s15/which mods should i do first?

[stunny09]

Hey guys,

I really need some good advice I just got a JDM s15 specR silvia done 110kz, all its got is:

Greddy Front mounted Intercooler
Greddy Electronic boost controller
Turbo Timer
Full 2.5 Inch exhaust (some bodgy exhaust setup)
EVERYTHING ELSE IS STOCK AS A BLOCK

OK, so i want to do some mods asap, turbo is playing up and i dont like the lag ( it starts to die up top) should i throw away these mods and start fresh?
I dont know much about these cars so what do you guys recommend i do first (in order)?

This is just some upgrades off my head

Injectors, turbo, manifold,down pipe, hot pipe, cams, intercooler, oil cooler, suction intake, induction kit, larger afm,turbo outlet, racing fan pulleys


1.?????????????
2.?????????????
3.?????????????




And which turbo set up should i get ?
1) Little lag (anything BELOW 3000rpm of boost coming on is fine)
2) Won't die up top (Going strong till redline)
3) Not Snappy (vertical power on graph)
4) Will fit the stock position on an S15 (manifold, water/oil lines, dump pipe)
5) turbo set up under $4000 AND IF THATS TOO CHEAP FOR WHAT IM LOOKING FOR THEN HOW MUCH WOULD I NEED
6) AFTER IM DONE IM LOOKING FOR OVER 380hp (round 11-12sec 1/4 mile)

Thanks guys.........

 

[pegliobaglio]

There is a good guide of what parts you need per each stage of tuning here. http://forum.s15oc.com/showthread.ph...-advise-please
For that sort of power you will need an free flow air filter and z32 maf , 3" turbo back system and manifold,740cc injectors ,re circ valve,you already have fmic and boost controller so that's a good start, think the gt2871r is rated to 390 bhp and is what a lot of people use turbo wise as is very responsive and give good power through out the range.
Have a look at the chart should give you a good idea of what you need,don't forget to do the chassis too though,brakes will need upgrading really and I would be inclined to change the suspesion if that's stock too.

 

[stunny09]

Thank you mate, appreciate it nice to see someone that give ya a straight answer and doesn't laugh at ya lol

 

[pegliobaglio]

No problem mate, we all start out somewhere and the guys on here are very helpful!, I am just getting into all the tuning side of it myself as just finished with the rest of my set up ie brakes suspension arms etc. Now getting to the fun part!!!!!
Just realised the link doesn't seem to work.
So have copied all the info for you give you an idea...
This is just a general guide for what mods are required for boost upgrades. People have different opinions about this, but If you stick to this guide you should be ok.
This does not take into consideration essential things like suspension, brakes and clutch improvements that will be required at an early stage.

Standard - 0.7bar boost, 250PS
Curb weight 1200–1270 kg

Stage1 - 260-280bhp
Free flow air filter
Free flow exhaust
Uprated fuel pump
Boost controller to achieve 0.9 bar boost pressure
Cooler spark plugs
Super unleaded fuel
Custom ECU remap

Stage 1a - 270-290bhp
Free flow air filter
Free flow exhaust
Uprated fuel pump
Boost controller to achieve 1.0-1.1 boost pressure
Front mount intercooler
Cooler spark plugs
Super unleaded fuel
Custom ECU remap

Stage 2 - 280-300bhp
Free flow air filter
Free flow exhaust
Uprated fuel pump
Boost controller to acheive 1.1-1.2 bar boost pressure
Front mount intercooler
Cooler spark plugs
Super unleaded fuel
Custom ECU remap

Stage 2a - 290-310bhp
Free flow air filter
Free flow exhaust
Uprated fuel pump
Boost controller to acheive 1.2-1.3 bar boost pressure
Front mount intercooler
Tubular manifold and uprated turbo elbow
Uprated dump valve
Cooler spark plugs
Super unleaded fuel
Custom ECU remap

Stage 3 - 310-330bhp
Free flow air filter
Free flow exhaust
Uprated fuel pump
Boost controller to acheive 1.2-1.4 bar boost pressure
Front mount intercooler
Tubular manifold and uprated turbo elbow
Nismo 555cc/740cc injectors
Z32 AFM
GT28RS or GT2871r turbo
Uprated dump valve
Cooler spark plugs
Super unleaded fuel
Custom ECU remap

