TegR

My garret turbo was on it's last leg so I decided to go with a bigger turbo. I noticed some differences. I was on 15psi on the garret, now I'm running 10psi with the sc6152S because I haven't gotten re-tuned yet. Car feels just as fast as before, but I actually have better traction now. Is that due to the it hitting full boost later in the power band? Also this thing is quiet. I mean the garret I could hear it start spooling at 3500rpms and would get pretty audible at full boost. But with the sc61 I can't hear it at all. Does it get audible at higher boost levels? Also is it normal for it not to spool at idle? Strangely the turbo lag that I have now doesn't bother me as much as I thought it was going to.

A.E Motoring

iTrader: (1)

u need to retune that car with that new turbo

TegR

Yeah I know that much. I wasn't asking about power differences.

90teg

I know my sc61 doesn't whine like more turbo's, so I'm guessing that's normal.

HiProfile

Its probably quiet because the compressor wheel is spining nearly half the speed and its runing lean. A bigger wheel at 50% less boost means much slower turbo rpm's, and a bigger turbo at X psi as a smaller means more flow, meaning a need for more fuel. If you feel safe at 10psi, push it to 15psi. It should be just as lean as 10psi is currently It may slow the spool time though, as running 13:1-14.7 is great for power, but FI cars run <13:1 for knock supression.

There has been threads before on shaft speed at idle, and its not uncommon for a big turbo to come to a complete stop at idle on a Honda.

TegR

My af's are 12:1-12:3 according to my wide band across the board. So unless that is lean then I think I'm doing ok. So this turbo is suppose to be quite?

beaver

From my experience the SC61's dont get very loud until you start running about 18-20psi and get into the turbos efficiency range.