Rb26 Turbo Comparision Graph (from Latest Hpi Mag)

[Roy]

and also Ash i havent personally seen any hks vs garrett at 2 bar plus but going by every other garrett vs hks turbos, the garretts just dont produce much more power from 25-26psi onwards. also your point on going from 16psi to 25psi and making a huge difference is right, but try winding it from 25psi upto 28-30psi and see if u make any more power at all????

The whole Garret suck at high boost pressures and the HKS are better thing has me a little perplexed. I suppose you need to make the distinction with regards to tyeh fuel used etc?

But sayign that Garretts typically wont make power once the boost levels get up there? Well i sit and think of all the turbo cars that have been raced the past 18 or so years with decent enough injection and turbos etc. And i stop and think how many have used HKS or other Jap turbos. Even the race Nissan / Toyotas etc dont use HKS etc. Surely if they were superior they would homologate them isntead?

And of course lookign at race cars is always difficult as they run restrictors etc etc, plus there is also the fuels etc they are allowed to run...but two examples of turbo cars usign Garretts at high boost:

Nissan Skyline GTR LM (1996)

Engine configurations – inline 6 RB28DETT

Displacement - 2795cc

Turbo/s – 2 x Garret turbochargers

Inlet Restrictors – twin 41.0mm

Hp – 600hp @ 7,500rpm (2.4bar)

Weight – 1282kg

Essentially a modified JGTC car the LM GTR RWD, dry sumped and stroked which allowed the crankshaft centreline to be dropped 30mm, the engine was also moved 30mm further rearward. They used 5 speed H-gate boxes as losing a gear in a sequential box would have the car out of the race as was the case in 1995, but in H-gate box would allow the car to limp on. The car used 4-spot AP Racing carbon fibre brakes.

Two cars were entered by the factory NISMO division, with one car being the epitome of reliability all through qualifying and the race up until the 23rd hour when a driveline vibration was detected. The gearbox and propshaft were repalced in 34minutes with the car going on to finsih, the second car suffered a brake failure and crashed out of the race.

Toyota Celica – Millen Pikes Peak Car

Engine configurations – inline 4cylinder 3SGTE

Displacement – 2.14L, 89 x 86mm

Turbo/s – 1 x Garret turbocharger, with external gate and 60mm compressor

Inlet Restrictors – free

Hp – 930hp @ 8,900rpm (4.06bar) at sea level. 600lb.ft between 5,000-5,500rpm

Weight – 1134kg

Don’t ask me the sort of fuel or compression ratio this thing runs, as I havent been able to find out, but the Garret turbo seems to be efficient at that boost level. The Celica uses a 5-speed non-synchro box which drives the front/rear wheels with a 50/50 torque split. AP 4-piston calipers grip 304 x 27mm front rotors and 276 x 23mm rears. The body is moulded glass fibre replica of the production ST205 shell, with the floor being formed by carbonfibre/aluminium honeycomb underwings front & rear, with the rear incorporating ground effects tunnels from the centre of the car rearwards.

So looking at race cars that use turbos, why are IHI, KKK and Garrett used rather then HKS/Trust etc?

[CruiseLiner]

The whole Garret suck at high boost pressures and the HKS are better thing has me a little perplexed. I suppose you need to make the distinction with regards to tyeh fuel used etc?

But sayign that Garretts typically wont make power once the boost levels get up there? Well i sit and think of all the turbo cars that have been raced the past 18 or so years with decent enough injection and turbos etc. And i stop and think how many have used HKS or other Jap turbos. Even the race Nissan / Toyotas etc dont use HKS etc. Surely if they were superior they would homologate them isntead?

And of course lookign at race cars is always difficult as they run restrictors etc etc, plus there is also the fuels etc they are allowed to run...but two examples of turbo cars usign Garretts at high boost:

Nissan Skyline GTR LM (1996)

Engine configurations – inline 6 RB28DETT

Displacement - 2795cc

Turbo/s – 2 x Garret turbochargers

Inlet Restrictors – twin 41.0mm

Hp – 600hp @ 7,500rpm (2.4bar)

Weight – 1282kg

Essentially a modified JGTC car the LM GTR RWD, dry sumped and stroked which allowed the crankshaft centreline to be dropped 30mm, the engine was also moved 30mm further rearward. They used 5 speed H-gate boxes as losing a gear in a sequential box would have the car out of the race as was the case in 1995, but in H-gate box would allow the car to limp on. The car used 4-spot AP Racing carbon fibre brakes.

