Hi-Flow Turbo (RB25DET)

[paulr33]

i got 172 with powerfc, exhaust, cooler, boost 12psi so i doubt youll get 200rwkw

is your ecu stock? cos the stock ecu has boost cut around 12psi which will just retard everything and drop your power figure, could be remapped?

[ECR033]

I pulled 163rwkw with standard intercooler and standard exhaust (only muffler) boosted at 12psi. Since then I have upgraded to HKS cooler and 3" exhaust all the way, haven't dyno'd it since then so I'm hoping I'll have around 175rwkw at a minimum.

My next big spend will go towards Power FC and large fuel pump and Z32, then I'll think about injector and cams.

Does anyone think my hopes are too high if I aim for 200rwkw with the above mods complete? Or should I take a different approach to my next few mods?

I already have an Exedy Heavy Duty Clutch (fair few K's done on it now) It seems to be working fine.

To give you a rough idea, I've got PFC, FMIC, EBC, 3" turbo back exhaust with hi-flow cat and K&N panel filter on my R33 and I achieved 194 rwkw on 12psi.

With the mods you've listed above, I have no reason to doubt that ~200rwkw is achievable.

EDIT: Paul's post above highlights the difference in dyno readings from different workshops and why they should be used as only an indication of power. Given that we've got similar mods on similar cars, a 20rwkw difference is a little irregular when I suspect that our cars are probably pretty much in line with performance. Depending on dyno used, i expect that anything between 180-200rwkw should be on the mark for the mods you've listed.

For the record, my dyno reading was on a dyno dynamics dynometer in shoot out mode.

[Bass Junky]

I've got 200 flat with stock turbo.

Power FC

Exhaust

Cooler

Pump.

[paulr33]

Hi Mason,

Was that in shootout mode? Do you have a scan of the dyno printout? Just trying to find out why mine is 20kw less than yours with same mods

[Robo's]

I pulled 163rwkw with standard intercooler and standard exhaust (only muffler) boosted at 12psi. Since then I have upgraded to HKS cooler and 3" exhaust all the way, haven't dyno'd it since then so I'm hoping I'll have around 175rwkw at a minimum.

My next big spend will go towards Power FC and large fuel pump and Z32, then I'll think about injector and cams.

Does anyone think my hopes are too high if I aim for 200rwkw with the above mods complete? Or should I take a different approach to my next few mods?

I already have an Exedy Heavy Duty Clutch (fair few K's done on it now) It seems to be working fine.

I wouldnt bother with the fuel pump and Z32, spend the money on the power fc and you will be more than happy.

[paulr33]

the stock rb25 fuel pump and afm are pretty much at max once you fit the powerfc

[ECR033]

Hi Mason,  

 

Was that in shootout mode? Do you have a scan of the dyno printout? Just trying to find out why mine is 20kw less than yours with same mods

Hi Paul,

Yeah, it was in shootout mode. I've got the dyno sheet at home, so I'll try to scan it for you some time today or tomorrow.

I still think it's got more to do with the dyno's than anything else - although 20kw is a fair difference like you say.

Cheers,

Brenden

[paulr33]

yeah it would explain why its up a little. i wonder what it makes not in shootout mode

[ECR033]

Actually, I just noticed in your signature that you ran 11psi, whilst I was running 12psi. That's more likely a reasonable explanation (with a small degree of dyno variation) for the difference in power figures.

As for the non-shootout mode, I'm not sure. The 3 times I've had my car on a dyno, it's always been in shootout_6 mode.

[Munna]

My car made 195rwkw with of 10.5 psi of boost with the mods listed bellow on a dyno dynamatics dyno. They said fuel pump and injectors and turbo where within safe limit's but if I where to add more boost ect. I would be at the limits. He also said the R33 gts25t are probably the value for money import to modify to this level. To go the next step many parts need to be upgraded making it expensive.

To go the next step I beleive I would need

ECU, injectors, fuel pump, airflow meter and turbo

Cams would be optional but they will make a big difference.

[Cubes]

Munna, That is a higher than average figure for those mods on the usual Sydney, Adelaide, Melbourne, QLD Dyno's.

195rwkw is usually (many many r33's) done with 11psi, powerfc, exhaust, fmic.

Your mods generally get around 180rwkw. But that being said 15rwkw is well within the dyno variation.

[Munna]

Munna, That is a higher than average figure for those mods on the usual Sydney, Adelaide, Melbourne, QLD Dyno's.

