24-12-2012, 08:36 PM
(20-12-2012, 07:27 AM)C2K Wrote: It specifies the inducer size, provided nobody has fettled with it.
Nah, first two numbers has nothing to do with compressor size... It's to do with core and turbine shaft size...
In GTxxyyzzz - xx is frame size (does affect turbine size), yy is compressor exducer size (over 100mm, drop the 1, i.e. GT4202 = 102mm compressor) and zzz is the specific options - R = Ball bearing, V = VNT, K - Electronic Actuator, L = Water Cooled etc...
You've got to remember there's a MASSIVE confusion about T/GT series turbos and the naming system...
Garrett CHANGED the naming system half way through, which means that now there's great confusion over what the name of a product means, a "GT28" in old speak with a 53.00mm turbine wheel actually really means it's a "GT2560R" in new names, however the "GT28"s with a 53.85mm turbine are still a "GT28" -nowadays there's NO point in saying something is a "T25" or a "GT25" as it means nothing and simply causes confusion, say it's a "GT2560"....
Lots of people have done "bigger" than a GT2554, not many have done a GT2560... Thing is the GT25 frame is a bit big for the relatively small compressor wheels, they're not suited to smaller capacity ~5500rpm Diesels, perfect for petrols that don't need much increase in airflow though... Hence the GT2056 and GT2260 will do a better job than a GT2560 on our engines... Don't get hung up on the first numbers, look at the last numbers and their flow maps.
