K been a member for awhile haven't really looked at this section but why is the 20b motors selling for 15-30grand? what makes it so expensive?

 

The motor's sell for $4k bare block.

The cars are more expensive b/c the swap isn't cheap. Do a serach in this section and you'll see what's involved.

 

The amount of parts and custom work to complete the conversion properly is more than most people expect. DO a search for posts under my name, will give you a bit of an idea of the work required.

I was able to get the car running 6 months after getting recieving the stock motor, only because I worked at a rotary shop and devoted all my time to the project.

If you are seriously considering it, talk to the guys at Gotham Racing in Fort Worth, since you are in Texas.

 

Can I get a 13b s4T engine and add the "special" intermediate plate and another housing/rotor,etc , 2 more injectors and the whole intake and add it to my Modified rx-4 (series4 g/box)?
Is this option any cheaper?

 

Than buying the whole engine.
And where can I buy separate 20b parts?
Obviously need to be imported from somewhere.

 

sure you can, but you'll need the e-shaft which will run you around $1800. thick inter plate will run you $900, extra rotor will run around $500, rotor housing $700, and tension bolt around $250 Even that, you'll need to port match your runners to the 20B runners which will cost you some $ for someone to do.
by the time you get all the parts needed to build a 20B, you can buy one from ebay for $4000 and still have left over to do other stuff

 

I wouldnt recommend doig a swap. Like he said 6 months of devoting full time work to his own car. It took me a little over a year to complete mine.