New engine gremlins - frustrating

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OK, that is all good and makes more sense. MRL is saying what I was thinking: the mechanic's info was not right. The last numbers make sense. (Being a hand's-on kinda guy, I know I would be re-checking myself! Which is what MRL is saying.... timing advance is so critical to engine operation that it HAS to be confirmed as right.)

So has this changed the engine behavior, or is it too cold to check?

And BTW, I don't throw things anymore (too expensive) but I sure do yell a lot....LOL

FWIW, on the TC and cam: The latest, higher stall TC numbers you are now getting make more sense with the cam. But I would not consider that combo to be a cruising combo..... low end RPM's are too high. If you are really going to cruise and not drag race, then I'd be thinking a cam change, not a TC change. It does not mean that you won't be happy with an engine that has a high low end operating RPM if you up the TC stall speed....I am just pointing out the application versus cam/TC choice.

Now back to your regularly scheduled program... which is fixing the stumble.
 
Timing appears to fix the bog issue. Carb can still be tweaked a little. Throttle return looks a little odd and return to idle speed not always crisp, please see pic. I drove it for 30 min. Running 17* initial with 36* total with the vacuum advance permanently disconnected and capped.

Thanks everyone it's been a long 3-6 months.

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Thank you again everyone.

If I unbolt the front 2 drivers side intake bolts to mount a throttle return spring bracket, will this cause any potential issues with the gasket? I would torque them back to spec with a torque wrench.
 
Just my opinion but reconnect the vacuum advance. It does not hurt anything and will vastly improve part throttle cruising activities.
On the intake- no prob. You change nothing unboltimg and revolting. I'd also look really close at the lockdown linkage you have vs a factory one. I think you have a wrong spring.
 
TRWRacing said:
If I unbolt the front 2 drivers side intake bolts to mount a throttle return spring bracket, will this cause any potential issues with the gasket? I would torque them back to spec with a torque wrench.
Click to expand...
Should be OK; do it all at one time so that there is no chance that the cooling passages up in the front of the heads and intake will have any chance to seep anywhere.
 
Please bare with me here. With 17* initial and 36* total timing, then I will need to re-curve the distributor via the mechanical springs and adjust the vacuum pot for 35-36* total at 3000 rpms to match the current configuration.

The kickdown linkage is how it was when I got the car with it's 340, but I will revisit some old pics that I have of the carb before the work was done. I look at other linkage pics via Google and I see what you mean.

Ok on the intake bolts. I will be doing that in the spring.
 
No - you don't recurve anything. You take the vacuum pod and connect it to the ported vacuum nipple on the carb. Then, you may need to adjust the vacuum can preload if it surges or pops on you. The vacuum advance is not figured in total timing as you have been doing it. It is on top of the totals of initial and certrifugal. So you keep the 36° total, and simply plug in the vacuum dashpot. You may also need to research that dashpot adjustment with the manufacturer of your distributor. Factory stuff uses an 11/32 allen wrench inserted into the nipple of the distributor's vacuum dashpot.

You have a throttle return problem - the spring for your kickdown rod is not a factory spring - it looks like it might be rubbing on the linkage and that might be enough to make it not want to smoothly return to base idle speed.
 
Good read here! Am I missing something though with the.throttle springs? Shouldnt they be.going towards the front of the engine?
 
Ok I got the spring fingered out...at first I didn't see the other end of the spring connected to the kick down.
Imo I would put a return spring on it before it hits the road again.
4spdragtop said:
Good read here! Am I missing something though with the.throttle springs? Shouldnt they be.going towards the front of the engine?
Click to expand...
 
I will look at it tomorrow but he has a 2nd spring on the throttle lever on the bottom picture that looks to counter balance for a throttle return spring. I am putting it away for winter tomorrow after just filling it up with fuel and stabil.

In the spring, then install a throttle return bracket and spring.

It is my understanding through research that this the the 3 piece kickdown and need that corresponding spring, instead of the one piece.
 
yabut
As you can see, the springs pull to the rear.....and so does the throttle cable.This puts a lot of force on that little tiny rod that the butterflies attach to, inviting premature wear on the throttle body.Eventually those blades will not park properly and then you get idle-issues.
Sending the return spring to the front, eases the pain on the throttle body.
The KD spring can be very lightly anchored with just enough spring to park it. In driving, you will never notice if it does not park absolutely to the front. The only purpose that spring serves is to reduce line pressure to make the shift softer at light throttle applications.
 
I will correct that. I will get a SBM correct throttle return spring bracket. This is how the installer had it.
 
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