Originally posted by trashcar
Have two 421p aac sleeves split at ports niether saw temps above 240 both great running engines very high rpm. Replaced with factory ABC and head no further problems and will tolerate higher temps still would not recommend.Have tied palmaris BRB sleeve in r1wc works very well,the motor I was speaking of is his twelve with its one piece sleeve casting the new collari "sirio" is the same style.
Ok you are referring to the .21 Sirio WCR, which has that one piece casting sleeve...
I'm talking about .12 Sirio's and Collari's, which have removable AAC sleeves, and have no problems.
So we can rephrase your statement, saying that on .21 engines removable AAC's don't work yet.......but they work fine on .12's for quite a while now.
AFM