View Full Version : 403 timing advance
henry203
08-28-2004, 09:53 AM
What is the most timing advance I can put on a stock 403 without burning the valves? thanks!
henry203
08-28-2004, 09:53 AM
What is the most timing advance I can put on a stock 403 without burning the valves? thanks!
Time it for 35 degrees total timing with the vacuum disconected.Then hook up the vacuum .if it is to much then you need to limit the vacuum advance. All the mechanical should be in by 3000 RPM. You need a dial back timing light and a harmonic balancer mark that you KNOW is on TDC when it is on TDC on the marker per motor indicator.
I run 12 initial, 35 total @ 2800 RPM without the vacuum advance . Vacuum advance to about 10 degrees to have 45 total cruising.
You will NOT be able to do this with the stock distributor. Rocky Rotella did mine (see the High Performance Pontiac issue a few months back). Rocky redid mine after Performance Distributors could not get it right......
henry203
08-28-2004, 10:22 AM
what is the most advance I can put onto the stock distributor and still get some performance. I dont want to buy any performance things yet as I am debating wether to fix up the 403 or go with a rocket 350. It will probably depend on the condition of the 403 block once its taken down.
NONE with the stocker. You need to run on a sun distributer machine and set it to the specs. The 403 is known to ping and the only thing you can do is run more initial, but stock inital is 18...way too much. The specs I gave you are DEAD NUTS on what you want in a 403. The 403 was a smog motor. It will run like a bat out of hell when tuned and running 9:5;1 compression.
henry203
08-28-2004, 08:55 PM
What did you do to get your motor to 9.5 comp? that was the number I was shooting for.
My plans were maybe .03 over, flat top pistons, #5 heads with big block valves. Mild cam, edelbrock performer w/o EGR roller rockers, high volume oil pump, stock carb, and do some fine tuning.
want about 300~350 hp. I do want to keep the car a weekend/daily driven ride, but I do want it to be FAST. A 3.23 rear is gonna be installed and the tranny I have already has a stage 2 B&M shift kit.
tribute
08-29-2004, 06:12 AM
Maciej,
Check out FCRperformance.com. They have a 400hp kit for the 403 that is supposed to work with the stock heads and still be streetable with pump gas. If you are really serious about your 403 check out realoldspower.com. Lots of good info and if you do a search on the 403 you will find lots of buildup examples and if none of those are what you are looking for; just ask.
I am using #4 heads. The heads were done by FCR performance. The owner is a 403 specialist and makes them scream.
Bandit79403Dave
09-11-2004, 08:20 AM
I agree with what the above say http://forums.performanceyears.com/groupee_common/emoticons/icon_wink.gif Give Terry at FCR a call...he won't steer you wrong...time is tight right now, because we are trying to get our EMC motor finished, but afterward he would be happy to help you out!!! Give him a call soon, but be sure you got some time to talk http://forums.performanceyears.com/groupee_common/emoticons/icon_biggrin.gif