Andrew 996TTS

I am in the process of rebuilding a 993TT project car and I heard this morning from my turbo shop that both of my standard K16 Turbo's need complete rebuilds. Apparently one had water through it and the other had a mouse living in it (the exhaust was removed from the car and it sat around for a while before I bought it).

I am being qouted around $2000US for complete rebuilds and around $3500US for new stock K16s (pricing in UK is crazy at moment, rest of my parts have come from US)

I have read everything I can find online and the consensus over here seems to rate the upgrades in the following order of desirability:

1. K 16 stock
2. K16/24 Hybrid
3. K16/16g
4 K16/26
5. K24/26

I am not sure where K24 stock fits in (as fitted to the GT originally)

I will never track the car and the only other upgrades I have gone with in the engine rebuild were for stronger racing timing chains, ARP rod bolt kit and 964
Cam sprockets to replace the 993 ones. Apparently the ECU has had a Roock Upgrade but as the rebuild is still happening I cant completely confirm this. Other than that the car is stock.

I am planning on sourcing a new (or rebuilt set) of turbos over in the US and was pondering whether to upgrade at the same time as the pricing does not seem much different.

Any suggestions on:

1. Whether I should upgrage at all or stick with the stock K16s ?
2. Where stock K24 fits in the list above ?
3. If I should upgrade what upgrade I should go for ?
4. Anyone I should avoid dealing with especially as I am buying blind from the UK ? (probably best to pm me with any of these)
5. Whether I need to update anything else at the same time or can simply bolt on the new turbos and away we go (stupid question I know) ?

I think at least the last two options on my list above are probably a bit extreme for my street use and I assume would also require additional mods to make them work properly (and reduce my engine/gearbox life as well I suppose)

Any help appreciated

Thanks,

A.

Spartan

Alot of this depends on how you use the car, what kind of power you want, budget, and the tuner you want to go with. Most off the shelf tunes (GIAC, FVD, oem 450 pkg, etc) will limit your turbo selection to the basic K16/24 or K24's. I always recommend hybrids with protomotive software where K16/16g's or K24/18gs are the way to go.

I've got a brand new set of K24's for sale for $4k if your interested, was going to go with a new setup this winter but decided to stick with what I have (K24/18g's).

No matter what DO NOT put stock k16's or K24's in there as it just a waste. Hybrids are a cost effective upgrade that yields substantial power increases but just make sure you don't get robbed and pay $3k+ for upgrades on top of the cost for donor turbos

Rassel

It's a long time since I looked into this in details and I can assure you there are some great posts in the 993TT board with the details of powerbands and upgrade options here. So search truly is your friend.

To answer your questions:
1. Since you already modified the car a bit, I don't see the point to keep it "original". If so, the K16 that the car came with where nice in the 90's. But there are better, updated and upgraded solutions now.
2. Stock K24 are just as stock K16. A bit outdated.
3. Decide how much you want to put into your upgrade. Bigger/different turbos will require more and more modifications than just the turbo. Next step would probably be an improvement of the exhaust and the step after that is to start doing internals on the engine.
4. Regarding choice of tuners. Protomotive and UMW seems to get good reviews on both technical competence and customer service on this board.

Good Luck!

Basal Skull

The other theme in general is not to get a mish mash of parts and go with a system ie. turbos, ecu, exhaust that are designed to work together. If your roock ecu is designed for K16s, it is not going to be optimized for brand x hybrids, brand y exhaust...

Basal Skull

Also with more power, you'll be making more heat and I would get more oil cooling.

Texas993

^^^^ All good advice.

I suggest that you talk with Kevin at Ultmate. He is the 993 turbo guru. And he help source me with an excellent clutch/LWF set up.

If you don't know about Kevin, look at the sticky thread in this forum about turbos.

Andrew 996TTS

Thanks for the help, will make sure I call Kevin.

Sanhi

Please let us now what you're deciding. I'm in the same boat. Want to replace the stock K16 with something modern. Not sure to stick with original K16 or K24 or go for hybrid.

Sander

Spartan

DO NOT put plain K16's or K24's in there guys the hybrids cost a little more and give you alot of power. Please please please just call around and get pricing, some of these guys will charge you an arm and a leg for this stuff

pstoppani

+1 for hybrids
+1 for Kevin at Ultimate

Andrew 996TTS

Ok, you are going to cringe when you read this but in the end I managed to pick up a set of rebuilt K16's from a reputable supplier for a really low price and am going to put those back on the car when the engine rebuild is complete, initially.

However, having discovered the search button and reading up on the modified turbos I think it is definitely the way to go in six months when I have my new engine run in and all the bugs sorted (the car was purchased as a non runner so I am expecting plenty of problems). I would want to keep a set of stock K16's to put back on the car if I ever wanted to sell it anyway so didn't see it as a waste from that perspective.

My indy is pretty firm that if I want to go down the modified turbo path that the car should have a live remap & dyno runs done at the same time as the upgrade by a specialist to make sure it is running as it should. One of the posts above mentioned to make sure you get a kit but to be honest I am currently planning on getting the car sorted first then purchase a set of K16/26 hybrids, RUF auxillary oil cooler, upgraded ECU (I suspect mine has the early hard to modify one), Exhaust (and maybe Cat?) bypass and then take it all to an expert for remapping/dyno testing. Surely if the car is mapped live then it should be the perfect set up for the actual car ? or am I going about this the wrong way ?

I dont want to touch the internals of the engine at all, or go down the path of LWF/clutch (a new stock sachs clutch is being fitted with the engine rebuild).

Spartan, I know exactly what you mean on pricing the discrepancies are huge.

Spartan

Skip K16/26's, the hotside will be limiting factor. If you going the K16 route go K16/16g or plain jane k16/24's trust me. If you want a bigger compressor wheel than a 24 you'll need to accomidate with a larger hotside to get any real benefit imo.

The only guy I know that does custom dyno tuning on ME5 (what 993tt's have for bosch engine management) if Protomotive. I'm trying to get EPL to do it but they need a donor car for month to get the base maps setup

dbf73

what is the difference between the K16/16g's and the k16/24's? It seems to me the former is more trendy but I've missed why one would choose one or the other

Acropora

I used to have Kevin's turbos/programming but switched to Protomotive. Wanted more power.
Definitely give Todd a call before making a decision http://protomotive.com/home.html Good luck!

Barney1

I did a set of K16/16g from Bloch Turbo... Very happy with the responce and pull at top RPM. Also depending where you live, see if you can ditch the cats. Gobbs more power with the correct tune. I had Mihn at Autothority do my computer with great success, and safe. I run 17.5 psi on 93 octane fuel. Love my set up.