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Mon Jun 24, 2013 5:48 am

Hi I wanted to know if its worth it to get 87mm pistons and cylinders
how much more power will my beetle make with the 87mm cylinders

Mon Jun 24, 2013 6:06 am

They are worth a few extra HP, but they will run hotter and they will not last as long as 85.5, so I don't think the sacrifices are worth the gains. I absolutely would not use them in a Bus or Type III

Mon Jun 24, 2013 6:14 am

vwracerdave wrote: They are worth a few extra HP, but they will run hotter and they will not last as long as 85.5, so I don't think the sacrifices are worth the gains. I absolutely would not use them in a Bus or Type III
I have a 1972 beetle with a duel port 1600cc and I wanted a bit more power, what other ways can i get more power and I the heat wont bother it because I live it Canada and its a lot cooler over here

Mon Jun 24, 2013 8:41 am

They don't run hotter by default, but they are more likely to warp if overheated and the 57cc's is not really worth the risk.

I would skip them and go with the AA brand 88's that are slip fit in the case and machine fit at the cylinder head. Your heads will need to be rebuilt or replaced anyway when rebuilding the engine, so it's easy enough to have them machined. Now you have an extra 100cc's for your efforts and nice thick cylinder walls.

Some mildly ported heads and a short duration cam like the cb cheater cam, extractor exhaust etc will make a nice increase in power. Add dual carbs and you will have even more power and better mileage too.

Mon Jun 24, 2013 10:00 am

Do the 1600cc and tickle yourself for 2 minutes = 1641cc :D

Mon Jun 24, 2013 10:06 am

Matthew wrote: They don't run hotter by default, but they are more likely to warp if overheated and the 57cc's is not really worth the risk.

I would skip them and go with the AA brand 88's that are slip fit in the case and machine fit at the cylinder head. Your heads will need to be rebuilt or replaced anyway when rebuilding the engine, so it's easy enough to have them machined. Now you have an extra 100cc's for your efforts and nice thick cylinder walls.

Some mildly ported heads and a short duration cam like the cb cheater cam, extractor exhaust etc will make a nice increase in power. Add dual carbs and you will have even more power and better mileage too.
wheres the cheapest dual carbs :D

Mon Jun 24, 2013 11:41 am

Cheapest - single barrel's like Kadrons. Best - port on port induction like Weber idf or Dellorto drla.

Mon Jun 24, 2013 11:49 am

WhiteJawz1 wrote:
wheres the cheapest dual carbs :D

Cheapest new dual carbs available...

http://www.thesamba.com/vw/classifieds/detail.php?id=1230752

Mon Jun 24, 2013 2:31 pm

My Mahle 87mm's lasted 3000 miles in a '74 bug. Oil temp never got over 210. They smoked terrible and had a bunch of blow by. I tore it down and they were almost .0025" out of round, slightly blue, and the top rings had lost their tension. I replaced them with stock 85mm AA's and gained a couple HP on my iPhone in car dyno app.

From now on I will use the AA 88mm's mentioned above. Super thick, and the heads probably need to be machined anyways.

Brian

Mon Jun 24, 2013 4:18 pm

Sounds like you got a terrible set, Brian. I have stock size Mahle pistons in my bug and upon replacing gaskets and whatnot I noticed that one of them had been in contact with a valve at some point in time before I purchased the car. They were and are still running just fine to this day. The only thing I noticed was it's incredibly hard to source out correct top rings for them. I purchased two different sets (don't remember brand but one was made in Germany and one was made in usa) of piston rings and neither top ring would fit inside the ringlands. So I reused the top rings that were in it, honed out the cylinders and put her back together.