Ideas to make truck tow better

[downslope]

I still have my '73 K20 Cheyenne I bought new. We've grown old together. I'm sure it will outlast me.

I still have my '73 C30 bought new. 350 4-barrel, 4.1 rear. 350's were good, 292 six was good, 307's not so much.

 

[94BULLITT]

This thread is really jumping around.

Problem Statement - Truck has low power at takeoff.

1st question - Has it always been this way, or is this a new problem?

The issue has to be related to only a few things. A gas engine needs air, fuel, spark, compression, and exhaust.

- Air - Is it getting enough air? Is air cleaner clean/new? No restrictions in the air path? Fresh air intake?

- fuel - Is it getting enough fuel? Too much fuel? Is the fuel pump pumping? Does it have a fresh fuel filter and new clean fuel? What do the spark plugs look like? Dark, light, ashen?

- Spark - What do the plugs look like? I have had varied performance with different plugs... What about the wires, rotor, cap? Has the timing been checked? Are the wires held in the loom properly? Had a Ford with a 400 that had to have the plug wires held in the holder along the valve cover properly, or else they would short to each other...

- Compression - engines are just a big compressor. What does the compression look like? After adding a bit of oil to cylinders(rings)? What does leak-down look like?

- Exhaust - What does the exhaust look like? My experience with a clogged Cat is no power above idle. It would be a dog at speed but should start off ok.

It's gotta be one of those four. Air, fuel, and spark are pretty easy to check. Compression is not too hard with right gauges.

Good advice in the above post. ^^^^

I would also check and make sure the truck and trailer brakes are not hanging. Jack one wheel up at a time and have someone hit the brake while you try to turn the wheel then get the to release the pedal and the wheel should immediately turn easy. Also did you figure out what trans you have? Does the truck have a "grandma low" gear in it?

 

[handirifle]

One thing came to mind, and I hope I am remembering correctly. But IIRC the 350 engines were notoriously hard on cams, and when the cam lobes wear out, that engine will be gutless, assuming you had adequate power when it was new. That's not a big engine for a 3500.

Before I would spend the money on rebuilds, regearing or anything I would know the value of the truck, and decide if it was worth putting the money into. A re-gear can be $1000+ for 4WD (don't remember if yours is 4x2 or 4x4) and if the engines worn out, it won't help a lot.

As suggested, I would run a compression test, for ring/valve wear and make sure it's getting proper fuel and spark. In 1st gear that truck (even with a 350) ought to start off a lot better than that. I know the 70's version of the 350 put out around 200hp, pretty pathetic, not sure what yours is rated for.

You can turn that engine into a powerhouse with things like stroker kits etc, but the truck might not be worth the engine. It's all about $$$

 

[handirifle]

After reading bullits post, check the CAT REAL close. I used to work for a shop in the early 80's and he ran leaded gas (it was still available then) through all his trucks. It was a lot cheaper. Then all of a sudden the CAT's would clog and that truck would barely move it's self. Pull the CAT off and drive around. It will be LOUD, and see what the power is like. You will know right away if it's was clogged.

Also in the late 60's GM used to have a double wall exhaust pipe from the Y pipe to the muffler. If the pipes were hot, and you drove through a deep rain puddle, the outside pipe stayed the same, but the inside pipes collapsed. Results were HUGE losses of power. I know Cadillacs did this and some Old's. Not sure if they even double walled then, but just a thought. The new pipe restored the original power.