Mazda Rotary Club

General => Rotary and General Chit-Chat => Topic started by: L18M on September 10, 2011, 04:08:40 PM

Title: compression test results help pls
Post by: L18M on September 10, 2011, 04:08:40 PM
i just heard back from a guy with compression results of 100.
not sure what units and assume is done on normal piston compression tester.
can anyone throw me some figures to what is good and what units to be looking at.

many thanks :)
Title: compression test results help pls
Post by: L18M on September 10, 2011, 04:46:34 PM
oh its 100 psi on both front and back.
assuming a rotary compression tester is in bars then its 6.89 bar?

but not sure how accurate as unknown engine speed >.<
Title: compression test results help pls
Post by: Will66 on September 10, 2011, 04:57:17 PM
If it\'s on a normal compression tester then it\'s not much use.
Title: compression test results help pls
Post by: Jit on September 10, 2011, 05:04:10 PM
You need to know the engine speed
Title: compression test results help pls
Post by: Benedunn on September 10, 2011, 06:07:27 PM
as well as acurate figures for the 6 rotor faces!
 
mazda rotary comp testers give results in kg/cm2 as well not bar - tho theres not much difference :wiggle
Title: compression test results help pls
Post by: L18M on September 10, 2011, 06:10:52 PM
cheers guys :)
jit u passing nottingham anytime soon ;p
Title: compression test results help pls
Post by: Jit on September 10, 2011, 06:16:35 PM
Mazda tester gives values in KPa which is same as bar. Liam you not in Harrow anymore?please don\'t tell me this is your cursed engine? Give me a bell if you like when you got a spare min!
Title: compression test results help pls
Post by: m1tch on September 10, 2011, 06:27:40 PM
Yeah, can\'t be done by a normal compression tester, meaning the owner might not know what he is doing with a rotary engine!
Title: compression test results help pls
Post by: Jit on September 10, 2011, 06:36:13 PM
Just re read my post and since I can\'t edit it...

Mazda rotary testers give readings in 1x100kPa which is the same as bar
Title: compression test results help pls
Post by: Benedunn on September 10, 2011, 08:38:09 PM
ahhhhhhhhhhhhhhhh this explain soooooo much! i was always sure it was bar
 
but just so you know im not a complete idiot - im absolutly certain that results often come in kgf/cm2, PSI or kPa (= to bar as you say)
 
im not sure with the rx7 (i know the fds minimum is 85 psi) how it is measured in the hand book but the RX-8s results at 250rpm (standard for rotarys) need to be between 6.9 and 8.5 and im 1000000% certain thats kgf/cm2 and not bar - i needed to know because i get results in psi with my tester :cool - check the workshop manual if you dont believe me :p:Thumbs-up