My First Serious Mods On R33 Gtst

[sl33py]

I've got a stock R33 GTST SII (97). Had it two years now, all she's got is 3" exhaust from the turbo back, drop in K&N panel and Splitfires to replace the stock coils which were arcing badly. It pulls ~150rwkw on the dyno.

Decided I wanna upgrade, with these considerations:

1) Stealth. I don't want heaps of attention

2) Reliability. This is my daily, so I need it to run every day without fail

3) Driveability. It can't be a horses a55 in traffic or temperamental in cold Canberra weather

4) Future proofing for other possible mods (mainly by using an ECU instead of a bleed valve)

5) Hopefully without completely killing my mileage. I currently use about 13-15L/100 with only 150rwkw regardless of how I drive, but I've heard of heaps of ppl with nearly double my power getting the same or only slightly worse mileage.

I'll have the work professionally done. I've seen the dyno charts on here, read what I can, found a local mechanic I like, and he's recommended the following, which pretty much agree with, I'm just after a few other's opinions/pointers/gotcha's:

1) Microtech LTX12S ECU because my mechanic is most familiar with the newest units (he refused to use the old ones).. This will let me make whatever upgrades I like later on (futureproofing).

2) HKS GTRS2530. This is apparently a relatively simple swap from stock without too much buggering about, and can keep the original heatshield, which I like for discretion.

3) FMIC, I think it will be the Trust M-Type and painted black.

4) Possibly replacing some of the air intake piping with metal because he says the stock plastic expands and changes the performance characteristics for the worse. Plus he says metal will keep the air cooler. We haven't decided whether I need to do that or use a CAI or whatever, as he wants to leave it until the time to see what gains it will give and whether it's worth it.

5) Fuel pump.

6) Fuel regulator.

He says on a very safe tune he should get 240-260rwkw out of it. Would you say this sounds right for a safe tune? What would a harder tune give?

Someone told me that the stock injectors won't do well/give more than 220rwkw, but the mechanic says he's got 4 or 5 R33's on stock injectors with ~300rwkw. I'm not sure about boost levels or anything else, I forgot to ask him... I'm also pretty sure I'll be keeping the stock plumb-back.

Is there anything else I should know, have left out, or not thought of, e.g. supporting mods like the fuel pump? I want to make sure I make the right decisions if I'm gonna throw a bunch of money at it.

BTW, the car will soon have a clutch good for 300kw and it's already lowered an inch or so (not 'dumped').

Edited March 14, 2007 by sl33py

[R33GOD]

if u want to keep it stealthy run a r34 smic and hiflowed turbo boost to about 14-15 psi with the supporting mods you have. no point in painting the fmic black as it will attract more heat. run a nismo fuel regulator and run injectors on whatever duty cycle u want...u gonna need a better fuel pump too. get the turbo back exhaust with a hiflowed cat and u should see yourself with around 220rwk.. just my opinion if u want to keep it lookin stock

cheers

[sl33py]

Damn, I have 3" turbo back, screwed up in the first post (fixed).

Is that the stock GTR IC? Does it work the same or better than a Trust IC? I'll have to ask the mechanic what he thinks about it, thanks for the idea. Painting an IC will really attract heat? He didn't say anything about it when I suggested painting it... Again will have to ask. What do others think?

Thanks for the suggestions. I was looking into hi-flowing the stock turbo but the mechanic said he is against hi-flow turbos cos the one he recommends is easy enough to fit, and according to him will perform much better for the money you pay ($1900 is about the best for a hiflow around here, he said the turbo is about $2500 to me, much of a muchness).

@ fuel regulator, yeah he mentioned that but I forgot to include it in the list. From what you said, it sounds like a fuel regulator eliminite the need for new injectors, is that right?

Got the fuel pump on the list.

[ProphetR33]

Damn, I have 3" turbo back, screwed up in the first post (fixed).

Is that the stock GTR IC? Does it work the same or better than a Trust IC? I'll have to ask the mechanic what he thinks about it, thanks for the idea. Painting an IC will really attract heat? He didn't say anything about it when I suggested painting it... Again will have to ask. What do others think?

Thanks for the suggestions. I was looking into hi-flowing the stock turbo but the mechanic said he is against hi-flow turbos cos the one he recommends is easy enough to fit, and according to him will perform much better for the money you pay ($1900 is about the best for a hiflow around here, he said the turbo is about $2500 to me, much of a muchness).

@ fuel regulator, yeah he mentioned that but I forgot to include it in the list. From what you said, it sounds like a fuel regulator eliminite the need for new injectors, is that right?

Got the fuel pump on the list.

