Better Turbo For Built Rb25Det

[Lithium]

The people who have recommended the GTX3076R - have you guys wondered at all about how the GT30 hotside will support GT3582R levels of compressor flow? Borg Warner have done a similar flowing 76mm compressor in the form of the EFR 7670 but they have gone with a bigger hotside than the GTX3076R, and I am wondering if the GTX3076R may end up being a bit more like a better spooling GT3082R.

I am awaiting results on these new turbos before I get too excited, the GTX3071R is the only one I can see being fool proof and one of those aren't going to meet this lads requirements.

[R31Nismoid]

Can you give me a little more input why you think I don't have the setup for 550rwhp? This has been a 3 year project and I'm committed to my goal. Thanks.

Because some of the craziest, dedicated circuit cars, are around the 650-700hp region.

Unless you intend to go all out, balls to the wall style modifications... I just feel it's over the top.

These guys are all running strokers on what are probably 30-40k motors and so on, so they are able to sit in that region without as much issue.

[R31Nismoid]

The people who have recommended the GTX3076R - have you guys wondered at all about how the GT30 hotside will support GT3582R levels of compressor flow? Borg Warner have done a similar flowing 76mm compressor in the form of the EFR 7670 but they have gone with a bigger hotside than the GTX3076R, and I am wondering if the GTX3076R may end up being a bit more like a better spooling GT3082R.

I am awaiting results on these new turbos before I get too excited, the GTX3071R is the only one I can see being fool proof and one of those aren't going to meet this lads requirements.

Can't say i had an issue with my 3040 (600hp) item. The GTX3076 would be what, 600-650 now?

[bradsm87]

Haha wierd coincidence. I was just thinking about that before reading this thread.

They should make a GTX3576R.

I really think Garrett make good compressors, cores, turbines and housings but do a shit job of matching them all together in some cases.

Mitsubishi and Borg Warner have their compressor wheels and turbine wheels much more similar in size.

[Lithium]

Can't say i had an issue with my 3040 (600hp) item. The GTX3076 would be what, 600-650 now?

What a/r hotside were you running, and how much power did you make with it?

[GTScotT]

lol @ live with 550rwhp on dynojet - funny guy.

I really want to note here that your current supporting setup is lacking for 550rwhp, and it is possibly what is holding you back at the moment, as has been said already.

I believe the cost to benefit ratio between hitting an actual 550rwhp and swapping turbos to max out your current setup may weigh heavily in the smaller turbo department.

I forsee selling your turbo and a retune could see costs under $2000 with all things considered... Where as supporting changes to see 550rwhp could easily be double. As stated also, the car is light and having it on power sooner (and with similar power to what you have currently) could be an awesome change for the best.

Have you seen:

http://www.skylinesaustralia.com/forums/topic/347726-kando-dynamics-turbo/

That turbo seems to be of 35R power and has been seen to produce 3076 type response (in posts by Status with 180rwkw[250rwhp] by 4000rpm from memory)... It also costs under $1000 AUD delivered.

[R31Nismoid]

What a/r hotside were you running, and how much power did you make with it?

.82

45mm gate

GTSR manifold.

270 @ 17 PULP

370 @ 24 SUNOCO 104

it'd be well into the 300 on PULP. my bad 3" exhaust caused issues.

and then i was EPAd, so took out the setup before getting a 3.5-4" done.

[Lithium]

Ah ok so really kinda hard to compare ultimately

[JonnoHR31]

if your looking for that sort of power and to make the most of the new compressors i'd go a 1.06 housing on the gt30, twin scroll if your manifold allows it. it wont get you 550rwhp (on our dynos anyway, not sure how different yours are) but it should make a solid 450rwhp with a very nice midrange

[R31Nismoid]

Ah ok so really kinda hard to compare ultimately

Yep

Its just a theory, but it did make the power on fuel - which does tend to mask exhaust issues to a point - so it can at least flow that much.

I really wish i had a chance to see it to the end, but ye, 25 out, 26 in!

[radianation]

Again -- appreciate the suggestions and advice...

I don't want to revisit all of the details of my very disappointing introduction to the tuner world and how much money it has cost me, but let's just say that I'm not looking for a quick fix or a cheap solution. I've seen one additional piece of information about getting the engine to perform at a 550rwhp level (stroker kit), but I have also seen contradictory information... Suggesting that a simple turbo fix or increasing the psi to 22-24 will achieve the power is odd since people are also saying that the car is not capable of 550rwhp.

