Using S pistons in E barrels on a 2.2L?

Magnum · Post by **Magnum** » Thu Apr 14, 2011 8:59 am

Hi

Please tell me that it wouldn't be a problem using 2.2S pistons in my otherwise standard 2.2E barrels?

I have heard that the S barrels had subtle dimples and of course the S rings are certainly different but surely it isn't a problem?

Many thanks

Jasper · Post by **Jasper** » Sun May 01, 2011 11:30 am

look up Wayne Dempsey's book site, how to rebuilt and modify a Porsche 911 engine.

Rds

johnM · Post by **johnM** » Sun May 01, 2011 11:44 am

Hi magnum

I have S pistons in my 2.2E. I was under the impression that E and S barrels were the same "biral" and the pistons were the only difference. If you put 2.2S pistons in a 2.4 you need to do some mods to stop the skirts from hitting the crank jurnals. Have a look at my engine build thread it may help.

http://www.ddk-online.com/phpBB2/viewtopic.php?t=17139

Kind regards

Magnum · Post by **Magnum** » Tue May 03, 2011 4:49 pm

Thanks John

I also understand that they are both Biral and therefore should be interchangeable, however, I have been told that S's had "dimpling" - maybe this is nonsense of only applicable to earlier models?

I thought it worth a check before planning/proceeding.......

Cheers

Jasper · Post by **Jasper** » Tue May 03, 2011 5:26 pm

Magnus,

I have noticed your comments on prefering E over S from a drivability / useage, I had a discussion with an Porsche engine builder and advised that an E was a nicer driving car because of the torque is broader and starts earlier. The S gets its power higher up the rev band between 4 /6k.

It's all down to the cam profile.

Get Wayne Dempsey's Book and it discusses this in detail.

Rds

Magnum · Post by **Magnum** » Tue May 03, 2011 5:32 pm

Thanks Jasper

I have read extensively - It's the bump in compression allied with some porting work (and without S cams and mfi pump changes) that will bump the horsepower up significantly (about 15%) to say 175. This has been widely documented and achieved by John M (above) and other(s) on DDK.

So driving charasterics of the E are maintained (but broadly enhanced with additional power of an S motor) without the pitfalls of the peaky S cams/motor.

Kind regards

Robster · Post by **Robster** » Sat May 14, 2011 8:37 am

Hi Magnus,

I have a 2.4E engine with 2.4S barrels and pistons with E cams (and carbs). Out of the book 2.4E should be 165hp. With these mods mine dyno'ed at 178hp so a definite improvement and car is great to drive with no flat spots from 2000rpm upwards.

no idea if there is difference between S & E barrels though (sorry).

DDK - Die Deutschen Klassiker

Using S pistons in E barrels on a 2.2L?

Using S pistons in E barrels on a 2.2L?

2.2 E & S