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hey guys,

what would be the best way to go about making a really responsive rb25? i would like to keep the standard turbo, not really interested in playing around with the diff but if there is any drop in diffs centres from other cars that are a bit shorter, might think about it.

cheers for your help

p.s tried to search but there was not mush with the standard turbo..

cheers james

aggressive tune (heaps and heaps of ignition timing, cant stress this enough)

standard turbo

normal FMIC

heavy duty clutch

some good tyres ($300+ each)

good suspension

pineapple kit

camber kit

castor kit

good cold air intake

good boost controller

consider 4.3 diff gears

fuel pump

good exhaust setup

tune the vct

thats probably it, no need for cams, cam gears, manifold, etc

my r33 has all of the above except diff gears and it runs great

has amazing response, great on fuel, excellent on the street

great for twisty roads etc, one thing my r33 doesnt have is new shocks, it has the standard ones still

here is mine in SAU garage

http://www.skylinesaustralia.com/forums/in...view&id=270

i meant its not exactly a mines setup, but its pretty quick for what it is

Frankly, i habe bene mucking around Skylines for 10 years, (others far longer) but to this day the most impressive street car i have driven and been in was an R33 GST25T with HKS 2530, Greddy inlet and 256 cams. The thing was more responsive then std, mdae 230rwkws and i would loved to have seen the torque curve. It ruled on the street. Track it wa a bit breathless over 6,000rpm, but it was all round better then the HKS T51, 3040, Trust T67 , Turbonetics T66 etc that followed the 2530 :P

The Mines engine built alone cost $65,000 AUS.

Auto Style in NSW made a replica of the Mines R34 GTR and the engine was built and tuned in Mines Japan then shipped over.

Mines concentrate heavily on over all balance then just out right power.

Light-weighting your car would be a start = Carbon Fibre anything you can think of or take it off the car.

Engine wise, air intake (Keep standard airbox, upgrade panel filter).

Up your boost (Boost Controller) to a safe level, I think RB25's run a stock boost of 5psi..? I am guessing about no more than 7psi, depending on the condition of your standard turbo.

If in a good condition you might be able to go higher then 7psi but play it safe.

Front mount intercooler would help + a 3 inch turbo back exhaust will help with the flow.

As what Paulr33 has listed with suspension/drivetrain mods and don't forget your brakes, wheels and tyres.

APexi Power FC will come in handy with your Air/Fuel mixture and boost upgrade + get a dyno tune.

I have too disagree on keeping the standard turbo and agree with Roy. A HKS 2530 or a GTRS (or something along those lines) when set up properly is just as responsive as the stock one, if not more.

I am buying a hks2530 next week on the basis that i want to have response.I currently have 250rwhp with standard turbo,walbro fuel pump,front mount,11 psi, power fc.Have been told response from 2530 is even better than stock turbo.A bit sceptical about that but will let you know once it is installed and tuned.Main reason i am going for this turbo is for the fact that it will have stuff all lag and i can boost it to 16 psi without it blowing.

If you are on stock turbo and want response DON'T go for FMIC - use R34 SMIC. I went from stock to R34 SMIC to Hybrid FMIC and the change in mid-range response was noticeably negative when I went to FMIC. If you are running a larger turbo such as 2530 or GTRS than FMIC makes sense due to the higher flow required.

For response I'd run an electronic boost controller set to 11psi, a R34 SMIC, find an R34 turbo for a bit more flow, full 3" exhaust from turbo with metal cat, then get it tuned with Power FC. There is almost 200rwkw.

If you don't mind spending a bit more cash then put a GTRS and some cams into it (256 with a touch more lift) - 240rwkw.

Then focus on suspension and brakes.

