billet wheels on rs2 turbos...

[mouse]

Had my billet Iroz turbo mapped in Feb 2014 but only on stock RS2 injectors. Have run it for several months and around the track this weekend!!! Love it.

Currently running 347 crank HP

My RS2 injectors are however maxed out so have just purchased some larger ones and Water meth injection.

When this is all mapped and dyno'd I will report back.

Is this their K26 or RS2 turbo?

[Tonks4x4]

Is this their K26 or RS2 turbo?

It's the K24-7200 RS2 turbo

[Quattronaut]

One question: I see 2 results. One with E85 does 380hp, and the other does 350 with normal fuel. Both use billet wheels from Iroz; is it the same wheel? And, the important thing- why? These results are near to what you can get with stock RS2 turbo afaik, or am I wrong?

[urS6Tom]

Had my billet Iroz turbo mapped in Feb 2014 but only on stock RS2 injectors. Have run it for several months and around the track this weekend!!! Love it.

Currently running 347 crank HP

My RS2 injectors are however maxed out so have just purchased some larger ones and Water meth injection.

When this is all mapped and dyno'd I will report back.

Looking forward to hearing about this as I purchased a billet RS2 from VRS recently. Who is doing the mapping for you?

[dobbin]

rs2 wheel

I dropped off car on Monday morning to mrc they said they would need a week to set up
and test also doing 4 wheel alignment.
I sent link to cr turbos about iroz billet wheel . they said 10 blade gtx design wheel
was causing problems stalling that's why gtx turbo has porting. they have been changing gtx turbo wheels in place with 7 double blade billet and found better results.
my criteria to cr turbos was better spool up and higher mid to top end pull.
I quoted I wanted 400 ish bhp

[dobbin]

rs2 mrc tuned

just had this sent from mrc tuning.

[A80Avant]

Got what you wanted then!

What's disappointing is that at least on the graph the billet wheel doesn't seem to do anything better in spool/lag than the original. However you do get to 400 hp which the original wheel doesn't get you

[dobbin]

rs2 mrc

yes that seems to be but I have not driven it yet to find out. doug has and says very impressive upgrade and all round performance. but only running 1.7 bar boost and down to 1.4

[URQguy]

My 2 cents on the topic

The choke factor on any of the KKK hybrids is the turbine housing. A #6 hotside will only support ~360whp worth of airflow no matter how big of a compressor is placed on it. A larger turbine like the k26 will cheat the AR slightly, but in the end, it is a bandaid in exchange for more lag. Adding bigger compressors to #6 setups will only make lag happen and have poor transient response, even in k26/k27 hybrids. Until somebody casts #8 hotsides for the rs2 turbine, the limit on power is ~370whp on e85 or race fuel. Any more then that is just a happy dyno or sand bagged dyno techniques to give a number. We have a dyno and have run massive amounts of tests on various hybrids. The best fit is a 4852 setup the RS2 turbine to end up with slightly better spool than RS2 but still be able to hit the Turbine Housing limit at 370whp.

The stock RS2 is a 47.5, our 1st gens are 48.5mm and are second gens getting ready to drop are back to 48mm as we can get the flow rates in a 48mm that will max the turbine housing.

We have a really neat k24 billet coming out that should actually make the rs2 billets obsolete FYI. It is in testing and is again playing on the theory that a #6 hotside(or .42AR in garrett terms) can only do so much work, so why overload teh assembiles with bigger wheels to get marginal gains in the name of lag?

[URQguy]

Oh and we have had zero problems with a 10 blade on our hybrids. Garrett ports their housings because they are running compressor heavy assemblies that push more air than the turbines can handle and put them into surge. With our rs2 hybrids we are runninga 48.5/52mm ratio compressor to turbine, which means it does not surge, and the antisurge is not needed. We have been testing 6 blades, recently and they have been approved on the premise that again the higher pressure ratio efficiency gain of a full blade 10 blade is not realized if it is being run with a #6 hotside. It is better to get a wider midrange to take advantage of the #6 restriction while the flow is acceptable.

Cheers

[Ross]

Peak torque at 3700rpm and 405hp sounds good to me! I'd have got one based on those results. My current hybrid also based on a k26 #6 should yield similar power but another 1-200rpm lag, albeit slightly higher boost (2.1/1.5).

[dobbin]

rs2 turbo

ross are you running k26/27 hybrid from hoffer if so what bhp and torque levels at 2.1 bar.

im running k24 7200 std exhaust side and billet wheel 5mm larger than std.
interesting to see different results on driveability and power have you got a rolling road plot? I will ask doug the question of what if I run my turbo higher boost to see the gains.

[Rusty]

Good work on a near stock engine!

[driftin jo]

One question: I see 2 results. One with E85 does 380hp, and the other does 350 with normal fuel. Both use billet wheels from Iroz; is it the same wheel? And, the important thing- why? These results are near to what you can get with stock RS2 turbo afaik, or am I wrong?

your wrong, as you are talking hp and they are talking wheel hp, bit of a difference,
a stock RS2 turbo does ~300 wheel hp

[Ross]

ross are you running k26/27 hybrid from hoffer if so what bhp and torque levels at 2.1 bar.

im running k24 7200 std exhaust side and billet wheel 5mm larger than std.
interesting to see different results on driveability and power have you got a rolling road plot? I will ask doug the question of what if I run my turbo higher boost to see the gains.

I've not had it on a dyno running right to confirm as of yet. The figures from mapping suggested about 420hp ballpark for power. Torque is pretty insane in the midrange what with that 2.1bar peak. I would expect running higher boost would not yield any more top-end but would get you a higher peak torque.

As soon as I have it running again I'll be getting it on a dyno. Just no time to finish the suspension overhaul that i started.