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View Full Version : Which side iz tha rite side????



T-REX
06-05-2012, 05:34 AM
Toss'in around build'in a 3 cyl (1/2 a 2.4) to play in a local club wit....I wuz wnuder'in which(if any) wuz tha best side to use????...I know sum ov ya'll dun been ther dun that, and could save me sum exsperiment'in, and possibly sum parts....I have my own ideers, but juss wuz curious if tha runners ov this ole combo had a prefrence...Thankz in advance!!

Ron Hill
06-05-2012, 02:56 PM
Either side is OK, I think...Usually, people built the three banger out of a "BUSTED" V-6....So, they'd use the side that was good...

Personally, I was thinking half a 2.5 steel sleeve motor would be awesome....

Mike Wienandt, kind of got the SST 70 class going...and works for Mercury. He might be able to add something......His brother Trident lurks here, too...Maybe Jerry will post something....

Trident
06-05-2012, 05:12 PM
Lurk? Pretty hard for me to lurk...

Reverse rotation, as in running on an SSM 6 unit on a tunnel, the preferred bank is the Port side, 2, 4, 6. Whether that changes to the other side with standard rotation, I have no idea...

Actually, I think Mertons were the original guys to race a half six in SST70. With great success I might add.

My brother Mike ran a 1/2 2.4 in SST 70 and ran a really strong 1/2 2.5 in Formula 100.

I ran a 2.4 a few times, and I was amazed at how nicely it ran. No shake like I expected.

Hope this helps.

Jerry

Ron Hill
06-05-2012, 05:24 PM
I thought "LURK" was a nice word......I mean elephants hide in strawberry patches don't they...

Would and EFI work??????? I guess anything could work, but would it be workable....How about a Laser EFI?

Powerabout
06-05-2012, 08:41 PM
port bank due to stb exhaust makes the most power

Techteam
06-06-2012, 02:17 AM
IMHO you have to use port 2 4 6 as the bottom bearing gets its lubrication from number 6 and pumps the oil from there to the top bearing.

T-REX
06-06-2012, 05:40 AM
Thankz guyz, I figger'd they wuz a preferred bank...I never stopp'd ta thank about tha iol'in tha bottom and top bear'inz.....I kan't see any reason it wouldn't work juss az well turn'in in std rotation, do ya'll??

Trident
06-07-2012, 09:31 AM
I thought "LURK" was a nice word......I mean elephants hide in strawberry patches don't they...

Would and EFI work??????? I guess anything could work, but would it be workable....How about a Laser EFI?

Its a well known fact that elephants can hide in strawberry patches, but only when wearing red shoes.

Trident
06-07-2012, 09:52 AM
IMHO you have to use port 2 4 6 as the bottom bearing gets its lubrication from number 6 and pumps the oil from there to the top bearing.

Good point about the oiler hose. #6 has a seal ring on each side on the crank, but apparently enough oil leaks by to oil the bottom bearing and to be pumped via a check valve to the top bearing. Probably some help from Sir Issac, too, to get it down there.

Biggest reason we ran Port side is that bank makes more power in reverse rotation.

Don't know, spinning normal rotation...

Obviously, with running #6, oiling wasn't ever an issue.

tunnelvision07
06-07-2012, 10:45 AM
does anyone have a picture of a complete motor built like this. i would like to see one. it sounds very interresting.

Trident
06-07-2012, 11:23 AM
Don't have pix.

Anyone?

Externally, they don't look much different... just a 2.4 or whatever, with an aluminum plate in place of the Stb. cyl. head to save weight and hold the water in, and only one switchbox.

Other changes are internal. PVC sleeve plugs, dummy reedcages plugged with Devcon in 1,3,5. One side of each duplex carb plugged with a soldered inlet needle seat.

Pretty heavy for a three cylinder 1.2 or 1.25, but they make good power and run well.

Strongest one I've seen is Mike's 1/2 2.5 for Formula 100. That one has special sleeves and porting, etc. and made his Mod 50 Burgess way too small. Same boat ran really well with the SST 70 2.4 version.

tunnelvision07
06-07-2012, 02:36 PM
so you use the 2.4 midsection and lower unit?

