP class record at 70.560 mph until the class became defunct. The 1975 powerhead and gearcase were best for EP, for SE it had no advantage over the later models with large skeg gearcase, heavier rods and pistons. When carburetors were updated, I found my 1975 carbs to be superior. In any case, no one could put together a faster stock 75 than I did. I'm looking for gearcase, driveshaft and downhousing. Otherwise, I have enough parts for a complete motor. Plus about 35 super lightweight pistons, all EP and SE legal.

Joe McCauley

Hi Joe. My brother, Mark Titus, and I ran a few times with you in EP in the late 70's/maybe early 80's. We could just barely break 70 in a kilo, but no more. I recall you telling us we would never do it in a Critchfield. You were right...and I got hurt trying. BUT we could get around the course! I kept the 1 1/4 mile. Memories!
Ron Titus

BTW - Do you have an old thrust bracket you might part with?

smokin'joe
01-01-2009, 09:27 AM
Dear Ron, I remember you and your whole family very well. Greetings to your brother, Sally and Jeff, please. I hope that all are well. My thrust bracket went to the Fla. panhandle with the entire boat before 2000. I don't recall the nam of the man who bought it, he put it in his marina as a photo a museum, let someone run it a few times. I also sold him all my props, all were very good. I had a special setup, i ran closed course, beach starts, with the same prop style that set the kilo record. Again, I hope your family's well. I heard from Edgar rose aftr posting a review of 'Iron Fist' on amazon. Edgar liked the review.

Best wishes,
Joe

smokin'joe
01-01-2009, 09:34 AM
The name Danny Piggott is burned into my brain because you guys had hot motors (Knoxville Boat Club). Apparently, your dad really knew how to build an NOA motor. All I had beyond stock was a .060" shaved head (180 psi) and light flywheel from an old 65 (I had very good self-modified props and boat bottom). As I recall, NOA motors were supposed to be stock like APBA but I asume that everyone else did a lot more. Send me an email about the downhousning price, please. I'm in Austria until early Aug. I got interested in outboards again last summer after 21 years, built a 1983 Johnson 35 that, with prop work, runs 41 mph on a 15' Allison bass boat (tiller handle). Could run faster.

Best wishes,
Joe
jmccauley@uh.edu




Joe I remember when you guys came to Rocks Pond S.C.in the last of the NOA days your 75s were fast.My dad built many OMC 75s Some were UIM engines that went to South America, He also liked the 75/75 carbs. I have a 75/75 downhousing an clamps make me a good offer if you want it. Danny Pigott

sheuninck
01-01-2009, 09:46 AM
70.2 in 87 stock with hi-perf head. Did not know about the 1972 flywheel back then.
http://www.youtube.com/watch?v=41b49FieyR8


Canadian Speed records
http://cbf.hyperboards.com/index.php?action=view_topic&topic_id=525&start=16

FE Aug. 1989 Dunnville 56.285, 1 mile oval, still stock with Titus Performance Propeller.

smokin'joe
01-02-2009, 04:41 AM
Resending, I think I made a mistake in reply earlier:

Dear Ron, I remember you and your whole family very well. Greetings to your brother, Sally and Jeff, please. I hope that all are well. My thrust bracket went to the Fla. panhandle with the entire boat before 2000. I don't recall the nam of the man who bought it, he put it in his marina as a photo a museum, let someone run it a few times. I also sold him all my props, all were very good. I had a special setup, i ran closed course, beach starts, with the same prop style that set the kilo record. Again, I hope your family's well. I heard from Edgar rose after posting a review of 'Iron Fist' on amazon. Edgar liked the review.

Best wishes,
Joe


Hi Joe. My brother, Mark Titus, and I ran a few times with you in EP in the late 70's/maybe early 80's. We could just barely break 70 in a kilo, but no more. I recall you telling us we would never do it in a Critchfield. You were right...and I got hurt trying. BUT we could get around the course! I kept the 1 1/4 mile. Memories!
Ron Titus

BTW - Do you have an old thrust bracket you might part with?

smokin'joe
01-08-2009, 12:23 PM
Danny, I need the downhousing and more, did you get my response earlier?
Joe





The name Danny Piggott is burned into my brain because you guys had hot motors (Knoxville Boat Club). Apparently, your dad really knew how to build an NOA motor. All I had beyond stock was a .060" shaved head (180 psi) and light flywheel from an old 65 (I had very good self-modified props and boat bottom). As I recall, NOA motors were supposed to be stock like APBA but I asume that everyone else did a lot more. Send me an email about the downhousning price, please. I'm in Austria until early Aug. I got interested in outboards again last summer after 21 years, built a 1983 Johnson 35 that, with prop work, runs 41 mph on a 15' Allison bass boat (tiller handle). Could run faster.

Best wishes,
Joe
jmccauley@uh.edu

smokin'joe
01-12-2009, 04:44 AM
Already found an empty gearcase and driveshaft. Is the downhousing complete with transom brackets, swivel brackets, shock mounts, tuner, everything?




I have a NOS nitro gearcase complete never ran that I would sell for $800 US, also have a new shell that I would take $200 for, and a 15 inch mid I would take $300 for.

smokin'joe
01-16-2009, 02:58 AM
Try Stone & Sons Marine in Houston, warehouse of parts for older motors.


Not to hijack this thread but I need some parts for my 78' 15" Stinger. Does anyone have the top and bottom motor mounts? I also need the long bolts that run thru the top mounts.

Please PM if you want to sell these parts.

Thx-

php
02-02-2009, 07:25 PM
Joe, There is a 13 foot Allison around here with a 75/75 Stinger on it. I am trying to track it down. I don't know what con. it is in ,sence i last saw it. I would not mine having the boat but don't need the eng. If i fine it i will let you know.

smokin'joe
02-03-2009, 04:18 AM
Danny,

Sounds interesting! Jay's old 14' and my first 13' are in houston in terrible shape, owners let them sit out in the rain. Balsa will have to be torn out and replaced.

Joe





Joe, There is a 13 foot Allison around here with a 75/75 Stinger on it. I am trying to track it down. I don't know what con. it is in ,sence i last saw it. I would not mine having the boat but don't need the eng. If i fine it i will let you know.

RMR260
02-16-2009, 08:57 PM
http://i44.tinypic.com/fbgv39.jpg

RMR260
02-16-2009, 09:01 PM
http://i43.tinypic.com/sfkq5u.jpg

RMR260
02-16-2009, 09:03 PM
sry about the size..but this is Todd Roddenberry in 87