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Posted by: Rhodes71/914 Nov 17 2004, 03:38 PM

My buddies down at my FLAPS have a set of P&C's for a 2.0 bus, brand new for a song. Can they be used, what is the difference

Posted by: Mueller Nov 17 2004, 03:43 PM

if I am correct.....really, really low compression

Posted by: SLITS Nov 17 2004, 03:54 PM

gallon size dish in the pistons. If you sing really good, will they give them to ya free (then you would be able to afford to modify them)? <_<

Posted by: Rhodes71/914 Nov 17 2004, 03:55 PM

if I am correct.....really, really low compression

Posted by: SLITS Nov 17 2004, 04:04 PM

Iffin ya really wanted to get tricky, you could mill the tops of the pistons & cylinders and then shorten the pushrods by a like amount to bring the compression up. That's what it would take.

Posted by: davep Nov 17 2004, 04:05 PM

If they are cheap enough, get them for the cylinders alone. Then do something imaginative with the pistons, mechanical art perhaps.

Posted by: Rhodes71/914 Nov 17 2004, 04:14 PM

So I can use the cylinders with the pistons I have now? They want $200 for the set.

Posted by: Root_Werks Nov 17 2004, 04:15 PM

Yeah, I thought the cylinders were the same? Might be worth it for those, then just use your pistons. Where's Jake when you need him?

Posted by: Aaron Cox Nov 17 2004, 04:29 PM

run some KB pistons with those new cyl's...

Posted by: Cloudbuster Nov 17 2004, 04:30 PM

I'd buy the set just for the cylinders -- if they're OEM (Mahle, Kolbenschmidt?) Look for a part number at the base of the cylinder, where the fins are the shallowest.

Posted by: Rhodes71/914 Nov 17 2004, 04:46 PM

They are Mahle, I am going to swing by later this afternoon and check the part #. Ooh shiny new cylinders.

Dan do you see what you have done, this was going to just be a clean up. Now the heads are off and I am thinking about new P&C's. Thanks man.

Posted by: Rhodes71/914 Nov 17 2004, 10:13 PM

So they have 2 sets of 94mm P&Cs. One is has deep dished pistons and are made in Brazil and stamped with 029.198.075 vw #. The other set has flat top and are Mahle, according to the guy there when I was in the second time. No number stamped like the other, there was C-70 LX in the same general area as on the other set.

The guy that was doing some checking on them for me was gone so we'll see what he has to tell me.

What else can I check on these, would really by nice if they could work.

Posted by: SLITS Nov 17 2004, 10:37 PM

Take the set with the flat-tops - those shoud be the "Euro" high compression ones. In the top of the piston, the size might be stamped - 93.???mm. Hopefully, they will say "made in Germany".

Posted by: Joe Ricard Nov 18 2004, 07:44 AM

I don't believe anything any of you guys say

I have been running used Mahle Bus pistons with 10 cc dish for 2 years. I have no problems with them and the engine makes LOTS of power. Now for the disclaimer. I am not running recommended deck hiegth. about .010 less. .500 lift 290 duration cam ported and polished 2.0L heads exiting out 2.0L SSI Bursch exhaust. 44IDF carbs. This car rips and I really don't know how fast it will go but I did see 120 the other day. It will cruise all day 85-90 and makes near 28 MPG.

Posted by: davep Nov 18 2004, 08:38 AM

The bus pistons will cause a loss of compression, so you won't get the power that the stock or euro pistons will provide. The lower power of the bus engine was also due to the bus heads. Bus pistons and 914 heads would be somewhere between a bus engine and a US 914 engine. Still, I'm not sure that $200 for a set of cylinders is a good deal. Not exactly a giveaway deal really. I picked up a set of used euro P&C from Jake for about $75. Needs cleaning and a new set of rings. New cylinders would be a nice addition but, being a CSOB, I might be willing to offer $100.

I'd think that a set of overbored 93mm cylinders from a 1.8 would be a good path. Nicely aged cylinders properly done should be okay. Just forget offhand if they fit the 2.0 heads. Anyone know for sure? This was just a seat of the pants brainstorm, so I might be all wet.

Posted by: Bleyseng Nov 18 2004, 08:49 AM

They have the same outside diam. as the 2.0l and 96mm.

Geoff

Posted by: Root_Werks Nov 18 2004, 09:13 AM

Posted by: Rhodes71/914 Nov 18 2004, 03:56 PM

The flat top ones ende up being different. Different wrist pin size, deck height. So I'm moving on. Maybe just new rings and put it back together. $200 I could have done $500+ is out, oh well.

Posted by: Rhodes71/914 Nov 20 2004, 02:34 PM

I'm not leaving these P&Cs yet. Some of you have said that $200 was to much, these aren't used they are brand new. I have heard that be changing the deck hieght I can change the compression.

There are currently shims between the top of the cylinder and the head, are these stock. Can I remove these thus making the deck height less.

Maybe I should just use the cylinders, put new rings on the pistons I have now and call it good.

What do ya think.

Posted by: davep Nov 20 2004, 03:56 PM

If it is worth it to you, then by all means get the new cylinders. As Jake has repeatedly said, ditch the head gaskets. But, you do have to watch your deck height, it is there for an extremely important reason: you don't want your pistons hitting the heads or the valves, and the con rods stretch significantly at high revs. So, read up on deck height. Do a search here, it has been discussed before. Get the proper info from Jake, don't make a mistake.

Posted by: SirAndy Nov 20 2004, 04:10 PM

Posted by: Joe Ricard Nov 20 2004, 08:35 PM

I think everybody has provided a piece to the puzzle. Now you have to weed thru it and figure out what to do.

Cheapest option would be to get new rings. However you can't just throw new rings in shiny cylinders. The cross hatching is there for a reason, that being to wear in a micronic level to conform to the new rings.

Cylinder hones from NAPA are about $27.00 Put it in a drill and be carefull not to be over zealous. Just brake the glaze.

If you really want to do it right you need to measure your pistons and measure the cylinders there in a factory spec that I don't retain in memory. A machinist can do this for you and hone the cylinders if they can be done within the wear limit.

Then again them new cylinders would fix this but should also be measured. So you see doing this right is not cheap nor easy if you don't have all the micrometers.

NOT to mention having tons of opinions from us knuckle heads

Posted by: Rhodes71/914 Nov 21 2004, 04:14 PM

Thanks everyone for all the input.

I am currently proccessing it in my feeble brain and will let you know what comes of it.

Leaning towards honing and new rings.

After a drive in a 3.0 six today maybe I will start saving my money. And in 10 years maybe I will have enough.