I don't claim to know anything about anything here, but having done the full heater box conversion (fresh air type boxes) for 1-5/8" merged exhaust on my 2276, I wouldn't recommend doing it unless you really want heat and you have the tools, skills, and TIME to tackle this job. The stale air heater boxes will be a little simpler and cleaner looking, but I decided that I wanted to use the fresh air heater boxes for my conversion. Admittedly, I wanted the boxes to look close to factory, but if you wanted to take a lot of the work out of building them, you could eliminate the factory style seam used to assemble the heater box halves and just stitch weld every 4 inches (oops, I mean every 101.6mm
).
Here I formed the tin to fit around the bigger 1-5/8" (42mm) pipes, but I went a little too far and they were actually able to fit 1-3/4" pipes snugly:
This is after I started shrinking the opening back down to fit the 1-5/8" pipes:
My engine uses 48mm IDF's and I wouldn't hesitate to use them again, but I can't comment on the IDA's since I only have limited experience with them. Some guys praise them, others curse them...but then again, many don't understand or want to learn to tune dual carbs, so that may be some of the cursing we hear about.
I like the fact the IDF's allow for air cleaners, so that was a big part of why I used them instead of IDA's....well that, and they were less $$$!!! My Big Beef intakes don't allow the decklid to close with a standard size air filter, so I had to use these K&N tapered filters:
As for running with seat warmers, they are for little (sissy) girls....I know this because I installed seat warmers in this pair of seats I built so I could be a little sissy girl....a WARM little sissy girl!
The problem is seat warmers don't defrost windshields!:
Andy