First 89Formula

Hi all,

I think I posted some time last year about my sons 89 formula with newer ZZ4 eng in it but has original TPI setup on it and we did some timing and such to it and also changed the trans fluid,filter and solenoid in it well nephew did the work since was at place he keeps his drag cars and got lifts there he read up that solenoid in the 700r4 usually go bad how come wanted to change it, see below what going on with car.

We got car out of storage today and I got to drive it back to my house wow was it fun and quick little car 100 mph got there quickly LOL first time my son let me drive it too LOL he lives about 30miles away so brought car to my house because still issues with car and since I drove it now I see what son was talking about. When slowing down with break on at a stop light at times seems eng would surge and car would jump forward a little like trans is shifting down still? When do take off from light car does jump pretty good. When cruising at any speed eng would surge but then be smooth for a good while. Also when cruising would punch it and I say few sec car would then take of and it does sound good he does of edlebrock headers on it with cutouts. Is tuff trying to explain what car is doing.
So can it be bad trans?
Vacuum leaks?
Since newer eng and believe bigger cam would and better computer or chip be needed.
Oh one more thing he does have a line break from front brakes for burnouts not sure if that can do anything?

I have my twin brother coming by tomorrow he car nut to (he is restoring a 31 packard been in family since the 50s) and we will both take look and have him drive it too. Any help be appreciated.

I gota say was cool driving sons car and hearing sound of the headers man I miss my 68 bird I had but had sell it after kids where born needed the cash. But starting look for another one


Forgot to mention the extension housing on trans blew twice on him?