Gt3540r Iw On Its Way R33 Gtst

[discopotato03]

Hint : To have less exhaust manifold pressure the leading edge is twin scroll housings and unfortunately the external gate . This is the route to having performance and turbine response without the excessive exhaust restriction and heat . I would do this rather than open up a healthy engine even one with 9:1 static CR .

People the world over are blown away by how well this this system works even with bigish turbos .

If it were me I'd think about the HKS low cast manifold/ext gate and a twin scroll turbine housing for the GT3582R . Up to you but having an engine that pulls well from 4500 to 7500 is a little narrow for a road car in my book . If you can pull some extra torque up (notice I didn't say boost) the extra 500-1000 usable revs makes a huge difference . These bits cost more than walking around money but compared to a serious engine rebuild with upgraded components its cheap for the result .

My opinion only but yes the real GT3071R's and GT3076R's (pref 52T) would have been further up my wish list .

Your calls , cheers A .

[bazr33]

i was going with this turbo as its rated at around 700hp, and if later on i decide to put more boost through it and go past 350rwkw then it will handle it.

I didnt want a turbo like a hiflow or something a little bit bigger and run it on its max effiency everywhere i went. (even though i'll only be pushin minimal boost on the street half of the time)

I'll see how i go with the stock internals for now, but i will buy upgraded internal parts as i go. and if it does blow or dont like it, or decide to run more boost, i'll be right.

originally i was looking at the 3071, but i have noticed a couple of ppl only seeing 240rwkw- 270rwkw, i dont know if it was the setup they had or what.

But looking at the amount of ppl with the gt3540 and they are seein 300rwkw plus, i was like ahhhh yes. Yes lag will be an issue but i will deal with it. And the other good point is that they are cheap. Also the fact that the 3071r and 3076 were going to cost me around 2500 to get it on my car (oil lines, dump?? etc) which i was prepared to spend.

But now with the extra grand i can get other parts to help make the car reliable and last... kinda.!

[Cubes]

bazr33,

I wouldn't be too concerned. If you find its just too laggy for day to day driving slowly build up a rb30 short block as the gt35r on the rb30 short block lags less than the GT3071/GT3076 does on an rb25.

Loading up in fourth with my foot on the brake a mates rb30det gt35r .82 (plenum, stock exh. manifold, std n/a cams = more overlap = improved spool) makes 1bar by 3000rpm. General driving its all in around 3500rpm.

BUT for my needs I would like it a little more response so on my rb30det I've gone the GT3076r.

Don't be dissapointed if it doesn't really get up and go with the rb25 until 3rd gear. Its just the nature of large turbo's on smallish motors.

[Lithium]

I wouldn't be too concerned. If you find its just too laggy for day to day driving slowly build up a rb30 short block as the gt35r on the rb30 short block lags less than the GT3071/GT3076 does on an rb25.

WTF? I suppose you guys are flooded with the crappy TO4S GT3076Rs, my RB25 starts building boost quicker on my GT3076R than my mates GT3582R does on his RB30DET.... his actually starts accelerating harder earlier but thats more to do with it being a 3litre in an R32 than the turbo match to the motor. The GT3582R does take a bit of spinning to get going on the 3l, has more of a "big turbo" feel than my GT30R which feels more like a stock turbo.

Edited April 29, 2007 by Lithium

[Cubes]

WTF? I suppose you guys are flooded with the crappy TO4S GT3076Rs, my RB25 starts building boost quicker on my GT3076R than my mates GT3582R does on his RB30DET.... his actually starts accelerating harder earlier but thats more to do with it being a 3litre in an R32 than the turbo match to the motor. The GT3582R does take a bit of spinning to get going on the 3l, has more of a "big turbo" feel than my GT30R which feels more like a stock turbo.

Definitely not.

his actually starts accelerating harder earlier but thats more to do with it being a 3litre in an R32 than the turbo match to the motor.

Lag... was a poorly choosen word on my behalf. Regardless of boost being made the gt35r .82 on the 3ltr accelerates harder/earlier than an rb25 with a gt3076r.

The RB30det's power delivery is very deceiving, they lack the doughy little acceleration then everything feeling that makes a turbo car feel fast. Instead they come on smoothish (compared to a smaller motor) over a wide rpm.

Spool may have something to do with his setup, as I mentioned earlier a large short runner plenum that he swears increased response and spool a little + std exhaust manifold, and a good free flowing exhaust. Do note he also runs the rb25 n/a cams that run a lot more overlap than turbo cams; generally overlap = improved spool. Drop a set of rb20det cams in to the rb25 head and watch it lag. It starts seeing boost as early as 1500rpm.

Comparing dyno graphs on the dyno I run on; the Gt35r .82 on the RB30DET has a bee's dick more power everywhere than an rb25det with its stock turbo when tuned making close to 200rwkw. Come 3000rpm and the rb30det's curve detaches from the rb25 curve and heads north very quickly.

[Abo Bob]

Soooo you are trying to save a grand by getting a basically unsuitable turbo which will dictate that you spend at least another 10 grand to get things to deal with it?

To the thread starter, I honestly mean no offence by this but I really think you don't know enough about what you are doing just yet or have the experience to understand what you're getting into.

Comments like this give it away:

sounds like i might have to go for the rods and pistons option.

Does anyone know how much it would cost to get these fitted????

I mean, this is a full engine rebuild. It's not getting a couple of bits bolted on. This is a many thousand dollar job.

