TheSamba.com :: View topic - What size engine to build with 94mm pistons and case to use

Sun Dec 09, 2012 9:50 pm

I am new to building air-cooled engines. I got pair of J&E 94mm piston kit as a gift. I was wondering what size engine I could build and what case I should use? I dont know if I should use a stock 1600 dp and have it machined or go buy a stronger case? I want to start buying parts to get this motor built by summer.

Sun Dec 09, 2012 10:01 pm

Piston/cylinders are either A or B. A's for stock stroke, B's are for larger stroke. So, the size engine you can build will depend on which ones you have. Chances are JE are most likely stroker pistons. Common 94 stoker sizes would be 2165, 2276 or 2332.

Stock cases are more than able to be built up to 2332 fairly easily provided you have a later case, dual relief. If you have an earlier single relief case, it is a lesser candidate for building the monster engine.

Check the engine code on the case, and share, we can tell you what you have based on the code.

Sun Dec 09, 2012 10:09 pm

Ok longer stroke motor I will go with and who has good cylinders to use and what should I do to cool the motor?

Sun Dec 09, 2012 10:20 pm

If the engine is built correctly, it will not need any special cooling. Some stroker engine have lower running temps than stock. An original German doghouse shroud and German tins will be all you need.

You still need to know what those pistons are for. Stroker/non stroker. It depends on the distance from the center of the wrist pin to the crown of the piston.

Any barrels will work as long as they are honed for those particular pistons. AA and Mahle both make good enough barrels for street use. There's plenty here on The Samba.

Mon Dec 10, 2012 12:21 am

2 sets of JE p/c? Nice. You got two so u cam use a set why not. They are high quality p/c set. Got a size in mind? 74-86 cranks will need clearancing. Put some mo.ey aside for a.fully machined case. What ot comes down to is what you want, how you want it to drive, and how much cash u got to budget. Concensus is usually budget 700-800$ on heads and build as big as you can afford with the remainder.
Edit noticed its just pistons. If it fits, AA cylinder sets run about 105$ + shipping, mahle are 175 + shipping.

Mon Dec 10, 2012 5:26 am

jfats808 wrote: 74-86 cranks will need clearancing.

Actually 74mm needs no clearancing, 76mm needs very little (can be done at home with dremel).

To the OP, do a 2056 motor if you don't want to have your cases clearanced (94mmx74mm) or if you don't mind doing a little clearancing go for a 76mm crank and build a 2110. Get a set of DRD L5 heads, dual weber 40s, 1 5/8 header, and you'll be set.

Mon Dec 10, 2012 9:59 am

stevensj13 wrote: jfats808 wrote: 74-86 cranks will need clearancing.

Actually 74mm needs no clearancing, 76mm needs very little (can be done at home with dremel).

Can't make that a blanket statement on a 74.
We've had to touch up a few cases with a 74.
Sometimes depends on which rod you use.

Mon Dec 10, 2012 10:06 am

you dont need the je pistons, those arnt the je pistons your looking for, you can pass on those.I have a used knotched set of 90.5 with total seal rings that you want to trade me for the je's..........is my jedi mind trick working??? with those pistons I would use no smaller than a 86 stroke probably bigger, 88,90,92 honda rod motor.

Mon Dec 10, 2012 11:24 am

Sorry Mark not looking to trade or sell. I am looking to build a nice size engine. I am still strugglin on what case to use. I want a strong case to handle the power and not crack on me.

Mon Dec 10, 2012 12:37 pm

use a dual relief case, and put case savers in it if they are not there. Use 8mm head studs.

Clearancing depends on the stroke and the rods used. Good rods will require less clearancing than the others.