What are the advantages or disadvantages of using a Cosmo 13B-RE engine over the FD engine? Has anyone done this before?

 

The intake ports are supposed to be bigger. SR Motorsports uses one in their 8 second car. Greg also plans on using one, and he knows all of the secrets.

 

The stock HP specs of the cosmo 13b-re are only 220hp and the FD is 255hp, yet the cosmo, thearetically, should make more power - larger diameter runners, bigger ports, etc.

Why does it make less power?
Does it have more potential than a 13B-REW?
Which is better for power?

 

there had to be a reason to buy the 20B model.

theoretically the RE has more potential than the REW, but you'll have to work (or pay someone to work) to realize that potential. it has larger intakes, but the exhaust is trash - the REW is much more suited for upgrading, stock for stock. stock turbos on the RE were also smaller, from what i understand. the powerband that was needed to make the Cosmo what it was was not in the same vein as what was needed on the Rx-7, hence, the differences between the stock RE and REW.

better??? better will totally depend on what your goals and budget are - nothing else. personally, i think "most" people that have RE's will NEVER realize it's true potential and could have done the same as they have with an S5 13B-T. obviously, there a a few that have needed and used their RE's very well.

 

I think a combination is the way to go.
I have the RE plates due to the larger ports, but the REW has bigger exhaust sleeves so you can either buy the REW housings or just replace the RE sleeves with the REW.
THe REW has stronger stationary gears so that is an upgrade that can be made to the RE as well.
That setup works well.
Having said that, the REW is the final engine made by Mazda so I guess there must be some reason to use that model.

My 2cents

 

The RE has no more potential than the REW, they are more alike than different. In fact I would say the potential is the same.

Just focusing on the Keg sans intake and exhaust componens.

Rotor Housings RE housings have more restricte exhaust sleeves, but sleeves from a T2 or REW will fit RE housings, othewise the same.

REW has better internal bearings (9 window vs 3 window), and runs higher oil pressure from the same pump. REW also has stronger staitionairy gears for a higher factory redline, REW redline is 8k in an FD an RE would never rev past 6k in normal operation in the auto trans only cosmo

Eshaft and rotors are the same

REW front cover has no place for a distributor and the crank angle sensor is taken off the eshaft pulley

Side housings, RE has bigger runners, with the same size and shape secondairy ports but smaller primaries, the casting material is there for the REW runners to be ported out to RE size,

RE and REW side housings have differnt holes drilled and tapped for the engine mounts and RE lacks one bolt holes used with the REW front cover, but the castings seem to be the same, such that the RE housings don't have holes drilled and tapped for the REW engine mounts, but there is a place in the casting for them

Intake manifolds will swap between RE and REW engines.