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Taylorman
02-27-2003, 07:27 PM
What should I set the initial timing at on my 455. Its set at 8 now. I have my MSD distributor setup to advance 25 degrees and be fully advanced at 3000rpm. Last weekend i put a timing light on it at 3000 rpms and above and it would only advance to 26. It should be at 33 (8 initial + 25 centrifugal). Has anyone else had this problem?
jim@pj
02-27-2003, 08:37 PM
Taylorman... You really can't be sure how well your mechanical advance is working until you put the distributor on a machine. Your dial back light will get it close but it is just not as informative. I prefer to run 10 - 12 degrees initial for better response which would put your total at 35 to 37 degrees. If you have the high compression piston (390 horse stock) don't go any higher than 37. Jim www.performancejet.com (http://www.performancejet.com)
GlastronGuy
02-28-2003, 08:04 AM
I am running at 11 initial, 32 total set up on a machine. I have heard that running up to 36 is OK. I am running 10/1 compression so I try to run it on the safe side. I also mix a little race gas in it. Again, to be on the safe side.
jim@pj
02-28-2003, 09:56 AM
Glastron. Sounds good. I prefer to run around 35 total especially if you have a cam with alot of over lap. Run a lot of fuel to the motor with the proper pressure and you will be oK. If you get nervous check your plugs they will tell you what is going on. JIM
GlastronGuy
02-28-2003, 01:20 PM
My cam is:
.512/.523, 230°/236° @ .050, 108° Lobe
Fuel pressure is 7 PSI and on a carb shops recommendation I am running 2 fuels pumps. An electric at the tank (in bow) and a mechanical at the motor. Carb is a Q-jet with PackAJet logs.
jim@pj
02-28-2003, 07:49 PM
glastron... You shouldn't have a problem at 35 degrees. Good luck Jim
GlastronGuy
03-01-2003, 10:50 AM
Thanks.
Taylorman
03-01-2003, 11:32 AM
Who has a machine to check a distributor? I checked the bushing I have in it and its the second to smallest which should allow 25 degrees of advance.
GlastronGuy
03-01-2003, 11:52 AM
Taylorman:
Who has a machine to check a distributor? I checked the bushing I have in it and its the second to smallest which should allow 25 degrees of advance. You'll probably have to find a shop. The guy that set up my carb has one but he's in Yuba City, CA. That won't help you.
MikeF
03-01-2003, 05:15 PM
Taylorman, There is a place here in Ca called www.ignitioneering.com (http://www.ignitioneering.com) that can do it, (pretty much rebuild it too) but it's a little far!? :rolleyes: