Tecumseh H50 Stroker

[delray]

Beauty. Thanks! Plenty of crank to reduce to fit the HS, but I see there isn't much room in there. I better pull one down and see how tight it gets. Hard to believe that under 2" is all the stroke that'll go in.

unfortunately that H crank ain't going to fit. it hits everything,block,cam,bottom bore...etc..
the only way that I can see making a stroker small block would to have the small block crank journal rewelded and then regrind with a off-set stroke. then you would have to make a tool steel billet cam and reason for that is because the stock cam is cast steel and you would have to machine some of the cast material between the lobes so the rod will clear and the cast material would be to thin to hold up at that point and tool steel billet would hold.

if you could get another .0625 stroke that would get you 2inch stroke. you might be able to max it to .125 with more stroke and that would be a 2.063 stroke and lets say you could bore it .040 over with that setup. that would be about a 213cc motor.

by the way if I every get to that point I will let you guys know about that build....:thumbsup:

 

[FirePowerMinis]

unfortunately that H crank ain't going to fit. it hits everything,block,cam,bottom bore...etc..
the only way that I can see making a stroker small block would to have the small block crank journal rewelded and then regrind with a off-set stroke. then you would have to make a tool steel billet cam and reason for that is because the stock cam is cast steel and you would have to machine some of the cast material between the lobes so the rod will clear and the cast material would be to thin to hold up at that point and tool steel billet would hold.

if you could get another .0625 stroke that would get you 2inch stroke. you might be able to max it to .125 with more stroke and that would be a 2.063 stroke and lets say you could bore it .040 over with that setup. that would be about a 213cc motor.

by the way if I every get to that point I will let you guys know about that build....:thumbsup:

I was sure the H crank would need substantial trimming on the OD and next to the rod journal, but hoped it could clear the cam, even if dropping to a .875 journal and B&S type stroker rod, shortened to the Tec. Oh well, offset grind may have to suffice. I've still not given up on a 3" bore though... LOL

 

[delray]

FirePowerMinis

I was sure the H crank would need substantial trimming on the OD and next to the rod journal, but hoped it could clear the cam, even if dropping to a .875 journal and B&S type stroker rod, shortened to the Tec. Oh well, offset grind may have to suffice. I've still not given up on a 3" bore though... LOL

I believe markus posted a picture of the h crank in a small block...…….not good.

ARC use to make a .875 4inch rod . I wish they still made that rod...:doah:

 

[OND]

Not much going on with this build , crank is still out getting turned down to fit the Clements rod . :shrug: Hope to get started cleaning and honing the block tomorrow.


[MENTION=31239]Havasu Dave[/MENTION] , Here's what I came up with as far as numbers for the Mikuni/Chikuni intake manifold.


Intake mounting holes C/C : 1.790


Briggs 5HP flathead holes C/C : 1.375
HS50 Tecumseh C/C : 1.400
H50 Tecumseh flathead : 1.865

Also I messed up... the slotted end of the intake was for the carb end , and not to the block.

 

[Havasu Dave]

Thanks Eric. How is the orientation on the HS as compared with a float type carb? Probably be hitting on the intake mounting bolts or nuts if studs are used.

 

[OND]

Dave , I'll check that out for you tomorrow . Didn't think to try that ?!?!
[MENTION=31239]Havasu Dave[/MENTION]

 

[Dr. Shop Teacher]

nice, well we know for sure we have two documented modified Tecumseh small blocks running. funny thing you two guys are the only ones I found. both you guys did a very good job on your builds with posting and a video running. OND will be another one when he is done with his build.....:thumbsup: it just seems like when I was doing searches for performance up grades on hs-motors I stumble across a lot of unknown finishes builds.

Hey....I built an H60/70 hybrid--H60 stroke, H70 piston and it's a torque monster and the TAV eats it up. That's my build off '18 engine...and I documented the build. Golly Neds, Brian! :laugh:

 

[delray]

Pete,i was talking about small block builds....:doah: but thats ok we will count your big block as number three engine build.. :laugh:...:thumbsup:

 

[OND]

Guys from Crankshaft Craftsmen called today and the H60 crank is done . Hopefully it will make it back before this Saturday.

