any Accel Gen VII wizards here?
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From: Inverness FL
St. Jude Donor '07
any Accel Gen VII wizards here?
i'm on the C1/C2 forum but it was suggested that i also post my EFI question here. i would appreciate it if you would take the time to read the following thread link and offer advice.
http://forums.corvetteforum.com/show....php?t=2049207
Bill
http://forums.corvetteforum.com/show....php?t=2049207
Bill
Melting Slicks
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From: St. Charles Mo
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Bill, after reading the thread, I wonder if you are focusing your attention in the wrong place. What's going on with the IAC during all this?? If you want to send me a copy of your cal file, I will take a look at it. If so, I will PM my e-mail. In the mean time, try to get a handle on IAC positioning with your data logger.
Bullshark
Bullshark
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From: Inverness FL
St. Jude Donor '07
does anyone know how the Accel VE table correlates with injector size?
will a smaller 24# injector flow less fuel than a 30# injector while still using the same 30# VE table values, or will the ECM try to compensate for the smaller injector in order to bring the flow back up to the 30# rate?
Bill
will a smaller 24# injector flow less fuel than a 30# injector while still using the same 30# VE table values, or will the ECM try to compensate for the smaller injector in order to bring the flow back up to the 30# rate?
Bill
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Ron
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From: Inverness FL
St. Jude Donor '07
still having hot start problems...
Bill
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From: Campbell CA
By the way, there is an Accel tech guy that watches the Chevy Talk EFI forum. You may want to post the question there. Do you have a check valve on your fuel pump outlet? I installed the one from Aeromotive, it made my hot starts quicker. It doesn't hold pressure well enough for cold starts.
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From: Inverness FL
St. Jude Donor '07
By the way, there is an Accel tech guy that watches the Chevy Talk EFI forum. You may want to post the question there. Do you have a check valve on your fuel pump outlet? I installed the one from Aeromotive, it made my hot starts quicker. It doesn't hold pressure well enough for cold starts.
some seem to think too much timing; but i've lowered the cranking timing to 1 degree and, although it starts a bit easier, i'm still having problems
thanks..
Bill
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From: St. Charles Mo
CI 5 & 8 Veteran
Bill, how old is your Accel Dual Sync distributor? I was over at my friends Performance shop working on setting up a couple of Twin Turbo BB motors last week for a 42 foot offshore runabout. 
We were experiencing some anomalies and after a witch hunt we were able to find that the new Accel Dual Sync distributors were different. Seems they had a very narrow cam sync window in the dual shutter wheel that triggers the pickups on the circuit board. This resulted in the blue light (cam sync) turning off almost simultaneous with the #1 cylinder crank (red light) trigger. We put in an older model dizzy which had the wider cam window and everything cleared up. My friend was going to call Accel and find out what the story was, but I have not talked to him to get an update. If you are experiencing almost simultaneous blue/red light transition during setup you might want to verify which one you have by removing the circuit board, or maybe looking down the shaft under the circuit board and check the cam window width.
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I will let you know what we find out and why the difference.
Bullshark
We were experiencing some anomalies and after a witch hunt we were able to find that the new Accel Dual Sync distributors were different. Seems they had a very narrow cam sync window in the dual shutter wheel that triggers the pickups on the circuit board. This resulted in the blue light (cam sync) turning off almost simultaneous with the #1 cylinder crank (red light) trigger. We put in an older model dizzy which had the wider cam window and everything cleared up. My friend was going to call Accel and find out what the story was, but I have not talked to him to get an update. If you are experiencing almost simultaneous blue/red light transition during setup you might want to verify which one you have by removing the circuit board, or maybe looking down the shaft under the circuit board and check the cam window width.I will let you know what we find out and why the difference.
