Hello all.. I recently went thru my '74 Louisville 800 ten-wheeler (dump) it has under 30k miles and is in overall great shape. My problem is that it runs up to about 35-40mph and max's out. It runs smoothly, starts nicely (although a bit cold-blooded in the NH winter) and uses no fluids. power churns thru a 5&3 overdrive duplex. A complete tune-up was completed last fall and after fighting with the original governed Holly carb for several weeks it was replaced by a comparable non-govened Edelbrock. I am aware of the risks of over-revving this motor and I do not exceed 3800 rpm's.

My problem is that it runs up to 35mph or so and seems to just level out... and this is empty. I must believe that this low-mileage 391 has the power to move this truck better than this...or should. I am curious about the distributor. I read references to the 'governed distributors' in these trucks.. I am now wondering if I needed to make any adjustments there.

Thanks in advance for any ideas...

 

I believe there are governors on the distributor as well.

Recent discussions:

https://www.ford-trucks.com/forums/1...-do-a-way.html

Fuel pressure may be an issue, as per a post in your other thread in large trucks. Fuel pump and filter would be suspects.

Does it just stop revving, or do you get cutting out, backfire etc?

 

Thanks for the reply.. I wasn't sure which area to post to. NO backfiring or sputtering. It runs really well - smooth idle, smooth revving, and runs as you'd like it to right up to the point where it simply seems to 'level out' which is around 35mph I'm going to try it again paying close attention to the corresponding RPM's.. maybe that will lend a clue. Although I do not know the actual fuel pressure The filter was replaced as part of the tune-up.

 

Thanks for the reply.. I wasn't sure which area to post to. NO backfiring or sputtering. It runs really well - smooth idle, smooth revving, and runs as you'd like it to right up to the point where it simply seems to 'level out' which is around 35mph I'm going to try it again paying close attention to the corresponding RPM's.. maybe that will lend a clue. Although I do not know the actual fuel pressure The filter was replaced as part of the tune-up.
I just went to the link containing the dist. discussion and I think for the minimal investment a pertronix ignition is a good idea.. I need to find that bushing they refer to as well. Thank You for your feedback!