R33 Rb30 Conversion

[Gts-t]

discopotato03:

Which turbo do you suggest for a rb26/30 to make 500bhp with minimal lag. Cars purpose is curciut so i need something that will be perfect. However i do not have the cash to go for a new hks item, i will only be looking at something new from gcg i imagine.

Engine will use some cams, but will be internally standard otherwise. I would like to go a custom piston to bump the cr upto 9:1 but since i dont shit cash the engine will be using rb30na pistions for roughly 8.3:1 cr?

Car is a r32 gtst so fairly lightweight, thought id add that after reading your posting on cruiseliners stagea

Cheers mate !

[Cubes]

I've looked around quite a bit, looked at a tonne of compressor maps and with a little direction from Discopotato I really like the idea of the GT40 82mm 50trim comp wheel on a the GT35R .82.

I believe the GT40 82mm 50trim comp wheel is what HKS use in their HKS3040.

http://www.turbobygarrett.com/turbobygarre...82_452232_5.htm

Slightly better response and spool from the 50trim wheel over the 56trim 82mm comp wheel.

There's so many little hybrids you can throw together.

Throwing a big compressor on a restrictive hot side doesn't work all that well with the rb30's, they tend to flatten out up top and peak power rpm falls short due to high back pressure resulting in lower VE.

Similiar to what happens with a GT2510 on an RB20, Chris's RB20DET running the GT2510 makes its peak power around 5500rpm when he ups the boost, it then noses over, reduce the boost and it makes its lesser peak power higher up in the rpm.

One could make it more responsive again by dropping on a GT30R 76mm 56trim comp wheel but the only thing that disturbs me with that combo is the compressor speed vs how much air it pushes.. I don't completely understand the correlation and how it affects compressor performance if it were to be attached to the slower spinning but more torque gt35r turbine wheel.

[discopotato03]

Hi Cubes , I was hoping to get some kind of plate without metalic facings because of the "flywheel effect" and Nissan afliction with wide spaced 1-2 gearing . What was the go with that other thing you mentioned ?

Also having thoughts of VLT sized flywheel in ally and organic linings if it could work .

26GTS thats hard to say because there are so many variables though gearing and useful power range are very significant , Gary's the one to ask .

Back to Cubes , yes I'm concerned about wheel speeds as well so while the GT37 compressor (from GT3076R) could be used its hard to say whether a 3L engine could breathe through that cover at no/low boost and high RPM . The GT35 turbine and 82mm 50T GT40 compressor are probably a better speed match but the bit thats hard to know is if the 4082's compressor is the same profile and tip height as HKS's GT3040 .

I don't know if its significant but I have seen mention of a "HKS GT3540R KAI" that was being used (2) for record holding GTR's but I suspect all they are is the T51R KAI comp on the GT3540R hot side - not sure , anyone ?

I may have mentioned before that Garrett has been sneakily reducing their turbine trims on larger frame turbos ie GT4088R (78T) and T51R KAI/SPL (76T) and maybe this is on the cards for GT35 and GT30 turbines - who knows . The highest performance commonly available GT28BB turbine is 76 trim as is the TO4Z's P trim turbine . We could definitely use a lower trim GT35 turbine to speed things up a little while still having the 68mm OD to develop the shaft torque . Most GT turbines from GT30 series up are 84 trim and this is fine for low exhaust restriction but will affect the response of the turbine . I'm only speculating but Garrett is probably looking at minimum size and weight (read cost) of their turbos , and its probably more cost effective to have big trim medium sized turbines and housing families rather than smaller trim bigger diametre turbines with their bulkier/heavier/costlier housings . The choke flow may be the same but the energy recovered by the turbine will not be the same across their speed ranges .

