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Hey guys, i'm from Quebec (Canada) name's Nick.

I just want to share this with ya since i know that there's a lot of question about how much stock internal can take on a rb25det.

My car just got out of the dyno with stock internal and pulled off 454 Whp (i guess near 540 hp at the flywheel). This power is done at 19,5 psi. Tuner said that we could have near 500 Whp with taking out the silencer at 22 psi but it is way too noisy.

Base line of the set up are the following:

850 cc sard

denso fuel pump

300zx maf

300zx ecu

t3-t04e 0,63 a/r

yellow jacket coilspack

profec b boost cont.

FMIC

44 mm wastegate

BOV hks replica

Custom exhaust

Blitz catback

apexi power intake

And an amazing tuner!

4865_227265570400_694150400_7239288_4454306_n.jpg

This is more like 600hp at the flywheel. Please tell me this isn't an RB25DET with stock internals? If so, I wouldn't be expecting much more life out of them!

This is more like 600hp at the flywheel. Please tell me this isn't an RB25DET with stock internals? If so, I wouldn't be expecting much more life out of them!

really? 600? that's amazing lol

I'm running it on the low mode at 13 psi (wich give me 380 Whp). I only run on High mode on the highway when there's a racebike near lol.

I guess i can finish the summer with this motor. Since the internal are stock. I only have to swap a new motor in and keep the same set-up. This way i can do another summer or 2. :)

I'd be a tad dubious of 500rwhp (370rwkw) from a turbo that has a .63 rear housing to be honest because no amount of porting it going to make it flow that much.

With 370rwkw and tyre's you should run a low 10 sec pass resonably easily :)

Even 300rwkw (400rwhp) is about the limit over here in terms of what a ported .63 housing will flow as you can only go so far...

Every dyno is different of course so at least you now have a reference point.

As for exhaust noise - it doesn't have to be loud if you build one right. Im 90-92dB with a 400rwkw worth of flow (3.5") :D

You can never have too much exhaust flow, dual mufflers, and away you go!

I'd be a tad dubious of 500rwhp (370rwkw) from a turbo that has a .63 rear housing to be honest because no amount of porting it going to make it flow that much.

With 370rwkw and tyre's you should run a low 10 sec pass resonably easily :)

Even 300rwkw (400rwhp) is about the limit over here in terms of what a ported .63 housing will flow as you can only go so far...

Every dyno is different of course so at least you now have a reference point.

As for exhaust noise - it doesn't have to be loud if you build one right. Im 90-92dB with a 400rwkw worth of flow (3.5") :D

You can never have too much exhaust flow, dual mufflers, and away you go!

The tunning was done on a dynapack dyno. I dont' know if you know what i mean.

Anyway i know all the dyno are different but it's a difference of 60 Whp. My turbo is custom built. Maybe the guywho did it ported the housing a little bit more.

How much do you think i can go on the quarter mile on decent tire?

I think ill go mickey thompson drag radial.

The tunning was done on a dynapack dyno. I dont' know if you know what i mean.

Anyway i know all the dyno are different but it's a difference of 60 Whp. My turbo is custom built. Maybe the guywho did it ported the housing a little bit more.

How much do you think i can go on the quarter mile on decent tire?

I think ill go mickey thompson drag radial.

Ah - A hub dyno yes?

That explains it, all good, spot on then. :blink:

Its knock off ~60-80rwhp and then its back right to where the 'typical' limit of a .63 is ;)

You can only port 'so much' if you know what i mean, otherwise the turbine housing gets too thin

So with that known, 300rwkw, mid 11's at least champ. Practice will make perfect and a good launch is critical.

Ah - A hub dyno yes?

That explains it, all good, spot on then. :blink:

Its knock off ~60-80rwhp and then its back right to where the 'typical' limit of a .63 is ;)

You can only port 'so much' if you know what i mean, otherwise the turbine housing gets too thin

So with that known, 300rwkw, mid 11's at least champ. Practice will make perfect and a good launch is critical.

Alright thx :)

Can i still claim that i have 460 rwhp? lol

As for the ''brave'' thing, i won't take this as a compliment lol... we'll see i guess...

That explains it, all good, spot on then. :blink:

Its knock off ~60-80rwhp and then its back right to where the 'typical' limit of a .63 is ;)

With all due respect while its known there is a bit of a difference between the two type of dynos, there is no way my car running a .82 GT30R on 1bar would be making <220rwkw on a Dyno Dynamics dyno?

You can only port 'so much' if you know what i mean, otherwise the turbine housing gets too thin

So with that known, 300rwkw, mid 11's at least champ. Practice will make perfect and a good launch is critical.

Can't really say too much without him telling what trim turbine wheel he's running and what compressor etc, there are many many different variations of "T3/T4" turbos and most of the ones people seem to use on RBs in NZ/Oz are the far less aggressive ones but looking at the lag in that plot its probably something a bit more substantial. 370rwkw on a hub dyno, because Dyno Dynamics seem so inconsistant amongst tuners I won't guess how it relates to one but if its set up the way most tuners I know run them I'd expect this car to be running in the area of 130mph trap speeds on the 1/4.

As it stands, this car actually made just under 340rwkw - still plenty sufficient for 11s at >120mph, would be interesting to see how it goes.

Edited by Lithium
The tunning was done on a dynapack dyno.
With all due respect while its known there is a bit of a difference between the two type of dynos, there is no way my car running a .82 GT30R on 1bar would be making <220rwkw on a Dyno Dynamics dyno?

