Jump to content
SAU Community

500kw Rb25det

Gta51

By Gta51,
in Engines & Forced Induction

 Share

Recommended Posts

Gta51 Collaborator

Gta51

Posted
Posted (edited)

Hey guys

Currently making 415rwkw with a gtx3582 .82 rear housing on 27-28lb boost. What's the best way of getting close to or over 500kw? Would a bigger rear housing suffice ? If not what turbo is the next logical size up. Running a forged motor with all Nitto gear. Currently out of fuel system (single walbro 460lph) so couldn't push more , ill be adding two extra 044 fuel pumps into the mix

Edited by Gta51
Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/
Share on other sites
Gta51 Collaborator

Gta51

Posted
  • Author
Posted

Would the biggest size tomei poncams help boost it aswell? fairly sure I have stock cams in it atm.

Cars a street car so I want to stay away from nitro meth etc loll

Im thinking a 1.06 rear housing, cams, and abit more boost should get me close to that

Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7567193
Share on other sites
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

If you have a GTX35 and only making 400-420rwkw though @ 27-28psi you've kinda got a problem... Assuming you are on E85 as well.

Should be a bit more than that. A GT35 will do 400rwkw on E85 with that amount of boost. The GTX flows more air, it should be well past it and around 440rwkw or more.

Could be a restriction somewhere or something else entirely. I'd be working out what is wrong first before going for more power/part changing.

Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7567818
Share on other sites
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

But a 500kW turbo LS is a very much more "streetable" engine than a 500kW 2.5 L RB!!

It's funny when the "400-500rwkw" street guys get asked what MPH they run, quite often it's FAR lower than what it should be.

Proof is always in the pudding there :)

  • Like 1
Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7567915
Share on other sites
STATUS Grand Master

STATUS

Posted
Posted

So agree with nismoid.

I remember a long time ago when this wasn't the case.

Ahh the good old days when saying you had a fast car actually meant, ummm, you actually had a fast car.

Mph will always rule the roost.

So agree with nismoid.

I remember a long time ago when this wasn't the case.

Ahh the good old days when saying you had a fast car actually meant, ummm, you actually had a fast car.

Mph will always rule the roost.

most cars cant handle it... we have high 300 cars running 9-10 then 500kw cars running 10-12s lol.... MPH is no longer an accurate SOLE indicator

perfect example

  • Like 1
Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7567977
Share on other sites
Gta51 Collaborator

Gta51

Posted
  • Author
Posted (edited)

If you have a GTX35 and only making 400-420rwkw though @ 27-28psi you've kinda got a problem... Assuming you are on E85 as well.

Should be a bit more than that. A GT35 will do 400rwkw on E85 with that amount of boost. The GTX flows more air, it should be well past it and around 440rwkw or more.

Could be a restriction somewhere or something else entirely. I'd be working out what is wrong first before going for more power/part changing.

Stock cams and a single fuel pump limited me. Once I add another pump and cams I'll see that figure with a retune I'm fairly sure. I get what your saying though :)

Edited by Gta51
Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7568060
Share on other sites
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

most cars cant handle it... we have high 300 cars running 9-10 then 500kw cars running 10-12s lol.... MPH is no longer an accurate SOLE indicator

perfect example

Yeah but in GTS-t / GT-R land - There are so many results it's pretty easy to work it out where a car should be (say +/- 3/4mph). Some cars are like 10mph down (some are up lol), that ain't a result of a car that can't handle the power. Generally from what I've seen, if you have less traction you end up with slightly higher MPH - big more bragging rights at the pub isn't necessarily a bad thing lol :)

Most R33 GTS-t owners with 300-340rwkw are around the ~127mph

R33 GT-Rs with 300-340rwkw get around the ~124mph, if it's a R32 you're a little higher as you weigh less and so on.

Of course it's never gonna be 100% accurate, but you can get in the ballpark. Same as when someone posts up their GT-R is making 370rwkw on -9s never got anymore than like 120mph... Result debunked, you didn't have 370rwkw! Not a chance.

Then there was a 450rwkw 33 GT-R recently in NSW I saw that I think was like 124/125mph. Even without doing a big launch, something ain't right, it should be over 130mph easy.. Either it didn't have the power on the night or someone was singing hey diddle diddle in the dyno room

  • Like 1
Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7568089
Share on other sites
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Stock cams and a single fuel pump limited me. Once I add another pump and cams I'll see that figure with a retune I'm fairly sure. I get what your saying though :)

I had a big post for ya and my internet died lol. Poop.

Anyway I think fix the fuel pump and then see? It's pretty easy to do... IMO you should've run outta fuel before you got to 28psi. That's a LOT of pressure/flow needed outta the pump. Guys here on PULP have made ~370rwkw with a GT35 and stock RB25 head (around the 22psi marker). Then to get the 400 E85 and a bit more boost, and that's a smaller huffer and you really are running some good boost.

I mean look it might be nothing, or maybe you'll find 30rwkw easy just getting the fuel it needs? Even something simple like dropping the exhaust at the dump/cat you might just pick up 30rwkw. Sometimes even with a little restriction a set-up can still perform very well, just not perfectly type thing.

Obviously with head/cams etc you will potentially make more but something currently just doesn't sound right if you know what I mean? I'd be sorting the bits around it and checking a couple things first if you haven't already

Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7568097
Share on other sites
XGTRX Veteran

XGTRX

Posted
Posted

most cars cant handle it... we have high 300 cars running 9-10 then 500kw cars running 10-12s lol.... MPH is no longer an accurate SOLE indicator

perfect example

https://youtu.be/Po10g8VGKTI

ETs have always indicated setup, MPH have always indicated power

Nothing has changed.

