So I was fiddling around with the car yesterday and have ran into something I’ve never experienced before. First off is what I was fiddling with;

1977 440 stock bottom end and 452 heads. 6a msd, torker 2, quick fuel 750( 72 front 78 rear jets) stock 727(I think)

-I set the timing from what looked like 27-30 intial to 15-17, I need to get a timing tape to be precise.

- carb from 74 front 82 rear to 72 and 78.

-Switched pcv and brake vacuum lines around so pcv runs off carb

-got about a quarter of a can of seafoam through manifold vacuum line.

Now, the reason I did this is that it was a slug even though it had no detonation with all that timing. Figured if I dialed it back I had a better baseline to mess with. After my guesstimate on timing and a rejet it ran way better. Took it out to the highway after it warmed up and hammered it. Definitely acting more like a big block but.... it was a quick blip but it acted like I still was in the throttle for a second or two after I let off. Powered right through the brakes.

-Checked return springs. Good, actually too much resistance
-No binding. Won’t doing anything it’s not supposed without load on it(in neutral)
- I’m stumped, car is still very new to me so I’m slowly working through it.

Any guesses?

Dry/kinked throttle cable.

Yeah binding cable perhaps.. weak spring or i have had the kickdown arm rub the bottom of a drop base air cleaner too.

Did it again without air cleaner. Spent 15 minutes in neutral revving without binding. Has 3 springs on it, it’s got a solid return.

I’ll order a new throttle cable just in case. I’m still stumped and now I have to fix the paint from hitting a welding cart before I got it shut down while putting it gear. Yes, I’m a dumba** for doing it in the shop.



Maybe I’ll order a cable kick down too. It has a rod style setup now. I didn’t get it to bind but maybe

Might want to check out the motor mounts to be sure the motor isn't torqueing over putting things in a bind.

just keep your factory "kick down" rod and your money. that isn't your problem.
i am NOT a fan of that [gm based] lokar junk.

Unhook the pcv line from the carb, plug the port.
Try it again.

Power brakes? Could be a leaky diaphragm.

If it has really weak springs in the distributor, it might just have so much timing it’s keeping the rpm up.

Have you tried driving it without the air cleaner ?

Also make sure there is a bit of slack in the accelerator cable when idling warm off choke

Speaking of chokes, any chance the fast idle cam is activating??

Can't add much... but don't use too much return spring tension. You'll wear out the throttle shaft bores.

Fast68,
Unhook the pcv line from the carb, plug the port.
Try it again.
ok, maybe too much vacuum?

Power brakes? Could be a leaky diaphragm.
yes, I’ll check

If it has really weak springs in the distributor, it might just have so much timing it’s keeping the rpm up.
I’ll see what’s in it

TJP,
Have you tried driving it without the air cleaner ?
yes, no change.

Also make sure there is a bit of slack in the accelerator cable when idling warm off choke
there is

Speaking of chokes, any chance the fast idle cam is activating??
I’ll check

Stumpy,
Might want to check out the motor mounts to be sure the motor isn't torqueing over putting things in a bind.
should have bound while still in park though, right?