hey guys im getting a gsr swap to put in my 93 ej1. ive done some reading and it says to use the p72 to keep the use of the secondary intake runners. i was wondering can i use my p28 in the mean time in order get the car running and drive normally until i can source a p72

 

If you pick up a Blox IM for ~$180 just go with a chipped P28.

Most people ditch the stock IM to go with a single plane IM anyway, it's more simple and nets good gains at the wheels.

Another thing you can do is either gut the butterflies out of the stock IM or wire the IAB wide open with a zip tie or something. I wouldn't recommend this as a permanent solution though.

The only other advantage the P72 has over the P28 is the knock board. If you're not changing the compression ratio in the motor, with boost or pistons for example, then you don't need the knock board. Most tuners will tune by ear anyway since the knock sensor isn't really that reliable.