Two cars were entered by the factory NISMO division, with one car being the epitome of reliability all through qualifying and the race up until the 23rd hour when a driveline vibration was detected. The gearbox and propshaft were repalced in 34minutes with the car going on to finsih, the second car suffered a brake failure and crashed out of the race.

Toyota Celica – Millen Pikes Peak Car

Engine configurations – inline 4cylinder 3SGTE

Displacement – 2.14L, 89 x 86mm

Turbo/s – 1 x Garret turbocharger, with external gate and 60mm compressor

Inlet Restrictors – free

Hp – 930hp @ 8,900rpm (4.06bar) at sea level. 600lb.ft between 5,000-5,500rpm

Weight – 1134kg

Don’t ask me the sort of fuel or compression ratio this thing runs, as I havent been able to find out, but the Garret turbo seems to be efficient at that boost level. The Celica uses a 5-speed non-synchro box which drives the front/rear wheels with a 50/50 torque split. AP 4-piston calipers grip 304 x 27mm front rotors and 276 x 23mm rears. The body is moulded glass fibre replica of the production ST205 shell, with the floor being formed by carbonfibre/aluminium honeycomb underwings front & rear, with the rear incorporating ground effects tunnels from the centre of the car rearwards.

So looking at race cars that use turbos, why are IHI, KKK and Garrett used rather then HKS/Trust etc?

good point, but when u look at that pikes peak car making 930hp it needs 4 bar boost??? thats pretty bloody bad for that power isnt it or am i missing something

[Guest Mashrock]

So at the end of the day, what you really need is your whole head, inlet and exhaust matched up with your turbos or turbo and you should be a happy camper,

with as little restriction as possible without going too far??

[Busky2k]

Well it is 2L. You're not going to get 900hp with 2 bar or something ridiculous.

To say HKS are more efficient at higher boost, you need side by side compressor maps to make that claim.

Edited June 19, 2006 by Busky2k

[Guest Mashrock]

p.s. thats pretty sweet power comming form a 4 banger.

reminds me of group b rally cars. f**k were they running some puff

[Roy]

good point, but when u look at that pikes peak car making 930hp it needs 4 bar boost??? thats pretty bloody bad for that power isnt it or am i missing something

Yeh could be prety bad...but i think its more a fact that they run that sort of boost, then they must be able to do so safely and must be making more power, otherwise why bother? Oh and the thing only has a 60mm diam compressor, so 930hp is pretty friggin great

[CruiseLiner]

Yeh could be prety bad...but i think its more a fact that they run that sort of boost, then they must be able to do so safely and must be making more power, otherwise why bother? Oh and the thing only has a 60mm diam compressor, so 930hp is pretty friggin great

maybe hks dont make something suitable for 930hp on a 2L without huge lag issues, so they designed their own turbo with custom wheels etc to make it more responsive but still capable of making 900hp and running a massive amount of boost without failing. i dont think any hks turbo will run 4 bar for long would it?

that engine and turbo must be rebuilt fairly often going by those numbers and a small compresser as well.

great efford none the less, i just didnt understand the insane boost level (56psi+)

[paulr33]

>So looking at race cars that use turbos, why are IHI, KKK and Garrett used rather then HKS/Trust etc?

i would expect it would come down to bearing types, compressor options and also compressor maps. without a compressor map the turbo is a bit of an unknown and offers no benefit for a race team. why go with something unknown when you can select everything you need from a map

[Roy]

Well thats the strange thing...if BB turbos were really that superior why are KKK so well received? And for the life of me i dotn think any manufacturer would be using a turbo based on the compressor map alone. They have dynos that simulate loads etc from various tracks, ambient and barometirc conditions.

They would be able to collate all the data they need, and if the wheels and housign combinaitons where to their requirements then surely that would be homolgated?

Im keen to see the articles on the LM winning Audis over the next few months...interesting to see the setup they used, KKK or IHI?

[Roy]

Well that was surprisingly easy...normally i have to read crap loads to find the brand of turb used...

Preparation Audi Sport

Type: V12 TDI à 90° alu

Position: Longitudinal central AR, porteur

Valve gear: Double ACT, 4 soupapes par cylindre

Supply: Injection directe TDI

Ignition: Bosch Motronic MS14

Boosting: 2 TURBOS GARRETT

Engine torque: 1100 Nm 3500 RPM

Horsepower 650 hp 4500 RPM

Restriction: 2 brides dia. 39,9mm

[Guest Mashrock]

mmmm direct injection diesel..

