I am building a 2056 out of a 2.0 core.

Which 96mm pistons and cylinders are the current favorite combo on the BBS?

I have heard in the past that people use new 96mm pistons (which kind?) and then bore out 94mm cylinders. I have two sets of core 94mm cylinders, one set is are rusty Kobelschmidt (KS) the other are Mahle (better shape overall but I broke a couple fins when I dropped one ). If I have them bored out can the fins be fixed or am I better off getting another cylinder?

I have also seen brand new 96mm piston and cyl. sets are available new. I recall people saying the quality of the cylinders was not very good. Is this true? An informed source told me they are ok.

I can't afford Nickies, otherwise I would use them.

B-Hole likes the asian made ones. If you have the $crilla, go nickies

I like them because they are local and cheap. I would prefer to use a bored out 94 with a KB 96 stuffed in it, but I have yet to get my hands on any (we can have them done locally) I sent 2 extra sets of cylinders to Jake so I could stock a set ready to go.


B

Is there anyplace local that can bore out 94's?

I guess this one is a goner...

Yep. Same machine shops who take forever to get our shit done.


B

Ok, I gotcha.

I have another set of heads, Brad. These are 10x better than the last set. No pics yet.

I wonder if those fins can be welded back on?

Find another set or another cylinder. Dont use that one.. and I wouldnt try to weld them up.


B

Are those two broken fins sole cause not to use those C's? I wouldnt think so...but what do I know?

Guess I should tell the story...

Pulled off the head and both cyls stuck to it. One came off with some light pounding but the other required me to beat on it with a 2lb mallet for a while. When it eventually broke loose it flew off the bench and hit the concrete floor.

At least this time I did not break my case when I separated it.

Does anyone know the typical costs of having 94's bored out to 96's? I will ask the machine shop when I drop off my heads, but I'd like to get a general idea of what to expect.

I think I paid 25.00 each. I'd send them to Rimco.

What pistons did you use with them?

KB 96's. I havent fired it up yet to know how it'll work, but I presume fine.

I just spoke to a machine shop that advised me to go with a new set of 96mm JE pistons and new cylinders to match. They did not know the manufacturer of the cyls. Apparently these run about $600.

They did not like the KB's and prefered forged pistons.

Anyone heard of this combo or have any idea who is selling it?

In a street engine KBs are better than JE!!

KBs are good. Your machine shop is over killing. KBs are as good or better than stock. JEs in a normally aspirated 2056 is way more then enough strength. The KBs won't let you down.

Do I have to provide the pistons to the machine shop that is boring out the cyls? When people say they run tighter clearances with the KBs what does that mean? Is this set up with the rings or the bore or both?

good question. aircooled.net asks $250 for kb's w/ rings. is there a better price that you have seen?

kevin

You should give them a sample piston with the cylinders. I think Jake mentioned he runs a 0.0015" piston to wall clearance. That's the measurement betwen the piston and the wall without rings.

That price seems fine.

You should have one machine shop do the overbore and check the pistons for roundness, and balance with the others, etc. Make sure the skirt clearance is within the recommended tolerance, I don't have this info on me at the moment. The piston vendor should tell you. He'll also give you the recommended gaps on the rings. Should be Hastings with the KB's.

what? i would have to mic all the new stuff?? the q.c. of these products had better not have me worried about being out of round.

kevin

QC? What the hell is that?
I have heard rumors of some pistons being waaaay outta balance straight from the factory. What you should do is double check everything before using it. Go to a deli and have them weigh the pistons and print out a sticker that says how much it weighs

Damn! I bought a set of Mahle pistons and they were 12 grams between the heaviest and the lightest. That's insane! The KBs I got were maybe 1.5 grams out. You have to check everything. If you trust someone elses QC then that's the part that will come back to bite you.

These days Mahle's suck pretty bad for balance. I consider a good set out of the box to be 8 grams out. I have seen up to 30!

None of the cylinders on todays market are worth a damn..thats why I bore stockers, they don't warp, don't leak and cool better!

Jake, does it matter whether the cylinders to be bored out are Mahle or KS? They are pretty much the same right??

Jake, what's your thought on a couple broken fin corners?

I know how you bring rods into balance, how the hell do you get 12GRAMS!! off a Pistion?

You send them back defective.

Do what I did and drop it. See what falls off.

I don't think aircooled checks the pistons out before they ship them to you. They just told me that the cyls are usually the problem and that they have not had a problem with the pistons.

I seem to remember the wrist pins are machined to match the weight

speaking of.. .Can anyone supply the part number of the pistons that are usable w/ the 1.8 stroke?
And any of the 1.7 / 1.8 cylinders can all be bored to accept the right 96's?
TIA
Robert O

Anyone got some o' them (pistons) they don't want?

What ring gaps are people running with the 96mm KBs for a 2056?

For that matter what skirt clearance also? I was expecting to get this info with the pistons but got some generic american iron numbers instead.