Dyno Dynamics

2WD450DS.jpg

is not the same as

Dynapack

deman%20porsche.jpg

As one can see, one gives a hub reading and one gives a wheel reading. While this could be compensated for, generally the hub dyno's read out higher numbers as there is no wheel mass rotating or slip between tyre and roller (although this should not be the case if the car is tied down correctly.

Ah - A hub dyno yes?

That explains it, all good, spot on then. :blink:

Its knock off ~60-80rwhp and then its back right to where the 'typical' limit of a .63 is ;)

You can only port 'so much' if you know what i mean, otherwise the turbine housing gets too thin

So with that known, 300rwkw, mid 11's at least champ. Practice will make perfect and a good launch is critical.

Yes. i am thinking 350hp at rear wheels would be where this is at.

Dyno Dynamics is not the same as Dynapack

As one can see, one gives a hub reading and one gives a wheel reading. While this could be compensated for, generally the hub dyno's read out higher numbers as there is no wheel mass rotating or slip between tyre and roller (although this should not be the case if the car is tied down correctly.

I am very well aware of the difference between the two, and I always run my car on Dynapack dynos - hence my comment. My car has made 270kw @ wheels on between 1-1.1bar on a hub dyno, if you knocked 60whp off that I'd be under 220rwkw on a Dyno Dynamics.... so you guys are effectively saying that a healthy RB25 running a .82a/r "real" GT3076R tuned to make 270rwkw on a Hub dyno will make under 220rwkw (using the take 60whp off thing) on a Dyno Dynamics dyno, despite the fact that the combination normally makes way more power than that on a DD?

Edited by Lithium
With all due respect while its known there is a bit of a difference between the two type of dynos, there is no way my car running a .82 GT30R on 1bar would be making <220rwkw on a Dyno Dynamics dyno?

Can't really say too much without him telling what trim turbine wheel he's running and what compressor etc, there are many many different variations of "T3/T4" turbos and most of the ones people seem to use on RBs in NZ/Oz are the far less aggressive ones but looking at the lag in that plot its probably something a bit more substantial. 370rwkw on a hub dyno, because Dyno Dynamics seem so inconsistant amongst tuners I won't guess how it relates to one but if its set up the way most tuners I know run them I'd expect this car to be running in the area of 130mph trap speeds on the 1/4.

As it stands, this car actually made just under 340rwkw - still plenty sufficient for 11s at >120mph, would be interesting to see how it goes.

You dont know how someone else's in another country is setup. Neither do i!

Apply your knowledge just for a second to THIS particular thread/result... as follows... :D

1. Its a .63 rear housing - Regardless of how much air you are putting in the front end, you are only going to fit 'so much' out the rear end.

2. You can see it does probably have a large-ish rear wheel (possible backcut and so on), being it comes onto song around the 4500rpm marker, which is where my T04E with a .82 rear housing started to sing. So its flowing out the rear, but not 370rwkw worth either way.

3. I've seen some results posted here about hub dyno's and people then are suddenly 'missing' 6-10mph... thats not just a little, that's a lot of power that has disappeared.

As always, happy to be proven wrong. When he takes it to the track and runs some MPH we'll see where it roughly lies, but like i said, I'm not so confident.

Not saying its a bad result or anything, its a reasonably solid setup no question there.

Can i still claim that i have 460 rwhp? lol

Nope, its not actually "at" the rear wheels :P

You dont know how someone else's in another country is setup. Neither do i!

Exactly :D

Its a .63 rear housing - Regardless of how much air you are putting in the front end, you are only going to fit 'so much' out the rear end.

Different wheels/housings etc can relate differently. A .64a/r GT25R isn't likely to touch 200kw @ wheels, a .63a/r GT35R will crack 350kw.

2. You can see it does probably have a large-ish rear wheel (possible backcut and so on), being it comes onto song around the 4500rpm marker, which is where my T04E with a .82 rear housing started to sing. So its flowing out the rear, but not 370rwkw worth either way.

He actually hit 340kw, his 370kw @ wheels was speculative and I pretty much wrote that off... if he bumped the boost up he might discover hints that it wasn't going to go much higher anyway

3. I've seen some results posted here about hub dyno's and people then are suddenly 'missing' 6-10mph... thats not just a little, that's a lot of power that has disappeared.

Not sure which cars you are talking about. I know mine has done low trap speeds for the power it has, but that has been more to do with me never being able to get at the power I was making on the dyno due to fun things like ignition misfires and boost leaks :P

As always, happy to be proven wrong. When he takes it to the track and runs some MPH we'll see where it roughly lies, but like i said, I'm not so confident. Not saying its a bad result or anything, its a reasonably solid setup no question there.

Ditto the other side, I am actually leaning more towards somewhere in the middle. There are plenty of people out there who have made ridiculous power (and the times to suit) on .63a/r T3/T4s for years - in our part of the world it seems they haven't been looked into or as understood as elsewhere but it doesn't mean it can't be done. I'm just saying don't bag a setup you aren't familiar with too quickly. Pretty sure the fastest pump gas EVO in the world (traps near 150mph) runs a .82a/r T3/T4 :P

I made an estimate on what trap speed I'd hope from a Skyline making xxx.kw on a Dynapack dyno as I am more than familiar with them, much as you guys are familiar with Dyno Dynamics. I know that an R33 making ~370kw @ hubs set up "normal" should run 127-130mph or a few less with 340kw, to put it more into perspective.

Edited by Lithium

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