Porsche Enthusiasts Club Forum

I hate trying to identify KKK's, especially when they've been rebuilt. The number tallies to later 81- S2 motors.
You should have numbers on all the different turbo parts beginning with 5326 e.g.turbine and compressor housing. This sometimes helps.

The RoW/UK S2 turbos have the best compressor wheel out of the lot, the 2664 but have the smallest turbine housing, the number 4 size. These are still large by modern turbo standards.
It will be the compressor that holds you back when it begins to run off the other side of the map and turns into a high speed heat pump. Personally I wouldn't run one at more than 1bar boost and it would be wise to monitor EGT's with the number 4 turbine housing. You can swap to the number 6 if you can find an uncracked one. You'll have boost very low down with the number 4 and full engine management.
I would think 240-250hp is possible but I've never pushed the standard turbos that hard, always sticking to around 0.8bar.

AET are not that far from me in the Wakefield/Castleford area IIRC??
I've not used them but they do have a good reputation.

I've not looked into stiffer mounts for the snailshell but I bet they exist somewhere. Vibratechnics do stiffer fast road and race engine mounts. That's what I'll be running and Steve has them on his car.

ok well I found that number on the compressor housing which is a kkk part. but the exhaust side seems to be a new aet item, it has a small stamp in it aet0202, and then in the casting is 2280.

cheers

just had a very interesting conversation with aet turbos. they seem to be very clued up when it comes to kkk turbos, the chap knew about every option off the top of his head regarding turbine housings etc, s1/s2 spec turbos, and Carrera gt/gts setups. they can install a larger compressor wheel/machine the housing, and trim the blades to increase flow and hp potential, all for a very good price. they said 300bhp even on a 4 housing would be easy!

they confirmed my turbo is a stock rebuilt item with 4 housing

they also have some nice haltech management setups at a good price which are of interest to me, especially as I have a master mapper friend of haltech systems who I would really like to map the car once done.

today I have mostly been making a mess on the workshop floor, further stripping back components removed from the car.

where do the manifolds crack? I cant see any signs of cracks, just want to make sure im looking in the right place





old and new

That confirms what I was told, that they know their onions.
It's good to know they back up what I said about the 4 housing being relatively large. Compared to modern turbos it's definitely the compressor side that lets the old KKKs down.

Whether a modified KKK will compete with a KKK/Garrett hybrid or other modern options I don't know but if it makes the power efficiently and does it for significantly less then it's got to be worth going for.
930 Motorsport/9m/Ninemeister used to offer similar turbo options many moons ago when they were still interested in tuning the 931.
The turbine is relatively large for the size of the engine and OEM spec HP. Porsche have always been quite clever in how they spec the turbos IMO, even going back further.

As a further point Steve Bassington ran the number 4 turbine housing on his ridiculously fast race car to retain fast spool-up. If you're not running for ages on full power/full boost it's probably fine. During endurance racing the exhaust valves used to suffer and Porsche used a large turbine housing in an effort to reduce restriction and back pressure and keep EGT's sensible. This is probably not a problem for most of us running these engines. The large housing was also obviously to help outright flat-out power when competing against cars with much greater capacity and muscle.

I was pleasantly surprised to find someone so quickly that had such a good knowledge of the turbo in question. they also said they may be able to get me a new 6 or 8 housing!

when he asked what sort of power I was aiming for and I said I would be happy with 300bhp for the minute, he said that would be no problem, even with the 4 housing, and they could even trim the wheel to give me a certain power output at certain boost levels. I mentioned the stock cast pistons and not wanting to run to high boost on them, and he said they could increase the cfm output enough so that I could achieve 300 (ish hp) at only 1.1 bar or so!

im tempted to fit a set of forged pistons first time round and push it a bit.

Oh yeah, forgot about exhaust manifolds...
There are pics somewhere on 924board.org of cracked exhaust manifolds. Not all of them crack. My own was warped but still hadn't cracked and I have another spare that isn't cracked.

The manifold design is a problem but a lot of them crack for other reasons. The turbo support from my own car was alloy. When I removed it, it had a crack straight through it that otherwise could not be seen. This meant the manifold was taking more of the weight and had visibly warped front to back. The other turbo supports I have are all steel so maybe this was a revision by Porsche.
Furthermore it's common for the third turbo to manifold stud/bolt (the one you get to from beneath) to come loose and wind it's way out. They're all small details that don't help the situation.
The fact the manifold has different temperatures front to back and the mounting flanges have very little separation means a good recipe for cracks forming. Most common area is towards the turbo between 1 and 2 but they can crack anywhere.

