i gots a 91 prelude si
is it worth getting a b20 vtec in it or shouldi just stay with the b20a5

 

b20 vtec... talking about a b20b with vtec head? won't fit. basically your only options are (reasonably speaking) h22, boosted b20a5 or jdm b20, or NA build. you will find that boosting will be good as long as you build the motor accordingly. however if money isn't an option, of course anything is possible. its just how the motor sits its hard to a swap. some people have done a vtec head on the b20a5 block... not worth it in the end, from what i've seen/heard.

www.preludepower.com has the best third gen section available. look around, search and post up! goodluck.

btw, i have a boosted b20a5, you'll see me over there runnin for prelude of the year.

 

well the h22 is gonna run me alot of money but how much would the jdm b20 cost?

 

Also what engine can bolt right into the 91 Prelude?

 

Custom R & D...

 

OK let me help you understand somethings about your Lude.

1. It was the testing platform for all the newer B series motors and FRM sleeved H22
2. It does not interchange with any of the newer B series motors
3. The only motors that bolt right in without any type of swap mounts is, B20A(JDM version of the B20a5), B21a1 or the rare B21a(JDM verison of the B21a1)

The only motor(s) supported for a motor swap into this chassis is the H22. I know because I had the mounts made and produced and now sell the kit(email if interested).

As stated above, your options are limited to the B20a5(20A), B21a1(21A) for lowere cost. However these motors do not rev to high heaven like the new vtec power motors so don't even try it. Once you start reving past 6800 rpm and hit the 7200rpm red line limit constantly, you will start hear a lovely noise come from your motor and then eventually a nice sized hole will make itself appear in the side of your block.

The B20a5(20A) motors are the most reliable of the two motors, especially for boost, because it comes from the factory ironed sleeved. With a compression of 9:1.
The B21a1 has FRM sleeves and was the first Honda Motor to try this technology and come to find out that the OEM rings will not last for long, which cause oil by pass and starts burning oil by the quart.

The nice thing about these motors was that they make as much torque as they do Horsepower.

The strongest NA powered B20a5 is currently owned by a guy in vegas who is a member on this site as well, and it has Individual Throttle Bodies, complete engine work and options for NOS. And is currently making 186whp.

The strongest boosted B20a5 is on here and www.preludepower.com his member name is TonyBaker21 and he was dynoed at 400+whp. So there is potential for these motors but not in the High RPMs like the B-series motors.

And if you ask the question is it worth it to swap, well ask yourself the question, what will make you happy. Because it comes right down to your financial situation and what you want to put into it.

Average cost for all options:

1. Properly built and boosted B20a5(20a) - $2000-$4000
2. H22 swap - $3500-$6000
3. Hybrid VTEC conversion - $4000-$????? (reliability ?????)
4. Properly NA build - $3000-$10,000

The prices range due to your power goals will range.

Again if you want the H22 options email me at: onefunrydperformance@q.com
I am also a member of preludepower.com and support this chassis.

And another note to add, the H22 swap kit will support all the H/F series motor swapps into this chassis as well.

 

what ab out a 90 prelude si. i already emailed you. but my question is what motors can go into a 90 prelude si without changing a whole lot!? and about how much will it run me?

 

If you are just looking to swap the motors that came with your 90 Lude, then either purchase a B21a1/B21A or B20a5/B20A(88-91 Prelude B20A)

If you are just looking to get the same power those motors will be drop in. You can boost the B20a5 for more power, but there is a limit to how far it can be boosted.

We have seen dynoed at 400whp. Past that we have not been able to see anyone go that far yet.