I think there is a market for these "wildcat hybrids" such as smaller trim GT35 turbines with 76mm compressors and or small trim GT30 turbines with 71mm compressors . Cubes if you have a closer look at that plain bearing Garrett GT4082 you'll notice that its 77mm GT40 turbine is 73 trim and I don't think its a mistake that they teamed a small turbine trim with a small compressor trim . You would also notice that the difference between the turbine and compressor diametre is small ie 77mm and 82mm . If you compare the turbine map of the GT4082 with the GT3540R (1.06AR) you'll see that the maximum flow is not too different . What does hold back the GT4082's airflow a little is the .58AR comp cover which is physically a little smaller than a TO4S .70 AR (GT3540R) . I did some searches a while back on that GT4082 and some quite liked it even with its plain bearings and the weird extended turbine outlet pipe . I reckon had this been available in BB CHRA with a little larger turbine trim ie 76 and a choise of 50/52/54 comp trims it would be a good thing - with appropriate housings . The GT4088R is basically that in 78 turbine trim but the comp side climbs to 88mm so its getting big/heavy/costly/laggy again .

There really is not going to be a cheap way out of this . With what's available a GT3540R 50T gets into the ball park but the only way to tune the thing is with turbine housing AR and even this can't mimic the propper turbine trim . So I guess an RB30DET biased towards making as much low mid range as possible ie cams CR best pump fuel etc had something like this it may end up with a torque spread thats good for the street .

Cheers A .

[Craved]

hmm im thinking i should build a slapper ..

std bottom end and deck the block to up the compression ratio using the std rb30e pistons.

im running the HKS GT3040 you guys have been talking about .. i have both a 0.86 and 1.12 rear housing here so it will be interesting to see how it goes.

on the RB25 with pon cams im getting full boost at 5000rpm on the 1.12 rear housing. would love to see how the RB30det would change the response on this turbo.

[CruiseLiner]

hey cubes that clutch sounds alright for my needs, so the big question is, how much was it and how much is the bit lighter version?

anyone got any ideas on what sort of rpm a rb30/26 with stock rb30e pistons and my hks to4z 0.81 housing will make full boost?

thanks for the turbo tech info discopotato the hks version sounds good but i am on a limited budget and want value for money

heres the rough costs i have added up.. (this is for a maximum of 400rwhp)

26 head and plenum - $1000 (from a mate)

30 bottom end complete and untouched - $250

gtr injectors - $280

nismo regulator- $140

timing belt - $100

head and manifold gasket kit - $350

exhuast manifold - $300

sump adaptor - $500

single plate clutch - $500-$700 (rough guess)

tensioner - ???

gt3040r turbo - $1300 or so second hand

tomei head oil restrictors - $20

wastegate - $600

and i already have all the cooler piping, a greddy type r bov, gtr cooler, power fc djetro ecu, gtr enlarged 9L sump with baffles, full 3.5" exhuast.

i worked out for a cheap setup im still lookin at $4000 + the turbo and thats with all the bits i already have lying around.

im sure ive forgotten half the stuff but thats the basics, so i'd say $5500 is a good estimate

Edited June 30, 2006 by CruiseLiner

[Bl4cK32]

got my rb30 bottom end for $100

gates timing belt is $30 odd

tensioner x2 is $80 ea.

[FORZA-MOTORSPORT]

Anyone with an rb30 hybrid in Sa up for a cruse later tonight??? I have taken mine out last nite and clocked

280k's on 1/2 a tank no bad eh !

Pm me

Edited July 1, 2006 by FOOLBOOST

[Cubes]

I wont be....

No friggin ecu.

I think I've fried the PFC, until I get my hands on a stock ecu I won't be able to tell.

Hows it running anyway? Starting to get a little more throttle and boost in to it?

[[200]]

CruiseLiner

You should give some local wreckers a call about an RB30 bottom end.

I had a complete RB30 bottom end out of a R31 Skyline delivered to my door for $120.

[R31 POWER]

What happened to your PFC joel??

[FORZA-MOTORSPORT]

What happened to your PFC joel??

Yer what happened??? Did the resistor pack for the Gtr injectors not work and stuff you power fc??? Damn , yer i am getting her tunned on wed at tilbrooks, havent pushed her past 3500 yet

[Cubes]

Nope nothing to do with the resistor pack..

100% completely my stupid fault.. There's a little thread in the SA section regarding an elect. repairer. Its in force electronics now getting looked at, nothing is burnt it just doesn't work.

Are you tuning on the std injectors?

Who's tuning it at Tilbrooks? Tim still there by any chance?

[FORZA-MOTORSPORT]

Nope nothing to do with the resistor pack..

