Topic: 1978 Trans Am Tuning Issues

[Fahad_Qatar]

Hi Marx thanks for responding. setting the idle and timing while in drive is written on the emission sticker which is in front of the radiator. See this thread it has a pic of the decal  http://transamcountry.com/community/index.php?topic=54226.0

However, it does not state how to set total timing.

[marx3]

oh yeah, I see that. Says so on the sticker in my ´78 also. I wonder why the factory suggested this method. I guess it was so that no one would experience stalling when trans was put in gear, due to the idle being set too low

It should not be necesary to set neither the timing or the idle in gear.
You need a dial back timing gun to check and set the total timing. Usually the timing for a 400 or 403 has such a high initial timing setting, that you can't set it much higher without getting in trouble when hot starting...

[side0ut]

I have finally gotten to work on the car since the weather has improved.  I found that my ignition coil was bad and causing the engine to run badly and stall after warming up.  I replace it and now don't have that problem any more.   Still had the problem with stalling/stumbling from a stop with engine surging while cruising.  My friend finally finished my original Q-jet carburetor.   I put it on and for the first time in 8 years, my car ran much better.  No more stumbling/stalling and no more surging when cruising.  Power is a little bit down but I can live with that.  My friend said he put in bigger jets so I might have to re-time the car to meet the different carb setup.  I only have one bug left to try and fix and the car will be running great. 

I have something wrong with the cooling system.  When the engine get fully warmed up, there is a inconsistent pulsating that makes a horrible tapping sound and makes the upper radiator hose jump.  I took a video of it.  It looks like an animal trying to break out of an anaconda.  I tried to run the engine with the radiator cap off thinking that it was air in the system and trying to get the air out.  It still does it.  I tried to remove the thermostat thinking that it was something with that.  Still did it.  Not sure what to do next.  Never had a car do this.  When it does this, the engine runs rough and you can feel it in the brake when at a stop and in drive.  What do you guys think? 

[Fahad_Qatar]

mmm thats weird. Might be a water pump related issue?  Does the cooleant level decrease? assuming that you don't have a leaky radiator like mine 

[side0ut]

It does not seem to be loosing any water and I put a new water pump on it when I re-did the top end.  Also, it does not get hot.  Stays about 180-200 degrees.  Have not had a chance to mess with it again.