Frustrated Too! My Engine Still Shuts off after 15 minutes.

[HP_Cuda]

Remember to only change one thing at a time otherwise you will be chasing your tail.

Vapor lock is a condition where a bubble of air gets trapped in your fuel line and prevents fuel pressure. This often happens when the fuel line is near a heat source. Basically the liquid turns to a gas in the line. I don't think this is the problem since you state you have 5 psi with the new fuel pump.

When was the last time you changed your plug wires? As well, what kind of carb do you have and when was the last time it was rebuilt?

[Trevor Y]

The wires are MSD and I ohm'd them out and they are all proper for their lengths.
I do things very detailed, one thing at a time.
Even with 4 of those out, the car would still run home.
I changed out the power valve to a 4.5, cleaned out that bowl and have checked the float levels.
Also cleaned both filters on the carb inlets.
That was one of the first things I did.
If this new MSD-6A digital doesn't do the job, then I'll take Cindys 800 cfm Edelbrock off her 68 Coronet R/T and stick it on.
Then, I'll blow it up....lol
Thanks
Trev

[HP_Cuda]

Actually not a bad idea to take another known good carb and put her on there.

Good luck! 

[Trevor Y]

Ha Ha, I had an idea that even when I get her fixed, I'll pretend I didn't and keep posting like, I changed the right rear tyre and still nothing...., just to keep you guys entertained!!!
lol
Trev

[HP_Cuda]

 

[ChallengerHK]

I was going to suggest that you put your left index finger tip to your nose, hold your right ankle in your right hand and hop around the car three times. Always worked for me.

[msbaugh]

Does it stay at 5psi? If the pressure shoots down it could be vapor lock, but doesn't sound like it. Even less likely if you have a return line. I only say that because it sounds similar to an issue I was having with vapor lock

[Trevor Y]

GREAT SUCCESS EVERYONE! 
After the new Digital MSD-6A install, she ran for 40 minutes straight tonight.
Even included some burnt rubber.
Thanks to all for your help and inspiration!
Now to get the carb tuned properly by the local carb expert, or just buy a new one.
I think there is still room on my mastercard!
Trev

[msbaugh]

  Isn't it so nice when things work?

[HP_Cuda]

Hot dang!

I love the smell of fresh burnt rubber in the morning! 

[Trevor Y]

I am going to change out the carb just so everything is now done and have great confidence in the car.
I took my Girlfriends carb off of her 68 Coronet R/T and stuck in on mine, Wow what a great difference.
This is what I have now:
Holley Street Avenger 670 with vac sec and elect choke.
This has:
Edelbrock Thunder AVS 800 with vac sec and elect chock.

Now, the 800 cfm works on my car, but is it too big, what should I look for. Should I get the same carb as her?
I like hers a lot and just need to adjust the secondary's as there was a slight bog in 2nd and 3rd while rolling about 30 mpg with my 727.
I have some kind of mild cam and headers.
I put on a stock 68 383 manifold with 1" spacer to get clearance.
I have a 727 with 2500 stall they said and 323 8 3/4 posi.

I'll have to start a new thread, but though I would post this here to finish off this replacement thread....lol.

Oh ya boyz, I also mounted my MDS epoxy filler coil on the fender using my washer bottle. It had one mounting hole on it, so it looks ok there.

Thanks
Trev

[HP_Cuda]

Perfect timing!

http://www.cuda-challenger.com/cc/index.php?topic=84870.0

[Chryco Psycho]

I would go to a 770 Avenger or better yet a 750 Proform