Originally posted by B KING: I have my shift timer set at 3.00, I have a peak rpm reading around 7,000 rpm with the variances I listed in my last post. It's over or under, but mainly under.
I know you use time & rpm. With my data, looks like I need to do something different. Like using rpm, what do you all think?
Consider purchasing this model directly from Digital Delay. It programs in both RPM and Time. When you order directly from DD you’re getting the latest and greatest off the shelf.
Originally posted by B KING: Using a Holley Hall Effect distributor.
When shifting on RPM using a distributor trigger, the shift point accuracy will only be as good as what the distributor output provides. Any play in the cam/ distributor gear or cam walk will affect the shift accuracy. I’ve seen rpm swings of over 400 rpm in some DA I’ve looked at that had worn distributor gears. One can easily distinguish a distributor trigger vs a crank trigger when viewing the RPM channel in a DA. This pic is of a new Holley dual sync. If one can use a crank trigger the shift on rpm becomes much more accurate.
April 13, 2026, 10:26 AM
B KING
M & M,
It looks like the way I'm set-up with the distributor, that the time-based shift timer is the way to go.
I considered switching to a crank trigger but that opens a can of worms with the supercharger pulley alignment. The alignment is critical with the ribbed belt that I'm using. I had a heck of a time setting mine up & out of pure luck got it set-up; it was out of the norm how I accomplished it, dumb luck. Not something I would want to do again & would have to happen if I added a crank trigger.
I've been doing some other research with the help of AI. AI did recommend doing the time & rpm method of shifting, but no mention of the crank trigger. I take AI with a grain of salt, but it makes a person think. I'm considering the DD 1068, even with the distributor set-up. It will have to wait till my son can help with the install. Wiring confuses the shyt out of me.
Thanks for your time, M & M!
2BKING
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3100 lbs. Pump Gas 436
April 13, 2026, 10:40 AM
wideopen231
quote:
Originally posted by B KING: M & M,
It looks like the way I'm set-up with the distributor, that the time-based shift timer is the way to go.
I considered switching to a crank trigger but that opens a can of worms with the supercharger pulley alignment. The alignment is critical with the ribbed belt that I'm using. I had a heck of a time setting mine up & out of pure luck got it set-up; it was out of the norm how I accomplished it, dumb luck. Not something I would want to do again & would have to happen if I added a crank trigger.
I've been doing some other research with the help of AI. AI did recommend doing the time & rpm method of shifting, but no mention of the crank trigger. I take AI with a grain of salt, but it makes a person think. I'm considering the DD 1068, even with the distributor set-up. It will have to wait till my son can help with the install. Wiring confuses the shyt out of me.
Thanks for your time, M & M!
2BKING
Would require cpl spacers if usiung crank trigger. One for blower and one for idler. Same thickness as crank trigger, I just made one for a guy that had same issue, Yes ribbed belt need damn near perfect alignment.
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April 13, 2026, 10:45 AM
markemark
quote:
Originally posted by B KING:It looks like the way I'm set-up with the distributor, that the time-based shift timer is the way to go.
What ignition box (model) is firing the coil?
April 13, 2026, 11:26 AM
B KING
quote:
Originally posted by markemark:
quote:
Originally posted by B KING:It looks like the way I'm set-up with the distributor, that the time-based shift timer is the way to go.
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3100 lbs. Pump Gas 436
April 13, 2026, 11:54 AM
markemark
^^^^^^ I’m not familiar with Sniper EFI HyperSpark Distributor kits installation (much less Terminator X) and have no knowledge if/ how a crank trigger can be made to work with this system (no wiring diagrams). Going to a Holley EFI forum would have the answers to this.
April 13, 2026, 01:23 PM
B KING
Pretty sure I can configure the ECU for a crank trigger & might be able to use it to shift on RPM also.
I'm in no hurry & my son is chomping at the bit to change things over. I'm not overly concerned about it but I'm always looking to make the set-up more efficient. It works good as is, but we are never satisfied. This simple plug & play system works very well for what's! Mid 8s & mid 5s is no slouch, on a 9" or 10" tire. I have more room in the tune to go quicker & faster. Don't really want or need to go quicker but want to go faster. The MPH difference in the 1/4 is a distinct advantage, need to work on the 1/8th mile MPH.
The important thing is it wins rounds/races with its average driver!
2BKING
This message has been edited. Last edited by: B KING,
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3100 lbs. Pump Gas 436
April 13, 2026, 09:25 PM
markemark
If going crank trigger for EFI consider using 12-1 wheel and method. More accurate than 4 magnet especially when using retards at higher rpm’s. You’ll see these on some boost engines.
Originally posted by Tom396: Dear G*d. How am I supposed to keep all this stuff straight as I am hitting the shifter? Take care. Tom Worthington
Do you feel better Tom? If you don't like how we race, don't read about it. I can still do old school, like last year racing a Stock Eliminator wagon; I'm sure other members could do the same.
Glad you're a purist, keep up the great work & allowing our style of racing to live in your head!
2BKING
This message has been edited. Last edited by: B KING,
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3100 lbs. Pump Gas 436
April 13, 2026, 09:56 PM
B KING
quote:
Originally posted by markemark: If going crank trigger for EFI consider using 12-1 wheel and method. More accurate than 4 magnet especially when using retards at higher rpm’s. You’ll see these on some boost engines.
My son is all over this shyt, me debating if it's really worth it. Plus, it gives me a headache thinking will this really help my racing program. I don't use half of my ECU capabilities as it's now. I have always been behind/lacking what the hitters or the best use & I'm sure if I did; I would still be average but without headaches!
If you were nearby, I'd pay you to take care of all this shyt.
2BKING
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3100 lbs. Pump Gas 436
April 13, 2026, 11:08 PM
markemark
quote:
Originally posted by B KING:My son is all over this shyt, me debating if it's really worth it. Plus, it gives me a headache thinking will this really help my racing program. I don't use half of my ECU capabilities as it's now. I have always been behind/lacking what the hitters or the best use & I'm sure if I did; I would still be average but without headaches!If you were nearby, I'd pay you to take care of all this shyt.
The accuracy of crank vs distributor for rpm shift activation is considerable when I review DA. Then if going crank trigger for EFI why not choose the more accurate method for same money. I believe this upgrade is worth the expense.
I do as little as possible with my car (never work on others cars) and only attend to what needs work. Needless to say my car needs much work right now. The engine in the car is starting its 8th season and the rebuilt replacement engine short block is in a plastic bag for the past five years and needs the top end installed. I hope to have this completed and switched out by July latest.
April 14, 2026, 12:12 AM
B KING
quote:
Originally posted by markemark: The accuracy of crank vs distributor for rpm shift activation is considerable when I review DA. Then if going crank trigger for EFI why not choose the more accurate method for same money. I believe this upgrade is worth the expense.
It's not about the cost! I'm not tech savvy on all this advancement. I'm surprised I went with EFI.
2BKING
1980 Camaro Taking the Best Working Small Tire Shyt Box & making it Greater Than Before! 3100 lbs. Pump Gas 436
Take care. Tom Worthington 