turbo sizing, how small?
Turbo Mini Forums

how small can you go on a 1275 a series on the turbo? Some diesel turbo units operate up to and beyond 20psi, and are small so spin up fast and low in the revs, do small turbos work ok on the 1275 please, ta v much!

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

a small sized turbo may well boost to 20 or even 30 psi but............ has no flow capability and dosent make BIG HP numbers.

you are better to get up to speed with MAPS (sizing) for turbo application.

in short, ..... the bigger the turbo the more flow and more HP but it spools up slower, the smaller turbo spins up quickley but does not make big horspower.
in short they will make the same boost pressure.

have a play with this,

http://www.motorgeek.com/?fullpage=true&page=flowcalc

and this

http://www.squirrelpf.com/turbocalc/

It all depends what you want. There are turbos out there that wil make full boost at 2k and make 160bhp.

But you won't find a turbo that'll make 250bhp and full boost at 2k.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

could i run a garret from an 1800 ford diesel engine? the inlet and exhayst are smaller than standard mini dimentions but only right next to the turbo, then it gets way bigger both before and after? is this the flow restriction talked about above? I only want to run between 110-115hp on sc drop gears anyway, thanks v much lads

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

Have a read of the first couple of articles on this link about turbos. I found it very helpful when trying to work out turbo sizing

http://www.motorsport-developments.co.uk/stus.html

i would use a T2

1293 Turbo mini

t2 or gt17...People get good results with these, without having to faf around too much with the likes of custom manifolds.

http://cgi.ebay.co.uk/Renault-5-GT-Turbo-R...=item4cf70159da

1293 Turbo mini

somthing from an 1800 desil could be an ok size, if you have a turbo in mind see if you can get a the model number off the plate on it, you might eable to find out what gubbings are in it and therfor hhow sutable it is.

as an example, gt1752's and gt20's are both smaller than the original metro turbo but will flow far more and are more eficient.

Thanks lads, I am an engineer of 39 years of age, I am only being tight because some big tuning companys over the years have had my f***ing eyes out, top tuning companys that lie and do a very, very shoddy job and make you pay with blood etc. That was over 20 years ago and that learning curve was way steeper than any proposed power curve on some dodgy rolling road, trust me I have been there and I know, that BETTER results can be achieved with decent dirt cheap second hand parts. And these expensive manifolds are unnecesary when you can simply make them up yourself very easily. If you can weld, read a tape/rule then the skys the limit. Thinking of making my own water injection set up instead of ungainly intercoolers. Thanks fellas, respect

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

http://www.davidicke.com/headlines/47914-o...or-civilization

p.s. check out this!

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

can somebody tell me the inlet/exhayst dimensions of a t2 for comparison? ta vvv much all

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

I'd certainly always run an intercooler, even a small one will have considerable effect, and its such a simple device it cant go wrong/run out.


have a read through this, iirc it mentions t2 impeller sizes, and certainly gt17 ones.

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=10263

As a rough estimate...

you get a 14% increase in power when running a 50% effective intercooler at 1 bar boost, with a 70% efficient compressor wheel (not to mention the benefits of a cooler intake charge with regards to det).

If the intercooler were 100% effective you'd get 34% more power, pwoah!

(with 15 degC ambient)

Edited by dan187 on 8th May, 2011.

1275 N/A Sprite, 998 T2 Turbo Mayfair
1275 EFi Turbo

water injection is better in some ways, no intercooler needed at all and no flow restriction tho there is a trade off with the water, but the high boost capabilities are worth it. saving space under a mini bonnet is priceless, and you can just clip a big ram air filter straight onto the inlet housing, no need for complecated pipework and expensive silicone hoses! Water injection is fairly simple with lateral thinking, ie pressure switches/low level warning lights.etc water is free.

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

And when it inevitably goes wrong and your engine tune relies on it say bye bye pistons.

If something is worth doing, it's worth doing half of.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

i only want to run 115 max, and john, the throttle works both ways if things fail, you dont need to floor it, getting home on the choke would work!

ABS and traction control are for people that should not have bought a car that fast!
To build a fast car from demon tweeks parts is more expensive than a Bugatti Veyron outright!!

What folks are trying to say is, that if your engine is set up to the point where it relies on the water injection to supress detonation, what happens if you're flat out & you run out of water, or the nozzle blocks etc ?
With a decent intercooler there's not a lot to go wrong.

WWW.TURBO-MINI.COM