100% completely my stupid fault.. There's a little thread in the SA section regarding an elect. repairer. Its in force electronics now getting looked at, nothing is burnt it just doesn't work.

Are you tuning on the std injectors?

Who's tuning it at Tilbrooks? Tim still there by any chance?

Ow ok goodluck with it bro! Mark will be doing the tunning i think, im running stock 270 injectors think they have been hi-flowed or something due to the fuel consumption! My fuel pump is aftermarket remember you heard it who knows whats been done to these injectors...

im running stock cooler, afm too hopefully this wont cause any probs!

Edited July 3, 2006 by FOOLBOOST

[Cubes]

That GT35r is not going to work well with the std injectors.

I would grab an adj. fpr to help them handle 13psi or what ever the lower level is.

[FORZA-MOTORSPORT]

That GT35r is not going to work well with the std injectors.

I would grab an adj. fpr to help them handle 13psi or what ever the lower level is.

Ok ill see if i can get my hands on an adjustable fuel reg, dont they just increase the injector duty cycle if the injectors arent big enuff? wastegate is set to 13psi...

Edited July 3, 2006 by FOOLBOOST

[Cubes]

Raise fuel pressure = more fuel flow = lower duty cycle for a given power level.

[NosDan]

Raise fuel pressure = more fuel flow = lower duty cycle for a given power level.

= bad spray patterns = uneven burn = poor econ, power, and dangerous.

i hate FPRs. been tuning with them and they never seem to work nicely, but more to the point there not much cheaper than a set of 2nd hand larger injectors and there only a bandaid solution at best.

save ya money and get some GTR injectors or something and use the stock 1:1 FRP u wont be sorry

[Cubes]

bah bull shit...

Keep it within the considered save 15% and its fine.

The GT35r @ 13psi the std injectors 'should' be ok providing they have been cleaned, running a tad more fuel pressure and not pushing much past 210-220rwkw.

It will be close but at least you 'may' get away with it, on std fuel pressure there's no chance.

Foolboost, please do give tilbrooks a ring and tell them your situation, ensure they know about the stock injectors and if a gt35r pushing 13psi will require larger items or a little fuel pressure will get you by for now. (as they are as afr's are not overly rich, its probably chewing fuel as its a fresh motor and injectors may be a little dirty).

I run a bosch pump and found the std injectors were maxing out a tad early as the std wiring running to the pump was letting it down, at load the pump was only seeing 11.2v, rewired it now see's 13.8v or what ever the alt puts out to the dot.

The problem is people try to squeeze 450bhp out of 370cc injectors... This is where the problem lies. Try to squeeze a tad more in order to drop the duty cycle to a safe level and its fine.

GTR injectors hit 80% at around 230rwkw on std fuel pressure. With fuel pressure you can push 270rwkw odd but I wouldn't go much more.

So... ditch the gtr injector idea and jump straight in to 550-600cc items.

[Sydneykid]

= bad spray patterns = uneven burn = poor econ, power, and dangerous.

i hate FPRs. been tuning with them and they never seem to work nicely, but more to the point there not much cheaper than a set of 2nd hand larger injectors and there only a bandaid solution at best.

save ya money and get some GTR injectors or something and use the stock 1:1 FRP u wont be sorry

If he already has GTR injectors he is looking for around 10% increase in flow from the AFPR to make his power target. Having tested GTR injectors up to 60 psi (standard is 36-38 psi) I can say the spray pattern actually improves. Better atmosation/misting. Thers is probably a limit to how high you can go before it all turns to crap, but 10% more flow sure isn't in the ball park.

A Nismo bolt on AFPR (as used by Mines and me) costs $150 from Nengun, so it's nowhere close to the cost of an injector upgrade. And takes about 10 minuted to fit, so no labour or extra parts required.

cheers

PS, it's all in the numbers 440 cc's = 440 bhp = 331 kw - 70 kw losses = 261 rwkw at around 85% duty cycle.

Edited July 3, 2006 by Sydneykid

[Cubes]

Gary any experience with the GT35r .82 at 13psi?

Foolboost is running the std injectors. I think it will be damn close and 'possibly' just a little out of reach of the std injectors with fuel pressure.