Dynos lie, MPH don't.

  • Like 1
Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7568099
Share on other sites
Gta51 Collaborator

Gta51

Posted
  • Author
Posted

I had a big post for ya and my internet died lol. Poop.

Anyway I think fix the fuel pump and then see? It's pretty easy to do... IMO you should've run outta fuel before you got to 28psi. That's a LOT of pressure/flow needed outta the pump. Guys here on PULP have made ~370rwkw with a GT35 and stock RB25 head (around the 22psi marker). Then to get the 400 E85 and a bit more boost, and that's a smaller huffer and you really are running some good boost.

I mean look it might be nothing, or maybe you'll find 30rwkw easy just getting the fuel it needs? Even something simple like dropping the exhaust at the dump/cat you might just pick up 30rwkw. Sometimes even with a little restriction a set-up can still perform very well, just not perfectly type thing.

Obviously with head/cams etc you will potentially make more but something currently just doesn't sound right if you know what I mean? I'd be sorting the bits around it and checking a couple things first if you haven't already

Spot on fuel pump was the biggest limiting factor for me. So I'm going to add another Walbro or two 044 pumps. Might aswell add cams since I'm getting retuned, always wanted to do that anyway

Link to comment
https://www.sau.com.au/forums/topic/458183-500kw-rb25det/#findComment-7568108
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • MBS206
      Dose's Sometimes DIY and Pay Someone Home & Boat Improvement Thread

      By MBS206 · Posted

      Why are people so insistent on making dirty water?!
    • Dose Pipe Sutututu
      Duncan's V37.......race car?

      By Dose Pipe Sutututu · Posted

      Fark what are the changes of that snapping like that, clean. Nek minnit, custom radiator goes in, with built in oil cooler like those discontinued PWR ones from yesterdeacades ago
    • Duncan
      7 Speed Auto transmission fluid change (Skyline, Q50, Q60, Fuga, Q70, A62 Titan and probably heaps of others including Navara...)

      By Duncan · Posted

      I thought I'd do a write up on an auto transmission fluid change for a the nissan 7 speed Automatic. At some stage the genius engineers decided that the fluid in the trans was "for the life of the transmission", (which seems kind of self supporting to me) and removed the dip stick and fill tube (funnily enough there is still a casting for it). Anyway, for this job you do need 2 specialist tools in addition to regular hand tools, jack and good chassis stands. You need a way to pump fluid up to the transmission; I got one of these but there are plenty of other options: https://www.ebay.com.au/itm/364584087070 Don't trust the generic listing though, it does not come with the required adapter for the Nissan 7 Speed. You need one of these, can't do the job without it: https://navarapart.com.au/product/genuine-nissan-patrol-y62-d23-np300-navara-re7-dipstick-fill-connector1 You need a heap of compatible transmission oil. Could be Nissan, could be anything else rated for Nissan Matic S. You need at least 10 litres, I had 15 to give it a better flush... Also, you need some biiig oil catch trays, at least one of these, or bigger if possible (volume was fine, size was very marginal): https://autobarn.com.au/ab/Autobarn-Category/Tools-%26-Garage/Specialty-Tools/Oil-Service/Garage-Tough-Oil-Drain-Pan-Black-16L---GT1068/p/TO03191 Finally, a measuring jug is very useful if your pump does not have volumes marked on it, I got a 6l one: https://www.repco.com.au/oils-fluids/fluid-accessories/measuring-jugs/penrite-measuring-jug-6l-pmj006/p/A5322648 Oh, and gloves.....this stuff is horrible (not as bad as diff oil, but getting there) ....First, jack up your car.....
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      So I mentioned the apprentice, @LachyK helped take the bonnet off. We just undid the nuts on the hinges and unclipped the gas struts, then pulled the bonnet back a little as the front was catching on the front bar.  I had a good look at everything today and have removed the rams, repaired/reset the hinges and bolted it back together like it never happened. I'll do a separate write up on the repair, and I also removed the poppers from the Fuga today too to save grief down the road.....as said above it is at least $5k to repair retail. I'm also happier about my ability to prepare a race car, and less happy about Nis-nault's engineering (I can hear @GTSBoy sAfrican Americaning) because the top hose of the radiator didn't slip off.......it snapped clean off. By practice I put the hose clamp hard up against the flare on a neck to make it least likely to ever move (thanks @Neil!). I guess that puts a little more pressure on the end of the pipe as it is further away from the rad, but still, that is pretty shit. I've put it back on for now as there was a fair bit of neck still there, but obviously there is no lip on the neck any more so I don't think I'll track it again until I have a new rad. Speaking of which....more research required. It looks like Koyo makes a standard size radiator in ally which I'll grab in the meantime, but I really want something thicker so might have to go custom in the medium term (ouch) Coolant still needs a refill and I have the pressure tester on it over night, but other than a wash down of the engine bay it seems alright. And @MBS206 noted something noisy on the front of the engine and I think I agree....time for a new accessory belt and tensioners I think.
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      our good friends at nismo make a diff for it, I have one (and a spare housing to put the centre in) on the way. https://www.nismo.co.jp/products/web_catalogue/lsd/mechanical_lsd_v37.html AMS also make a helical one, but I prefer mechanical for track use in 2wd (I do run a quaife in the front, but not rear of the R32)
×
×
  • Create New...