Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
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.
 

Welcome Guest ( Log In | Register )

> Compression Issues
deloreandude86
post 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
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
 
Reply to this topicStart new topic
Replies
VaccaRabite
post 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

User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Posts in this topic


Reply to this topicStart new topic
2 User(s) are reading this topic (2 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 27th December 2024 - 08:04 AM