Compression Issues |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Compression Issues |
deloreandude86 |
Oct 16 2011, 06:27 PM
Post
#1
|
Austin Burkhardt Group: Members Posts: 61 Joined: 18-August 10 From: Austonio, TX Member No.: 12,068 Region Association: South East States |
Alright guys, we've been working on this for a while now and I'm starting to wonder just what the hell. A few weeks ago I checked the compression getting readings like 36, 42, 46, etc. so we tore the engine down, honed the cylinders checked the valves, rings, gaskets and everthing else, put it all back together and we're still getting the same readings, given it does have a little more power than it did before, as far as compression goes, its the same. Now this engine is intresting because during the rebuild we found out that it was originally a 72 1.7L. However, the bore is 94mm? could this have an effect on compression? and if so are my readings close to what they should be? Also is there a special technique to doing a compression check on the 914 that differs from a standard engine?
Thanks |
VaccaRabite |
Oct 16 2011, 08:11 PM
Post
#2
|
En Garde! Group: Admin Posts: 13,616 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
When you do a compression test you need to make sure of a few things.
1) Valves must be set properly. 2) make sure the throttle is wide open. 3) the engine must be warm. 4) crank the engine until the tester does not go any higher. Don't worry so much about the number of cranks. If the valves are off, the engine is cold, o the throttle is closed - eash of these things could cause poor compression. My engine was a 1.7 that was turned into a 2056. The heads were cut to accept 2.0 cylinders, and those cylinders were cut to 96mm. My last compression test was 165psi. A properly built engine will have killer compression. Zach |
Lo-Fi Version | Time is now: 27th December 2024 - 08:04 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |