save yourself lots of hassles and buy a d16 atleast...the d15 rods are like toothpicks and you wont be able to run more then 5-7lbs safely. Convert to MPFI it can all be found on 88-91 Civic si, ex and crx HF's. If you want to go fast dont bother with the stock DPFI that you have inherited...The 4speed will be alright if your going to run boost due to that long ass gearing, if you want to go 5speed look into a DX trans, the si will work too but your going to have a little less gear and with boost sometimes that hurts more then helps unless its a full fledge 1/4 mile car.