Stage 3a - 340-360bhp
Free flow air filter
Free flow exhaust
Uprated fuel pump
Boost controller to acheive 1.3-1.4 bar boost pressure
Front mount intercooler
Tubular manifold and uprated turbo elbow
Nismo 555cc/740cc injectors
Z32 AFM
GT2871R turbo
Uprated dump valve
Cooler spark plugs
Super unleaded fuel
Custom ECU remap


Stages beyond this will require internal head and bottom end work too.

 

[DeanS15]

^^this is all good advice . as you go through the tuning of the engine, make sure the chassis is sorted enough to keep it safe. stock brakes are crap for starters, coilover suspension, anti roll bars etc will all help to plant the car better and good handling and braking will make the car quicker - which is the goal isn't it

 

[Hypnotik]

Hmm... I wonder what stage I'm at? 4? lol.

I'd do all your maintenance first to get a good starting point that way you're not chasing your tail later. All filters(oil, fuel, etc), all fluids(brake, oil, trans/diff oil, etc), tires, etc.

Then I'd do your supporting mods. Fuel pump/injectors, clutch, programmable ECU, possibly even brakes and transmission.

After all that I'd worry about upgrading your turbo.

 

[steve_fctuning]

If your looking for around the 380-400hp mark.. then the factory block will be fine.. its just your gearbox will be thinking mmmmm so its a matter of how your style of driving is.. For ULTRA reliability really swap to an RB box (as its stronger and will be overall more reliable) but I don't know of THAT many S15 boxes that drop a cog personally but then there arnt as many S15 floating around as 5 speed S14's

Turbo wise you gotta good choice for the SR for the street, so to speak

The common ball bearing Garret GT2871 (86 housing) will see you with 380-400hp at the crank (320-340whp)
The TD05 18G is also another GREAT unit that will probably respond a tad better and give a REALLY hard pull and give similar power
The HKS GT-RS - Great unit but slightly more (as it uses a slightly different design on the compressor - great spool)
Old Skool T3/T4 but more laggy as the design is older but upgrade wise its cheaper to swap out compressor and exhaust housings
The Borg Warner S256 (my personal fav and not bad spool for a journal bearing) which will give you a solid 400whp on an SR (around 450 + ) but naturally you just run lesser boost but its with a few to future internal forged upgrades - it makes full boost a little later but the torque band spread is luuuurvely and it PULLS HARD!! (its more equalled to a GT30 really)
Then there's the likes of the Precision series also...

Fuel - use 740's/850's and Z32 MAF

and then like the guys mentioned.. make it stop with good brakes, suspension and tyres of course

ECU wise you have your good ol factory ECU with your basic features as well as Aftermarket common units such as Plug n Play PowerFC D Jetro (go MAFless) or more upmarket and advanced, Haltech units (which you in Aussie can get hold of VERY easily)

Fuel pump - bosch 044 is my preferred but Walbro drop in is nice n easy n cheaper and designed for intank.. The bosch involved some minor modification


Steve

 

[stunny09]

Gday steve,

Your a ledgend mate this forum when comes down to advice is the best forum by far thanks dude

Thanks everyone for the great advice appreciate it When im done ill let you guys know how i i go

 

[stunny09]

Hey steve,

When you say
Fuel - use 740's/850's what you mean by this ?

 

[Hypnotik]

Injector size, 740cc or 850cc. Stock is 370cc and won't support much more power than the stock turbo.

 

[LuPix_S15]

You got some great advice there mate and as Chris said we all start from somewhere


I can't recommend Ferodo DS2500's brake pads enough - the ultimate compromise between fast road and track use. The bite is a world apart from stock pads. Even with stock discs you'll feel the immense benefit and coupled with braided lines and higher DOT brake fluid you're onto a winner :thumbs:

Upgrading front tension rods plus checking the balljoints for lower arm + tie rod ends (replace if there's play in these) will also give you back a lot more feel/response in the steering...

