Garrett or KKK turbo

Post by **mat_fenwick** » Mon Mar 24, 2008 10:40 am

I am carrying out a 1.9TD conversion (more details here http://www.bxclub.co.uk/forum/viewtopic.php?t=8409) and have to make a decision about which turbo to use...

The BX engine had the Garrett turbo, which obviously would fit straight onto the exhaust in the BX and I believe is regarded as the better unit. But, there is some oil present in the outlet pipe, so I think the turbo oil seals are not in great condition. The BX was smoking slightly on the overrun and more so on start up, which I had put down to valve stem seals - now I'm not so sure.
The KKK unit on the Xantia engine is drier (but still a trace of oil), looks like the outlet elbow will swap to mate up to the BX exhaust but when I drove the Xantia, seemed to have a louder whine under boost. Could that mean the turbo bearings are worn, or perhaps I should be more concerned about why the BX turbo didn't whine so much???
I'm planning to up the boost and fuelling slightly (perhaps 15psi?), but I'm not after a short lived out and out performance engine. It may be the Garrett is better if you are doing crazy things (Doc!) but the differences are marginal at the lower boost levels.

Could anyone shed any light on the above ramblings, or should I just toss a coin?

Vanny · Post by **Vanny** » Mon Mar 24, 2008 11:03 am

KKK is stronger (and can put out more boost than the block can take)

Garret will still get you plenty of boost, but is SOOOOOO much easier to adjust!

Personally i've always gone for KKK's (i have 4 of them in the garage) but i think there are more reasons fitting the Garret!

what intercooler are you thinking of?

AndersDK · Post by **AndersDK** » Mon Mar 24, 2008 11:33 am

I doubt you will see any oil leakage from the turbo.
On the cold (inlet) side the oil wil most definately have its origin from the sump vents which is connected to the inlet suction.

On the hot (exhaust) side any oil from the turbo will instantly evapourate to a white fog from you exhaust pipe, while oil from valve stem seals will take part in the combustion, thus making the exhaust a blue tint.

From members postings on several forums its not common for a turbo to leak small amounts of oil. They tend to go big problem rather suddenly emitting huge white clouds from the hot side, when this oil seal lets go.

They rarely if ever fails on the cold side. If they do the engine oil will be treated as fuel, and the engine will then do a run away - "quite fun"

Post by **mat_fenwick** » Mon Mar 24, 2008 12:53 pm

Thanks for the replies - that makes sense that it would be oil contamination from the breather system.

Vanny - are you meaning that the Garratt is much easier to adjust in situ? As both look equally easy to adjust out of the car!!! In fact the KKK looks easier as the linkage on the Garratt has corroded nicely! I was thinking of adjusting the boost slightly off the car, erring on the safe side, and hooking up a boost gauge once it's all back together (obviously adjusting the fuelling to suit). I read on another website (http://www.club-306.com/guides/306_turbo_tuning) that 2 turns on the KKK turbo is a good starting point.
As for an intercooler I will be using the standard one for the moment - I know that the position of it isn't great, but I'm not sure I can easily fit a front mounted intercooler with the air con condensor sitting in front of the rad. I am wondering about a scoop though if I can find a sutbtle one. (Not like this one!)

Jaba · Post by **Jaba** » Mon Mar 24, 2008 5:34 pm

Matt
Why not recon one of your turbos. It is an easy job. Kits are available on ebay in the 40 to 60GBP region.

I have just done one of mine and it is an easy job. I think the oil sealing was quite worn on mine. I had small amounts of blue smoke in the exhaust at slow speeds and throttle openings typically when going downhill. Like worn valve guides on a petrol motor. I could not see the smoke but a mate following me alerted me to the problem.
When I took the turbo out the compressor side had a lot of oil sitting in it. Which justified doing the recon to my mind.

Mines a Garret BTW.

Vanny · Post by **Vanny** » Mon Mar 24, 2008 6:43 pm

Garret, adjust the length of the bar between wastegate and turbo OR put a bleed into the pipe between wastegate and turbo.

KKK, remove pin, adjust nuts, reinsert pin and hope nothing moves in the process!

Garret is MUCH easier to adjust when it is on the car, the only time when adjustments can/should be made!

don't adjust it off the car as different applications have different boost setups to begin with (example the Xantia estate TD has less boost than a saloon, and the SD Xantia's have less again, but ALL use the same turbo!).

Buy a decent guage as well, ideally with a floating needle, makes a significant difference!

What pump are you using? Remember to up the fuel sufficently.

Post by **mat_fenwick** » Mon Mar 24, 2008 9:48 pm

So the KKK turbo on the Xantia engine may be set up for a different level of boost than the Garrett on the BX engine??? Meaning that the simplest swap would be leave the KKK turbo on the Xantia engine...

I take it that if I use the BX Garrrett turbo, I have to at least check that the fuelling is correct for the level of boost I will have.

The fuel pump is Bosch on the Xantia engine, I understand that's the simplest pump to alter the fuelling on.

DavidRutherford · Post by **DavidRutherford** » Mon Mar 24, 2008 10:58 pm

I'd use the Garrett unit. Not only do I think they are the better turbo, but the ease of adjustment when on the vehicle means it's the easiest to tune.

Garrett turbo and Bosch pump for easy tunability.. winning combination.

Post by **mat_fenwick** » Tue Mar 25, 2008 9:26 am

Thanks for the replies, looks like I will be using the BX Garrett turbo then.

John, I woudn't mind having a go rebuilding the turbo, but it would probably give me MORE worries than using one I know works. I know that they are simple devices really, but I don't have a workshop at the moment, so clean conditions are hard to come by...kitchen table???

Besides, from the oil in the pipes on the cold side of the turbo it seems to be from the breather system - it is on both the inlet and outlet sides.

Vanny · Post by **Vanny** » Tue Mar 25, 2008 1:20 pm

mat_fenwick wrote:
Besides, from the oil in the pipes on the cold side of the turbo it seems to be from the breather system - it is on both the inlet and outlet sides.

there is absolutely nothing to worry about, they all do that sir, they are designed that way!

Post by **docchevron** » Tue Mar 25, 2008 1:54 pm

What Daivd and Vanny said.
The Garrett is a better made and more easily tunable turbo.

It's possible to get stoopid amounts of boost from the Garrett and it doesn't seem to complain too much, where as KKK's dont like too much boost. I've killed three of them now, compared to only the one Garrett, and that was only because I asked alot more than was reasonable of the turbo in the first place.

I also modded the boost pipe so it's a matter of seconds to switch between MoT boost and Rest of the Year boost!