For the sake of argument... Let's just assume money is not an issue. What will it take to get this engine performing 550rwhp reliably on pump gas while not sacrificing spool?

I've wasted a lot of time and money going on hearsay from forums in the US, but I really need some concrete facts on whether or not this engine is capable of doing what I want?

Edited December 17, 2010 by radianation

[zebra]

I would start with the fuel system, a Nice 4L surge tank with twin pumps.

Some nice tough valve springs

Bigger exhaust and dump pipe + good 4 or 5" body cat

Do you have pics of your exhaust manifold, maybe spend some coin on a Full Race one.

Can I ask what duty cycle you are seeing with the 850cc injectors?

How much timing are you running?

What Intercooler are you using?

What compression ratio? from memory the Weiso's are quite low on comp + your head gasket

[radianation]

I have a lovefab exhaust manifold. Pics are not the best:

Injectors were around 60% duty cycle during last dyno tune. Fuel delivery did not seem to be a limitation at that time, but I agree the fuel system is not very stout. Already researching a surge tank thanks to your suggestion. Any specific recommendation on pumps? Most people doing RB swaps go for the Walbro, but it does seem to be a shortcut... I don't want my fuel pump failing on the track. =)

I will grab a screenshot of my timing map from the AEM EMS tomorrow and post it here.

I do not know what kind of intercooler - it appears to be generic fmic.

I do not know the exact compression ratio. I have Wiseco 20+ pistons and a Cometic 1.1mm head gasket. Thank you btw.

[radianation]

Also, back to the possible issue of valve float, if you watch in this video, right about the time where the dip is in the power on my dyno chart you see a puff of black smoke from the exhaust. Any clue?

[PM-R33]

Who ever is telling you 550rwhp is not possible knows nothing about RB25 engines.

[zebra]

Nothing wrong with that exhaust manifold!

For the pumps i would go 2 x Bosch 044's or if you like the walbros go 2x the inline Walbro, (GSS-341?)

The puff of smoke could be a number of things, but the video doesnt give any real clue as to what is going on (to me anyhow)

[GTScotT]

I honestly cannot hear valve float in your video, however you are well beyond the known point for stock valve springs.. So I would change these and save the heartache later.

To get to your powergoal I would agree with what has been advised as is:

Run a fuel surge tank, lift off your existing walbro then 2 x pumps up the standard line.

Completely new TBE. 4" dump minimum and 3.5" catback minimum.

More boost.

A proper intercooler (not a generic china item). - my addition

If the above doesnt work for you.. you know a change of turbo SHOULD be the trick (assuming you dont just have a dud motor).

Be it myself chasing 400+rwkw (550rwhp), my turbo choices would be T04Z, GT3788 and GT4088. I think the T04Z is the safest option, it is documented to death on this forum... Give the search a wurl. I honestly know Nothing about your current turbo.

[radianation]

Good tips. So no need to upgrade the OEM fuel lines when going to 2 x pumps and surge tank?

My current wastegate is plumbed back into my exhaust at an angle where the dump pipe bends. I'm thinking about removing this and going open wastegate. Now would be the time to decide as I configure an entirely new exhaust.

I wish I could find out what intercooler I have. The shop who assisted me with this originally from 3 years ago purchased it and claimed it was a quality product, but I've never seen a name on it. =/

I'll do some more searches on here for the T04Z feedback.

Edited December 17, 2010 by radianation

[R31Nismoid]

Suggesting that a simple turbo fix or increasing the psi to 22-24 will achieve the power is odd since people are also saying that the car is not capable of 550rwhp.

nonononono... the MOTOR is capable, but the driver/car setup/cooling etc - is not.

Anyone can make power on a dyno mate.

Its getting it to last 3-5 years that is the real challenge

[radianation]

I agree - making power is no good if it's not sustainable, which is why I've taken steps to improve the weak points of the engine. However, you're still not qualifying what you're saying, and I am a little confused now as to why you're suggesting that the driver is not capable of producing 550rwhp?

Also, the power has lasted (so far) for 3 years. It's just not my goal.

Edited December 17, 2010 by radianation