 

195rwkw is usually (many many r33's) done with 11psi, powerfc, exhaust, fmic.

 

Your mods generally get around 180rwkw. But that being said 15rwkw is well within the dyno variation.

I have all of that exept Ive got a safc instead of a power FC (not of good I know) and .5 psi less boost but yeah the tuner said say it was a little higher than other cars they have tuned with similar mods.

[benm]

Don't forget that these cars are all 10yrs old now so engine condition is going to be playing a part in power output figures. It's not like they are in pristine condition after just being rolled off the showroom floor.

[predator]

correct... it's like roll the dice and see which power levels you come up with.

10% is normal, and what makes the difference between "woaa, those are good figures" and "that's about average". So the highest figure is about 190rkw +/- 10% .. and that has been proven time and time again.

[Munna]

Fair enough other things come into account too. Sometimes its not the dyno thats inaccurate if the tuner doesn't spend the time and take the care to put all the sensors in the correct positions ect results can be incorrect.

At the end of the day if you take your car to the same dyno each time and know that the tuner is not taking shortcuts when dynoing your car everytime. You should get a good reflection how much power your mods have given you.

[Cubes]

Then again..

There was Buggalugs R33 that was running the stock ecu, fmic, exhaust 11 or 12psi I forget and clocked 200rwkw on Tilbrooks Dyno.

That was a bit of a freak.

[stealth]

Hi all,

I recently bought a buggered RB25 turbo and thinking of Hi-Flowing it.

I've heard mixed feelings about this from one or two people, however I'd

like an opinion from people who have done this before and have some results

to prove.

My current mods are FMIC, pod filter, Bleed Valve, BOV, 3" turbo-back exhaust.

From my own knowledge after bolting on a hi-flow I think it will be necessary to get an Apexi Power FC (or at a minimum an SAFC), probably a Z32 air flow meter and bigger fuel pump and possibly bigger injectors.  

Does that sound about right?

I aim for around 250rwkw but with a reliable set up that won't go KABOOM on me.

From peoples experience, is it possible to easily obtain 250rwkw with a hi-flow RB25 turbo?

And if it can reach 250rwkw, what other mods would I need to build up to around 300rwkw?

I'm thinking about getting a HKS actuator over the standard, would this benefit in gaining the power I'm aiming for?

Thanks for your help..

I have just gone through this very excercise myself:

Car does 220kwatw at the moment with a 400hp rated turbo,

which is max. safe capacity. Have already got fuel regulator, pump, hiflow injectors, intercooler and PFC etc. std manafold. wanted a simple bolt on turbo to get around 400hp so turbo had to be internally gated and rated at min. of 550hp. I use the car predominately for circuit (with the occassional qtr mile run)so needed quick boost with good mid range torque - start boost at 2000 and maxed by 4000 but pwr still climbing to 7000

Through several performance mechanics (guys who actually run and tune track cars) it came down to 2 choices

1. GT35/40R internally gated rated 700hp

The internally gated GT only comes in exhaust AR1.06 which could lag but would have great legs right up to the rev limit. Has ceramic ball bearings so if backfire could risk breaking the bearing. Otherwise a perfectly matched turbo for RB25DET

2. Std nissan turbo hiflowed rated 500hp

Quite a few shops are high flowing and struggling getting 350hp, so you need to ensure who ever does the high flow is the real deal and will g'tee 550hp. Which means the inlet and out let are widened and much tougher wheels, shaft and th a bush bearings.

Although the price for both was very similar and the temptaion was to go the new I went for the hiflow because:

- good track record on some quick GTRs

- smaller exhaust AR which means ON BOOST quicker

- 12mth warranty

- garaunteed bolt on componentry

- matched compressor flow capacity with exhaust so the turbo works at an optimum speed and the lowest temp while maintaining boost

This was my experience up to choosing the turbo. Its actually being installed this weekend and gets tuned in a week so I'll let you know how it goes.

Hope this helps. What I found was the more you ask the more confusing it gets - so get advice from someone who has got the RESULTS. Good luck

[drewecrome]

You will pay about $1950 for the hi-flow kit, which is the hi-flowing of the turbo, comes with all the gaskets you need. Except the dump pipe gasket as you need to keep that one. GCG do a great job and when you get your turbo back it looks brand new and it sounds great too.

[benm]

I still think $1,950 is quite a high price for a hi-flow turbo even though it is a straight bolt-on and is the major thing making me look at a HKS/Garret kit.

[jazza08]

i very much agree wit u dude...