02-26-2015, 06:11 PM
#117
(02-26-2015, 02:29 PM)barrote yep , the fellow´s with the 617´s dont know about pre cups
pitty looks like we have to disassemble them out
thanks anyway
the "up-rated" (roundish bottomed) 617.91 (NA) Prechambers are identical to the "up-Rated" Prechambers in the 616.
The 617.95 (Turbo) prechambers have a larger burn tube diameter inside and out, and will not fit in a NA head unless the head is machined for the lager tube. Also the holes on a turbo Prechamber are also larger than the Up Rated NA prechambers.
The up rated prechambers (roundish bottom) from a NA will fit in a turbo head, but do not use them as the burn tube OD is smaller than the bore in the head, and I think there could be a heat transfer (cooling) problem, but I do not know for sure. At the very least without the burn tube being snug in the head, it might sing and tend to brake, but again I am only guessing.
So to recap, turbo prechambers have larger burn tubes and holes than the NA versions do.