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Hi, just a question to all the people who have a garrett gt3540 on their rb25. please post up what you have done to your engine and mods. and the power you are making at what boost.

Im soon taking the step of putting one onto my car and im interested to know how everyone elses goes.

Thanks

David

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Unless you are prepared to go to a lot of trouble and expense with mods you are throwing gold bricks at a pig. I will be using a 35/40 as well but I will have a full supporting mod list to go with it. Major head porting, cams, big fuel etc.

From the homework I have done if you only have minimum mods you will simply turn your car in to a lag rat that will eventually give you the shits because your power hit will be so far up the rev range.

Its a lot of money to get it wrong. Ask a lot more questions before you go ahead.

probably better to research the forced induction section or post this in there and see what response you get, but Noels right. Unless you have a built engine it's a big turbo that will have to run low boost to produce low numbers at high revs.

Well im taking the setup off my friends car. i am willing to put the $$ into the engine because this is what i want. my question was how much power peopel get out of their car with the 3540. and mods like size of injectors etc etc etc.

I have driven a stock motor with just the turbo, and i agree it was a little laggy but when it came onto boost i really liked how it went. im planning on putting on the turbo while i save up for a rebuild.

So good results on a stock motor are impossible with this turbo? Is that what your suggesting, FinLine?

It's definately not impossible, but I think you have to agree Adrian that unless you have intentions of doing something with the motor down the track there are more suitable turbo upgrades for a stock motor?

I have driven a stock motor with just the turbo, and i agree it was a little laggy but when it came onto boost i really liked how it went. im planning on putting on the turbo while i save up for a rebuild.

In that case I suppose it's not such a bad idea, but i'd be tuning the car well, keeping rev limiter low and keeping the boost down so that you don't risk your motor letting go before you want to do the rebuild, otherwise you'll be without a car.

Well im taking the setup off my friends car. i am willing to put the $$ into the engine because this is what i want. my question was how much power peopel get out of their car with the 3540. and mods like size of injectors etc etc etc.

First things first. Do you have a built bottom end. The type of power we are talking here will soon destroy you engine unless it has been fully prepped with good rods, forged pistons, updated oiling system, crank ring, good rod bolts, balncing etc etc.

There may be easier routes to take but here is a list of what I deemed necessary to make the type of power we are talking.

Bottom end.Reground and cryoed crank machine for a crank collar. Eagle forged rods with arp rod bolts. ACL race bearings. Forged pistons of a reputable brand. (oil squierter notched) The whole assembly balanced to within an inch of its life for high rev application. Modified sump, Gated and baffled, Jun oil pump. Tomei oil restrictors. Lightened flywheel. Tuffman harmonic balancer.

Cylinder head, major porting, Conversion to solid lifter valve train, stronger valve springs, New guides. arp head stud kit, steel head gasket. Hi lift solid cams and adjustable cam gears.

Fuel delivery. larger fuel pumps, dual feed fuel rail, fuel reg, 750cc injectors, Greddy Plenum, q45 throttle body, Garret 35/40 ex gate turbo.

Supporting mods. larger exhaust from the turbo back, (31/2 inch. larger intake pipe. q45 afm, Good quality gate and bov. Large front mount. external oil cooler. stronger timing belt. Cold air intake. Splitfire coil pak.

Then theres all the other shit. A new and stronger clutch will be an absolute necessity. the gear box will need an over haul and the first three gears will be strenthened at the same time. Little things like uni joints wheel bearings etc will have to be in first rate condition or failure is a given. An after market ecu is also on the list along with a boost controller.

Estimated power output will be in the upper 300 to early 400rwkw range.

Do your homework son. One of the first things that struck me when I started my skyline journey was the amount of young dudes who thought it was all about throwing on a bigger turbo and goin out to make hay. It doesnt work that way. For every action there is a reaction and in this case the reaction is a litany of broken parts hearts and busted wallets.

Go look in the classifieds, There is a brand new engine there built for this type of application going cheap for around 18,ooo bucks. That should give you some idea of whats required to do it properly.

To my way of thinking the best bang for buck is still the hiflow standard turbo with a good fuel pump, injectors and supporting mods. Lazy bastards car is such a machine and just impresses the sox off me with its performance for bucks. Runs mid 12's at the drags and pulls like a bull in springtime.

Your car, your money, do what you will, but just dont start without truly knowing how far down the tunnel the end really is.

