.63 or .82 A/R ??

[Justin..]

dont know which to get on a T3 exhaust side of a turbo im looking to buy, anyone know which would be better suited?

[Smudger]

i lil bit of info for ya,

The A/R ratio of the exhaust housing refers to the size and shape of the scroll that is cast into the housing. It basically determines how restrictive the housing will be, versus how quickly the turbine will spin up. A lower A/R ratio (smaller scroll area, A) results in a more restrictive housing. This restriction speeds up the exhaust gasses and increases the amount that the gasses will expand. It's the speed and expansion of the gasses that causes the turbine to spin. So with a low A/R ratio, the turbine will spin up quicker, but as engine output and rpms increase, the restriction of the housing begins to build up too much back pressure on the engine, which reduces performance. A good rule of thumb for when there is too much back pressure is when the pressure in the exhaust manifold is more the half of the pressure in the cylinder. So basically, a larger A/R ratio will improve your engine's top end, while losing some mid range power and increasing turbo lag. A smaller A/R ratio will help the bottom and mid-range, but may effect the top end.

so really depends on what you want to go for, its difficult to tell which will work best on the engine you have (is it a 1.8 or a 2.0l?) but i would have said the .63 would be the best but some of the guys currently running turbo conversions might disagree and say the larger a/r is the way to go.

[Justin..]

its a 2.0 bbpt engine. http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWN:IT&ih=002

unsre as howfar i want to take it because of gearbox reliabilty

[midge]

will be good to see this! should be in the 300's?
use a 172 box

[Justin..]

been searching for ages to get one and i need a cup one aswell because of the mechanical speedo drive? or are all 172 boxes mech drive?

[MAXIBOY]

hi mate give vince a ring at CR turbo,s too. he will give you a good price on them too.

http://www.crturbos.co.uk/

[Justin..]

cheers ill do that. any idea on what would be better? im still undecided

[MAXIBOY]

Q) How much boost will this engine run?
A) A very common question, but one that can only be answered in regard of what other parts you have fitted i.e. Turbo, intercooler and ECU? Simply these components (rods and pistons) have been used at over 3 bar of boost on other 4 cylinder 2.0L Turbo applications. We have used them in house to 385BHP, have not gone further due to traction and transmission (450BHP should not be a problem?)

nice... :D .......i,m this spec and above

[Justin..]

lol i would be nice to see that but i dont think my bank would

[Crossers]

I can't see how so much power is usable in a Willy!

Mine, i'm concluding, is too powerful; wheelspinning in 4th in the dry is just crazy! Sure its fast, but it needs toning down a touch. I have to really concentrate when putting the power down, firstly to stop me floating off the road, secondly to keep some tread on my tyres!

There's no need for a huge turbo on these cars mate, T3 i think is too much.

Paul