j_tso said:In reply to Pete. (l33t FS) :
I remember side seals being an issue in Grand Am Cup, don't know if Speedsource found a solution before moving to the 20B PP in the Rolex series.
I do believe that moving to a peripheral exhaust engine WAS the fix.
The thing is, rotaries thrive on being heavily loaded. The move to side exhaust increases low load efficiency, but at the same time, heavy load is what hurts the side seals... so it is kind of a problem.
Maybe if Mazda reverted to 1mm side seals they would have had fewer issues. It would still not solve the housing warping issues at the exhaust ports. Mazda went so far as to extend the cooling jackets between the ports and the coolant O ring area, which is why you can't port the exhaust much and especially cannot have a bridge ported exhaust.
I keep wanting to try a peripheral intake/side exhaust engine with a cheapo 4 port JDM engine, but it seems like a lot of work for not much gain. It might have a lot better emissions than the bridge ported '74-78 type 13B that I use now, which would really be the only reason to go for it.
