HyperSpark CDI box wire routing.

[RealWing]

I'm going to mount my box in the car under the driver's seat on my '69 Cuda. https://www.forabodiesonly.com/mopar...ration.428719/. I can route all the wires through the unused clutch rod hole in the firewall. My question is: Is it OK to run all these wires through the same hole, or do I need to separate some? I'll also run the Holley handheld display through the same hole as well. Thanks, Jim

[a b c]

As long as you use the proper wire protection (gromets & such), your idea will be fine.

[AndyF]

@RealWing: I wouldn't put the CDI box under the driver seat. Up on the firewall behind the glove box is a better location, since the wires can be shorter and they won't be under the carpet.

[Gaz64]

@AndyF: Agree. Wiring can be shorter, easier to work on, easier to fault find, and won't be the first module to get wet. How many manufacturers place modules on the floor?

[RealWing]

Unfortunately, the Cuda has factory A/C and the large unit under the dash takes up all the room on the firewall! I can't see moisture being a problem inside the car, since the unit can be installed under the hood where it can get soaked. The instructions say, just don't install it upside down.

[RealWing]

Wow, lots of wiring to sort out behind the engine! Lots need to be shorter while respecting separation.

[AndyF]

Looks like you're going for a factory resto look. If so, you'll need to modify the factory PCV valve so it's a fixed orifice type. Do not run a factory PCV valve with the Sniper. It can stick open and cause a hung throttle condition. You should be able to take a factory PCV apart, and then run a small tube through it and pot it with RTV.

[RealWing]

Andy, yes it's a factory resto look project. Had not heard about the PCV valve issue. Any guidance on orifice size? Thanks very much for the tip. There doesn't seem to me many Mopar Sniper installs on this site. Jim

[Danny Cabral]

The documents in this post #32 LINK state it's a 0.100" hole.
https://forums.holley.com/showthread...312#post239312 (Related Fixed Orifice PCV Valve Thread)


No need for making your own, or Holley selling it: MicroGard PCV2377 (← 99¢ at O'Reilly Auto Parts)
https://forums.holley.com/showthread...1540#post51540 (See "Fixed Orifice" PCV Valve Part Numbers)
If you need the 90° version, simply reuse your old plastic 90° plastic barb fitting.
Yes, the 90° black plastic hose barb pops off the old PCV & onto the new PCV valve.
https://forums.holley.com/showthread...524#post264524 (Additional PCV Valve Grommet Information)

[AndyF]

@RealWing: I've done a lot of Mopar Sniper installs. The wiring conversion from the ballast resistor over to full 12 volts for both run & start is the big stumbling block. Orifice size with a fixed PCV isn't super critical. Maybe try 0.090" and see how that works.
I'm not so sure that 50 year old alternator is going to work with the Sniper. You might need to convert to a modern alternator if that one won't work with the Sniper.

[RealWing]

Hi Andy. Hope I can use you for a sounding board as I proceed with this Mopar project? I had the same issue of getting a full 12 volts in run & start when I did my 6.1L Hemi Cuda restomod. Solved that by utilizing a start pushbutton hidden in the console ash tray as opposed to using the ignition switch to start the car. Works great.
I wondered about the alternator as well. However, it has the optional higher output alternator. I had it completely restored by Dixie Restorations and it put out a max of 56 amps on the bench test. Will see when I get it running! Jim

[Danny Cabral]

https://forums.holley.com/showthread...790#post104790 (Alternator Information For EFI Applications)

[AndyF]

@RealWing: It isn't the amps, it's the noise. Old alternators can be really noisy since they didn't have to be quiet. Modern alternators are designed to work with modern electronics. That is the crux of the problem with a restomod type of car. You can't just randomly mix and match old parts with new parts since they were not designed to work with each other. I don't think you need to get rid of the alternator now, just be prepared for it to be a problem.

I'm not sure why a pushbutton would work any better than the ignition key. Just wire the start and the run circuits from the key together with the pink wires from the distributor, ignition box and Sniper.

[RealWing]

@AndyF: Thanks for the insight on the alternator. I agree, there's no filtering on the output of the old alternators to suppress the noise from the switching diodes. If you wire run & start together from the ignition switch, you still need a separate start signal to the starter relay.

[AndyF]

@RealWing: The Mopar ignition key has a separate yellow wire that goes to the starter relay. Start & Run off the ignition key can be hooked together to power the Sniper. Look at your schematic to verify if anything else is attached off the start circuit on your car. In 1969 there shouldn't be much if anything on the start circuit. Later models had various seat belt buzzers and stuff like that.