KKK turbo VS GT series 30-35

[mb911]

I am curious what folks opionion of the new kkk turbos are vs the gt series garretts are. can any one post pluses and minus's ITHO . I have wondered this for a while though I tend to like the new triple k varients I was looking for impartial response's

[beepbeep]

Which new KKK's? New ones are small frame turbos for twin-turbo or single turbo small-capacity engines. The one from Volvo S60R is probably biggest new KKK which could still be used on semi-optimal way on 3.3L engine. K26's are too small and K27 haven't (to my knowledge) evolved last 20 years. Most of large-frame KKK's on market are hybrids using Garrett cold side and KKK hot side.

I would say GT35BB is probably unmatched by KKK turbo of that size. Only thing that prevents people from bolting on Garrett's is different flange and oiling requirements.

For OEM installation, it's a different story. But for ultimate power...I would chose Garrett. Good documentation and compressor maps help as well. KKK seems to be more involved in OEM applications and Garrett is going extra mile to please the performance public.

[mb911]

Originally Posted by beepbeep

Which new KKK's? New ones are small frame turbos for twin-turbo or single turbo small-capacity engines. The one from Volvo S60R is probably biggest new KKK which could still be used on semi-optimal way on 3.3L engine. K26's are too small and K27 haven't (to my knowledge) evolved last 20 years. Most of large-frame KKK's on market are hybrids using Garrett cold side and KKK hot side.

I would say GT35BB is probably unmatched by KKK turbo of that size. Only thing that prevents people from bolting on Garrett's is different flange and oiling requirements.

For OEM installation, it's a different story. But for ultimate power...I would chose Garrett. Good documentation and compressor maps help as well. KKK seems to be more involved in OEM applications and Garrett is going extra mile to please the performance public.

I am thinking specific to the zero clearance hi flow's from ultimate etc as they are well built turbo's using the k27 chassis

[beepbeep]

I'm very sceptic to "zero clearance hi flow extra ultra ultimate superpower 2000" turbochargers which have been "enchanced" by small companies.

Equipment to measure efficiency and properly map a turbocharger costs more than total yearly turnaround of many of those companies.

With other words, as "zero clearance hi flow ultra infra" turbo that doesn't have a verified turbo map its unverified. Most of the times, "modifications" are unscientific...like clipping the wings (makes surge line go up but it decreases the efficiency) or making grooves into turbo compressor intake that look fancy but have no proven value.

With that in mind, I would chose OEM Garrett turbo with published turbo map any day of the week. Also, KKK don't have any BB-cartriges either.

[mb911]

Originally Posted by beepbeep

I'm very sceptic to "zero clearance hi flow extra ultra ultimate superpower 2000" turbochargers which have been "enchanced" by small companies.

Equipment to measure efficiency and properly map a turbocharger costs more than total yearly turnaround of many of those companies.

With other words, as "zero clearance hi flow ultra infra" turbo that doesn't have a verified turbo map its unverified. Most of the times, "modifications" are unscientific...like clipping the wings (makes surge line go up but it decreases the efficiency) or making grooves into turbo compressor intake that look fancy but have no proven value.

With that in mind, I would chose OEM Garrett turbo with published turbo map any day of the week. Also, KKK don't have any BB-cartriges either.

OK so what specific gt series would you suggest for for your average 350hp 930 or turbo conversion? I am suprised no one else spoke up yet

[lucittm]

I asked a local turbo rebuilder almost the same question you pose. He said that the reason KKK's have not changed much is that they are a good design that is hard to improve upon. He said the ball-bearing turbos don't last as long or perform as well, all else being equal.

Mark

[hobieboy]

I have the original K27HF from Kevin and I am actually considering moving to a Garrett.

I have never really driven a stock 930 or other K27's but I can say with the HF I have, boost comes on very progressively. I never felt I got the on/off switch effect.

My reason for change: I am changing CAMs because I need more top end for the track (SC doesn't work well - my power/torque is done ~5500rpm). While I'm at it & from talking to a few vendors, everyone suggests that the GT35r will flow more than the K27; hence my temptation to try.

I am just starting this process, but the downside I can see - cooling. Its more complex because of the water jacket requirement.

[mb911]

I sell a fair amount of gt30-or 35's only as service for my customers (not to make much money as Buy them from a dealer not direct)but never really got any feedback as to which way is better for street cars. I like that kevin is a porsche guy and that surely helps in the decision for most. What a/r's are you guys finding to be the best combo's etc?

[930gt-40r]

I got a dual ball bearing pt67 from precision (basically a GT-37) and I am running a .81 A/R hot side on mine. I have a boost creep problem that I hope to solve with some boost reference modification, but the turbo pulls hard after 3800 all the way up - especially when it creeps to 25 pounds

[mb911]

I am thinking most like the 2k range for full boost or close to that for our cars. Also I have a feeling the kkk is a more robust turbo in this application but can anyone speak to that? Just curious really

[crimson ghost]

2k RPM full boost with a gt30-or 35 ???? What size motor ???

[911st]

Ben.

My understanding is the K27 turbos are more reliable and designed for our air cooled cars but they take a significant supply of oil to keep the bearings cool.

