93mm pist/cyl replacement

[David Follett]

I believe I have the exhaust leak in the Cali cylinder heads sealed where air tubes were originally installed. I would like to replace the damaged dished 93mm P&S set. I have only found the same type. If I can use a flat top piston to gain more HP or a larger size where can I find them and what size would work?

[H2OSB]

I looked around and, like you, only found dished 93s. What about boosting up to a 1911 with 96s. They're not ultra expensive (or probably the same as you would spend for flat top 93s) and should drop right in. 94s wouldn't work because they're made for the longer stroke.

Assuming you have 41/34 valves, you would get a very nice boost in power with the least effort. 1.8s are a great basis for bumping up to 1911cc

H2OSB

[David Follett]

Thanks for the reply and info. 96mm P&L sounds great as long as they will fit. Stroke is 66mm, valves measure 41 and I thought 33 but probably are 34 and have dual 40 Webers. Any idea where to look for the 96 P&L's? Also any advice on a distributor. Don't have vacuum port for an advance.

[sideshow]

I run this kit https://aapistons.com/products/vw-porsc ... it-914-bus
w/the stock 66mm crankshaft. I don't think there is much else offered.

[David Follett]

Thank you for the reply and information. I've done some more research and not sure if the 96mm pistons have the same wrist pin location. Also there seems to be a concern that the 96mm cylinders are thinner and may have a limited wear issue. I did locate 93mm P&L on the Samba site and are available in both dished and flat type. Mine are dished. I would like to increase the cc size but concerned about the fit. Do you think a flat top set of 93's would improve performance? Existing cylinders had the metal seals on top and also at the bottom. I would not use the seal at the top again but what about the bottom seal? Is it necessary?

[H2OSB]

You can get 96s for both the 71mm and 66mm crank. Look through AAs lineup for examples. www.aapistons.com

H2OSB

[David Follett]

I do have 96's on order. Have not been able to work on engine since last October. Do I need to use a cylinder base gasket? There was a shim, did not look like a gasket, under the 93's I removed. Not gong to use a top ring/gasket. Assume compression will probably be around 9.? something and will need highest fuel available.

[VIPERGREEN76]

I don't understand why AA,can't make 93mm flat top P/C kit?

[farmer]

While the volume of the 93 mm set most likely os very minor, there is likely more volume in the bus version.
Over here, if we absolutely want to stay low displacement, we use 94 mm barrels and type 1 94 mm A pistons. It is not bolt on. You need to convert the rods to 22 mm pin bushing. Then you cet an 1830 cc . displacement with flat tops.

[VIPERGREEN76]

While the volume of the 93 mm set most likely os very minor, there is likely more volume in the bus version.
Over here, if we absolutely want to stay low displacement, we use 94 mm barrels and type 1 94 mm A pistons. It is not bolt on. You need to convert the rods to 22 mm pin bushing. Then you cet an 1830 cc . displacement with flat tops.

94mm type 4 barrels, with type 1, 94mm A pistons. Didn't know this set up would work.