turbochargers for 500hp

[prj]

With GTX3076R we would probably see similar spool but more top end power.

No, you won't.


A bit better spool, but exactly the same power at the same boost (stated by the person who produced the graph). So the turbine does not flow any better.

As for holset… HX35S spool on bone standard 2.2T with a fairly quick ramp rate, full boost is at about 4k here. This is just a bit quicker ramp rate than with 3rd gear on the road. Power and torque is at the wheels, so 600nm at 4000 rpm, and 645nm peak, and power is about 550hp, but WMI helps a little here



If you compare quattro-nick's result on the same type of dyno:


The turbos spool in a similar way, the HX35S comes in a bit earlier (550nm vs 600nm @ 4000 rpm). The power figures is hard to compare without knowing the correction factor on the dyno used by quattro-nick, as the superflow here only gives wheel power.

[pasbogdan]

Question was for race track. When he does hill running, he has to tell us so :-)

Was looking at gtx3076r. But also thought about holset hx35?

Also been offered used gt3582r and gt3082r

thoughts on all these turbos. Looking for around the 500bhp mark on an aan engine with rods.

Thanks
nick

It was a general question.
@bartolomeus,you have an evo now and you start wandering about throttle response? It is instant.As it is in your octavia 3 rs 2.0.

[bartolomeus]

I have a question. Maybe I'm silly. Why not ALS? That's the thing to have in motorsport?

[Quattronaut]

Question was for race track. When he does hill running, he has to tell us so :-)

[pasbogdan]

For short: at 7000rpm NMs=HP.

Good response is necessary for track use, yes- but setting the peak power too low in rpm band is not optimal IMHO, because you are normally revving the gears out due to the lower gear ratio. So power from 2500-6000 won´t make you to happy. After revving to 7200 and then change gear, you are around 5500 rounds, depending on which gear it was. In this range, torque ist going down. So you loose 2500 rpm of real torque.

I would set the peak power to around 7000rpm. With a good charger at 2,2L, boost then kicks in at around 4000 rpm, what fits better the profile of driving on race track, than an motor, that has torque from 2500 to 6000 rpm.

I´m just building up a 2,5L stroker with K26/27;
estimated:
1,5 bar/ 550NM @ 3000rpm
2,5 bar/ 750NM @ 3500 to 4500rpm
2,0 bar/ 540hp @ 6500rpm

I do not want to discuss this setup in here; but this IMO woul not be optimal for track, because peak power and max torque are too early in rpm band. With the same charger and 2,2L, both points should be 500-600 rpm higher, what fits track use much better.

This thinking is for track.But what do you do if you like your car for rally/hill climb?
400 hp aby s2 with hx35 and k26 hotside is worse to drive and i can bet time on a tight corners ss or track is worse compared to k24 7000 turbine with 1.5 bar peak and 1 bar at redline mod.
The question is what you want to do with your car?

[snp10]

Good result. Maybe with w/m system you can gain more power.

[quattro-nick]

today dyno result gt3076r A/R 0.82

http://www.s2forum.com/forum/showthread.php?t=73865

[Quattronaut]

So here we are with turbos for 500hp:

Garrett GTX3071/ GTX3076
BorgWarner EFR7064/ EFR7670
KKK K26/3371O 8.12 (12,5)/ K27.2/3371O 9.12

The first ones for just around 500hp, better spool, the second ones for more power, more lag.

Some Turbonetics, Precision and Holsets as well, but since I do not know them, someone else should name them :-)

I would prefer the second chargers, as they will give not only more power, but the power at the right place in the rpm-band.

[nicksonmsport]

this car will be light approx 1 tonne, and it will be rwd so more power at wheels compared to 4wd.

as said the torque band needs to be between 4000-7500 rpm to make most of in gear acceleration on track. I just want the turbo to spool up nice and quickly between gear changes so the power is on tap straight away.

[A80Avant]

We are talking about torque not power !!!
I want that 600Nm all the way across the Rev range. Torque translates to the cars ability to accelerate which is where the fun comes in and of course improved agility in competitive use. Power translates to maximum speed which is all fine wide open on the autobahn but not something you can use every day !

Which practically makes a this 500hp turbo setup talk pointless as the most important factor which is what is the car used for is missed out.

As you I want an everyday responsive car. Therefore I'm not interested to change gears at 70 rpm and the rest of it. I'm interested to be agile. Why would I want 500hp? Well because at 1.7 tons it's not the lightest car to move around and also I don't want it to be a diesel and drop off any power after 4000rpm

[Thuppu]

I had a 235hp/700Nm diesel Bimmer that got the max torque at 2000 rpm's. If I compare it to my UrS I must say the UrS is a lot more fun.

[S2central.net]

We are talking about torque not power !!!
I want that 600Nm all the way across the Rev range. Torque translates to the cars ability to accelerate which is where the fun comes in and of course improved agility in competitive use. Power translates to maximum speed which is all fine wide open on the autobahn but not something you can use every day !

[Albert]

absolutry right !

Gearbox:- Audi RS2 Gearbox
Tyre:- 255/40/18
Change rpm: 7500

Top Speed in 1 gear = 64.981 KPH
And changes into 2 gear at 4050 RPM dropping 3450 RPM
Top Speed in 2 gear = 120.335 KPH
And changes into 3 gear at 5238 RPM dropping 2262 RPM
Top Speed in 3 gear = 172.298 KPH
And changes into 4 gear at 5852 RPM dropping 1648 RPM
Top Speed in 4 gear = 220.809 KPH
And changes into 5 gear at 6262 RPM dropping 1238 RPM
Top Speed in 5 gear = 264.457 KPH
And changes into 6 gear at 6192 RPM dropping 1308 RPM
Top Speed in 6 gear = 320.328 KPH

The power must be 5000-7500 or 4500-7000 depends how high you rev the engine

It is important how much power you have on wheels. Short - engine Nm x gearbox = power at wheels. It is much better to stay on lower gear and rev maximally high. It is not goot to have 650Nm at 4500 and 500Nm at 7000 rpm. It is "fun to drive" but the car is not fast. Better to have 550Nm all the power band (5000-7500).

[Quattronaut]

For short: at 7000rpm NMs=HP.

Good response is necessary for track use, yes- but setting the peak power too low in rpm band is not optimal IMHO, because you are normally revving the gears out due to the lower gear ratio. So power from 2500-6000 won´t make you to happy. After revving to 7200 and then change gear, you are around 5500 rounds, depending on which gear it was. In this range, torque ist going down. So you loose 2500 rpm of real torque.

I would set the peak power to around 7000rpm. With a good charger at 2,2L, boost then kicks in at around 4000 rpm, what fits better the profile of driving on race track, than an motor, that has torque from 2500 to 6000 rpm.

I´m just building up a 2,5L stroker with K26/27;
estimated:
1,5 bar/ 550NM @ 3000rpm
2,5 bar/ 750NM @ 3500 to 4500rpm
2,0 bar/ 540hp @ 6500rpm

I do not want to discuss this setup in here; but this IMO woul not be optimal for track, because peak power and max torque are too early in rpm band. With the same charger and 2,2L, both points should be 500-600 rpm higher, what fits track use much better.

[Thuppu]

So not much to worry about then. I assume all who wants 500hp, have done the clutch and rods. 01E takes 700Nm no problem, don't know if anyone have found the limit for the crank, 1xxxNm..? Propably the driveshafts isn't the problem either if you don't launch from zero.