Poor mans MSD dizzy for 2.8

[kimcrwbr1]

I took my duraspark dizzy and disconnected the vacuum advance and timed it at 20 degrees btdc, adjusted the idle air for the highest vacuum pressure. I hauled three loads of compost without skipping a beat. I am going to try running it without the vacuum advance for a full tank and see if it affects mpg any she seems to run just fine. Plenty of power and it seems to take less pressure on the foot feed at all speeds we will see.

 

[Twister]

I wish you lived closer to me so you could tune mine for me

 

[kimcrwbr1]

The only hard part is getting to the dizzy bolt. Turn your idle air screws out 3 1/2 turns and get the engine up to temp choke fully open. loosen the dizzy bolt just enough it is hard to turn the dizzy pull the vacuum line and plug it. Time it at 20 dbtdc lock it down with the idle at around 750 rpm. Adjust the idle air screws for either the highest rpm or vacuum pressure mine are out about 4 turns then set the idle speed I like 750 rpm. Then you can adjust the choke just leave the vacuum advance disconnected. I call it my poor mans MSD because it dont have the vacuum advance. I am still gonna play with it like that maybe advance or retard it some my goal is finding the proper total advance for the upper end for fuel economy and the throttle responce off the line seems better also.

 

[alwaysFlOoReD]

How many degrees in the mechanical?

Richard

 

[kimcrwbr1]

I`m not sure that is why I want to play with it the damper marks dont go that high. I was thinking on scratching in some marks using the scale on there to get close. I know the 302 likes it around 38 degrees btdc total advance and with the msd ignition you time it according to engine ping. Advance it until it pings at medium speeds 35 to 40 mph when you put your foot down and then retard it until it dont ping. The thing with my 2.8 you cant hear the ping in the cab driving down the road. I`m kinna shooting from the hip here the vacuum adds 10 degrees that is why I am starting at 20 degrees that way it is all mechanical/centrifugal advance I dont think it was reaching total advance with the vacuum in play on the upper end. I had a vacuum guage in the cab driving down the road and it allways ran better going down hill with high vacuum but when you got your foot into it I am sure the timing was retarding when you want it advanced at high speeds. The high performance MSD ignition dizzys dont have the vacuum advance besides my 2.8 idles a hell of alot better at 20 dbtdc I am just taking the vacuum advance out of the equation. I think it gives a better balance between fuel delivery and timing.

 

[Big Jim M]

Oh yeah!!!

I`m not sure that is why I want to play with it the damper marks dont go that high. I was thinking on scratching in some marks using the scale on there to get close. I know the 302 likes it around 38 degrees btdc total advance and with the msd ignition you time it according to engine ping. Advance it until it pings at medium speeds 35 to 40 mph when you put your foot down and then retard it until it dont ping. The thing with my 2.8 you cant hear the ping in the cab driving down the road. I`m kinna shooting from the hip here the vacuum adds 10 degrees that is why I am starting at 20 degrees that way it is all mechanical/centrifugal advance I dont think it was reaching total advance with the vacuum in play on the upper end. I had a vacuum guage in the cab driving down the road and it allways ran better going down hill with high vacuum but when you got your foot into it I am sure the timing was retarding when you want it advanced at high speeds. The high performance MSD ignition dizzys dont have the vacuum advance besides my 2.8 idles a hell of alot better at 20 dbtdc I am just taking the vacuum advance out of the equation. I think it gives a better balance between fuel delivery and timing.

Dude!! Put the damn vac advance back on there! It IS PINGING! You simply cannot hear it!
How guys can think they have reinvented the gasoline engine in their driveway I will never understand..
If it would do ANYTHING better Ford would have left the vac advance off of there themselves..
The timing of the engine depends on the rate at which the fuel burns. 20* advance off idle is waaay too much! You may simply grenade the engine and it will be all over!
The way it works is a well thought out method of getting the timing where it SHOULD be at various RPM! You have defeated the intent of the engineers and fatal results can be in your future.
Some racing engines have mechanical advance only... Them engines NEVER go from stoplight to stoplight. They run at high rpm all day long and are single purpose engines. The vac advance serves to make our lil trucks driveable at all rpm..
PUT IT BACK!
Big JIm
PS You other guys that are chiming in... Forget about this dude! He is traveling the WRONG trail!

 

[enginepaul]

Gotta agree with Big Jim.
If your engine is advancing too much off the line (which is what I suspect is the reason for getting rid of the vac advance) then try a vacuum delay fitting. I used one once from a Pinto. (not on my 2.8 because I'm in California) The vac delay slows down the rate of advance but still allows full vacuum. A web search should turn up more info, including a picture, of the vacuum delay. They are found connected in the hose from the vac source to the distributor advance canister.
Sorry to say that the easiest way isn't always the best way.

 

[kimcrwbr1]

Actually your not getting it it is my engine and my experiment. If it burns up then I can do a 5.0 conversion or rebuild a 2.8 either way there talking about doing californica emissions here and the ranger will have to be scrapped because it will never pass smog tests and I will never let a hack mechanic touch it just to get the waiver. If I burn it up the prick is 28 years old and still kicking it. I couldnt tell you how many times it ran out of coolant and a few times with no oil pressure. It yanks my boat just fine but I am still looking for a 87-88 2.9 2wd to replace it something dependable cheap and can pass smog tests easy enough. First gen RBV all the way