QSC compression height solved?

[DanHoug]

been trying to find recent info and have been unsuccessful. i'm trying to budget pistons + cylinders for a 2.1L... has the QSC compression height been resolved so they are now 36.7mm or are they still a low compression fit?

other than the expensive but good JE forged set from GoWesty, a tempting option, is there a budget set with the correct compression height?

-dan

[hdenter]

Rocky Jennings sells a set of rods that is bushed out to compensate for the low compression height. He also sells the pistons with better rings and balanced to match.

Hans
_________________
'79 triple white convertible bug
'84 sunroof vanagon
'85 weekender

[DanHoug]

thanks for the info, Hans.

i see AA Pistons claims the correct compression height:

http://vwparts.aircooled.net/AA-Piston-Cylinder-Se...-075dp.htm

any issue with the AA sets?

-dan

[jberger]

[DanHoug]

i wonder if a person would be better off just having a local machinist bore out the OEM cylinders to 95.5 to match the 2200cc kits? metallurgy is likely better and has been 'pre-stress tested'. for the price, a person can afford to just scrap/eBay the AA cylinders just to get the pistons.

-dan

[jberger]

[Robw_z]

I too question the quality of QSC pistons, not due to any personal experience, but the fact they got the piston pin height wrong, even if once upon a time, does not lend itself to trust.

The GoWesty JE piston set is currently $795.00 (it debuted at $695.00, a bit over a year ago after they started selling it separately from the 2.2 rebuild kit).

I wonder how much it is to have JE make a custom set of pistons, how hard it is to design them(in deviation if any from the factory dish), and how customized the GoWesty JE piston set is.

It may be a pipe dream but if some dedicated WBX rebuilders that all wanted to go 2.2 we could design a set and have a batch made up. Having the factory cylinders bored to 2200cc at a local machine shop seems like it would be easy. I know the poster above had trouble but he bored out to 2400cc.

Just thinking out loud. If I could have any piston set appear in front of me it would be a new set of DJ pistons for the higher compression.

-Rob

[jberger]

[Robw_z]

I stand corrected. Are you aware of why the shop had such difficulty boring out the cylinders? To the layman it seems theoretically much easier than your standard engine block.

-Rob

[modok]

Not knowing how they did it you can only guess. it would be a chore to hone them out without first boring close to size. To hone them by hand without a fixture would take hours each.

To bore the cylinder a fixture to hold it would have to be made, and that would cost quite a bit to make.
After it was made, I expect the cost would be 50$ per cylinder and for me it would be easy job, using amc C4 bed mill and ck-10 No fins in the way! What a treat.
Is that expensive or cheap? I don't know. The motorcycle guys think it's a bargain.

[jberger]

I had this done by a local Moto mfg shop. One who specializes in valve train performance and custom parts. Boring cylinders was not their bread and butter it was more of a pet project. The machinist said the OE cyl material was very hard and if he tried to bore it like other jugs it would get too hot and bore at a taper due to the uneven expansion. Therefore it took more of his time for each one. I paid them about $70 a bore if I remember correctly. There was a shop in Sonoma that would charge $40 or so for each one but convenience won out for me. As I mentioned, they turned out .0000" perfect so I'm happy. After that however I have build several 2.2's (2178 actually) using AA's I just have to go through several sets to come out with 4 good cyl's and even then they are not perfect.. still outside VW specs but not too bad.