The GT's and others offer more design flexibility with many more wheel choices and they are were originally designed for watter cooling. I suspect the ball bearing style cartridge may reduce the cooling requirement so some degree. The plus for a retrofit is they do not require the oil flow the KKK dose.

Thus, though there are lots of reports with the non KKK's living a long life on a 911 motor, the KKK might be a more durable choice over the long run.

For a 911 motor making about 350 HP the K27-7200 is a near perfect fit. Especially for CIS cars as it matches the fuel deliver potental very well. It has the right size hot side and the compressor is well matched so it comes in fast & hard and dose not get soft on boost until the higher 300's HP.

The HF and K29's typically keep the 7200's hot side (7006 hot side for track cars) and put a bigger compressor wheel with it. They can start boost earlier as the compressor moves more air faster. However, because of the change if the leverage or ratio between the hot an cold side, it takes a longer duration to reach full boost. This dose not mean it will reach full boost later than a K27-7200, it just takes longer from boost onset to say 1 bar. With the bigger compressor wheel it can support over Hp in the high 300's and even well over 400hp with out boost falling off.

On my old C2 3.3 Turbo the HF turbo seemed more civil and came up on boost in a way it felt more like a big normally asperated motor. I ended having issues with it and went back to a K27-7200 and it came in much harder and faster which more fit my style.

The issue with the HF and K29's that use the K27-7200 hot side is at the higher HP level they acces, there becomes a need to vent more exaust out the Wast-Gate circut. With most of the 930 type exausts the WG circut is close to being at its limit and this can result in boost creap. I had to to go to a .7 bar WG spring because of my B&B style headers and the biger turbo and I still saw 1 bar in the higher rpms.

Your HE's with twin WG's should be a soulition to the overboost problem. However, for a track car it is better to just go to a larger hot side turbo and live with the higher boost onset.

[mb911]

For my application the KKk makes more sense as I can prototype easier with a stock build up but 911ST I think you are right on there I think that the GT's are a bit more fragile on our cars but some have made them work great.

Let have some more input guys keep it up. I really wish we could find someone that has run both on their current setups with some real life comparison

[gogomobil]

Why not simply use a K27 7006 turbo?
Better than the 7200, fully compatible and will not loose its punch after 5500rpm.
Should be good for around 400hp.
I want to replace my 7200 and I think I will go the 7006 route.
A turbocar should not feel like a N/A car IMHO, thats why I dont like the HF turbos.
I like the way the 7200 kicks in, but sadly it gets weaker after 5500rpm.
After getting used to the power the 7006 delivers I might switch to a BB Garrett turbo which is more complicated to install, maybe.

[mb911]

keep in mind I am using all opinions for reference so thanks please keep the info coming

[911st]

Originally Posted by gogomobil

Why not simply use a K27 7006 turbo?
Better than the 7200, fully compatible and will not loose its punch after 5500rpm.
Should be good for around 400hp.
I want to replace my 7200 and I think I will go the 7006 route.
A turbocar should not feel like a N/A car IMHO, thats why I don't like the HF turbos.
I like the way the 7200 kicks in, but sadly it gets weaker after 5500rpm.
After getting used to the power the 7006 delivers I might switch to a BB Garrett turbo which is more complicated to install, maybe.

That is a great track turbo. Andial and Porsche used in on there 92 C2 race car.

I believe the 7006 is basically a K27-7200 compressor with a larger hot housing and builds less back pressure in the exhaust manifold. Full boost comes in on a 930 more like 35-3600 rpm than the 3200 if i remember but holds better to red line. For over 400hp one can benefit from a bigger compressor wheel which is the K29 and HF's bread and butter. Put a K27-7006 hot side with a bigger compressor wheel and you have a monster track turbo.

If you can make a 930 breath more easialy with cams, porting, and low restriction exhaust one can just about stretch the K27-7200 to 400hp some have clamed but boost will fall off which is ok if you do not have a good fueling strategy. 360-380 is more like it if I remember correctly.

I defer to the experts.

[David]

The Garrett is so different from the K27 that it seems the only time worth using the Garrett is when you need the flow of a GT37 or larger for an EFI set up.

The K27 looks like a better made, more reliable turbo so that's what I'm using, but I'm using a K27HF2 so if I want more power I'd have to go Garrett.

[930gt-40r]

Originally Posted by 911st

Your HE's with twin WG's should be a soulition to the overboost problem. However, for a track car it is better to just go to a larger hot side turbo and live with the higher boost onset.

Agreed, I am just trying to spare taking them off again and having to buy another V44 Tial gate for $300.
I would love to try a larger hot side but it would suck on the street. (does anyone know what a Supra guy would run for a Gt-37r hot side???)

What is the highest hp number anyone has gotten with a 35R on pump fuel?

[beepbeep]

Originally Posted by mb911

OK so what specific gt series would you suggest for for your average 350hp 930 or turbo conversion? I am suprised no one else spoke up yet

For 350hp and very fast spoolup and low boost treshold, optimal turbo would be GT30R.

[WERK I]

I was able to find a map of the K-27 on the internet. Unfortunately, I can't tell if it's a 7006, 11.11 7006 or 7200. My guess.....K-27 7200. It's the most popular and has wider application use. Beepbeep, 911st, you're very close to being on the money for HP capacity. I was thinking 450BHP range, bummer.