What's the deal with crappy throttle response?

[Ben B.]

My '78 350 runs okay I suppose, considering I have no idea of the mileage and whether or not it's original and stuff.

No knocks, rattles, or weird noises.

It's not a powerhouse either, but it's not bad.


One thing that is concerning to me however, is extremely crappy throttle response. Now since I've owned the truck I haven't changed anything to the motor or tuned it up, so I dunno what it might be. Suggestions are welcome, of course.

When it's cold, the response is there, I can tap the pedal and it'll tach up, but once it warms, I'll have to literally hold the pedal down for it to reach higher rpms and it takes so long to get there.

I want some Vroom vroom, not vroooooooom [pause] vrooooooooooooom.

Help me out buddies.

 

[y5mgisi]

I would first check your ignition timing.

 

[vortec]

timing is a good place to start.

is your choke working right?

are the fuel lines mounted in such a way that you may be experiencing a near vapor lock situation?

 

[Ben B.]

I'm a mechanical newb fellas. I need to start reading up on this stuff.

I know my poor qjet has a bit of a gas leak though.

 

[Cowboy_80]

Timing is a good thing to check, but my first action would be a tune up. plugs, wires, cap & rotor, coil, air filter, fuel filter. After you do all of that and there's still a slow response, adjust timing.

 

[Bent77]

Make sure the timing is correct, but don't just add timing at will. Remember that it can ping if you over time it.

After doing all of these things first, if it doesn't run better, you might need to rebuild and degum the carb. It is possible that the accelerator pump is not operating to full capacity.

 

[bp71k5]

You might also check all your vaccuum hoses. Leaks in any of those will cause all sorts of havoc. Although a bad one would probably make it not start at all.

 

[Bent77]

If you use a can of carb cleaner with the red straw, the engine will suck it into a vac leak if you have one. It will change rpm when it does. Works best if you don't hose the whole engine...

 

[blazin_blazer]

on our dirt track cars...we take the advance springs out and twist to full advance and tack cross bar fully advanced w/mig...then set timing between 32-34 btdc...no lag when stomp skinny pedal...prolly only good 4 trail only tho