k27#8 880hp? help plz

[red12]

Hello i wanted to know more information on the k27 turbocharger especially the k27#8?. My qestions are were can i find some legitimate questions on this turbocharger? like flow maps max hp it can handle etc.. The previous thread about the k27 one here helped a litte bit but not much. And i also here about k27/k26#5 hybrids.. Does anyone know how much hp the k27 can handle? ive heard anywere from 500hp-880hp! but dont know the truth because there are diffrent models of this turbo. i guess the #8 is the highest flowing k27 im confused . Im intrested in thsese turbochargers because they have great spooling characteristics from what i hear for such a large turbocharger.plz help and thank you for your time.

[Polygon]

I don't know anything about this turbo but I can tell you that horsepower gains will vary depending on the engine, exhaust, and intake.

[2turboimports]

i've heard a couple things about the k27-8....both were extremely variant from each other. one person said it sucked ass and lag was realy shitty. then another said it was badass, and lag was better than a t-66. the first was on a 2.5l 4 cylinder, the second on a supra.

[KC Ron Carter]

KKK27 was OE on 80's BMW 745i Turbo car.

Here is a 600 HP model.

http://www.viinikellari.com/745/performance.htm

He is the m102 guru who built Tuoma Perfection Turbo Upgrade.

On an engine with 500.000 km +
Test conditions:
Fuel: 98 octane unleaded (with lead substitutes)
Ambient temperature: 8 degrees celcius
Turbo boost: 1.1 bar (16 PSI)
Gear: 3rd (40 km/h at 1000 RPM)
RPM range used: From 1600 to 5250 rpm (210 km/h)


The known limitation is the exhaust system. The standard exhaust can not handle all that power so some of it was lost in the pipe due to resistance and back boost. How much was it we don't know exactly, but a good guess is some 40-50 hp (a bit over 10% of total power). We assume that with proper exhaust system these tests might have given some 450 hp at 1.1 bar. New exhaust has already been designed and we know that it can handle min. 500 hp.

We run the engine also at 1.5 bar boost and everything worked well for a very short time we tried it. The turbo, wastegate and chip were able to handle that, but the the fuel system could not.

At ALL power levers we recommend to use
1) A 3 or 4 wire o2 sensor and a mixture monitor such as the HALMETER AFR30 ( http://www.halmeter.com/ )
2) Cartech Rising Rate Fuel Pressure Regulator ( http://www.cartech.net/ )

Interesting point is also that the best power and torque are at fairly low rpms. That gives the opportunity to move those up by changing the camshaft to steeper version. That would further increase the max power quite a bit. Torque would go down in low revs, but that does not matter as it is unbelievable high anyway (you will see it in the curves).

Summary:
Assuming that the 50 hp/0.2 bar ratio is correct all the way from 0.9 bar to 1.5 bar we can estimate the maximum available power from 745 3.4 l engine as follows:

1. Standard engine/exhaust/fuel supply with Motronic chip upgrade and boost control modification
400 hp at 1.1 bar (maximum constant power)

2. Standard engine/fuel supply with chip/wastegate mod and 2.5"exhaust system
450 hp at 1.1 bar with Cartech Rising Rate Fuel Pressure Regulator. (Extra fuel injectors or may be needed for this power)

3. Standard engine with chip/wastegate mod + 2.5" exhaust system + Cartech Rising Rate Fuel Pressure Regulator + add-on fuel injectors
550 hp at 1.5 bar

4. As no3 but with steeper camshaft
600 hp at 1.5 bar

This is 16 psi or 1.1 bar



Later,

[Polygon]

Originally Posted by 2turboimports

i've heard a couple things about the k27-8....both were extremely variant from each other. one person said it sucked ass and lag was realy shitty. then another said it was badass, and lag was better than a t-66. the first was on a 2.5l 4 cylinder, the second on a supra.

There is the problem. If it is big enough to compare to a T66 then I would say it is not the right turbo to be installed on a 2.5L engine. It is just too small. He was right though, it probably had shitty lag, but that is because his engine is too small and he didn't have good airflow for such a big turbo. The Supra on the other hand, does.

[red12]

very true but with todays technology people are putting ceramic ball bearing t72-76 turbochargers on street driven four bangers and dont complain at at all. heck look at the garret gt35r 700hp turbo but spools quicker than a t3/t4! thats no bull shit either. ball bearing turbos have 50% less lag than conventinal thrust bearing turbos.