hot starting when hot help 91 mustang

Hi everyone I have a 91 mustang hot start problem when running after 20 minutes the battery is new but it’s not a big one? I would like a bigger one like a ?group 65 battery with more cranking amps .

it’s been a very big headache for me any help or tips to try I would greatly appreciate it . The car has the battery relocated New 2 gauge wire to factory locations up front . then from the solenoid I did a 4 gauge wire to starter. With a new a 14gauge? Signal wire.

This what’s all New new on it ? Starter distributor coil plugs wires
Map sensor
headers that are warped. Long tube
Tin diy heat Shield. Heat warped the starter wires too
I added 2 ground wires in the back
New alternator 3G set up
Tps sensor set
Timing at 10


I did the volunteer drop down test and got a
With coil off got 9.63 volts off the battery

But it seems like it starts gd cold no problem so its ? My wires to the back of car 2 gauge then to 4 gauge to the starter and alternator?
It’s something electrical?

But I’m at not sure what test to do ? Next or what video to watch for more help ? Was even thinking? A relay ?
Please help me or give ideas and information on what I should do .thanks guys and girls..

General karthief said:

This is a hard one because there are a lot of variables. Condition of cables, battery condition, ground locations.
Best I could advise would be a voltage drop test starting at the battery, just a thought, next time the hot start problems occur feel the cables starting at the battery up to the starter, this may give you a hint.

Click to expand...

Thanks I will try it