Suspension:

Lower 1" (no more)

Dampers

urethane bushes

sway bars

pineapples

change tow to zero front and rear.

steering rack bushes

get rid of Hicas

check your rack ends and tie rod ends - replace it required

Rims:

18 x 8 +30

18 x 8.5 +30

Brakes:

recondition calipers

decent pads (street/track pads)

decent fluid - Dot 4

brake cylinders stopper

Chassis:

foam fill chassis rails and pillars

front strut brace (rear not required on R33/34)

take as much weight out as you dare

and then enjoy.

get some 4.4:1 diff gears (well 4.375:1 actually). get the 2530 like troy suggested, run a good boost controller to help bring it on as soon as possible. I'd run 18psi or so (if tuned well it shouldn't be a problem) get a power FC and have it tuned well. get an adjustable exhaust cam gear and have it tuned. get a metal intake pipe and ARC front mount with the shortest pipe run you can, or even an ARC sidemount cooler. nice cold air intake to the pod. don't get big nasty wheels, they will slow you down. some lightweight 16s or 17s with good tyres is plenty. don't get big brakes either, just some good pads, rotors and fluid in standard sizes will do it.

that should be good for 230 or so rwkw and be a fun, punchy set-up. no it won't be the mines GTR that everyone wanks over (which by the way is nothing that special), but it will be a nice street car to fang around in. :P

NO TURBO performance car should have a small smic with no airflow when you can cheaply have a neat fmic, especially if its a street car where you get very little airflow through the front of the car at sane street levels.

Ths smic have a 2-4psi pressure drop accross them , so any perceived gaing you are getting from less volume of piping you are losing in pressure drop accross the core meaning your turbo is running more boost then your inlet plenum sees and that just comounds the heat soak issue,

Sure the smic have their place....but i would never recommend a factory smic over a proper fmic setup. Especially when you want respons, so you want a nice cool and consistant inlet charge so you can get the ignition wound into the engine.

Ans i say go with a 2530Kai, far more responsive the GT-RS RB25 i drove.

Roy, dont suppose you have a dyno graph of a decently setup 2530 on a 25 do you? I'd be keen to compare it to mine. Obviously dyno graphs tell you shit all about how it drives on the street, but still i'd be interested. A mate of mine had a 2530kai on his and it supposibly went really well, however i dont see him often enough to ask for a dyno sheet.

Edited by PM-R33
If you are on stock turbo and want response DON'T go for FMIC - use R34 SMIC. I went from stock to R34 SMIC to Hybrid FMIC and the change in mid-range response was noticeably negative when I went to FMIC. If you are running a larger turbo such as 2530 or GTRS than FMIC makes sense due to the higher flow required.

For response I'd run an electronic boost controller set to 11psi, a R34 SMIC, find an R34 turbo for a bit more flow, full 3" exhaust from turbo with metal cat, then get it tuned with Power FC. There is almost 200rwkw.

If you don't mind spending a bit more cash then put a GTRS and some cams into it (256 with a touch more lift) - 240rwkw.

Then focus on suspension and brakes.

Suspension:

Lower 1" (no more)

Dampers

urethane bushes

sway bars

pineapples

change tow to zero front and rear.

steering rack bushes

get rid of Hicas

check your rack ends and tie rod ends - replace it required

Rims:

18 x 8 +30

18 x 8.5 +30

Brakes:

recondition calipers

decent pads (street/track pads)

decent fluid - Dot 4

brake cylinders stopper

Chassis:

foam fill chassis rails and pillars

front strut brace (rear not required on R33/34)

take as much weight out as you dare

and then enjoy.

The r34 smic is crap and heats soaks about 3 pulls (half a lap) after a r33 one, been there and tested them.... same diff when going from s13 to s15 smic...

aggressive tune (heaps and heaps of ignition timing, cant stress this enough)

standard turbo

normal FMIC

heavy duty clutch

some good tyres ($300+ each)

good suspension

pineapple kit

camber kit

castor kit

good cold air intake

good boost controller

consider 4.3 diff gears

fuel pump

good exhaust setup

tune the vct

thats probably it, no need for cams, cam gears, manifold, etc

my r33 has all of the above except diff gears and it runs great

has amazing response, great on fuel, excellent on the street

great for twisty roads etc, one thing my r33 doesnt have is new shocks, it has the standard ones still

here is mine in SAU garage

http://www.skylinesaustralia.com/forums/in...view&id=270

i meant its not exactly a mines setup, but its pretty quick for what it is

To be honest paul the vct is spot on and ANY change on the std turbo sends you backwards and as for timing it would be no more than any other tune an engine will only take so much regarless of turbo size....

Roy and Beer Baron are on the same path i would take HKS gt2530, 4.36 diff, Forward facing plenum (if big budget GTR ITB's) and GTR FMIC.

Edited by URAS

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