GT28R: interal or external wastegate?

terbow said:
yea u want the 5 bolt non ford style. otherwise youd need a new DP. go here.

http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=GRT-TBO-004&Category_Code=GRT

for the housing u have a choice of : .64 or .86 ar

.86 is what mam supplies. it wil have more lag but lots of top especially at 15+ psi, or the .64 will spool it faster but you lose it up top. if ur gonna run 15 psi id go .86

the first option is what u want as far as turbine flanges go (5 bolt and t25 flange) if your using a msp mani or anything msp related.

for the compressor housing option at the bottom just put standard and u will get a 3" inlet that u can slide a coupler on.
now, that says GT28RS... but the setup I'm choosing makes it a GT28R?

isn't this what i want? http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=GRT-TBO-002&Category_Code=GRT
 
i know it's going to sound odd, but the RS spools up too quick. I want to keep traction in 1st gear (autocross). I'm told the R spools a little slower, and the RS is $200 more expensive.
 
another newb question (by the way, thanx for being patient with me):

if i get it with the internal wastegate, what will the "stock" psi be? it's the spring inside that controls the boost, correct?
 
LinuxRacr said:
(mswerd) Terbow, where do you see full boost with the RS?

i dont have the rs now :( but it wasnt till after 3k, if i had a mani it would have been better but with a 3" turboback, fmic , and intake it was like 3200-3300 ish if i iremember correctly for 9.8 psi.
 
Rogue said:
another newb question (by the way, thanx for being patient with me):

if i get it with the internal wastegate, what will the "stock" psi be? it's the spring inside that controls the boost, correct?

yupper, if u get the RS it will be 10 psi, not sure about teh R. on external u can change the spring on the internal u cant u need a new can to change psi. ATP turbo has lower cans as well.
 
since you mentioned you didn't know what I plan on running here's the breakdown:

INJEN CAI - Turbohoses hard pipes - Turbohoses FMIC - Single runner intake manifold - NSN thermal Spacers - MSP exhaust manifold (Extrude honed) - GT28R - MSP S-pipe (Extrude honed) - Vibrant 3" Exhaust - MSP ECU for now (EMS in short future - Microtech?)
 
im going to reedit this so i can better explain.

the RS should fit with what u want (the compressor is larger so its over more toward the driver side, the couplers should take up the slack. however the R looks pretty tall with that extra flange on it. i dont know that it will fit. the MAM kit was made with the 28 in mind. we msps dont run the R, i dont know if theres any MSP running it at all (non mam/custom kits) to be honest. if there is u should ask how it measures up to the RS.
 
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GT28R = Good for about 290-300 WHP
GT28RS = Good for about 350-370 WHP depending on what turbin housing you decide to use.
 
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