Painting your intercooler won't make much of a difference to heat, there has been many well publicised tests stating the difference in intake heat is negligible. Just make sure when painting it you use radiator paint (has better heat dispersion characteristics than regular paint) and when spraying do not spray directly onto the intercooler, spray across the intercooler with very light coats (this avoids clogging up the intercooler core with excess paint). The R34 GTT cooler has a bigger surface area and thus more efficient than the R33, you'll have less lag, but if you're going for higher horsepower then the front mount is the only way to go.

[R33GOD]

Damn, I have 3" turbo back, screwed up in the first post (fixed).

Is that the stock GTR IC? Does it work the same or better than a Trust IC? I'll have to ask the mechanic what he thinks about it, thanks for the idea. Painting an IC will really attract heat? He didn't say anything about it when I suggested painting it... Again will have to ask. What do others think?

Thanks for the suggestions. I was looking into hi-flowing the stock turbo but the mechanic said he is against hi-flow turbos cos the one he recommends is easy enough to fit, and according to him will perform much better for the money you pay ($1900 is about the best for a hiflow around here, he said the turbo is about $2500 to me, much of a muchness).

@ fuel regulator, yeah he mentioned that but I forgot to include it in the list. From what you said, it sounds like a fuel regulator eliminite the need for new injectors, is that right?

Got the fuel pump on the list.

correct about the injectors. theres nothing wrong with hiflowing a stock turbo, there done with prescision. depending who u get it from. ask slide in the forum. i been told not to paint the cooler as it attracts heat. the r34 smic fits straight in where ur factory one goes into. i would look into it if i were you and save some money in the process

[sl33py]

Rightio, will do.

Also, I'm hoping for a fair bit more power than 220atw. Hoping more like 250. Now I've got more options on the IC, need to read more on CAI as I like the idea a lot more than a SRI just gulping in warm engine air...

[Black_Widow34]

u will need new injectors... the stock ones run out of steam at about 200 - 210 rwkw.. u will need a better clutch once u go past 200rwkw... i would go with the apexi power fc as its an easier/cheaper install and will support all the mods u will do in the future... this is what i would suggest:

-modify the stock intake to suck more air in from the side (like the gtr intake)

-turn up boost to about 12 -13 psi (i think that is pretty safe on the stock r33 turbo - check on the forum to make sure)

-power fc (with tune)

these mods should get u close to the 200rwkw ballpark... once u done these u will need the cluch and injectors...

- intercooler + turbo - if u are going to hi flow the stock turbo u will retain the stock resopnse (less lag) but it will max at 250 - 270 rwkw... if u want more power u will have u sacrifice bit of response and go for a bigger turbo... it depends on how far u want to go.. also remember it is not recommended to run stock internals over 270 - 280rwkw if u want5 to play it safe...

also 250 - 270rwkw is a lot for a daily driver and most ppl are happy with that...

[Steve]

GTRS2530? you mean GTRS? the 2530 would be a bit small

for around 240+rwkw, replace your injectors, fuel pump and FPR. So many Rb25s go pop with that sort of power on stock injectors

you will need to up grade your clutch (if its manual)

For many hours of safe thrashing pleasure, dont go over 1.2 bar - keep the rev limit to around 8K rpm (above 8200rpm is very dangerous on stock head)

front mount will be heaps better than side mount cooler for that sort of power.

a split dump would be a good thing

get a decent ebc

The intake pipe from afm to turbo has heavy guage wire reinforcing, it wont collapse like RB20 do, doesnt hurt to change them, but not essential.

fit a pod, do the right thing and sheild it plus CAI, otherwise it would be a step backwards imo. (apexi pods cost $98 form a sponsor on ns.com, bolt straight up and flow very well - as well as clean well)

[Guilt-Toy]

forget the microtech mate. get a PFC. there are still a few around.

[sl33py]

I read the PFC is good and started looking around for ppl to do it, but locally, the guy who is considered the best with PFC has rooted a few cars now and I've heard a few too many horror stories to take it there. I'm just doing what the general concensus was as far as ECU's: go with what your tuner recommends. I asked him if he can work with the PFC and explained the bad stories I'd heard about MC (ie bad economy and only good for WOT power, bad cold starts etc ect) and he said he knows the Microtech, and that he agrees the old ones were 5h1t, but that they've come leaps and bounds and he likes to work with them.

The clutch is soon to be replaced with one rated for 300kw (have to check if that's rw or fly).

the 2530 would be a bit small

He said for what a hiflow would cost me, he'd recommend a new turbo. I looked up on the HKS site - the GTRS2530 is rated for 320PS, which is about 235KW (dividing by ~1.36). Correct me if I'm wrong, but doesn't that that mean it won't go above 235KW no matter other engine parts it's combined with... and is this why you say it's a bit small? What would you recommend instead (bearing in mind I don't want it sticking out like dogsballs, I hope to fit it under the stock heat shield, or at least a stockish-looking custom heatshield).

