K27hf ?

350HP930 · 03-22-2005, 05:22 PM

Well, as far as I know its a K27 7006 with the larger compressor turbine wheel from some other turbo like a garrett.

There isn't a lot of information going around on these things so I was wondering if anyone had any additional information on this hybrid that they could share?

strokher racing · 03-22-2005, 05:29 PM

They are based on a 7200....what do you want to know I owned one for a bit

Eric Hood

350HP930 · 03-22-2005, 05:46 PM

I am trying to figure out what my upgrade options are since I am planning on shooting for around 600 at the crank.

Perhaps its time to concider switching to a garrett instead but I want to know what the modified K27 is good for.

strokher racing · 03-22-2005, 05:52 PM

The HF has a custom wheel that is 60.40mm. It is good for around 550fwhp. There are other options out there. What is your foundation to get to 600hp?

350HP930 · 03-22-2005, 06:06 PM

Full width 750 CI intercooler, EFI, carrera manifold, headers, super cup cams, flame rings, 7.5:1 compression. Upper limit will be 600 but I will be happy ending up anywhere in the mid to high 500s.

strokher racing · 03-22-2005, 06:08 PM

How will you race the car? Where is the targeted boost range? Will you ever get the desire for more hp? What headers are you running

TimT · 03-22-2005, 06:11 PM

Heh I get it

K34 or K36

Give Bill a call, we are currently building a twin turbo K 29 street engine

350HP930 · 08:11 PM

Quote:

Originally posted by strokher racing
How will you race the car? Where is the targeted boost range? Will you ever get the desire for more hp? What headers are you running

Just auto-xes, DEs, and the occasional trip to the drag strip.

I would like to keep the 2500-6800 RPM 1 bar of boost I enjoyed with my K27 7006 but scramble boost on cool days might get as high as 1.4 bar.

I know I will desire more hp but between the relatively stock short block and 650 cc injectors 600 HP should be the theoretical limit.

350HP930 · 03-22-2005, 06:35 PM

I almost forgot, as far as headers go, I am running the following. The primary IDs are 1.5".

Brother · 03-22-2005, 06:40 PM

Warning**Warning**Warning

Possible dumb question...

Whats a flame ring?

strokher racing · 03-22-2005, 06:44 PM

look at the bottom of my head. See the groove? the cylinders are matched with a groove as well. A variety of materials are used to make the rings. they are primarily for high boost

Eric Hood

strokher racing · 03-22-2005, 06:50 PM

350...here are some turbos for you to look at http://www.precisionturbo.net/turbochargers.php

Do you have msn messenger? If you did we could exchange info more easily

Eric Hood

kenikh · 03-22-2005, 08:00 PM

Wouldn't it make more sense from a top end boost and lag perspective to go the 959 route and use progressive turbos or perhaps two smaller ones (one per cylinder bank). I can't imagine one turbo spooling up quickly enough to make the car tractable if blowing 600HP worth of air into the motor...

350HP930 · 03-22-2005, 08:22 PM

With the exception of slightly faster spool times twin turbos are over rated.

As long as you keep the hot side of the turbo small enough its not hard to keep the engine in boost when you need it.

I will need to check the exhaust dimensions of my K27 and see what I can find in the same ball park than can stretch the limits I am looking for.

Thanks for the link Eric, that resource will prove helpful for rough sizing, and then I will be on to the maps.

Too bad my K27 needs rebuilt or I could recoup a good part of a turbo upgrade.

strokher racing · 03-22-2005, 08:24 PM

Precision turbo is considered at the top of the game in racing turbos. They are very helpful. I have bought my injectors from them for several years. Everything from 72's to 165lb units

350 you have msn messenger?

350HP930 · 03-22-2005, 08:35 PM

Sorry, just yahoo and aol messenger.

beepbeep · 10:01 PM

Turbo flange on your header is made for twin-scroll turbo.

Why not go with Garret GT-unit and be done with it? Ball bearing cartridge will make it spool even quicker. GT35 or GT40 sounds like a good candidate.

Frankly, I don't really understand why Porsche-people insist on using KKK turbochargers (some of them pretty old designs) when there are better/modern units availabe. Must be some heritage thing...

strokher racing · 03-22-2005, 10:05 PM

The gt35 is not available in bb you will have to go with the gt35r to get ball bearing. The gt35r is good for around 700hp. The gt35 has a smaller compressor wheel but the AR is too big for a small motor so the gt35r would be a good choice. There is a big debate going on rennlist right now between a guy introducing the gt35r to the Porsche market in a bolt on deal, and the maker of the HF. He does not believe the gt series turbo will live in an air cooled engine.

350HP930 · 03-23-2005, 03:04 AM

Is anyone here using the GT-35? I am curious as to where one will start generating boost on a 3.3.

The last thing I want is a motor that doesn't start making boost till 4K RPM.

beepbeep · 03-23-2005, 04:27 AM

There is nothing that will shorten the life of GT-series turbo "on aircooled engine" that will make it live longer on watercooled one.

Aircooled engines tolerate less EGT than watercooled ones (due to thermal constrains) so in theory, turbochargers should last longer on 911 engines that on watercooled ones (pushing 900 deg. C EGT's in certain cases). Most bigger GT's are only oilcooled so there are no water-jackets anyway.

350HP:
You cannot both have the cake and eat it. big single turbo that flows 700hp worth of air will spool later than smaller one that supports 400hp. That's the way it is.

That being said, GT-series turbochargers are present "state of the art". Big KKK's are not. It's like buying expensive Mahle pistons when there are good custom made JE's to be had for half the price just beacuse "Porsche always used Mahle's".

GT32 and GT40 are available with plain bearings. GT35 is only available as R-option and GT40 can be had in both, as far as I remember.

It's your call.