View Full Version : Well this phase of Daughter's Coronet did not pan out........ Broken!

10-16-2015, 11:50 PM
To make a long story short, took my daughter's car to the track first time this year. Planned on taking it out in April, but found the cam was wiped. Put a hydraulic roller in it and been dealing with it since. Engine is noisey and not sure where the noise is coming from.

Motor is destined for the GTX and planning on going back to stock with the Coronet. So I figured put some runs on it and if it breaks it breaks. Not sure what I'm gonna do to the motor before it goes into the GTX at this point.

Before my daughter got to the track I put 2 runs on it. First run went 13.300 at 101.75 mph. I was pleased with it (4000 lb street car with AC).

Second run slows to 14.097 at 95 mph. Car broke, but I don't think its the motor. I am leaning towards a tranny failure.

Unstinkinbelievable! The tranny was new with the motor last year and both have about 300 street miles and 30 runs.

I guess this phase was cursed and time to cut my losses. Car is now going back to stock a little sooner than I expected.

10-17-2015, 03:17 PM
What were the 60 ft times with both runs?

10-17-2015, 09:57 PM
Not good 1.954 on the good run and 1.950 on the second run. Second run started to fall off right after the 60 ft.

10-17-2015, 11:09 PM
Did it feel like it was falling on itself? Just wondering if it's a fuel issue and not a trans issue...

10-18-2015, 09:38 AM
Did it feel like it was falling on itself? Just wondering if it's a fuel issue and not a trans issue...

Its definitely a mechanical failure. Coming down the return road every time it hit a bump or pot hole it would clunk (when it unloaded). I was in denial but it is there and getting worse. When I was taking it off the trailer and I put it in reverse with the brake on, it was shuddering pretty bad. Pulling it into the garage the clunking got worse. My tranny guy thinks it might be a broken planetary gear. There is a chance its in the engine or converter - at this point not 100% sure where the issue is. The clunking part does seem to be coming from the tranny area.

Just before the second run, it made a weird noise and slight jerking when I put it in drive heading for the burnout box. I didn't think much of it at the time, but in retrospect I think that was the beginning of the failure.

I do need to move the car from the front garage to the rear garage - that is where I do major work. Will be interesting to see how the car behaves during the move and if I will make any additional headway in finding the failure.

10-18-2015, 10:25 AM
If it's not clunking when in park/neutral I'd rule out the engine and possibly convertor. (The fact it did it over bumps also kinda negates it I think).

Keep us updated on it. Hopefully it's nothing major.

10-18-2015, 02:23 PM
Motor and tranny are coming out. Gonna rebuild the original 383 and put it in. In fact the original tranny is at the tranny shop being rebuilt right now.

Tranny is coming apart. My buddy charges only $150 for labor so its a no brainer. Might beef it up some for the GTX. It does have a steel drum in it now and good clutches.