This mechanic says he has several R33's running around town on stock injectors doing 300rwkw. I've heard arguments for and against this now, and need to discuss this with him further as I don't know enough to argue one way or the other myself.

I was under the impression that the Microtech will be able to control boost electronically, but with PFC you need to add the boost kit. Also, with the PFC you need to add to Z32 meters (or similar) which cost. The Microtech apparently doesn't need any of that.

Sounds like if I want to futureproof, I should go the FMIC, as if the above comments are correct, the SMIC will be limiting later if I want more power.

While it will be a daily driver for now (say next 2 years), I definitely don't want to buy or do anything which will just need to be ripped out later. I've just had to replace the clutch (needed it and was in a bind) and now finding I'll need it again cos the clutch they gave me won't handle this kinda power, and I definitely want to avoid that kinda unnecessary spending in the future :|

I like the idea of a shielded pod/similar filter (this mech recommend JR filters), and will discuss CAI with him.

Thanks for the pointers so far. That comment about the turbo being too small has me concerned WRT my aims (to be honest, I really want 250rwkw).

Edited March 14, 2007 by sl33py

[Steve]

370cc injectors are good for approx 370bhp, i.e. for every cc of an injector on a 6 cylinder car, it will support approximately 1hp at the FLYWHEEL

I have seen many engines popped because people want to save money on injectors, end result, they buy a new engine, have to swap it AND upgrade their injectors. do it right the first time

When you see a rating of a turbo, you must consider any other mods that have been included to make the power. The figure may be a little conservative, but the figure is a 'best case' scenario. It is much better to buy a turbo that will comfortably make the power you want, and have a bit more for later (if you want more) than to buy a turbo that will 'just' make the power you want in an ideal world. My 0.02c anyways

The GTRS is ideal for the power you are chasing, can be stretched into the high 200s, and will fit in the factory spot no problems.

[sl33py]

Thanks Steve, I'll mention that calculation when I ask the mech and see what he says. I don't want anything blowing up!

Yeah... what your saying makes sense RE power. I don't see how an engine can make any more power overall than the turbo is rated for.

On this site, I can't see the GTRS model. http://www.hksusa.com/products/?id=706 Please note, I've only linked directly to a specific turbo, as in this view, it lists the available turbos down the left. But if you go to the comparison chart though, you CAN see the GTRS. wtf...

Interestingly, the GTRS is rated for 400PS: I assume thats at the fly, and 400PS = ~294kw. And that comes down to about 220rwkw (x75% which I've found works well in general)... Still noticably short of what I want.. can you explain how this turbo would be good enough? Maybe I'm calculating wrong.

Edited March 14, 2007 by sl33py

[Black_Widow34]

I read the PFC is good and started looking around for ppl to do it, but locally, the guy who is considered the best with PFC has rooted a few cars now and I've heard a few too many horror stories to take it there. I'm just doing what the general concensus was as far as ECU's: go with what your tuner recommends. I asked him if he can work with the PFC and explained the bad stories I'd heard about MC (ie bad economy and only good for WOT power, bad cold starts etc ect) and he said he knows the Microtech, and that he agrees the old ones were 5h1t, but that they've come leaps and bounds and he likes to work with them.

The clutch is soon to be replaced with one rated for 300kw (have to check if that's rw or fly).

He said for what a hiflow would cost me, he'd recommend a new turbo. I looked up on the HKS site - the GTRS2530 is rated for 320PS, which is about 235KW (dividing by ~1.36). Correct me if I'm wrong, but doesn't that that mean it won't go above 235KW no matter other engine parts it's combined with... and is this why you say it's a bit small? What would you recommend instead (bearing in mind I don't want it sticking out like dogsballs, I hope to fit it under the stock heat shield, or at least a stockish-looking custom heatshield).

This mechanic says he has several R33's running around town on stock injectors doing 300rwkw. I've heard arguments for and against this now, and need to discuss this with him further as I don't know enough to argue one way or the other myself.

I was under the impression that the Microtech will be able to control boost electronically, but with PFC you need to add the boost kit. Also, with the PFC you need to add to Z32 meters (or similar) which cost. The Microtech apparently doesn't need any of that.

Sounds like if I want to futureproof, I should go the FMIC, as if the above comments are correct, the SMIC will be limiting later if I want more power.