Bullshark
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From: Inverness FL
St. Jude Donor '07
Bill, how old is your Accel Dual Sync distributor? I was over at my friends Performance shop working on setting up a couple of Twin Turbo BB motors last week for a 42 foot offshore runabout. We were experiencing some anomalies and after a witch hunt we were able to find that the new Accel Dual Sync distributors were different. Seems they had a very narrow cam sync window in the dual shutter wheel that triggers the pickups on the circuit board. This resulted in the blue light (cam sync) turning off almost simultaneous with the #1 cylinder crank (red light) trigger. We put in an older model dizzy which had the wider cam window and everything cleared up. My friend was going to call Accel and find out what the story was, but I have not talked to him to get an update. If you are experiencing almost simultaneous blue/red light transition during setup you might want to verify which one you have by removing the circuit board, or maybe looking down the shaft under the circuit board and check the cam window width.
I will let you know what we find out and why the difference.
Bullshark
We were experiencing some anomalies and after a witch hunt we were able to find that the new Accel Dual Sync distributors were different. Seems they had a very narrow cam sync window in the dual shutter wheel that triggers the pickups on the circuit board. This resulted in the blue light (cam sync) turning off almost simultaneous with the #1 cylinder crank (red light) trigger. We put in an older model dizzy which had the wider cam window and everything cleared up. My friend was going to call Accel and find out what the story was, but I have not talked to him to get an update. If you are experiencing almost simultaneous blue/red light transition during setup you might want to verify which one you have by removing the circuit board, or maybe looking down the shaft under the circuit board and check the cam window width.I will let you know what we find out and why the difference.
Bullshark
i can rarely get Accel support to answer my questions, so i'm having to find 'outside' help who've 'been there, done that'....
here's a pic of the shutter wheel in my distributor
Bill
Last edited by wmf62; Jul 8, 2008 at 04:15 AM.
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From: Inverness FL
St. Jude Donor '07
this is the second distributor i've had, the first one had the sensors come off the bottom of the board and leave me stranded....
i now have a 3rd one as a spare.....
Bill
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From: Inverness FL
St. Jude Donor '07
the only way i can see to judge is by comparing the circuit board holddown cam to the wheel and, unfortunately, i don't see the difference....
i do know that when Accel sent me a new one, they said that there was a newer shutter wheel in it. the one i have in the car now is the one i got through Summit as i didn't want to wait for Accel to figure out what they were going to do about replacing the one that came apart. the only obvious difference i saw between the one i got through Summit and the other 2 is that the pigtail to the circuit board for the Summit one comes out on the firewall side through a keyhole shaped slot (which i prefer) and the 2 from Accel come out from the front side through a grommeted u-shaped slot. all are Accel distributors, i just don't know what their production dates are as there seems to be no numbers/codes on them anywhere.
Bill
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From: St. Charles Mo
CI 5 & 8 Veteran
Bill, the two Accel distributors that have the slotted U shaped grommet are the newer configuration. They would have the narrow cam sync window. That window is on the inner shutter circle, with only the one slot.
The older version ( probably the one you got from Summit) has the cheap o-ring grommet and would have a larger window in that inner shutter circle. Not sure what all this means but, I would think it should have some effect on setup?? I have been trying to get through to Accel to ask this question with no success.
Bob
P.S. Just got off the phone and from what Accel told my friend, there should be no issue with the window slot difference. Computer takes care of the sync. I will have to think about this a little???
The older version ( probably the one you got from Summit) has the cheap o-ring grommet and would have a larger window in that inner shutter circle. Not sure what all this means but, I would think it should have some effect on setup?? I have been trying to get through to Accel to ask this question with no success.
Bob
P.S. Just got off the phone and from what Accel told my friend, there should be no issue with the window slot difference. Computer takes care of the sync. I will have to think about this a little???
Last edited by Bullshark; Jul 8, 2008 at 01:57 PM.
Thread Starter
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From: Inverness FL
St. Jude Donor '07
Bill, the two Accel distributors that have the slotted U shaped grommet are the newer configuration. They would have the narrow cam sync window. That window is on the inner shutter circle, with only the one slot.
