After asking around, both on here and at the AGM about what route to take with regards to replacing the standard turbo without going silly, I spoke to 2 companies today, CR Turbos and The Turbo Centre in Wakefield.

After seeing a few cars in action, and a ride in T's I came away a little bit envious to say the least. So, my Turbo is almost off, but I have run out of light. I havent received what I was told via an email yet but it looks like I will be receiving GT28 something or other internals I am not sure about the technical side of things, I dont really understand it all if I am honest, but there could be a bit of machining of the housing?? involved, a 360 bearing, uprated seals - I think this might mean I can decat in the near future but not sure?? - and a larger/more trims turbine???

Basically, I hate you lot!!! Sorry, thats a bit harsh, my wallet hates you lot!!!

Any opinions welcomed, and if you understand what I might have been told and can explain in simple terms, please feel free... I will post the emails as and when I receive them for further info.

A remap will be on the shopping list soon after fitment too.

I am a salesmans dream!

I should have taken you out and no doubt you would have ordered a GT30xx turbo

I think if you had done that, then I would have probably nicked your car to go home in while you were scoffing your breakfast on Sunday morning!

A refurb will be your standard turbo with uprated seals and a 360 degree bearing. This will mean you can run a decat, something the factory turbos can't do very well as the seals blow.

You have 2 turbines (fans) in a turbo. One is in the exhaust (hot side) and the other in the air intake (cold side). As you drive from low revs the exhaust gasses cause the hot side to spin, which in turn causes the cold side to spin. If you increase the size of the cold side turbine you will be able to create more boost pressure higher up the rev range. As the engine rpms increase so do the turbos and the standard smaller turbine cannot maintain the a higher boost pressure above 5k rpm, where as a larger turbine will. Hence more power at the top end.

Anything with the phrase hybrid will increase the size of one or both of the turbines. A Stage 1 CR Turbo will increase the size of the inlet turbine and hence your car will be able to have more power at the top end. A stage 2 CR turbo will increase both the hot and cold side, but ideally you'd need other supporting mods with this turbo eg FMIC.

Hi, Gunzi. Turbos actually have one turbine and one compressor. The turbine (aka. wheel/shaft) is the one driven by the exhaust, the compressor (often abbreviated to comp) is the one that compresses the intake air.

Quick explaination of seals, thrust bearings etc:

oil seal
the oil seal fits around around the turbine shaft and prevents oil inside the turbo escaping down the shaft and into the exhaust. an 'uprated' oil seal will usually mean a staggered-gap seal which makes it harder for oil to escape down the shaft.

Bearings
The turbine shaft spins inside two cylindrical bearings. This come in of two flavours (and in some turbos one of each);

>journal bearings- channel a oil round them so the shaft actually sits on a thin film of pressurised oil. These are the type of bearing most commonly used in turbos. They're reliable, cheap and easy to refurb.
Note: Ball bearing turbos don't have thrust bearings as the ball bearings take the thrust loads as well

>ball bearings- exactly like the bearings you see inside a wheel. Oil creates drag on the spinning turbine shaft. Ball bearings only need a very small amount of oil just to lubricate them - hence why ball bearing turbos spin up more quickly than comparable journal bearing ones. They can also withstand higher loads Downside is they're much more expensive and you can't rebuild the centre housings - making them even more expensive.


thrust bearing
Imagine picking up a turbo. Grab the comp wheel and try to pull it in and out. What you're doing is inducing a thrust load upon the thrust bearing. In use the bearing channels oil around it so the back of the compressor (well, the thrust collar) sits on a cushion of oil. a stock 270 degree thrust bearing looks like a dougnut with a bite taken out of it, so it only provides 270 degrees of oil cushion.

A 360 degree thrust bearing, on the other hand, is a full doughnt! Therefore it can provide much greater protection against high thrust loads. If you consistantly run over 15 psi then your turbo needs one for long-term durability.

Note: ball bearing turbos don't have thrust bearings because the ball bearing also take the thrust loads.

a/r and trim:
Read here for a good description of area/radius ratio and compressor and turbine trims:
http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_tech102.html

If you want to see what the insides of a turbo, 270 and 360 degree thrust bearings, and stock/uprated oil seals: I have photos of them in the last post of my project thread:
http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=794652

Also ball bearing turbo need water cooling, as the pressurised oil on a 'normal' turbo actually takes care of cooling, and there isn't much oil present in a ball bearing turbo.

There's also a variant of a ball bearing turbo made by an Australian company with silicon nitride ball bearings. I haven't seen them being used on here, but they do several Garrett conversions.

Ok, quick search found them.

http://www.mrturbo.com/catalog/120_turbo/turbo.html

Wow I rarely venture into the tuning and projects areas. If I'd known your posts were so entertaining and informative I'd have taken a look you make tuning sound like fun rather than fear Great job on the car too

<note to self> keep out of the tuning section........ keep out of the tuning section ............ keep out of the tuning section ........ </note to self off>

Agreed, in this instance I was going for a simplistic explanation, I guess I should have used the correct terminology

Thanks for the info guys. Some of it is still a bit over my head, but I will get there eventually.

The turbo is all but off, I forgot to take a 13mm bolt from the bracket which bolts to the engine. Its stuck fast but the bracket is preventing me from dropping the turbo out of the bottom . Fresh arms and eyes needed for what will hopefully be a quick job tomorrow night so I can get it sent off on Friday and built back up next week.

Cheers, Came2dance. That's a large part of why I post up on the Project page. To show people that modifying/repairing your Coupe is nothing to be scared of! And hopefully to help people with their own projects, or spur them into starting their own. Nothing beats the feeling of building your own. Whether it's building an engine - or just bolting the turbo on!