Sounds good! I bet you've caught Steve's attention now you've mentioned the 8 housing.
The cast pistons do get slated a lot but I think a lot of it is down to people running higher boost and not considering the consequences or employing charge cooling. On top of that, a badly tuned CIS system/924 Turbo will make short work of them with detonation.

The stock parts will take a hammering if you know what you're doing and tune carefully with AFR/EGT monitoring etc.
The highest powered car I can think of right now that runs mainly stock parts is one in South Africa owned by Leonard Kruger.
He had the cast piston crowns ceramic coated IIRC. He shot-peened and lightened the stock rods and then modified them with locating dowels enabling him to fit larger rod bolts instead of trying to get special order ARP items.
He's another that welded a different turbo mounting flange to the stock exhaust manifold and uses a Garrett at up to 1.2bar making 330hp.
This engine also has ITB's and engine management with mechanical over boost and custom anti-lag... oh yeah and nitrous...

mine has a steel support. couldn't see any cracks anywhere but will inspect closer tomorrow.

another interesting thing aet told me was they have been dealing with kkk turbos for over 30 years, he then reeled off a list of race teams they supplied race spec custom turbos to back in the day. he said they can do pretty much anything with them.

was a good find!

starting to think about suspension setup, I will most likely fabricate a full custom front end setup, t45 tubular subframe, fully rosejointed, and tubular t45 lower arms. not only will it save a fair amount of weight, but rose joints will stiffen everything up, and keep geometry in line. on top of that it means adjustable track/camber etc so good amount of adjustment. its a pretty simple design, so will jig the original items and work from there.

we have done custom suspension setups/arms/subframes in the past for a few different cars so easy enough.

After reading this I could kick myself for not calling them in the past lol! I think KKK were the first manufacturer to get an F1 turbocharger to withstand 1000C.

Suspension plans sound awesome. Get that right and there'll be bugger-all that will touch you through the corners. Actually I would be interested in a pair of tubular lower arms (and I bet a good few of the turbo/NA lads in the 924 Owners Club would be).

One thing I've forgotten to mention properly is think carefully before you pull apart the bottom-end. The rod bolts are one use only then replace. Originals are NLA and the ARP are special order and need ordering in batches of minimum 5 sets, 10 sets preferably which gets the price down to around $210 PER SET IIRC.

In the past group buys have been organised by Ideola over on 924board.org. We could always put another message out to the UK club and also Ideola to try organising another group buy.

Alternatively, aftermarket steel rods with reusable ARP bolts can be sourced. The cheapest I've seen are the Crower ones that Ideola's Garage offers at around a $1000 plus tax/duty.

PM'd hours ago!!!

Lost out in buying a GTS turbo on ebay earlier this year. Think I bid circa £350 in the last few seconds when it was only £150 and it still wasn't enough to get it. Always people who want things more!!

But as you said Wes, fitting the 951S compressor wheel with give me a touch more head room with what I have. Here you go Nick, CGT spec K26 2660 6.10 with Zircotec coating on the turbine housing


Plus a Zircotec coated manifold


Oh, and a Zircotec coated modified front pipe


Lots more here http://porsche924.co.uk/forum/viewtopic.php?f=24&t=5421 but the mods have moved it to members only!

Steve, are you able to direct me towards some pictures of your interior, please? I have them saved somewhere but not on this machine and Im not able to log into the 924 club site, unfortunately.

Yours is ideal as the white tubing is very clear in pictures and Im trying to see where my own cage will fit relative to the seat and my head.


Simon

that zircotec coating looks very nice! i know its quite pricey though isnt it? what did you pay for those items to be coated?

bit more progress today. mainly removing more small parts from the shell, further stripping down parts removed from the shell etc.

i also started prepping some of the seams in the engine bay for welding. along with removing the black paint from the engine bay, as it had obviously been an afterthought by someone who rattle canned it, without any prep, and do was flaking. i will be painting the engine bay, and so need rid of this black flaky stuff otherwise the new coat will just do the same

i also picked off the nose panel, and removed all the panel work behind it, i will then be mounting a 951 intercooler, or possibly something larger, along with a big 951 radiator, and create ducting etc to both before re fitting the nose panel.

will be on the rollover jig soon!

will need to source intercooler and radiator to carry out front end fab work, and i will also likely be fitting a smaller aluminum fuel tank under the boot floor so i will be looking for one of these so i can start fab work on the rear end aswell.

Will you be replacing the 924 metal work with series two 944 panels? Certainly the easiest way to mount a 951 intercooler in my opinion.