Sorry if this has been answered before but i am new and i dont see a search button. anyway is a 20b engine able to fit in a 3rd gen rx7 if it is will the 13b tranny bolt up to the 20b . and will i need a 20b ecu and stuff to run the car

 

Yes, a 20B will fit. It is a very expensive modification, a few places will do it for around $35k. BTW, the search button is in the upper right corner.

 

It is not a simple drop in.....modification needs to be done. Thats why it costs ~35k.

 

what makes it so expensive?

 

the engine is expensive, doing a lot of custom work is expensive, read about the 20B at http://www.concentric.net/~Asam/index.html

 

If you go into the performance mods forum, there is a small 20b forum that was just started within there, you can get a little bit of knowledge there, and alot more from using the search button, which is right below the red rx7 in the upper right hand corner.

 

i can get the engine for $3999 plus shipping, what kind of custom work is needed? if i got a 2nd gen would i still need work?

 

yeah you need work either way, there is too much work to list here but here's a small portion. All of these need to be replaced with higher performance peices.

ecu(I would say motec)
fuel system
intercooler
radiator
clutch
twins converted to non-sequential, or a big single turbo and all the parts to go along with

You would probably use a stock FD transmission since it bolts up with a FD clutch/flywheel.

Plus if you are spending this kind of money on the prodject then you want a good/reliable engine, so I would suggest you get it rebuilt with a porting job of some kind.

If it goes in a 2nd gen then I think you need some kind of special motor mounts, but don't know too much about them.

If it goes in a third gen, then you can either buy a modified subframe/spindles from pettit to shoe it in there which is 2300.00 plus your old one.

Or you can go the PFS way and move the transmission back, cut down the ppf, and shorten the driveshaft, and shoe horn it in there that way.

Oh and then you have the amount of labor/fabrication it gets to make it work. Don't plan on doing this even yourself for under 25k.

There's more to it than this, this is just a general idea. Again I suggest you do a search..

 

www.alamorotary.com has allot of 3 rotor conversion info