As stated above the only engines that bolt up to the 88-91 ludes are:
B20a5, B20A-JDM, B21a1, B21A(rare)
Aftermarket swaps are: H22, H23, F20B, F22B with the H22 swap kit.
I have invested a lot of time and effort into getting all the information and some parts to make this swap as easy as possible.
Performace Upgrades for 88-91 Preludes
H22 Parts list
Read those links and email me at:
onefunrydperformance@q.com
I am a owner of the 3rd gen lude and that is why I decided to invest into my part time business to get aftermarket parts made for this chassis.
I am still trying to get the B series motor mounts swap kit made, but it is slow now, but I will keep at it.
To do a simple cost analysis for doing this swap vs keeping with the B20a family take a look:
H22 swap = $3500 - $4500 = 200hp 161tq
B20A(JDM) = $900 - $1500 = 140hp 131tq
I can tell you from personal experience, the H22 swap is the best power upgrade and more reliable due to parts are everywhere for this motor and tranny. Plus the power potential is greater.
The B20A is just an reliable motor swap but it is good for boost. And the cost to boost that motor is: $1500 -$3500
Sean