 

[sliding-r]

Injector size, 740cc or 850cc. Stock is 370cc and won't support much more power than the stock turbo.

Spec R comes with 440 doesnt it?

have u the ADM version?

 

[AllanOrr]

Yea dude the JDM Spec R came with 440cc Injectors This is why all the S14/S14a guys will snap these up as a cheap upgrade for around £100-£120ish

 

[ibizatom]

Very interesting thread!

Nice to see people suggesting mods that are not power related compared to VAG cars where everyone says Remap first. lol. Yes you gain 50bhp and around 50 torques from £300 but with standard brakes, your pushing them to the limits!

 

[AllanOrr]

I work for VW and I have to say I cant stand the customer base it has when people come in with tuned cars because they cant see past as you said Remap Remap Remap, Toyota was a better place :wack:
Its always the same with every car though if you put more power in you are going to need to replace the main things in time as James said Brakes are always over looked by some people

 

[ibizatom]

lol.

Very true though. The S15 is a totally different animal to my Seat Ibiza. Just on other forums elsewhere people always talk about power first before of thinking about more important stuff like brakes, suspension, and now after reading this thread, the other list of stuff before you even think about adding more power.

Lots of bed time reading for me I think.

 

[AllanOrr]

Honestly dude the limmits are endless on these cars and if you do manage to max out a SR20det then you can always just drop say a RB26, 2JZ or a nice v8 what ever takes you fancey :wack: lol
Its good to see the list on page1 with the different changes what power you should look to get

 

[pegliobaglio]

I think with any car its always A good ideA to get a nice solid base first and then up the power,first thing I did to my car was change all the fluids,new plugs and filters then changed my diff(had a 2 way) added arb's ,fully adjustable suspension arms and brakes,had the allignment done and just got used to driving the car as they are pretty quick and can be quite twitchy from standard have seen so many people bin these cars within the first weeks of ownership. So thought I would do the base first then start upping the power,don't really see the point in having a car with 400 bhp if you can't really use it as the rest of the car isn't set up to take it.
You will always get good advice on this site mate!

 

[ibizatom]

Honestly dude the limmits are endless on these cars and if you do manage to max out a SR20det then you can always just drop say a RB26, 2JZ or a nice v8 what ever takes you fancey :wack: lol
Its good to see the list on page1 with the different changes what power you should look to get

lol.

Defiantly. I always like to read up and what gets you what. Compare this and that.

I think with any car its always A good ideA to get a nice solid base first and then up the power,first thing I did to my car was change all the fluids,new plugs and filters then changed my diff(had a 2 way) added arb's ,fully adjustable suspension arms and brakes,had the allignment done and just got used to driving the car as they are pretty quick and can be quite twitchy from standard have seen so many people bin these cars within the first weeks of ownership. So thought I would do the base first then start upping the power,don't really see the point in having a car with 400 bhp if you can't really use it as the rest of the car isn't set up to take it.
You will always get good advice on this site mate!

Couldn't agree more!

I had a MK1 1.8 focus before getting the Seat Ibiza tuned to 250bhp. Boy that was a shock to the system. lol.

Also, I have never driven a RWD car so tbh, power is way off the cards till I get used to the car. I also plan to get some RWD lessons to learn how to control the car just incase. Might seem a little silly to some but I don't fancy causing any damage to the car. Spend too much of my life around my car as it is. lol.


I feel I may have hijacked the thread somewhat? lol

 

[AllanOrr]

dont be silly mate again another point that would be over looked on this you put 350bhp through your engine and dont do anything about the suspension your going to be in trouble,

I dont some lets say "naughty" sessions with one of my mates that has a R33 GTST running around the same as my S15 at the time keeping in mine the Spec R as a faster spooling turbo and I also had a decat but other than that was totaly stock, but when it came to drifting I had that much bodyroll and because of the diff I found it quite had to mainly keep the car in a long slide, where as on the skyline because it had the suspension changed he could do rings round me, need to remember it isnt all about chasing BHP figures here, a car set up to drift will not be as fast as a car with a time attack set up
myself personaly...lots of noise and smoke :wack: