| FAQ |
| Members List |
| Social Groups |
| Calendar |
| Search |
| Today's Posts |
|
#1
03-24-2017, 07:05 PM
|
|||
|
|||
Ram Air II, III & IV compression ratio and group number?
I was thumbing through the 68/69 assembly manual for GTO/GP and I came across something interesting and odd. Page 6-3 (9795602) has an engine assembly usage chart. I noticed the 68 RA II engine codes were still listed on this chart and the group number is L85. I had previously thought the group number was L67.....so now I am a bit confused because I've never heard of L85 before. Is that a real number and if so, is that correct for RA II?
Also notice the compression ratio for the RA II is 10.5 while the RA IV and RA III (auto) are 9.8. Isn't that strange? I thought the III and IV had the same compression ratio as RA II but maybe I was mistaken. One more weird thing on this sheet..... Original document date is 4-7-67, released on 5-5-67. That tells me the engineers differentiated the RA II from the IV even back then. First revision was in Jan of 69 where they added the L85 designation. If L85 is correct for RA II (judging by the compression ratio and engine code that would seem to be the case....), then why revise this chart in Jan of 1969? Was it possible to order the RA II in 69? I never thought that was the case but it kinda appears that way just by looking at this chart. Any thoughts? Is there something simple I am missing that is causing me to be confused? 
|
|
#2
03-24-2017, 07:40 PM
|
||||
|
||||
|
That is for the RA V (L85) engine.
__________________
John Wallace - johnta1 Pontiac Power RULES !!! www.wallaceracing.com Winner of Top Class at Pontiac Nationals, 2004 Cordova Winner of Quick 16 At Ames 2004 Pontiac Tripower Nats KRE's MR-1 - 1st 5 second Pontiac block ever! "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." "People demand freedom of speech to make up for the freedom of thought which they avoid." – Socrates |
|
#3
03-24-2017, 08:57 PM
|
|||
|
|||
|
Quote:
|
|
#4
03-24-2017, 09:00 PM
|
|||
|
|||
|
Quote:
What about the compression ratio chart? Are the RAIV engines really only 9.8 ratio? I thought they were 10.75 range... |
|
#5
03-24-2017, 09:10 PM
|
||||
|
||||
|
I'd say that was the real CR and not the 'advertised' ratio?
(as reported to magazines etc)
__________________
John Wallace - johnta1 Pontiac Power RULES !!! www.wallaceracing.com Winner of Top Class at Pontiac Nationals, 2004 Cordova Winner of Quick 16 At Ames 2004 Pontiac Tripower Nats KRE's MR-1 - 1st 5 second Pontiac block ever! "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." "People demand freedom of speech to make up for the freedom of thought which they avoid." – Socrates |
|
#6
03-25-2017, 09:16 PM
|
||||
|
||||
|
Quote:
__________________
My Break Away Squad 1969 Fbird (Base, 350 & Sprint Cvt’s - 400HO & TA Hardtops) 1969 LeMans (2dr & 4dr Hardtop and a Cvt) 1969 LeMans Safari 2 seat Wagon 1969 GTO (2 Cvt, 2 Hardtops & Judge Hardtop) 1969 Catalina (3 Cvt’s & a 2dr hardtop) 1969 Ventura 2 Seat Wagon 1969 Executive 4dr Sedan 1969 Bonnie Cvt 1969 Bonnie 3 Seat Wagon (2 of them) 1969 Bonnie Brougham (4dr Hardtop & Cvt) 1969 Grand Prix SJ (2 of them) 1969 2+2 2dr Hardtop (Canadian model) |
| Reply |
|
|
The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.
Linear Mode
