3rd Generation Specific Talk about 3rd gen RX-7's here.

Compression Ranges

Old Feb 17, 2003 | 11:00 PM
  #1  
JBurer's Avatar
Thread Starter
Member
 
Joined: Dec 2002
Posts: 83
From: Tampa, Florida
Default

Can someone tell me what psi ranges indicate acceptable compression on a 13B-rew when the engine is COLD?

The Hayes manual for the second gen says 85 is the minimum, but that is with a fully warmed up engine....



Any help is appreciated!

Best,

John
Old Feb 18, 2003 | 01:02 AM
  #2  
JT-Imports's Avatar
Senior Member
 
Joined: Sep 2002
Posts: 2,342
Default

Also matters what your RPMs are. I dont have the chart but I

would think its in the HAYES manual
Old Feb 18, 2003 | 01:11 AM
  #3  
Fd3BOOST's Avatar
Senior Member
 
Joined: Jun 2002
Posts: 9,725
From: La Plata, Maryland
Default

look here
Old Feb 18, 2003 | 09:39 AM
  #4  
vosko's Avatar
Super Moderator
 
Joined: Jul 2001
Posts: 17,839
From: NJ
Default

100psi is decent. my FD engine has 150psi compression on both rotors
Old Feb 18, 2003 | 10:39 AM
  #5  
9BASE3's Avatar
Senior Member
 
Joined: Feb 2002
Posts: 6,331
From: Frederick MD
Default

Originally Posted by vosko' date='Feb 18 2003, 09:39 AM
100psi is decent. my FD engine has 150psi compression on both rotors
Goddamn... I thought a 120-130 was like max?
Old Feb 18, 2003 | 10:43 AM
  #6  
vosko's Avatar
Super Moderator
 
Joined: Jul 2001
Posts: 17,839
From: NJ
Default

normal engines have 100-130. most are on the lower range...... what can i say judge ito is the man :bigok:
Old Feb 18, 2003 | 10:47 AM
  #7  
9BASE3's Avatar
Senior Member
 
Joined: Feb 2002
Posts: 6,331
From: Frederick MD
Default

Originally Posted by vosko' date='Feb 18 2003, 10:43 AM
normal engines have 100-130. most are on the lower range...... what can i say judge ito is the man :bigok:
Ahh. Sweet ***!
Old Feb 18, 2003 | 10:49 AM
  #8  
vosko's Avatar
Super Moderator
 
Joined: Jul 2001
Posts: 17,839
From: NJ
Default

my TII when it ran had like 95psi and 90psi. that engine ran fine. no hot start problems nothing. obviously the higher the number the better but if you get around 100psi the engine should run fine
Old Feb 18, 2003 | 11:18 AM
  #9  
9BASE3's Avatar
Senior Member
 
Joined: Feb 2002
Posts: 6,331
From: Frederick MD
Default

Originally Posted by vosko' date='Feb 18 2003, 10:49 AM
my TII when it ran had like 95psi and 90psi. that engine ran fine. no hot start problems nothing. obviously the higher the number the better but if you get around 100psi the engine should run fine
This might be a stupid question... But:



Why does low compression lead to hot start problems? Whats the heat have to do with it?
Old Feb 18, 2003 | 12:12 PM
  #10  
j9fd3s's Avatar
Senior Member
 
Joined: May 2002
Posts: 22,465
From: California
Default

well the ecu is setup to the "stock" compression specs, so thats one. the other thing is that the higher the compression the more torque you will have, so it will run and start better. thats not a really good way to explain it but i'm having a hard time putting it into words.



the heat basically acts like vapor lock, the fuel can boil in the rails and it might do other stuff too



mike

Thread Tools
Search this Thread

All times are GMT -5. The time now is 06:29 PM.