jtothawhat

iTrader: (7)

So my car was dyno'd last weekend, and I was upset with the way my turbo spooled, it had a lot more lag than I thought it would, boost coming on at 4,000 not too sure where I made full boost, but it was over 5,000. But long story short I made 287 whp with 13 psi in my 1.6 with a T3/T61 non-BB turbo. The shop who tuned my car (Sound-Performance) known for there Supras said with a smaller turbo my car would make 300+ whp at 12 psi, if I where to get a new turbo would I have to re-tune the car, even at the same boost?

Here are the three turbos I can't decide on:

-GT2871R w/ T3 .63 exhaust housing
-GT2876R aka GT25/40R w/.63 exhaust housing
-GT3071R w/ .63 exhaust housing

I want a good spool, but make the most power. I know they'll all have different power bands, etc. but which is the best balanced turbo for 300+ whp?

neogenesis2004

iTrader: (12)

Yes, you HAVE to retune. You have to retune your car whenever you make any changes in your setup. I'd get number 1 out of your list.

Is your motor built? Or at least does it have forged rods?

patsmx5

iTrader: (16)

Definately NOT a turbo guy, but you retune it if you swap turbo's I would think. What are you using for engine management? MegaSquirt is popular on this forum.

jtothawhat

iTrader: (7)

I'm using AEM EMS with 750CC injectors, fully built motor with .20 overbore.

Engine specs

-Wiseco pistons
-Carrillo H-beam rods
-Balanced crank
-Blueprinted/O ringed block

paul

iTrader: (21)

Someone on this forum is selling a brand new GT2871R in different trim
https://www.miataturbo.net/miata-parts-sale-trade-5/f-s-new-garrett-gt2871r-0-64-r-14084/

bryantaylor

iTrader: (5)

yay, you defently have to re-tune. the new turbo with be flowing different, so the current tune could be close, but close can blow the motor too. are all of your hotside gaskets good?

Savington

iTrader: (31)

You must retune. Your current maps will be close, so they won't be starting from scratch, but adjustments MUST be made.

jtothawhat

iTrader: (7)

Okay thanks, guys. Now I have to find a good tuner in the San Diego area, I know Bisimoto Race Engineering is close...

Bochinam

I've been thinking about replacing my T3/T4 with a GT3071R. I'm looking for similar power levels 300~350 whp. Please post back and let us know which turbo you end up with.

Kelly

iTrader: (6)

The 3071 will take you well beyond 400 whp.

magnamx-5

iTrader: (7)

Ok does any one esle think his 280-300 whp at 13 psi out of a 1.6 is alittle high. Even i think it is a little high. Sure y8's and airbrush did it on there NB's but who else has seen a 1.6 hit numbers like that before. Please jtothawhat post up a sheet on this i gotta see it if it is true i will most def look into a huge *** turbo. And try to figure out what you are doing right.

jtothawhat

iTrader: (7)

It's not a 1.6 more like a 1.7 lol, I will post the dyno sheet as soon as it's emailed to me.

Braineack

iTrader: (62)

I have around 250rwhp at 13psi. with a stock block. The 60-1 is highly efficient in that CFM range, I could see it possibly.

magnamx-5

iTrader: (7)

Hmm this gives me great hope for my 1.7 liter. Maybe i should step up to a bigger turbo next year. But still scot hayden etc took quite a few psi to hit 300 whp on his setup i think he made 320 or so at 20, jasono made 300 someodd at 16-17 psi. aswell i look forward to some more info bud.