What is the difference in the regular UIM and those that have raised
stamped letters like 13B on the top? I've seen member's pix with at
least 3 different versions?

thanks

 

The JDM UIM is similar to the USDM one but is missing the AWS so less block off plates are needed.

You're probably referring to the 13B-RE UIM, which is from a Cosmo, not from the FD. In order to run it you need the matching LIM. I don't run it b/c I want to keep my GZ LIM, which isn't compatible with the 13B-RE UIM.

Makes sense? Lots of acronyms in there

 

Does the 13b-RE combination flow significantly better? Any other issues with compatibility with the FD systems? Just curious too.

 

From what I have read on here and have seen personally, the 13b-re does flow slightly better. Since the UIM has longer runners you MUST have the re-lim for it to be bolt and go (basically re-alliterating what Rich said). The parts really arent that expensive, and they look amazing polished, however, IMO the money could be spent better elsewhere.

 

The 13B UIM has much larger and slightly longer runners, it also has a parabolic chamber (allows the air to tumble before entering the runners)

The RE UIM was designed in nature to have better bottom end torque.

I'm currently doing the conversion (with a twist)

The RE UIM mates to the REW TB, but leaves a small gap that needs to be filled with weld or devcon putty.

It may be a better stationary modification, but I agree with Bryan (money could be better spent)

The main reason I jumped on this project was vanity.