2.0 build

[volktek1]

I want to pull the engine in my 66 911 this winter to reseal it and do some needed maint. I was wondering what perfomance additions could be done on a low budget. I was told i could run the s pistons for higher comp, but i have not been able to verify that. I am not looking for a full race car engine just wanted to free up a little hp since the engine will be out. Any ideas, thanks

[Steve@Rennsport]

You already have good cams in there (Solex) but "S" pistons will help you with that CR increase. Be sure and have the distributor recurved to suit.

[Henry Schmidt]

If your looking to make a really pleasant engine that makes great power, install a set of AA 86 mm cylinders with JE pistons. 66 stroke x 86mm bore = 2300 cc
They come in two different compression ratios and are reasonably priced.
It will require that you machine the heads to suit but if you're doing a valve job it's an easy job.
I would run the lower compression (9.0:1 ?) with your Solex cams and you'll have a great little motor for slightly more than changing to "S" pistons.

I am leaning towards lower compression ratios because fuel octane is getting worse and I assume the Greenies will eventually figure out that lower octane fuel is the best way to get old cars off the road.

[volktek1]

I also forgot to mention that i do have webers on it. Is AA the brand on cylinders.

[Henry Schmidt]

Originally Posted by volktek1

I also forgot to mention that i do have webers on it. Is AA the brand on cylinders.

AA is a brand of after market Biral barrels.

[304065]

Search here under tag 901/05 for info on my '66 2,0 rebuild. 86 would be great.

[VitoV]

To save you a little searching, volktek, here's 304065's first thread on his 901/05 rebuild. It's a full exploration of what the options are with a small displacement 911 engine. A very full exploration-- I think he changes his mind in every post.

I am thinking about doing a rebuild on a 901/05 engine I have in the shop now. It came out of my '66 when it started to smoke a bit at idle. My rebuild will likely be pretty vanilla. I'm sure there are more horses out there, but I am just happy when my car doesn't make like I'm part of the county mosquito abatement squad. (And besides, if I built a big hp motor, I'd have to actually do something about those weedy brakes.) But I will be watching the thread to see what you decide on the bang-for-the-buck question.

[volktek1]

thank you all for the great information

[volktek1]

If i use the 86mm aa cylinders what kind of head work am i looking at? What is the stock compression ration of a stock 2.0?

[304065]

Henry can tell you because he does it all the time, but to go to 86 you would need to machine the cylinder-to-head mating surface to accomodate the 1970- seal. The later heads used a CE ring to seal to the cylinder, whereas the earlier 2,0 had a metal-to-metal seal with a gasket as the backup. You would also need to chamfer the combustion chamber edge like the later ones.

If I were going 86 (see the thread in which I consider many alternatives and then settle down on original ) I would use 2,2 heads or later. These have larger valves, the cylinder mating surface is already there. They have a smaller combustion chamber and a different valve angle which is better than the early heads.

Stock compression ratios were 9.1:1 for the 901/05 Normal and 9.8:1 for the 901/02 S motor.

[volktek1]

Thanks for the info