timing query
8 posts
• Page 1 of 1
everything runs fine. over last 5 years I've never had pinking , even when i've not bothered with additives . Bear in mind I've a stock pre-unleaded head used to running on 4star! So maybe you can forgive my thoughts that timing might be a little retarded...so i thought i'd check .....
According to the book, standard cam early +2 with Webers is 14deg btdc at 2500rpm.
I have ~ 19deg btdc at 2500, ~10deg btdc at idle.
I'd be happy to have anyone's interpretation and comments/.observations pls.
Rich
According to the book, standard cam early +2 with Webers is 14deg btdc at 2500rpm.
I have ~ 19deg btdc at 2500, ~10deg btdc at idle.
I'd be happy to have anyone's interpretation and comments/.observations pls.
Rich
-
RichC - Fourth Gear
- Posts: 741
- Joined: 28 Apr 2009
Reading the workshop manual with regards ignition timing is a problem as it has a few errors.
The 2500rpm quoted in the manual as crankshaft rpm is actually distributor rpm but the 14 degrees is actually crankshaft degrees as quoted. The 14 degrees is centrifugal advance and needs to have the static advance of around 10 -12 degrees added.
This gives you maximum advance of 24 to 26 crank degrees at engine 5000 rpm
The 19 degrees you measured at 2500 engine rpm is about right and well within the tolerances on the measurment and distributor.
cheers
Rohan
The 2500rpm quoted in the manual as crankshaft rpm is actually distributor rpm but the 14 degrees is actually crankshaft degrees as quoted. The 14 degrees is centrifugal advance and needs to have the static advance of around 10 -12 degrees added.
This gives you maximum advance of 24 to 26 crank degrees at engine 5000 rpm
The 19 degrees you measured at 2500 engine rpm is about right and well within the tolerances on the measurment and distributor.
cheers
Rohan
-
rgh0 - Coveted Fifth Gear
- Posts: 8425
- Joined: 22 Sep 2003
8 posts
• Page 1 of 1
Total Online:
Users browsing this forum: No registered users and 30 guests