dcorley

car is an 88 5.0

EFI going to MSD6al, Blaster coil, etc

Just curious as to why current dizzy wouldn't work.. I believe I need one from an 85 302 because they have steel gears, correct? Thanks

my77stang

that only matters if your changing to a flat tappet cam. its the cam gear that meshes with the dizzy that is the issue. as long as your msd will tie into the dizzy your using, you should be fine.

FivePointOhh

well according to his title i assume you mean you are EFI going to carb. why you need a new dizzy for that is because carb works off vac advance where as EFI has the ignition control module instead of the vac advance to control timing. or maybe thats not what your asking and the answer above work

dcorley

ah thats right...i don't have the vacuum advance hanging off the side of mine.

2 kwik

[sm=laughat.gif]

FivePointOhh

are you laughing at 77 stang or me?

my77stang

yeah im confused? i was pretty sure they make harnesses so you can plug a late model EFI dizzy directly into the MSD ignition box...... if thats correct, then as long as he is leaving a roller cam in there he wouldnt need to change the dizzy.

am i missing something? my knowledge of all the EFI generation of components isnt as great as my knowledge of the older stuff, but i thought i had that right

ddeaton66

Timing is controlled by the eec via a spark table that references rpm & load. Theoretically if those sensors were left intact and the computer installed it should continue to control the timing while you run the carb for fuel. I am unsure whether TPS is involved in the computer determining load....if it is then you will not have that input and the computer would go to "limp mode" and base timing. With another dizzy (vac or centrifugal advance) you won't need the computer's input for timing.

I think!! It's been a long day. LOL

ddeaton66

Yep, ya need that tps signal for the eec to determine timing advance. Else-wise you'll be running at base timing and performance will not be optimum to say the least

Personally I prefer mechanical advance......

dcorley

thanks for clearing things up. rebuilt 85 gt distributor is only $50 at autozone so no big deal.