12-1 crank trigger setup
- Thread starter BEATAV8
- Start date
Steve V's Automotive
Member
Good stuff here. I will go back and look at my car and apply this. Don gave me different instructions as well. I forgot---LOL
We may still need some tweaking. On Thursday the car was absolutely perfect, then saturday we did a few more things. New fuel pressure regulator, fuel pressure sensor, and got the tachometer wired to tach out. Went for a drive and she was all of a sudden showing a super nasty lean spot at/after tip in. Idle was not right as well. Very strange because this car was about as perfect as it could get in the drivability area. I was snooping around trying to figure out “what’d we change that screwed it up” and as I was leaving I finally thought “it’s on the wrong phase” which would explain why it was running crappy, but not why it would incorrectly select phase after correctly selecting phase many times before. When I get back to it I’ll verify the phase and if that’s it I’ll try advancing the cam sensor some more. It may need another tooth between cam and “the gap”?
Steve V's Automotive
Member
I have been dealing with the tach issue for a few years the 18-2 wheel I use requires that mod if you want factory tach to work. I have also been using fuel pressure correction for quite sometime too.
I have been driving the 12-1 car around this past holiday weekend still running great.
Confirmed we do NOT have a phase selection issue today. Changing phase made her much worse.
Looking close at the data I think I see the culprit. The MAP signal looks very lazy. It's not jumping up with the TPS. I think the MAP hose must've gotten squished or kinked somewhere under the dash or behind the glove box when we were running new wires back there. Gotta take a look.
Looking close at the data I think I see the culprit. The MAP signal looks very lazy. It's not jumping up with the TPS. I think the MAP hose must've gotten squished or kinked somewhere under the dash or behind the glove box when we were running new wires back there. Gotta take a look.
that will cause really odd stuff like you are seeing. I know of one case where the vacuum/map source was moved to after the HVAC checkvalve. That one really ran wierd.
Bob
Update: We're planning to advance the pulley 1 bolt hole (60 degrees) in order to optimize the tooth timing. This will change the tooth angle from 75 degrees to 15 degrees. Car has been perfectly fine so far as-is, but this tweak should make it even more robust for detecting the missing tooth quickly and accurately.
I think my artwork above is backwards, my yellow arrow should point the other way... lol
It's been starting nicely as-is. My missing tooth time is around 1.7x the previous tooth during cranking. If I move it I think I can get it well over 2x.
It's at 75 degrees now, so advancing it 1 bolt hole should put it at 15 degrees. Retarding it would be 135.
But I was thinking advance it, move tooth #1 60 degrees closer to TDC#6. I guess either way I go I should end up next to a shorty.
The ATI version of the pulley is indexed differently than the BHJ version. We just did one of the ATI's and ended up with tooth times way over 2x for the missing tooth. I liked that a lot so I decided to revisit this one to optimize it.
It's been starting nicely as-is. My missing tooth time is around 1.7x the previous tooth during cranking. If I move it I think I can get it well over 2x.
It's at 75 degrees now, so advancing it 1 bolt hole should put it at 15 degrees. Retarding it would be 135.
But I was thinking advance it, move tooth #1 60 degrees closer to TDC#6. I guess either way I go I should end up next to a shorty.
The ATI version of the pulley is indexed differently than the BHJ version. We just did one of the ATI's and ended up with tooth times way over 2x for the missing tooth. I liked that a lot so I decided to revisit this one to optimize it.