Fordmods Logo

Compression Test Results 

 

Page 1 of 1 [ 5 posts ] 

 
 Post subject: Compression Test Results
Posted: Tue Oct 20, 2009 2:38 pm 
Getting Side Ways
Offline

Age: 31

Posts: 771

Joined: 20th Nov 2005

Ride: AU XR8 220 Manual

Hi all,

Just bought myself a really neat EL XR8 for a good price, runs like a dream since i did a big service on everything. the car is standard with an exhaust.

the motor is great, very strong and dosnt darken oil. i did a comp test for fun and it got a very even 135psi percylinder, how does this sound for a 165,000km car? is this normal/high/low etc?
Top
 Profile  
 
 
 Post subject: Re: Compression Test Results
Posted: Tue Oct 20, 2009 2:59 pm 
Getting Side Ways
Offline
User avatar

Age: 46

Posts: 3763

Joined: 25th Nov 2004

Gallery: 6 images

Ride: EFII 5.8 NOS TerroristGhia

Power: 274 rwkw

Location: Sydney Australia
NSW, Australia

A little low, should be up arind 220psi. Was it a wet or dry test. Try a wet test and see if you get any improvement.
Mine returned 120 even but was due to 8.7:1 comp from the head change.
Brett

 

_________________

The Terrorist ED Retired due to RUST.
The TerrosistGhia, EF Ghia 351 EFI 5 Speed.
Millennium Falcon, Sleeper EL DOHC 6 Speed Manual EFI LPG
Member#1131
I didn't Vote for Multiculturalism, DID YOU!!!

Top
 Profile  
 
 
 Post subject: Re: Compression Test Results
Posted: Tue Oct 20, 2009 4:39 pm 
Moderator
Offline

Posts: 14513

Joined: 7th Nov 2004

Ride: ford falcon au3 xr8

Location: a shit suburb in sydney
NSW, Australia

wouldnt 220psi relate to around 11:1 compresion ratio???
Top
 Profile  
 
 
 Post subject: Re: Compression Test Results
Posted: Tue Oct 20, 2009 4:45 pm 
Fordmods Addict
Offline
User avatar

Age: 31

Posts: 7958

Joined: 1st Jun 2005

Gallery: 13 images

Ride: Falcon

Power: 237 rwkw

Location: Melbourne
VIC, Australia

as long as it's even, it doesn't mean much.
leakdown test would be a more accurate measure of it's condition, but if it's not using oil and is strong i wouldn't bother.

 

_________________

ED XR8 Sprint - S-Trim, V500, 249rwkw
BF MKII F6 Tornado - 237rwkw

Top
 Profile  
 
 
 Post subject: Re: Compression Test Results
Posted: Tue Oct 20, 2009 4:59 pm 
Getting Side Ways
Offline

Posts: 699

Joined: 1st Jan 2006

Ride: Lots, all Fords

Location: Hamilton
New Zealand

135psi is fine, being even accross cylinders is another good sign. Your engine is fine. Roughly (very) speaking 135 / 14.7 = 9.18:1 compression ratio. Before anyone gets on their soap box, this calculation completely ignores induction system restrictions (volumetric efficiency) and cam profile. But it is a useful guide.

220psi cranking would be a high compression methanol type engine. Definately not a street engine.

 

_________________

XA Faimont 351C, AU2 XR8 Manual 5.0, DA LTD 5.0, Mk1 Capri 5.0, 1995 Mustang 5.0, EF2 XR8 Manual, EF2 Fairmont Ghia 5.0, AU3 XR8 Auto, AU2 XR8 Auto, AU2 XR8 Manual Ute, TE Cortina 5.0 Manual, DU LTD 5.0 soon to be manual

Top
 Profile  
 
Display posts from previous:
Sort by  
 Page 1 of 1  [ 5 posts ] 

Who is online

Users browsing this forum: No registered users and 8 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

 

 

It is currently Sat Dec 16, 2017 7:00 am All times are UTC + 11 hours

 

 

(c)2014 Total Web Solutions Australia - Australian Web Hosting and Domain Names