Pat Kennedy

Just curious if anyone has any real world experience with these. Lindsey Bros. says they are the best BAR NONE! Pretty big statement. They have both a Stage 1 and a Stage 5. Anybody seen any compressor maps or concrete data on these things?

Twinspool

I donno, I'm partial to Garrett just because they are water and oil cooled and Kokeln is just oil. Maybe it makes no difference but any time I can keep the oil cooler I will.

Silverbullet951

What are the Hp numbers on the cars with those turbos? Are there any cars with a kokeln turbo installed?

kellyk

Got to tell you that the Kokeln turbo's are great! I am using one on my 3.0 liter 951 and have had no problems. If you are serious about driving your car you don't want a water cooled turbo as it only suceeds in boiling your coolant. Kokeln has a great history of testing their parts to death before they ever sell them to a customer. Everyone on the west coast can tell you that the Vision/Kokeln 951 "Flipper" is one of the fastest and most reliable Porsche race cars around.

Silverbullet951

Thanks kelly, I guess that explains it.

Ski

I've got the stage V with my car. Boost hits around 3000 to 3200. The car feels great and I've backed the boost back down to 15psi instead of 17. Hopefully going to the dyno tomorrow or Friday. I expect 325 to 340 at the rear with boost back to 17. I may bea bit shy of the "363 hp" as I did not get the cam; I opted for ported and polished head.

My car is not a daily driver. I change the oil every 2500 miles and I've installed an aftermarket oil cooler. I let it idle down about 20-30 seconds before shutting the car down. Just my opinion, if your car is a daily driver, city traffic etc..I would probably stick with a water cooled jacketed turbo. If not, I don't think it matters.

TurboTim

Water is one of the best heat dissipators known to man. This is why we use it for cooling engine blocks and turbos. Removing the watercooling on the turbos is not the greatest idea. Ask people who have done this for 6 months, a year or more and see how well their turbos are holding up. I can bet you they are not holding up as well as the same turbo with watercooling.All SFR turbos are watercooled and we do have access to the same turbos as Kokeln but we choose not to use them becasue I refuse to just use oil to cool a turbo that sees in exceess of 1500F.

Danno

I guess without water-cooling, you could get one of those turbo-timers like the ricers and have your car idle for 2-5 minutes after you turn it off to make sure enough oil has circulated around to make sure the turbo's been cooled enough. Still seems like a step backwards removing the water-cooling since it's oil-temperatures that's the problem at the track, not water. In fact, last August when I was at Willow Springs, it was 115-degrees out! My water-temp never went above 2/3rds but my oil-temp was so high, I only had 3.5-bar of oil-pressure from the thinned-out oil.

KokelnRob

To add some clarification to the statements made about the Kokeln Turbo and turbo water-cooling…
The factory added water-cooling to the turbo on the 951 to help prevent the oil from “coking” or crystallizing in a hot turbo when the motor was shut down. A turbo water pump, separate from the main pump, runs coolant through the turbo once it reaches a set temperature and turns off once it has cooled. Under normal driving conditions where the turbo does not go above this set temperature the turbo pump will not run once the motor is shut off. Even under hard driving or race conditions, all that is needed is to take your cool down lap or if you’re on the freeway, drive normally once you take your exit.
Dwain has come across several situations where people have told him how important the water-cooling is and how much better their turbo runs because of it. Then when he goes to service the car, he finds that the previous mechanic neglected to drill the main water pump plate that leads to the turbo pump. (The N/A water pump plates do not have the orifice for the turbo pump drilled through, the 951 plates that cam pre-drilled have not been available for many years.) So the customer who can’t live without the water-cooling for the turbo has been driving without it since their water pump was replaced – in one instance for as much as 50,000 miles and they never felt the difference!
The factory turbo water pump system has at least 8 separate places where it can fail and they are difficult to get to. One of the first things we do when preparing a racecar is to get rid of the turbo water system.
As mentioned above, we test all of our products rigorously before they are released to the public. The whole reason behind Flipper is to purposely break it. That way we know for a fact what works and what, definitely, will not.

SamGrant951

so youre telling me some of us are driving around with the water cooling system not even working on our factory turbos?? (or did i mis-read)
this is a good thread, my eyes are open...

tazman

[quote]Originally posted by SamGrant951:
<strong>so youre telling me some of us are driving around with the water cooling system not even working on our factory turbos?? (or did i mis-read)
this is a good thread, my eyes are open...</strong><hr></blockquote>

After you shut your car off and you hear your turbo pump running listen around the coolant resivor for the water running into it. That will confirm that you have water running through your turbo.

GrantG

Rob - Your post makes sense. How many miles fo you expect from one of your turbos if a cool-down lap is taken?

-Grant

KokelnRob

We have yet to have a turbo fail due to overheating.
In testing on Flipper we purposely ran too small an exhaust housing to see how long it would last. We over-revved it and operated it at or beyond its surge limit quite a bit before it finally broke...150 race hours later. (Just a bit of bragging...Flipper has pulled a 1:23 at Willow Springs.)

Ski

Rob does speak the truth; when we pulled my "thermostat" for the turbo off the water pump to place the new Kokeln blank there, mine had not been drilled by the mechanic(dealership)either. This took place at 57,xxx and I bought the car at 68k. The water cooled jacket was created to give people who drive turbo cars but don't understand maintenance of turbos, the people who "rev" their car before shutting it down or don't change their oil at proper intervals,,,,it was built for them as a way to help them and to help sell the "turbo" car. Anyway,,I am very pleased the turbocharger, it's performance and Rob and Dwain taking my calls helping me to tune the system. Rob even sent me a set of injectors to try when all the time it was fuel pressure and the factory air meter setting. Good customer service there Rob! Going to the dyno Friday to check hp and A/F ratios, which are showing 12.5 to 12.1 on the readout at boost presently.

MachSchnell

Certainly I appreciate the cooling capabilities of the water cooled center section, but I have to question anyone who cites a lack of water cooling as a failure point...sure, bearings are prone to coking...of course, despite the nod to the 'ricers' which I find ridiculous regarding turbo timers, they were invented for a reason, and it had nothing to do with rice...much as Rob stated, and contrary to whoever quoted 2-5 minutes for run times, a turbo timer generally runs for 30sec or so, just like a cool down lap, and runs oil across the bearings to prevent coking...in addition, all you have to do is run synthetic, and the coking, even without a turbo timer, is virtually eliminated as the synthetic does not have that tendency. Think of the huge variety of turbocharged cars running oil cooled center sections, and point out to me any single one that fails as consistantly as the 951, especially the turbo itself (flame suit on)...sure, I love my Porsche, but referencing water cooling as the end all be all is silly. Sorry turbotim, I love the SFR offerings, but your turbo theory just doesn't hold water ;o) ...especially when all the wonderfully reliable turbocharged japanese cars are taken into account. Now, if Tim is referring to a water cooled center section like our k26 or k26/8 turbos, and you just take that water away, then sure, you may induce a failure point as you've removed a cooling source, but run a turbo designed for oil cooling only, especially a newer turbo (not some 70's relic) then it's built well enough that this shouldn't be a concern, particularly with the simple addition of a $75 turbo timer.

Sorry for the rant