[wcarrothers]

Hello..

1967, 396 motor, quadrajet carb, 4spd, points IGN.

This is my first post (and only just got the car) so hopefully not jumping the gun asking questions. But in anycase curious of what I should look into having this problem.

Leaving the line. getting on the gas hard car has power then bogs then power then bogs off and on. Seems to not bog at higher speeds at WOT (so talking RPM's above 3500 seems ok)..

Has a quadra jet carb so been tinkering with the secondary spring. adjusting that does not seem to effect the problem. So I'm starting to think about the ignition. (not knowing if the points are adjusted correctly although I'm also thinking of upgrading that part)..

Need to check where the timing is set. (wondering what is typical for a 396) But car drives fine other wise so thinking the timing is set ok in anycase.

Still have to check the plugs.. And installed a O2 sensor so I could watch. Seems to peg to the rich side before it stumbles when this goes on (but again probably need to observe a little more)

Seems to have plenty of power and pep outside of this bog area..

Hopefully will not have to take to deep a dive to get things a little better.

b.

 

[ranvette]

You do not say what it has for a cam? Timing typical for a slightly cammed up motor would be set at 14 to 18 btdc.Total timing would be 38 btdc for best power.Its hard to tell from what your saying but! First thing i would do is wet the ign wires down with water.Than put the engine under load and see if a secondary ign skip shows up.Than check timing/Fuel pressure/float setting/Fuel line size should be 3/8 line/Check condition of fuel line and fuel filter.What are the temps running where you are? Vapor lock can happen in high temp areas.Also what is the points dwell set at?These are just some checks that need to be made !

 

[lg1969]

check the Plastic diaphram housing. It could be defective.

 

[77 cruiser]

Choke pull off could be bad & letting the air valve open too fast. Unhook the vac. hose push the diaphram in & put your finger over the hose & see if it holds vacuum.

 

[wcarrothers]

Only just got the car and of course seller was a bit foggy on details. But the motor looked to be a pretty fresh and well done rebuild. Have some reciepts and build info on that which the builder wrote up (weight of different parts inside as it went thought the balance process etc.)

I do have the cam numbers and will post but would say it's a mild street cam.

Anyway other then what ever is causing this issue the car drives quite well. (was a 600+ mile ride home..

In looking around the car yesterday I noticed a small black box in the front driverside of the eng bay. One of those 103 voltage regulators. The plug didn't look like it was completely plugged in. Have not looked at the alternator to see if it's updated (thus not needing an external regulator) and have not driven the car since plugging it in (watch it will no longer run or something..hehe) But in any case don't recall the voltage gage in the car doing any strange or spike over 13-14v..)

Anywho hopefully will get this one issue sorted out. Basicly was looking for a list of suggestions on what to look at. I'm 36 years old. And basicly except for 2 - 77 mustangs I've not really had a carb car (first car was a 78 malibu excpet it has a 86 corvet 350 with the TPI stuffed in it)

Done a lot of mods to cars with fuel injection. But alot of tuning there is just getting the pressure right. Guessing as the hobby gets in the hands of younger people going to have more people asking perhaps bad questions.

Anyway the way this car runs off WOT and slightly off WOT I'm pretty sure I'll have a good runner once this is sorted..

b.

 

[wcarrothers]

The fuel lines are basicly new off the shelf tank to motor, tank is new as well. Look to be of correct diameter and nicely layed out. I would want to say I don't have a delivery problem to the carb but don't have a pressure gage on it yet..
Checking the timing has been on my list although here in MI it's been raining the last couple days. I'll have to put the timing light in the car so I don't forget..

Here is a quick pic of the motor. Hopefully will agree it's to pretty on the out side not to run correctly. Actually was one of the reasons I went for this particular SS. can't tell you how many of them I looked at with hidious looking motors, rusted and just nasty cond. car leaks from the munci and a little from the pinion seal but no oil leaks from the motor
http://users.ameritech.net/watchdogflyball/Motor.jpg
http://users.ameritech.net/watchdogflyball/SSChevelle.JPG


b.