I think the matter of this was to ascertain what mods people have with this type of setup and what power is being produced with it, not the "should i, shouldnt i" scenario, although the provide information that people have placed here is a good starting point which could have easily been researched through the FI section of this forum. He was only trying to gather what "POWER" is able to be made out of the setup.

The turbo itself is rated at around the 700ps value or good enough for about 400+ rwkws with the right setup in mind to go with it, hence this turbo is best suited to a 25 or 26/30 hybrid engine for proper benefits to be held. Your best bet is to check the FI dyno results to gather a better opinion on power to mods ratio, rather than ask as the flaming that people get is always going to be there no matter what.

Also best bet on a side note is to get this topic moved into the FI area as its more specific to that are than the QLD section of the forums,

Plus note "....just a question to all the people who have a garrett gt3540 on their rb25 "

Good luck with that

Cheers

A

Oops forgot one thing power will also be determined by the a/r on the exhaust side of the turbo ie: .63 .68 etc this will also be the determining factor of LAG, as well as depending on internal or external gate. :P

Thanks for the reply there fineline. I have the splitfires, ecu, injectors, reg, gate, bov, fmic, new afm, timing belt etc etc etc. im not yet aiming to get big hp figures just yet, until i get my rebuild done. so im willing to put up with the lag and poor response until i get some better internals. As im not the richest pimp in the world but more than eager to do it.

Thanks for the reply there fineline. I have the splitfires, ecu, injectors, reg, gate, bov, fmic, new afm, timing belt etc etc etc. im not yet aiming to get big hp figures just yet, until i get my rebuild done. so im willing to put up with the lag and poor response until i get some better internals. As im not the richest pimp in the world but more than eager to do it.

Go for it bud. As long as you have an understanding of where it will lead then more power to you. Hope to see you at the drags or similar one day.

Iam running a Gt 35 40 turbo with 1.15 a/r housing, which pumps out about 320rwkw.

But it still runs standard cams and can still run more boost so there is room for improvement, but the traction is the issue at the moment.

If you're concerned about lag, get the .63 rear housing. Saying that you need engine internals and other modifications other than the obvious is simply untrue. Stop filling people's minds with shit.

No doubt you are the type that would put an 850 double pumper holley on a 186 holden and just jet it down to get it to run just so you could say you had one.

The only shit I see here is from you suggesting that a 35/40 is the right way to go for a relatively standard rb 25. Perhaps with a 100 hp nos shot it may be just fine but as a stand alone entity how do you propose he eliminates the lag?

I have an 0.82 rear housing with an external gate. If i was so worried about lag i would have got a supercharger. and im willing to put up with the lag for now, i know what its like with the 3540 and im willing to put up with it until i can scratch up more cash for stronger internals. I am only aiming for about 300hp for now or whatever is safe until i get the engine sorted.

I want to take it to track days etc from now too because i just got my licence back after a lesson learned. thats when i get some decent power out of it. muahahah

No doubt you are the type that would put an 850 double pumper holley on a 186 holden and just jet it down to get it to run just so you could say you had one.

The only shit I see here is from you suggesting that a 35/40 is the right way to go for a relatively standard rb 25. Perhaps with a 100 hp nos shot it may be just fine but as a stand alone entity how do you propose he eliminates the lag?

No champ, I'm the kind of person who actually HAS a GT35 on a stock RB25. I've been there and done that mate. I'm not pulling info out of my arse like yourself - I've done it. I've already said how he should get around the lag issue. If your eyes weren't painted on you'd see that in my last post.

I've had a 3037s on a standard (bottom end) rb25 with cams, greddy plenum etc etc which ran with no issues for quite some time at 380hp at 1bar. However once I started pushing the boundries of 1.2bar, the bottom end did let go and it punched a rod out the bottom of the block. My suggestion, and it comes from experience, is don't push too hard on your stock bottom end or you will see dissaster. Also cams will easily aid you in your quest for earlier power. Like adrian said if you want earlier boost get a smaller ex housing, however it seems as though you arleady have the turbo and some other gear. All I can say is good luck, take it easy and save up for supporting mods because once you get 300hp you'll want more.

M.

No champ, I'm the kind of person who actually HAS a GT35 on a stock RB25. I've been there and done that mate. I'm not pulling info out of my arse like yourself - I've done it. I've already said how he should get around the lag issue. If your eyes weren't painted on you'd see that in my last post.

And if you paid attention instead of looking at my arse to see where the info comes from you would have noticed that he has a .82 housing. He has also stated that he cant be arsed about lag so I guess its all moot. :D

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