Engine Bucking While In Gear.

Thanks guys...have the timing set at 11° now and is where it idles best and throttle response is better but once its driven for a while temp climbs to about 240-250 with the timing correct could this be a plug issue i was told to get autolite plugs and gap them to .054 right now has ngk g power hot plugs pre gapped but i never checked the pre gap like a fool ....also did a new furl filter last night after i try different plugs i think i might be headed towards injecters for some reason i think its running to lean ignition really only thing left is distributor coil but unsure if that will create these symtoms
 
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Thanks guys...have the timing set at 11° now and is where it idles best and throttle response is better but once its driven for a while temp climbs to about 240-250 with the timing correct could this be a plug issue i was told to get autolite plugs and gap them to .054 right now has ngk g power hot plugs pre gapped but i never checked the pre gap like a fool ....also did a new furl filter last night after i try different plugs i think i might be headed towards injecters for some reason i think its running to lean ignition really only thing left is distributor coil but unsure if that will create these symtoms
 
Also bought a 160° thermostat will that help with a lower opening temp?
Bad idea - the computer is tuned with the engine temp set at 195°.

If you have problems with the engine running too hot, look at the cooling system. Spark plug heat range has nothing to do with engine temps.
Is the radiator full to the marks? No air in the cooling system?
Do you have the radiator overflow filled to the proper mark?
Are you running underdrive pulleys?
Is the inside of the radiator coated with crusty light colored deposits?
Is the plastic air deflector under the radiator present and in good condition?
Are there obstructions to airflow across the radiator? Pine straw, leaves, dead bugs or mud?
 
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Bad idea - the computer is tuned with the engine temp set at 195°.

If you have problems with the engine running too hot, look at the cooling system. Spark plug heat range has nothing to do with engine temps.
Is the radiator full to the marks? No air in the cooling system?
Do you have the radiator overflow filled to the proper mark?
Are you running underdrive pulleys?
Is the inside of the radiator coated with crusty light colored deposits?
Is the plastic air deflector under the radiator present and in good condition?
Are there obstructions to airflow across the radiator? Pine straw, leaves, dead bugs or mud?
 
I will check into that tonight will warm it up to normal temp a take a temp reading across the radiator there isnt anything in front of the radiator all external is clear levels are good so ill check to see if coolant is flowing properly and go over your list and see where the problem is
 
@Frank M. is this car otherwise stock? I know you stated you just picked it up....so is that to say it's always run this way since you owned it? How are you certain that it's overheating? Are you just going by the stock dummy gauge, or have you got a quality temperature gauge to measure your reading?

Any milky substance in you oil? When the car is stone cold, start it to let it idle and check your overflow tank to make sure you aren't seeing bubbles. A bad head gasket will cause the engine temp to climb.
 
@Frank M. is this car otherwise stock? I know you stated you just picked it up....so is that to say it's always run this way since you owned it? How are you certain that it's overheating? Are you just going by the stock dummy gauge, or have you got a quality temperature gauge to measure your reading?

Any milky substance in you oil? When the car is stone cold, start it to let it idle and check your overflow tank to make sure you aren't seeing bubbles. A bad head gasket will cause the engine temp to climb.
Yes appears everything was stock even the fuel filter the distributor had the factory knotch/score doesnt appear like anything had been done other than oil in the past ....and yeah ive been relying on that old gauge 20161020_114643.jpg
 
Its your cam and tune that's causing the issues, not your ignition. Cams that were designed to make horsepower on the big end, don't generally have nice street manners down low. Bucking below 1,500RPM is very common in a small block EFI V8 with a hot cam. You want a cam with at least 112-114 degree's lobe separation to keep the ECU happy on a street car. The further away from this figure, the shorter the shorter the power band seems to get and low speed torque and driveability suffer. My suggestion would be to do your best to find out exactly what cam is in this thing, and start budgeting for one that's more street friendly if you can't.

Also, I wouldn't count on the fact that it's been "tuned" to eliminate that from the list of possibilities. A lot of so called "tuners" will shoot for maximum horsepower on the dyno, but spend very little time on driveability. So while it may technically run well, keeping the A/F ratio's in check across the board and make good numbers on a dyno, that's not to say it's doing you any favors down low.

Welcome to the world of high performance.....where nothing is a straight forward as it seems on paper and everything costs twice as much as you thought it would.

^^this.
Figure out your cam spec's.
Mine (107* installed at 105*) has been tuned beyond belief, sitting still, on the dyno, and on the street hooked to the laptop. Anything steady state below 2000 gets choppy, and try steady state at anything below 1800 and it'll try and throw you through the windsheild... repeatedly. Having said that, it is no big surprise to me as when the cam was designed the cruise speed was engineered to be 2200 or higher.
It idles like a champ, and I can drive through the lower rpms (lightly accelerate) but don't try and steady state it down there... it open it's eyes around 3000, yawns stretches and gets out of bed around 4000 by 4500 it's sitting at the table and from 5000-7200 it's taking care of business.
Now, don't take that to mean it's hollow down low, it'll still boil the drag radials from a roll in 2nd gear, but where it's happiest is up top.
 
Found the issue too my over heat and bucking misfire issue come to find out was a bunch of paper and old filter in the maf screen cleared it out lost misfire and temp was faulty gauge replace with mechanical gauge all is good now found exhaust leag at headers clamp smh fml!!!!
 
Now everything is working if i run her kinda hard she stays in the 210° range in traffic if sitting at idle 230° but cruising down highway at low rpm 60mph drops below 190° is this normal?
 
Now everything is working if i run her kinda hard she stays in the 210° range in traffic if sitting at idle 230° but cruising down highway at low rpm 60mph drops below 190° is this normal?

The car should sit idling or in traffic without getting up in the above 200° point.
 
Didn't go back to look but describe your cooling system. Important things like lower hose not collapsing when raising rpms which by your description is not a problem, rising temp at idle and/or slow speeds points to flow, either air or coolant. Clean radiator fins, cooling fan operation and coolant flow need to be addressed. Also there is a plastic piece that bolts below the radiator vertically but that usually effects air flow at speed.
Puke tank in place and working properly, correct cap pressure is important.
A stock or even a mildly moded setup does not require a fancy aluminum radiator and/or electric fans, they are good additions but most times will mask the real problem, some of this I have learned from personal experience but mostly from the 'experts' on here.