Fuel Pressure Measuring?

[doubleyellow]

OK, so after 100 hours of troubleshooting it looks like it is the ORANGE BOX.

I waited to change it out because it only had a few hundred miles on it, so I couldn’t believe it was the box. But thanks to XCuda and 540Cuda, they pointed out I put my box on the engine (to hide it for OEM look), but you guys are correct, the heat and vibration messed it up.

I bought another crappy box (it says Delphi on it?) and hooked it up. Finally no power loss upon acceleration.

Not sure what to do. For now I have to keep the box on the engine to get to some car events. After that I either have to get another Mopar Orange Box and hide it somewhere besides the engine, or get a good quality mechanical distributor and just deal with the points.

Even though this has been a nightmare, I learned:
- much more about tuning carbs
- much more about fuel pumps/pressure
- how playing with timing affects performance
- how the ignition affects performance
- how crappy all the aftermarket crap is
- how I should listen more to the FEBO experts !!

Still have to run it some more, and tune it up, but in the meantime thanks for all the help. Sure I’ll need more help soon.

 

[Xcudame]

See the ECU from Mancini below. I know they will stand behind their products. Get the standoff plate too and mount it on the firewall like the 72-74 E-Bodies. Won't be hidden, but won't give you problems either!

MRE - Orange Ignition Control Unit

MRE - ECU Mounting Bracket Kit

If you really want to hide the ECU, I suggest either in the glove box (although it's cardboard) or somewhere hidden under the dash. Make sure the ECU body has a good ground!

 

[540HemiCuda]

If you don't want to drill holes to mount the ECU on the fire wall, just use some double sided tape like they use for emblems. That stuff is strong. Heat may be an issue with it, but would be worth a try with the mounting bracket. The mounting bracket is not a requirement, it just might offer more surface to mount it with the tape. Otherwise, you don't need it.

The Mopar orange boxes have been crap for many years. I have thrown many away. If Mancini's is the Mopar one, I would pass. If they have their own version, that may be a different story. I would ask them.

Personally, for an ECU I like the old Crane Hi-6. Bulletproof and have a built in rev limiter with dials, no 'pills' like MSD. You see them on Marketplace now and then. They are by far, the best ECU I have ever used. They last and last and last. Unlike the MSD stuff. And they play well with your stock distributor.

Here is one version (Hi-6N; NASCAR with the window), and just happens to be the same one I have on my Cuda now. (I just bought it cause it was cheap.) There are several versions and most will work for you: Pardon Our Interruption...

 

[Chryco Psycho]

Rev-N-Ator is good also

 

[Xcudame]

I posted the link to Mancini's "in house" ECU. They sale Mopar Orange Boxes as well.

On my 70 Challenger, I have an MSD 6A bought in the 90s when they were still made in the USA and not China! Hi-6 and Rev-N-Ator are good too!

 

[Bret Schneider]

"I waited to change it out because it only had a few hundred miles on it, so I couldn’t believe it was the box. But thanks to XCuda and 540Cuda, they pointed out I put my box on the engine (to hide it for OEM look), but you guys are correct, the heat and vibration messed it up"

So maybe not the part's fault after all?
If the box wasn't mounted correctly chances are it wasn't able to dissipate the heat via the firewall as it was designed to do leading to premature failure. That along with the additional vibration from the engine that it also wasn't designed for wasn't doing the electronic module any favors...

 

[Xcudame]

@Bret Schneider, good point, the ECU was always isolated from vibration and the factory bracket was obviously to help with any heat transfer. But I have seen the newer Chinese ECUs have the resin that encapsulates the electronics melt out sitting on the self! Of course it gets pretty dang out here June in Arizona! I still believe the factory engineers had the right idea mounting the ECUs high on the firewall with the bracket to help dissipate heat! The factory original electronic ignition was one of the best out there!!

 

[Bret Schneider]

Exactly right. I know engineers take a lot of grief on these forums and some rightly deserved, but in this case the module was placed where it was for a reason. Ignition modules generate a lot of heat that needs a path out of the part. The biggest part of the Chrysler ECU is the metal heat sink, not the electronics. Eventually that heat sink is going to get heat saturated if it's not properly attached to something, the firewall in this case, that it can pass the heat to. The firewall is large enough to absorb that heat along with the heat generated by the voltage regulator and ballast resistor.

 

[Xcudame]

Thanks @Bret Schneider, the cat is out of the bag. I am an engineer. And back in the 50s, 60s and 70s Chrysler had some of the best engineers out there (think Ramchargers)!
They tried hard to build the most bullet proof cars out there fighting the bean counters all the way!

 

[MILOJ]

When I worked in a mopar garage we had a fuel volume tool, hoses bottle and pinch shut off and had to time it as the bottle filled to see if it was up to specs

 

[Ronbo73]

Yes it’s on the engine because I’m going for OEM look and was not going to drill holes on the firewall.

I do have another box I could try. BTW recommendations on best quality box currently on the market?

Eventually I could hide it under the battery tray? Or is that also a lousy spot due to dirt and moisture?

Is there a quality all-in-one distributor that doesn’t use an external box?

I did put a mechanical points distributor on and it still had the power loss (that distributor is a crappy asian one so could also be bad), but let me try the electronic box change out first.

I will have a look at the pump rod

Finally…..I’m still running my original vapor separator…..could the separator or the fuel return line cause power loss? I’ll bypass the separator today…. easy enough to try

Thanks for all the input so far !

I switched from the Mopar electronic ignition to the Summit brand, ready to run distributor. It fit under my 6 brrl air cleaner and has vacuum advance if needed. Knock on wood, I have not had any problems.
Using the RTR distributor allowed me to clean up the firewall a bit and less wires.

 

[Xcudame]

I think even the crappy Chinese ones aren't horrible. You just need to keep a couple spares in the glove box and make sure it's grounded very well!

 

[Challenger RTA]

standoff plate too and mount it on the firewall like the 72-74 E-Bodies

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[Ricks72Chlgr440]

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Man my heart skips a beat when I see a thermoquad!!!