The older version ( probably the one you got from Summit) has the cheap o-ring grommet and would have a larger window in that inner shutter circle. Not sure what all this means but, I would think it should have some effect on setup?? I have been trying to get through to Accel to ask this question with no success.
Bob
P.S. Just got off the phone and from what Accel told my friend, there should be no issue with the window slot difference. Computer takes care of the sync. I will have to think about this a little???
The older version ( probably the one you got from Summit) has the cheap o-ring grommet and would have a larger window in that inner shutter circle. Not sure what all this means but, I would think it should have some effect on setup?? I have been trying to get through to Accel to ask this question with no success.
Bob
P.S. Just got off the phone and from what Accel told my friend, there should be no issue with the window slot difference. Computer takes care of the sync. I will have to think about this a little???
NOW i see where you're talking about... as i see it (pun intended...), it's the edge of the standing portion that triggers the sensor, not the slot; so if the 'edge' is in the same place in relationship to the outer ring 'edge', then should be no difference.. BUT, i can't tell in my picture where the other end of the slot is or it's relationship to the outer ring...
Last edited by wmf62; Jul 8, 2008 at 02:32 PM.
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From: Campbell CA
Bill,
I still think this is a distributor issue and not fuel. The symptoms you describe are exactly what I experienced when I was using the MSD distributor. Changing to the Dual Sync fixed it completely for me. You might want to double check the phasing of the distributor. I thought the instructions from Accel were a bit sketchy. It took me a couple of tries to get it right. I also had to flip the rotor 180* to get the tach drive to line up properly. Try posting to the Chevy Talk forum. There's an Accel tech on the EFI forum. Although I suspect he might be on vacation this week.
p.s. I sent you my ecm file.
Bob
I still think this is a distributor issue and not fuel. The symptoms you describe are exactly what I experienced when I was using the MSD distributor. Changing to the Dual Sync fixed it completely for me. You might want to double check the phasing of the distributor. I thought the instructions from Accel were a bit sketchy. It took me a couple of tries to get it right. I also had to flip the rotor 180* to get the tach drive to line up properly. Try posting to the Chevy Talk forum. There's an Accel tech on the EFI forum. Although I suspect he might be on vacation this week.
p.s. I sent you my ecm file.
Bob
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From: Inverness FL
St. Jude Donor '07
Bill,
I still think this is a distributor issue and not fuel. The symptoms you describe are exactly what I experienced when I was using the MSD distributor. Changing to the Dual Sync fixed it completely for me. You might want to double check the phasing of the distributor. I thought the instructions from Accel were a bit sketchy. It took me a couple of tries to get it right. I also had to flip the rotor 180* to get the tach drive to line up properly. Try posting to the Chevy Talk forum. There's an Accel tech on the EFI forum. Although I suspect he might be on vacation this week.
Bob
I still think this is a distributor issue and not fuel. The symptoms you describe are exactly what I experienced when I was using the MSD distributor. Changing to the Dual Sync fixed it completely for me. You might want to double check the phasing of the distributor. I thought the instructions from Accel were a bit sketchy. It took me a couple of tries to get it right. I also had to flip the rotor 180* to get the tach drive to line up properly. Try posting to the Chevy Talk forum. There's an Accel tech on the EFI forum. Although I suspect he might be on vacation this week.
Bob
my replacement distributor was set up & synced in accordance with the instructions and went in exactly the same way/place as the first one, so if i set up the second one wrong, then the first one was also wrong (always a possibility, but i've checked the timing several times by forcing the timing to 20 & 30 and also verifying it 'unforced' against the dashboard; i don't know what else there is to check).
i looked at the Chevy Talk forum and there are an incredible number of postings on there (probably as many in a month as we have in the C1/C2 forum in many months). i haven't had much luck with getting any help directly from Accel, so i'm not sure what a forum Accel guy would do; besides, you can't post for free like you can here (call me cheap, but i've already put a ton of $$$ into this...), and i didn't see any threads similar to mine problem on there.
Bill