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[Mountainman streetbob]

Does anyone have experience useing a 4 1/2 or 4 5/8 crank with the factory 110" SE cylinders? For street use under 6250 rpm? Almost NEVER above 5200 rpm? Low end torque-diesel-tractor type build!

I have read conflicting opinions on the matter.  Some say the cylinder bases are too short. Some say it's not an issue.

Does anyone have some proof? Empirical data? Firsthand experience?

[HD Street Performance]

No experience with that, but I do know the factory barrels will bore to 4.06
Trying to add stroke I suspect the shorter 4" barrel spigot would not offer proper skirt support.
Custom pistons are on the agenda.

[TorqueInc]

  I would suggest contacting Randy at Hyperformance     http://kingofcubes.com/

  You are probably no more than a custom set of pistons away from it working.

[HILLSIDECYCLE.COM]

Does anyone have experience useing a 4 1/2 or 4 5/8 crank with the factory 110" SE cylinders? For street use under 6250 rpm? Almost NEVER above 5200 rpm? Low end torque-diesel-tractor type build!

I have read conflicting opinions on the matter.  Some say the cylinder bases are too short. Some say it's not an issue.

Does anyone have some proof? Empirical data? Firsthand experience?

Why not just go to a 117"er, boring your cases?
With a Wood 6 cam, we built one for a client in the San Fran Bay area, a while back.
It was making 120 ft/lbs by 2200, and carried that untill 5300, with it's peak @ 3600-3700 @ 136 plus.
Didn't pull a big hp number, 119.5, but still not bad for a little .510" lift cam.
Scott

[Mountainman streetbob]

Thanks for the thoughts Guys!

I was under the impression these se 110" cylinders can be bored out safely to 4.065 max? I just want to safely  optimize the cylinder diameter.
While I have the cases apart to do the timken bearing and bore them for the cylinders I figured instead of putting $450-$800 insurance into the 4 3/8 crank I would step up to a 4 1/2 or even better a 4 5/8 crank and never need to touch the bottom end again.

I was warned by some people "who read or heard" that the spigot was too short. The same people have warned that a 4.625 crank was unreliable and created "piston speed" issues. I am not really worried about high piston speeds. This is going to be a  low rpm build, more of a "diesel" build. A hd tractor.... max rpm 6250? A Daily driver that isn't ridden hard below 2000rpm or above 5200 rpm.

I was leaning towards 4.000 x 4.625 as that would leave as much meat in the cylinder as possible, give as much stroke as possible, be as under square as possible. S&S offers forged pistons and overbore sizes for these dimensions. If I go 4.065 x 4.625 Headquarters has pistons and oversizes.

If spigot length is close, I was thinking I could add PEEK piston skirt buttons to support the piston skirts and help cut down on on the piston rocking/swaying/slap @ bdc.

I am figuring either a 4.0x4.625 or a 4.060x4.625 build should work great with a Leineweber T9, Woods tw-62 or woods 9f.

[HILLSIDECYCLE.COM]

If your looking for "agricultural power" take a look at the Wood TW-400.
Insta-torque............that will carry with a good head.
Scott

[HD Street Performance]

The same people have warned that a 4.625 crank was unreliable and created "piston speed" issues.

That would not be me, I am talking about a stability problem, same issue the SBC 421" motors can have if not addressed. The better solution is a case bore and HD bigger bore cylinders. The 113" is a very strong reliable motor. If I was talking a 117" I would skip that and move on to a 120 or 124 and then get that better crank you mentioned.

[TorqueInc]

  Sorta forgot about a local guy I did a little portwork and a valve job for.

  His engine had the recalled 110 heads and had a Indy put the all black cylinders and granite heads on a 4 1/2 stroke with a Tman 660 sm,I believe the pistons were CP with a dome

  So the 4 1/2 can for sure be done with the factory 110  4" cylinders

[HILLSIDECYCLE.COM]

4 5/8" stroke engines are very reliable, and piston speed is not an issue.
We've built a metric ton of 4 3/4" Shovels over the years, and actually quite a few Evo's and Shovels with 5" arms in them.
Once a guy rides/drives a 5" engine, he is totally upside-down with his thoughts on v-twin power.
Like turning a light switch on, any time, in any gear, but they cannot be lugged, or over-revved, and special care and feeding of those is required, but that said, we have them out there with over 30,000 miles on 'em.
Scott

[Razorback]

I don't see a huge cost saving here over using the SE bigger bore cylinders and having the extra spigot length support. The 110's are much shorter and the skirts will drop out the bottom of the spigot a bit and case bore clearance at that point along with piston oilers will need to be addressed. Sure the 110's could work but for less than the price of a set of slip on mufflers you can have a better setup with the bigger bores.

[Smitty2u]

I did the 4 5/8" crank and went with new cylinders as well. I was told the 110 cylinders weren't tall enough for the additional travel distance. Jugs bored to 4.06, which turns her into a 120. It does have a pucker factor when I run through the gears.

[Mountainman streetbob]

I am just trying to use the cylinders I already own and have $o into. I feel I need to do "something" about the 4 3/8 crank (plug and weld) Yet if I go to the trouble of "fixing" the crank while the case is getting bored and bearinged, Heck might as well put in a stroker crank...

Aw heck, might just put in the 110" kit with the untouched factory 08 4 3/8 crank, chain drive cam and do a low buck upgrade... See what happens. Add some roller rockers and adjustable pushrods to the ported heads and 58mm intake....

With the right cam 130+ tr
q/hp still easily attainable... A LOT LESS HASSLE AND POSSIBLE PROBLEMS....... DEFENITELY CHEAPER!

[HILLSIDECYCLE.COM]

I am just trying to use the cylinders I already own and have $o into. I feel I need to do "something" about the 4 3/8 crank (plug and weld) Yet if I go to the trouble of "fixing" the crank while the case is getting bored and bearinged, Heck might as well put in a stroker crank...

Aw heck, might just put in the 110" kit with the untouched factory 08 4 3/8 crank, chain drive cam and do a low buck upgrade... See what happens. Add some roller rockers and adjustable pushrods to the ported heads and 58mm intake....

With the right cam 130+ tr
q/hp still easily attainable... A LOT LESS HASSLE AND POSSIBLE PROBLEMS....... DEFENITELY CHEAPER!

Done correctly, that can/will build big power over a large rpm band.
Scott