Trident
06-07-2012, 03:00 PM
Most do use the 12" racing tower, any one of several versions, as the powerhead, V-6 cowls and SSM 6 gearcase bolt right up.

I have seen a few with the earlier die cast gearcase, not sure of the model number. Usually painted black, slightly smaller...

Hot setup for short course racing was 13 / 16 gears. Need a pretty small prop with 14 / 15 although that works, too. Maybe Ron can whip up some 15's?

Now, all the ones I've seen were for racing on true racing tunnels. I have no idea what else would work. Is there a short service tower for a 2.4? 20" would be shortest? Yes?

Anyone?

Fastjeff57
06-08-2012, 03:38 AM
Me too!

What do you do with the other 3 cylinders in regards to balance and other issues (like sealing the block and crankcase)?

Personally, I'd LOVE to build a looper 3 cylinder Merc with removable heads!

Sweet!

Jeff

PS: My homemade triple with external reeds really worked out great. With the same setup, the external reeds motor made nearly 1,000 more rpms at WOT and planed the boat off much easier (superior mid-range torque). Apparently, that stock Merc reed cage setup is a serious flow restriction.

Trident
06-08-2012, 08:04 AM
Surprisingly, to me at least, is you do nothing to balance except remove three rod / piston assys. They run nicely on the remaining three. No nasty vibration.

As for sealing, that's what the PVC sleeve plugs and dunmmy reedcages do. Those PVC sleeves get a blind or closed end glued in, which goes in toward the crank. Sleeves are flush with block deck dimension. The sleeves are lightly pressed and glued in. Butter 'em up, push 'em in. Wipe off any drool.

The aluminum head plate holds the sleeve from shifting out and holds water in. You can use a head on that side, but most remove it for weight savings.

The reedcages bolt up like normal next to the working ones, on the same gasket surface and allow nothing to pass through to the 'dead' cylinders. Carb venturis ahead of those dummy cages have no fuel, as inlet seats are plugged. Adjacent venturis on the duplex carbs are fully functional to feed 2, 4, and 6.

Hope this helps.

Fastjeff57
06-08-2012, 10:09 AM
..."Hope this helps. "

It sure does! I'm very interested in giving this a try--my next winter project.

A few more questions:

1. Do V-6 Mercs (that I nothing about--yet) use the same driveshaft as the in-line 6s?

2. On the V-6s that use two switch boxes (similar to those used on triples): can one simply omit one box and get the three cylinders firing in the right order? I assume that is how it's done with all 6 cylinders.

Thanks again!

Jeff

Trident
06-08-2012, 10:36 AM
No idea on driveshafts for inlines.

Anyone?

Everything I ran, SST 90, SST 120, SST 140 was on the SSM6. The 90 used a stub M/F spline adapter. The 1 / 2 six was a 2.4, same spline as the race V-6's

That ignition with two swtchboxes is, in effect, two 3 cyl. ignitions. I use one of that same switchbox on my 650XS FE Mod motor. The trigger tells which box to fire what cylinder.

Fastjeff57
06-08-2012, 11:04 AM
Gotcha! Thanks for the info.

Fascinating project!

Jeff

T-REX
06-09-2012, 06:49 AM
OK, Investigate'in haz begun...lol.......

I have a 2.5 block that I am use'in to exsperiment wit, but I will be use'in a 2.4 BP block for tha project...Instead ov PVC, tha unused rod slots will be welded up...Also, I will try and run NO water in tha unused side ov tha mota.....I will be use'in tha starb. side for exsperiment'in purposes(I kan oil tha bottom and top bearin's off any cyl used)....Exhaust will be directed out the back(sorta a horn setup)...Az for tha front, I will run a spacer(1") between the front half and manifold, with only the cyls used cut out!!...A 14 peddle front, and a XRI 14 peddle manifold will allow the use ov both venturi on the carb for each cyl(small venturi 135 carbs will be tha carb ta start)...Tha 2 venturi setup per cyl may be too much, but if I kan git it jett'd, it will allow good air flo....I'm kinna excited about this lil project.....I kinna like da odd stuff(maybe dats why I talk to Ron once in a while...:D)

