Red_Greddy_Si

Hello I have a greddy kit on my 99si and have it hondata tuned. my question is for you greddy kit owners will the turbo support 20 psi all the way to red line or should I opt for a upgraded unit like a gt28rs? What I have read about both turbos is that the output they claim is is nearly the same except for spoool characteristics being better with the ball bearing unit. My car spools faily quickly as we speak so that is really not the issue but I wuold like to stal internally gated so I can retain my ac and I really would not like to swap out anything but the turbo. the only other thing I would consider is if someone made a custom A/C compatible DP that was larger thanks for all the help guys

MachAF

The turbo you have T05D-18G is good to around 15psi.

There are few companys that make AC compatable manifolds. Fullrace, inline pro, lovefab.

Red_Greddy_Si

the DSM guys rum thier 18g and 20g's to 20 psi all day long so why wont it do it on a honda engine?

juggernaut

I just got rid of the greddy kit had one on my gsr/type r but from what I was told the 18g is good up to 15psi effeciently but after that they say the turbo doesnt produce anything but straight heat after that but your best bet is to ask greddy themselves. Oh yeah and my car was tuned to 11 psi stock map and I loved it didnt make big numbers because of my restrictions i.e. dp exhaust but still it is a nice beginner kit even though people on here have made crazy times with the kit.

Red_Greddy_Si

well this is what I have to work with so I am going to do anything I can to make good power with it. Right now the car is running 10.5 psi according to the hondalogger and it is fast 1st, 2nd, and a tad of 3rd gear are almost unusable at WOT. But this is a good thing I just have a new block with some forged insides and I want to see how far I can take it. I also have the type24 intercooler so heat is not that big of a issue right now. I also have a autometer dual channel intake air temp gauge and on the hot side @10.5psi it gets to just over 300degrees and the cold side is always in a couple of degrees of abient.

MachAF

Because their motors probably don't flow as well as honda's do.

You will once you go above 15psi the turbo won't be able to sustain that pressure at high rpms, the pressure will drop off.

WRX's have this problem. In the upper rpms the boost falls off becasue the turbo can't flow enough.

iiilgsrlll

What are your hp goals?