Surprisingly bad performance - like really really bad.

[rhorvick]

Just bought a 73 k-10 (350, TH400) and in 2WD (yes, I'm sure) I can't get it over 65 on flats and 55 going up hill (thankfully in North Dakota hills are a rarity).

This just seems really wrong.  I don't have a tach but it does not sound pegged out (the engine actually sounds really good to my untrained ear) and there are no strange noises when I get to the max speed.  Transmission fluid is filled (and a nice red).

It just seems like the floor is a little too close to the pedal - or there is too much free play.

Could my throttle linkage have slipped or stretched over time causing that to be the case?  If so is there a good way to test that?  Maybe pull the air filter and look at the throttle plate and see if it doesn't go verticle with the gas pedal floored?  Or shouldn't it do that?

If it isn't that my next thought was to check:

1) spark problems (are all 8 firing)
2) compression
3) dwell and timing

Am I missing another obvious thing to check?

Does anyone know what the stock rear end gearing was for a 73 k-10 (or how to find out)?  I doubt it is rear end gearing but I guess that is another possibility.

This isn't like I want to get another 30 HP or do some major performance tweaking.  I just want to drive up hill!

Oh - and I am getting into third gear.  It's not a matter of being stuck in second.  It drops into third at about 45mph.

Thanks.

Robert.

[stepside454]

if you think its in your gas pedal, have someone hold it to the floor, while you see if you can open the carb up more...to see if the pedal is opening it all the way

[rhorvick]

Throttle cable is not even connected to the throttle plate - it's just hanging about half open (which is probably also why I'm idling fast).  I don't know how to fix this but I know how to read my repair manuals - so I'm half way there

Thanks.

Robert.

[Corso 1]

Rob-

  It sounds as though someone may have swapped the carb and not set it up correctly. As you just purchased this, maybe that is why they determined that they needed to sell it. In other words, you may have gotten a great deal. Especially when you correct the problem and really see what you've got. Good luck and keep us posted.

P.S. Still perform the check that was suggested earlier. Believe it or not, the cable VS Carb opening adjustment is often overlooked. Just wasted power potential!!

Corso

[shadecrack]

just one other thing to think about, I had a 74 nova that the exhaust pipe had somehow skrunk inside , It would haul butt to about 40 -45 mph and that was it.. I had already scheduled dual exhaust to be put on, that cured it.

I talked to my shop teacher and he had heard of this happening though rare..  It drove me nuts trying to figure out what was wrong for about 2 weeks... not saying it is the problem but if the exhaust is restricted, it will hinder performance. still can't believe the difference.
good luck.