GT28RS A/R 64 will Kill LIFT ?? [Archive]

sillycar09

03-23-2010, 02:27 AM

I saw a msg from Turbokits.com...
Yes, way back when we were originally making a kit for the GTS we tried the GT28R, .64 AR first. The AR and exhaust wheel were too small for the 2ZZ and the back pressure stopped the car from going into LIFT. GT28RS .86 AR is the smallest you want to go on the 2ZZ.
Mine is Turboed Auto GTS with 9.1cr....
I want FAST RESPONSE and turbo spool up at around 2500rpm...
But...If I choose A/R 64 ~~ My LIFT will DIE at 6 k ??
Hope you guys can help !! Thanks !! :AF:

c3ll

03-23-2010, 03:15 AM

this should be in the forced induction forum imo ...

sillycar09

03-23-2010, 03:29 AM

Thanks for fast reply !
Hmm... do you know that A/R 60 GT28RS will kill LIFT function ??
Actually I love A/R 60 ! FAst Spooling !! But after I saw msg from the Turbokit.com ... I'm worry my LIFT !! :(

GSBoek

03-23-2010, 05:23 AM

this should be in the forced induction forum imo ... Indeed.

:moved:

sillycar09

03-23-2010, 05:29 AM

Yeah ! Just Moved !! :)
Hope can help !! :(

darkmajin

03-23-2010, 06:35 AM

lol someone help him

sillycar09

03-23-2010, 09:42 AM

Yaya!! Someone pls help !! :gayfight:

youngxlos

03-23-2010, 10:51 AM

just go with the .86 A/R

sillycar09

03-23-2010, 07:19 PM

ok ! Thanks !

smart_rocket

03-25-2010, 11:41 AM

hey -Vin-
what is your psi and rpm-limit target? Anyway I'd go bigger A/R and highboost... smaller or bigger A/R it's still a GT28RS!!! GT28RS will kick your ass also with bigger A/R and even provide higher topend power.. :love: damn so proud of ya :headbang:

other catch... you'll require bigger injectors for your increase in power... still have your plenty hole injectors, you can buy them back if you like... I'll go bigger soon... they are still new...

bajan_speed

03-25-2010, 02:18 PM

From reading here it seems they experienced that problem with the particular style manifold they were using and the fact that they were using a piggyback to tune.

There was a guy with a matrix that was using a gt28r on the stock engine some time back and he still had lift but he designed his own manifold. I think Diskace was his screen name on 9th gen. To be safe tho just go bigger you can't lose the turbo will still spool pretty quickly

sillycar09

03-26-2010, 02:34 AM

hey -Vin-
what is your psi and rpm-limit target? Anyway I'd go bigger A/R and highboost... smaller or bigger A/R it's still a GT28RS!!! GT28RS will kick your ass also with bigger A/R and even provide higher topend power.. :love: damn so proud of ya :headbang:

other catch... you'll require bigger injectors for your increase in power... still have your plenty hole injectors, you can buy them back if you like... I'll go bigger soon... they are still new...

Hi ! Buddy !! I'm using 38mm Tial wastegate with 7psi now...
Everytime when I race , I will just use 1st gear and 2nd gear to rev 7k - 7.8k rpm only and 3rd gear rev 6k =( Max speed )
Big Different compare with Manual 6 speed Gts~~
Manual 6 speed when shift gear from 1st gear to 2nd gear...the LIFT still activated !! But for an auto gts...the rpm will directly drop to 3k rpm !! and need a few second to hit LIFT at 6k... Hope you understand what I'm saying :o:
I'm prefer .64 actually but worry will lose power at LIFT because of back pressure !!
I plan to boost 1 bar in my future ~~ And It also the Max boost for me (1bar)
Ok ~ If I want , I will buy from you my fuel injectors back !! :love:

Oh ya ! I found this dynochart comparing GT28RS A/R 64 Vs A/R 86

http://i6.photobucket.com/albums/y239/hilary33/DynoRunRR28RS17psiPump.jpg

A/R 64 look nice in low to mid end ...

blinding-gts

03-26-2010, 04:29 PM

Mine is Turboed Auto GTS with 9.1cr....
I want FAST RESPONSE and turbo spool up at around 2500rpm...
But...If I choose A/R 64 ~~ My LIFT will DIE at 6 k ??
Hope you guys can help !! Thanks !!

The answer is both yes and no, it depends on the tune and the amount of boost going into the engine.
The reason a .64 trim would be a problem is beause it actually chokes due to backpressure. Lift kicks in and the car basically bogs or won't go past 6xxx+ rpm (depending what rpm you have your lift change over point setup). At the time this was going on a lot was diagnosed to be manifold design issues, then some found the A/R was too small at .64. Get a .86 trim and you shouldn't have a problem worrying about this if you want to boost more. Also, the GT28RS spins up pretty damn fast and hangs in there all the way to the higher rpms from my experience with it.

smart_rocket

03-26-2010, 07:29 PM

Update: with the auto trans installed the car has put down 570hp to the wheels at only 26psi. Not too shabby.

great vin, maybe you wanna ask MWR for some best suggestions... ;)

sillycar09

03-26-2010, 10:05 PM

The answer is both yes and no, it depends on the tune and the amount of boost going into the engine.
The reason a .64 trim would be a problem is beause it actually chokes due to backpressure. Lift kicks in and the car basically bogs or won't go past 6xxx+ rpm (depending what rpm you have your lift change over point setup). At the time this was going on a lot was diagnosed to be manifold design issues, then some found the A/R was too small at .64. Get a .86 trim and you shouldn't have a problem worrying about this if you want to boost more. Also, the GT28RS spins up pretty damn fast and hangs in there all the way to the higher rpms from my experience with it.

Thanks for your info !! Last time I'm using GT25 with A/R 64... It can past above 6k rpm to 7.8k rpm...but the power drop after kicking LIFT !!
I found the problem because of turbo too small ~! :wiggle:
I will get a bigger A/R ~! :wiggle:
Oh ya ~~ I thought GT2871R A/R 64 with smaller trim better than GT28RS .86 ??
GT2871R can make more power ~!

Barbarian

03-30-2010, 08:35 PM

Oh ya ~~ I thought GT2871R A/R 64 with smaller trim better than GT28RS .86 ??
GT2871R can make more power ~!

you've got everything mixed up.....

c2gas

03-31-2010, 03:12 PM

gt28rs (gt2860) with 0.86a/r is your minimum, dont go any smaller a/r on the GTS ( useless anyway as you have power in high rpm)
FORGET the gt28r (gt2540)!
we have gone thru with the same problem on our gts turbokits.

sillycar09

03-31-2010, 08:01 PM

gt28rs (gt2860) with 0.86a/r is your minimum, dont go any smaller a/r on the GTS ( useless anyway as you have power in high rpm)
FORGET the gt28r (gt2540)!
we have gone thru with the same problem on our gts turbokits.

Ok ! Thanks you very much !!
I'll go for A/R 86 ~ !! :wiggle: