I'm curious what sort of maximum ignition advance any of you with similar setups are running.
I have about 25k miles on a 2.7 RS spec motor, PMO's, Elgin mod-S cams, 9.2:1 CR. The car is raced a few times a year, sees ambient temps from 40° to 105°, and usually runs on a blend of 91 street and 95 or 100 (when it's hot) race gas. Plugs are NGK 6's. Motor runs strongly, plugs are beautiful, distributor is set to 34° max advance.
jhtaylor
santa barbara
74 911 coupe. 2.7 redone by Competition Engineering; ported to 36mm, shuffle-pinned, boat-tailed, Elgin mod-S cams, J&E 9.5's, PMO's.
73 Targa (much beloved, sold and off to a fine new home in San Francisco)
James,
2.7 RS + 120/104 WebCams, 019 spec MFI, 9.5 CP, lots of intake head work, stock '73 S points distributor....
Perfect plugs, no rattle even in summer @ just a hair over 36 degrees.
Hope this helps
Chuck Miller
Creative Advisor/Message Board Moderator - Early 911S Registry #109
R Gruppe #88
TYP901 #62
'73S cpe #1099 - Matched # 2.7/9.5 RS spec rebuild
'67 Malibu 327 spt cpe - Period 350 Rebuild
’98 Chevy S-10 – Utility
’15 GTI – Commuter
Thanks Chuck, there might be 2° in my future! I assume your motor has more than a few hundred miles on it?
jhtaylor
santa barbara
74 911 coupe. 2.7 redone by Competition Engineering; ported to 36mm, shuffle-pinned, boat-tailed, Elgin mod-S cams, J&E 9.5's, PMO's.
73 Targa (much beloved, sold and off to a fine new home in San Francisco)
The '2003 2.7 rebuild has well over 60K on it......I assume your motor has more than a few hundred miles on it?
Same car and motor that was behind you when you showed me the way around Buttonwillow.......... Thanks again BTW....
Chuck Miller
Creative Advisor/Message Board Moderator - Early 911S Registry #109
R Gruppe #88
TYP901 #62
'73S cpe #1099 - Matched # 2.7/9.5 RS spec rebuild
'67 Malibu 327 spt cpe - Period 350 Rebuild
’98 Chevy S-10 – Utility
’15 GTI – Commuter
I'm at 34 with a full factory spec 2.7 RS MFI.
David
'73 S Targa #0830 2.7 MFI rebuilt to RS specs
Someone questioned me about why my vacuum advance was not being used on my distributor and I did not have an answer. I thought it was an emissions thing that the hot rodders did away with, but this guy mentioned something about vacuum advance improving throttle response.
Can anyone shed light on the issue for me?
1971 911S, 2.7RS spec MFI engine, suspension mods, lightened
Early 911S Registry Member #425
Max, I don't think your car ever had a vacuum advance.With few exceptions among the early cars, the vacuum retarded the timing rather than advancing it. It was an emissions/economy thing. Not sure why a bit less advance would help throttle response. While you are here, what is your timing? Jim
jhtaylor
santa barbara
74 911 coupe. 2.7 redone by Competition Engineering; ported to 36mm, shuffle-pinned, boat-tailed, Elgin mod-S cams, J&E 9.5's, PMO's.
73 Targa (much beloved, sold and off to a fine new home in San Francisco)
Sorry, I don't have that information.
The motor is built on a 7R case from 1974. The distributor is ???? It has a vacuum canister on it. The port is just open to ambient. What you say reinforces what I thought at the time.
1971 911S, 2.7RS spec MFI engine, suspension mods, lightened
Early 911S Registry Member #425
Mine's factory 8.5:1 on webers. 36° total advance on a re-graphed distributor (for 98RON)...
John Forcier
EarlyS #1987
1968 911 Race Car "Grun Hilda"
1969 S/T interpretation "Blau Healer"
Restoration Saga
Max, your dizzy has vac retard, which is not necessary.
Aaron Burnham
Burnham Performance
1071 Avenida Acaso ste D.
Camarillo, Ca. 93012
805-240-6931
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