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hi im buying a 97 model GST25T auto transmission. Im planning to modify it as its all pretty standard under the bonnet but i was wondering how far should/could one take it considering its an auto trans or doesn't this matter? im talking about upgrading the turbo mainly. thanks

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https://www.sau.com.au/forums/topic/37029-upgrade-query-for-gts25t-auto/
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dont upgrade the turbo until your after about 220rwkw or higher.

just do

intercooler

exhaust

apexi safc

boost controller

decent tyres

once you wanna go over 220rwkw or more then get your stock highflowed or an aftermarket.

adding a new turbo onto your stock components will be a waste, your ecu will do boost cut, the boost will be average, the stock intercooler wont flow enough, your exhaust will be too small etc.. turbo seems to be the last thing to upgrade in a stock r33 from all the quotes and research ive done

you can easily get to 200rwkw with stock turbo, just more boost (about 12psi)

also speak to an auto trans specialist and get a stage 2 shift kit on the auto box. will allow it to shift quicker and better and provide more torque, could be more than the stock manual box with a stage 2 shift kit, unsure exactly but definetly worth looking into

Well, my auto was fine until i got it serviced!

When it breaks it's time for a 5 speed as the missus has never driven it anyway!

Auto skylines run a more conservative ecu map and generally do not respond well to increased boost, an aftermarket ecu is a good idea there.

paulr33 have you got an auto? if so what mods have you done, what ecu do you use? what rwkw figure do you have, and have you done anything to the auto box?

mines auto and i have everything you listed on my car and my next major upgrade is highflow the turbo, but im still unsure about what ecu to use and how the auto will hold up.

I want to buy the e-manage but noone can give me a definate answer if the ignition harness works on the auto.

we are about to push the limits of my auto trans so when it brakes i'll let you guys know.

yeah its correct that auto ecu's do not respond well to increased boost ..... an EBC was the first thing i did .... the we had all kind of fuel problems .... which took new fuel pump, safc II and a new o2 sensor to smooth out ...... but it was too late one of the injectors leaned out and an engine rebuild was in order. Now all my ratios are pretty much spot on.

Mine did 246rwhp before the engine died ..... thats with 3inch catback zorst, SAFC II, Blitz S spec EBC, bigger fuel pump and airpod.

Now its coming back with forged pistons (which im running engine in today), FMIC and hopefully a new hi-flow turbo depending on the budget and i guess new auto trans cooler is in order too cos they expect it to reach 350rwhp which is being estimated as about breaking limit for trans. Heard new auto trans are only $200 tho cos nobody wants them :D

Anyway thats my little expermient .... good to see more people modding the autos ..... go kick some manual butt at the drags :D

Most auto trans shops that do performance work should be able to adjust the valve body for a 'quickshift'. The quickshift is often reffered to in 'stages' really it's more to do with 'slip', stage 3 when manually shifted 'bangs' into gear with no slip. The torque convertor can also be modified allowing a higher stall speed. I'd say between 2500rpm and 3500rpm would be fine for a road going line'.

Sounds great Nizmo! i thought i was the only one around trying to get a decent figure from an auto. What ecu are you running? I have no idea on what to get, everyone gives me different advice....

Please post your results or contact me when its done nizmo as id be very interested

An auto at the drags is the way to go, sounds like you have had some expensive fun Nizmo!! when I break my auto i will use that as an excuse to fit a manual as dorifto is more fun and less work with the clutch factor, and without a computer deciding what gear i should be in!!

Yes I originally got a auto for the wife she drives it most of the time, my wife and I both want more power out of it but we are only chasing around the 200rwkw, we just done most of the suspension and plan on getting all of the exhaust done next then the Wolf and the bosch 910 will go in and turn the boost up a bit and see where we are with that, maybe a turbo upgrade with some injectors just to make sure that I can make that power reliably all day and that I know that I'm not pushing the standard to a inch of it's life. I have also been thinking about some small cams, ooh and a new intercooler and tranny cooler will be fitted some where in there as well.

my auto blew up after 180rwkw

went exelent for about 1 year then it just crunched itself while cruising down parramatta rd at about 80km/h takin it easy

it just wen crunch crunch then would not go over 40km/h

its manual now :(

more fun

i still miss the auto sometimes though it went so well

paulr33 have you got an auto? if so what mods have you done, what ecu do you use? what rwkw figure do you have, and have you done anything to the auto box?

mines auto and i have everything you listed on my car and my next major upgrade is highflow the turbo, but im still unsure about what ecu to use and how the auto will hold up.

I want to buy the e-manage but noone can give me a definate answer if the ignition harness works on the auto.

no mine is 5 speed. mine only has pod filter and a bigger muffer. stock ecu. 141rwkw. its manual so no mods for the auto box. i actually dont know that much about cars i just read what other pleople post and do my own research etc, all of my ideas/suggestions etc are really from what ive read on here and researched

what power are u making with those mods? should be about 190rwkw ish?

if it was manual i'd say pwer fc but no idea if power fc works on auto.

when u look at cost of safc and avcr (or a good boost controller) and get them tuned its almost comparable to just get a power fc (with boost kit) instead of the safc and avcr. well when u compare overall cost vs overall power increase and managability. when you wanna go furhter much easier to change stuff with the power fc. also you dont have the stock ecu limits such as boost and fuel cuts. you get bonus stuff (from the powefc) like changing the rev limiter and ignition maps instead of just boost and fuel maps with the safc + avcr

See SydneyKid's post about getting 250rwkw and what's needed. its a good guide for a rough figure and shows what one should expect for various bits

http://www.skylinesaustralia.com/forums/sh...ight=power+rwkw

my thoughts anyway, i could be completely wrong

no mine is 5 speed. mine only has pod filter and a bigger muffer. stock ecu. 141rwkw. its manual so no mods for the auto box. i actually dont know that much about cars i just read what other pleople post and do my own research etc, all of my ideas/suggestions etc are really from what ive read on here and researched

what power are u making with those mods? should be about 190rwkw ish?

if it was manual i'd say pwer fc but no idea if power fc works on auto.

when u look at cost of safc and avcr (or a good boost controller) and get them tuned its almost comparable to just get a power fc (with boost kit) instead of the safc and avcr. well when u compare overall cost vs overall power increase and managability. when you wanna go furhter much easier to change stuff with the power fc. also you dont have the stock ecu limits such as boost and fuel cuts. you get bonus stuff (from the powefc) like changing the rev limiter and ignition maps instead of just boost and fuel maps with the safc + avcr

See SydneyKid's post about getting 250rwkw and what's needed. its a good guide for a rough figure and shows what one should expect for various bits

http://www.skylinesaustralia.com/forums/sh...ight=power+rwkw

my thoughts anyway, i could be completely wrong

Power FC doesn't work with the Auto I've tried, the PFC doesn't give the auto ecu a TPS signal and a few others so the auto doesn't know when to change gears, I posted the results when I tried it if interested do a search, should still be there. That's why I got a Wolf3D they work with the Auto's I just haven't got it installed as yet.

Thats no good MYGTST i currently have 181rwkw and my box still feels fine.

paulr33 i have spoken to sydneykid about this in the safc thread and im just going to keep the safc and get a itc....its the cheapest and easiest option for me.

Im not wanting huge power, just whats listed in my sig plus a cam gear, highflow T3 and ITC and fuel pump etc which should hopefully give me a reliable 220-230rwkw or so.

As nizmo said the auto boxes are cheap as so if i blow mine up i can just buy another one cheap and before i put it in the car ill get it strenghtened.

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