While it will be a daily driver for now (say next 2 years), I definitely don't want to buy or do anything which will just need to be ripped out later. I've just had to replace the clutch (needed it and was in a bind) and now finding I'll need it again cos the clutch they gave me won't handle this kinda power, and I definitely want to avoid that kinda unnecessary spending in the future :|

I like the idea of a shielded pod/similar filter (this mech recommend JR filters), and will discuss CAI with him.

Thanks for the pointers so far. That comment about the turbo being too small has me concerned WRT my aims (to be honest, I really want 250rwkw).

300rwkw on stock injectors? i dont really think that is possible unless u crank the fuel pressure up to stupid pressures and even then it wont be long untill u can kiss ur motor goodbye... its ur choice $800 on injectors or $7000 (with labor) for new engine...

[sl33py]

I'll ask the mech!

Would these be side injectors or top ones that you're talking about?

I think we discussed injectors (hence why he said he's got 300rwkw on stock) and he said that if you replace the injectors, it's best to make them the 'top' kind... I assume this stuff don't look so stock Doesn't matter really - if it's going to save the engine, I'll get it, or ask him to check up on it.

[ferni]

2530 is too small for 250rwkw, expect around 200-210rwkw, 2535 will give around 230rwkw.... Injectors start to be the limit around this power give or take a touch...

I'd be worried giving my car to a mechanic who thinks he can get 300rwkw out of stock RB25 injectors.... Or maybe he has a happy dyno that reads about 50rwkw to high.

I also think once you start going over 250rwkw or so you're going to run into reliabilty problems, going off your first post, and your priorities, i'd stick with the 2530 or 2535, stock injectors and a safe tune, which will give you a very nice 210-230rwkw (or more if his dyno reads high?)... very usable.

[sl33py]

I also think once you start going over 250rwkw or so you're going to run into reliabilty problems, going off your first post, and your priorities, i'd stick with the 2530 or 2535, stock injectors and a safe tune, which will give you a very nice 210-230rwkw (or more if his dyno reads high?)... very usable.

Weird.. the mech said he can get 240-260kw from a 2530...

So.... what if I had the money and want reliability etc AND want 250rwkw or so? What would I need to do. Enough work with the right parts and 250 should be reliable, right?

I won't really know what to do if the mech says 'that's all horsecr4p' about what's been said on here He seems very well respected locally, so makes me think he can't be too wrong...

Also, can someone explain how my calculations were wrong so I can figure out what PS I need from a HKS turbo. Grr more I learn the less I know

Edited March 14, 2007 by sl33py

[Steve]

The GTRS will comfortably support 250rwkw - this is real world, repeatable power on RB25. it has made up to around 300rwkw, that may be on a generous dyno though, but if you want 250rwkw, the 2530 is too small

250rwkw is an easy ask from a internally stock RB25 BUT do it safely, I made over 320rwkw with a stock engine, and it never skipped a beat (did do head gasket though). There are several others on here that have done the same, not to mention the dozens in japan.

I agree with Black_Widow34, it may be time to look for a new mechanic if he is telling you he can get the sort of power he is quoting out of stock injectors?

here is a link to an injector calculator http://www.rceng.com/technical.htm#WORKSHEET whilst I dont always thing theory is perfect in the real world, it does give an indication of what you can expect

and FYI, nissan base fuel pressure is 2.55kg, most aftermarket injectors are rated at 3.0kg - so use these figures to get a guide as to what you will acheive with upgraded injectors

remeber these figures are for FLYWHEEL, not rear wheel

but the bottom line is, if you are going to believe/trust your mechanic, why are you asking these questions on here?

and if you are going to believe us, why are you asking your mechanic?

I really do think its time to find a different mechanic if you dont trust him, but that's me

[sl33py]

Well I trust this guy a lot more than the other choice I have. And he's only referred to real results he's had so far and everyone around here thinks he's good. Just wanted to check if there was anything I'd forgotten about or should budget for (eg fuel pump, hadn't thought of that), and then the whole turbo thing came up, which sorta made me wonder.

Will ask him what he reckons about this stuff and see what he says, I'll most likely go with what he recommends, tempered by info gathered off here. EG the 2535 sounds better for me than the 2530.

BTW how do I convery 3.0kg to PSIG? (or is that the wrong number in the wrong place)

Edited March 14, 2007 by sl33py

[Steve]

kg to psi, multipy by 14.5

[sl33py]

OK so in the Fuel Injector Worksheet I chucked in (top to bottom): 340, 6, 0.6, 0.5 and 37 (2.55x14.5) and got 73.73lb/hr and 775cc/min. Sounds a lot higher than the stock 330ish Hope I got that right. Interesting..