[2rismo]

Hp – 930hp @ 8,900rpm (4.06bar) at sea level. 600lb.ft between 5,000-5,500rpm

It's not 4.06 bar @ racing altitude though is it??!?!

It's something called 'normalising' - using a turbocharger to regain lost power from running/racing at altitude as opposed to just gaining power. Imagine how little density there is where these cars are racing compared with sea level.

Just a thought.

Adrian

[2rismo]

Also, what turbos do the diesels in tractor pulls use? Big turbo blowing through a small turbo to make in excess of 150psi in some cases!

10.0 Bar!?!?!?

Adrian

[shanef]

Also, what turbos do the diesels in tractor pulls use? Big turbo blowing through a small turbo to make in excess of 150psi in some cases!

10.0 Bar!?!?!?

Adrian

Excuse me?

That's massive...i use to have photo's of a 'drag' tractor launching off the line and splitting the BLOCK clean in half

[m&m]

i think i'll probaly end up goin the 2530 low mounts.. how ever.. im not a gtr.. but i know dirt garage's results were on race fuel n all that.. but hell.. someone post up a dyno sheet of 2530's being push to there limits on pump fuel than compare them to magazine comparision.. would be very very interesting to see

Stock crank,rods,pistons,oil pump and head gasket,98 octane,22 psi,rwkw.HKS step 1 cams.

Currently being rebuilt with Tomei rods,Arias pistons,Jun oil pump,Tomei head gasket.

Deciding on turbo upgrade,leaning towards T88-38GK.One extreme to the other.

[Sydneykid]

Well thats the strange thing...if BB turbos were really that superior why are KKK so well received?

..................

Im keen to see the articles on the LM winning Audis over the next few months...interesting to see the setup they used, KKK or IHI?

KKK turbos are made in Germany. Audi, BMW, Porsche, VW are German car manufacturers, so they use the local product. The German speaking KKK turbo enginneers live at the car factory for months working with the manufacturer to make sure they get exactly what they want. KKK turbos and Porsche have a technology sharing and supply agreement that dates back to the 70's. The Audi agreement dates back to the original Quattro rally cars of the 80's. Audi is owned by VW, etc etc.

In summary it's one big happy krautfest, they aren't going to let some American/Japanese company get their foot in the door.

cheers

[Roy]

Yeh maybe. But i still say that its easy to come to the conclusion that if there was a major difference with regards to performance, either they would use a ball bearign turbo from another supplier...or KKK would just go and build on themselves.

[discopotato03]

LOL the Le Mans Audi R8 uses a pair of Garrett TR30R competition specific BB turbos . As far as I can tell most WRC specials also use the TR30R . Very very expensive made from unobtaneum materials to be light and compact . The few pics I've seen show 5/10 bladed compressors machined from a billet on 5 axis CNC mill . The turbine I believe is the 60mm version of the NS111 found in 54mm form in high performance GT28BB turbos . The turbine housing is thin walled metalic though I think I heard mention of some space age composite being used at times .

Tractor pulling , generally compound or multiple turbos in series - even dinosaur types can generate very high boost pressures without damaging themselves . Intercooling between the turbos helps lots with charge density ! Diesels cope far better with high boost pressure because of the compression ignition process . They suffer more from running rich than lean .

Garrett Japan make turbos for HKS - well the cartridge anyway . This is why if you buy a TO4Z or one variation of the GT30R/GT3037 you are getting the same cartridge . If HKS can't get Garrett housings to suit an application they get their own made . Garrett do sell certain wheel combinations/trims exclusively to HKS . For example the GT3037/GT30R can be had from HKS in 48/52/56 comp trim but Garrett only market the 56T . HKS market the T51R BB in 76 turbine trim but Garrett will only sell you a GT42R (same family wheels) with an 84 trim turbine . Funny how some of HKS's products are better responding in certain situations isn't it , particularly when your paying more for less . Marketing ...

Cheers A .

[T04GTR]

indeed.

the main diferance i believe is basicly just the housings. they seem to be better designed for high boost aplications i think.

but... i dont know about you i dont really wanna be running around on 2 bar boost. especally when its waring out stuff alot quicker than on the nice 1.2 bar setting.

rebuilding/freshening up a rb26 isnt something i wanna do every 6 months lol

[T04GTR]

garrett single ftw