Tha main reason I wanna do this iz wher I live iz a bote club that allow's any type 2 or 3 cyl to play....and, if this works out, I kan swap fron tha 3cyl back to tha Outlaw V-6....My lil bote iz a Comp(Kevlar) 16' laser, 260#s, It's gitt'in to tha dangerous point wit tha pump'd V-6's, and if this 3 cyl iz fun, I will feel a lil safer......I have a 2.7 stroker, "Z" port to hang on tha lil bote, but ain't made up my mind if I wanna pull tha trigger or not...:eek:

Thankz for all ya'llz input on this....Sho help'd me git goin on this!!!!:D

Oh yea, juss fer info purposes, I run a 15" mid, wit a big geercase...2:33 geerz...Tha big geercase iz quicker for 1/8th mile stuff....

Ron Hill
06-09-2012, 08:06 PM
Thanks, T-Rex for includinging in your list of "Crazy People".....Could you make a four cylinder this way?? Or are there no timing things for a four banger???

T-REX
06-10-2012, 06:56 AM
Hey Ron, don't go speckt'in me make'in chizk'in salad outta chikk'in poo, but juss ta set tha record strate, I did run a 5 cyl 2liter in Plymouth one yeer...made 3 passes, and turn'd 8100 rpm!!...I broke a ring, which broke tha pisson top off #5, so I removed the #5 pisson and rod, and ran it for points!!...it wuz still runn'in after tha race, and loaded on it's own power(which wuz down juss a tadd..:D).....Now who'z ya call'in krazy???...;)

Powerabout
06-10-2012, 07:29 AM
Thanks, T-Rex for includinging in your list of "Crazy People".....Could you make a four cylinder this way?? Or are there no timing things for a four banger???
Hi Ron
do you want to cut a V8 in half?

Fastjeff57
06-10-2012, 07:35 AM
Been done years ago with Chevy V-8s, but this guy didn't bother with al that (for a Bonneville record run). Kinda makes one think of the Merc V-6 on three holes!

Jeff

Ron Hill
06-10-2012, 09:56 AM
But most aren't insane.

One year we were getting ready for Parker and Ted Zahorski gave me a V-6 short block form Yamaha's warrantee motors to use.

My dad pulled it a part, ported it and put it back together. Five hours into the race a piston broke on number six hole. We pulled the head, took the rod and piston out and slapped it back together . We finished 4th in MOD VP.

After we got home, my dad was a little surprised that the piston broke. When he checked a little deeper, he realized he'd put a standard piston in a .030 hole. How a new warrantee block had one hole .030 over I never found the reason. Funny, my dad hones it, stuck a .030 back in, and she ran great...

As far as three banger to four banger......I always like "MORE BANG FOR BUCK CLASSES"....Like A Hydro, put an AXS restictor in an you are and AXS, put a J restrictor in and you are a J.....

I was just thinking maybe a three banger would be too slow for a 250 pounder, like me, but maybe a four banger would carry the weight...

I know half a V-8 is a V-4....

Jackson
06-12-2012, 04:26 AM
Does anyone have a pic of these 3 banger monsters?

Trident
06-12-2012, 07:42 AM
See post #11

They look just like a full V-6 with a flat aluminum plate in place of Stb. cylinder head. No plugs, coils or plug wires on those 3, of course.

sabine river killer
06-13-2012, 05:40 AM
1/2 merc done right

Powerabout
06-13-2012, 06:50 AM
Merc tried everything to make a competitive 3 banger....then gave up

Trident
06-13-2012, 08:34 AM
So, you never saw one of their Mod 50 / F3 loopers?

I think there were only a handful ever built, none sold as customer motors, and I'm guessing it had no real application as a service motor for sale to the public.

Instead, they sold those tractor motors, the 71 cube 3 cylinder 70, 75, 80, 90 and its bigger 4 cylinder brother. Very robust, but hardly a performance motor.

Then the later threes run well...

Powerabout
06-13-2012, 08:44 AM
Thats interesting
got any photos?

If OMC thought to build the M31 and Merc built a compeditor to that racing would have been great.

How many years did they race?
Cheers