Does anyone know if 48/52 turbines from PE are going to give me massive lag... or just a bit... anyone have ideas on what the powerband will be with those turbines?

I just had an idea... Maybe this could go in the 'Performance Section' ?

Not to be a smartass... Just saying.

-Wes

sorry, when i posted i thought it was in the performance, my bust

lol. I presume you are talking about the compressor trim?

yes

The majority of lag will be determined by the A/R rating of the exhaust housing, not so much the trim of the compressor side. It gets quite technical but the short and skinny of it or good rule of thumb is the bigger the A/R rating of the exhaust housing (turbine) the greater the lag.

Standard GTR turbos are T25's with a turbine A/R of .46, and you should see full boost around 3,200 rpm all day long. Bump the same turbos up to .64 with slighly larger wheels on both the turbine and compressor side and the boost threshold increase. So if we look at some basic Garrett turbos this can give you a good example.

For single turbo conversions a Garrett GT30 turbo with an turbine rating of A/R .64 on an RB26 that is factory standard should see peak boost of 1 bar (14.7 psi) at 3,000 rpm and can make up to about 450hp. If we change the exhaust housing to one of an A/R of .86 peak boost climbs to around 4,100 but we now can make 500-525hp with the same compressor side.

Good replacement turbos for a GTR are HKS or Garrett GT 25-30's. They have smaller wheels on the exhaust side but yet have an exhaust A/R of .64. Full boost should be around the 3,800 rpm mark yet getting 600-625hp isn't a problem. They are the most effeicent (streetable) turbos on the market.

Again to try and answer you question you would need to post the full specs of the turbos, and odds are unless I'm very familar with them it will be guess work. All depends on what sort of power you intend on making and how drivable do you want it.