 

[Dr. Shop Teacher]

Pete,i was talking about small block builds....:doah: but thats ok we will count your big block as number three engine build.. :laugh:...:thumbsup:

Dawned on me after I posted....that's ok...there's an HS50 sitting with my name on it.:thumbsup:

 

[OND]

Pete , Its a Tecumseh thread big or small ...post away !!!:laugh:

 

[Havasu Dave]

Pete , Its a Tecumseh thread big or small ...post away !!!:laugh:

There are a few people building small frame Tecumseh's now, and at least three with Dyno cams, and Briggs valve trains. :laugh: I'm not even bothering with a thread. I'll wait until it and the bike it's going on are done. Just in case it doesn't run.

Looking forward to seeing that fancy crank Eric.

 

[delray]

Guys from Crankshaft Craftsmen called today and the H60 crank is done . Hopefully it will make it back before this Saturday.

I wonder how much material you have on top a stock or over size piston for a H motor? you might be able to had the guy off set the grind little. for example .025 or more out. making it even more of a stroker engine. it would all depend on clearance and the thickness of the top of the piston. clearance would be the rod on how close it gets to the side of the case and maybe camshaft too. i'm sure if it was close you could still take off .025 material and not effect the integrity of the block or camshaft. that would be one crazy stroke out H-motor and with a over size piston.....:thumbsup: just think how much more cc's that would be.
eric would happen to know the rod length would be? and also do you know or anybody know if the last H-motors went to a thin style ring like the small blocks did and ohh-motors.

 

[delray]

There are a few people building small frame Tecumseh's now, and at least three with Dyno cams, and Briggs valve trains. :laugh: I'm not even bothering with a thread. I'll wait until it and the bike it's going on are done. Just in case it doesn't run.

well if we don't here from you in couple months? then we know she blew up...:doah:

 

[Badrooster]

Hey....I built an H60/70 hybrid--H60 stroke, H70 piston and it's a torque monster and the TAV eats it up. That's my build off '18 engine...and I documented the build. Golly Neds, Brian! :laugh:

Just a question. What do you mean by "The TAV eats it up."? Only curious.

Thanks.

 

[Badrooster]

There are a few people building small frame Tecumseh's now, and at least three with Dyno cams, and Briggs valve trains. :laugh: I'm not even bothering with a thread. I'll wait until it and the bike it's going on are done. Just in case it doesn't run.

Looking forward to seeing that fancy crank Eric.

Negative Nancy, hey?? LOL

 

[Dr. Shop Teacher]

Just a question. What do you mean by "The TAV eats it up."? Only curious.

Thanks.

The TAV really loves the torque being fed to it from the engine...sorry, wasn't clear. Hooks up nicely and firmly with the stock TAV springs.

 

[OND]

Looking forward to seeing that fancy crank Eric.

Thanks Dave ...and I can't wait to see it either ! As for the price that I had to pay to get this crank turned down and opened up width wise it better be perfect. :cursing:...………..:laugh:

 

[OND]

I wonder how much material you have on top a stock or over size piston for a H motor? you might be able to had the guy off set the grind little. for example .025 or more out. making it even more of a stroker engine. it would all depend on clearance and the thickness of the top of the piston. clearance would be the rod on how close it gets to the side of the case and maybe camshaft too. i'm sure if it was close you could still take off .025 material and not effect the integrity of the block or camshaft. that would be one crazy stroke out H-motor and with a over size piston.....:thumbsup: just think how much more cc's that would be.
eric would happen to know the rod length would be? and also do you know or anybody know if the last H-motors went to a thin style ring like the small blocks did and ohh-motors.

Don't know for sure yet on the piston delray I've been to busy rounding up parts for the HS build....but that's another thread ! :laugh: As far as in the hole , I will have no Idea until the crank comes back now . delray I have know Idea on the last H engines or the ohh engines , wish I had some to compare them with this build though. As far as cc's I'm hoping to pull start this engine as it is now , I would consider flat milling the head if the cam had a fancy compression release ...:shifty:

 

[OND]

Did a little quick checking on the stock H50 cam that came with this engine and was surprised , just using calipers to check it was like 268 / 272 lift a whole lot better lift than the HS engine . I'll try to get some solid numbers on the cam a little later in this thread.