All that said, you don't sound stupid so probably another few weeks/months of hardcore reading and you should be ready to go. Feel free to keep asking questions but you can get lost for months just on this website as there is a mountain of info here. Also scam some passenger rides in some Skylines with varying levels of power (and ask the owners how much it cost them) to give you an idea of what you really want.

cheers.

[bazr33]

your right i dont know what is involved with or have experience with engine rebuilds

Thats what i was trying to find out, as when i said how much would it cost to fit rods and the pistons? Maybe i made it sound a bit broad, should of put etc. on the end.

obviously i dont know specifically else would be needed with these upgrades to make this rebuild possible.

Maybe someone that has been their, done that could read this thread and tell me what exact parts they have used and how much it has costed them.

I have done minimal research into rebuilds, but was trying to stay away from it. But if the situation occurs when/if my engine blows up. Then i know i will be looking at 10 grand plus.

As for an unsuitable turbo, yes maybe but from what i have heard and read, it sounds good too me.

Edited April 29, 2007 by bazr33

[LTHLRB]

i got quoted 5k full bulletproof bottem end machined and all engine in and out. so its a drive in and drive out deal with the lot.

so theres ur figure

if you supply parts.

CP pistons with rings

Eagle Hbeam steel rods

Nissan or ACL bearing set

ARP head bolts

Tomei 1.2 - 1.5mm metal headgasket

All new nissan gaskets etc

Edited April 29, 2007 by LTHLRB

[bazr33]

There we go, thanks heaps LTHLRB, you have been pretty helpful

I already have the 1.5mm metal head gasket, so thats one thing out of the way

Tomei cams will be next.

So now i know what parts to save for. But hopefully it will be a while before my engine gives way.

And i do know a awesome tuner that will be able to look after it when the time comes.

[LTHLRB]

go hks cams over the tomei bud.

www.horsepowerinabox.com is a good sauce for pistons and stuff

or PM Slide on the forums hese good with parts also.

Cheers.

[Cubes]

5k is a reasonable price including labour.

My short motor with just forgy's (std rods) cost me 3.8k.

The head rebuild port polish valve deshroud clean up etc cost 1.1k

Then I dropped the motor in myself.

Essentially...

Bottom end:

Block, crank rods crack tested

87mm Forged pistons & rings

Std Rods resized (no need for aftermarket rods in my case as they hold more than I could poke a stick at + I have no need for more than 7500rpm)

King HP Bearings

Balanced Heinz balancer to race spec.

Upper tensioner drilled/tapped

Cometic 0.051" MLS headgasket

Block decked with suitable finish

+ a few other little things

Head:

Rebuild

Suitable valve jobs (3 angle etc)

Port clean up

new stem seals

new valve guides

valve deshroud

combustion chambers cc'd & polished

inlet port ported cleaned up and roughened

exhaust ported cleaned up and polished

oil drains tidied up

Off the top of my head thats pretty much it.

There was also the added cost of the oil pump and water pump. All the rest gaskets/seals etc was included.

----------

Its very difficult to go past Spoolup with his forged piston and rod deals.

[LTHLRB]

yeah it was quoted by a mate of mine, but will be a little more expensive than that.

Then add in cams thats another grand and then cam gears thats 300 - 400 then ecu 1 - 1.5grand

ends up nearing the 10k range once u add clutch, turbo, injectors etc.

[Cubes]

Yes its damn scary how quick it adds up.

Also factor in a good diff, another 1k. Then sticky wide tyres :S

Never ending.

[LTHLRB]

along with that nice bulletproof engine and nice head with a good set of cams and a good diff and driveline

along comes a good turbo.. 1,500 upwards

Then suspension 2 - 4g

then rims and tyres 3g

brakes....

ohh geeze and thats just the start

If i had the opportunity to build someone an engine and driveline setup with an unlimited budget and i chose what goes in it.. It will be unfreakingbelivable

Edited April 29, 2007 by LTHLRB

[GeeTR]

I've seen an RB25Det with the GT3540 (0.82 housing)on it run over 400kw to the tyres. Boost was around 32lb i think. Aries pistons and crower rods, stock cams, and an un-ported head. It also had a metal head gasket and ARPM head studs. Crank was stock.

It barely got boost in 1st gear, in 2nd it came on like a switch at 5000 rpm with instant revs past 7500 and a hail of wheel spin and tyre smoke, same deal in 3rd and 4th.

Hi Ian,

Are you serious about that 3540 on a RB25? Iv heard a GT3540/.63 rear makes full boost on a 3L at 2500rpm and on a RB26 at 3500rpm with cams?

5000rpm on a 25 seems completely at odds to what I know!

Any clarification would be appreciated (PM if want)

[joe blo]

i nkow some1 with 450rwhp on 25 psi by 4500 rpm. on a rb25

[Cubes]

I'd think ~4000rpm is more realistic for a gt3540 .63 on an rb25 or 26.

[GeeTR]

I'd think ~4000rpm is more realistic for a gt3540 .63 on an rb25 or 26.

Hrrrmm, i better do some more research, as i thought the .8 housing was going to get me fullboost by 3000-3500rpm !!! let alone the .63!!

Thanks

[joe blo]

i think it was .82 housing for the 450hp at 25psi 4500 rpm.definately wasnt the .63

[Cubes]

The step down to .63 will reduce spool by approx 500rpm but most importantly improve part throttle and low load (first and second gear) spool and acceleration.