Restictors
Turbo Mini Forums

Hi All,
Does anyone know what type of restictor to put into a garret t3 turbo to gain more torque?
Cheers all

I'm not sure what you are getting at buddy. The only application of restrictors to turbos I know is in rallying where they all have to use a restrictor which is a hole of a set diameter, to basically limit power.

FYI
http://www.rallycars.com/Cars/turbo_restrictors.html

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

to follow on from what Tom's saying, I believe the rally cars use the restrictor, to limit bhp whilst still producing monsterous torque figures. they can make huge torque through running mental boost, but power is ultimately limited by the airflow through the restrictor, which i think is something like 34mm on the WRC cars, it's very small anyway, I seem to remember it being comparable to an SU in size!

Mr. Prawn, the friendly Crustacean- slowly making steps towards forced induction.

Right, so by inserting a restrictor, it increases torque levels (like i thought) But increases turbo lag. So is it possible Anti-Lag can be fitted to a mini without an ecu?
Cheers

Click the search button just to the left of the log out button and have a search for Anti-lag (tick the search post body for more results). This topic has been covered a few times.

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

no.

on rally cars the effectivly cap the top end power by using a restrictor, the then spend a massive amount of development shifting all the power to the bottom end to get around the restrictor as much as possible,

The rally cars use the restrictor because it is in their rules, and they have to. If they did not have to have it, they would not.

If you seriously believe this to be true then bolt a plate onto the inlet of the compressor and drill a 5mm hole in it. Hey presto 300lb/ft.

Seriously though you are lacking some basic internal combustion knowledge. This is no bad thing as we all were at one point and non of us know it all. Go and find a book about engines and then you will understand why this won't work and why this is a silly question.

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

Not being funny but why bother even thinking about this?? do you have a turbocharged mini, if so what torque figure do you have?

if i had much more torque with a T3 the car would be unusable on the road and a pig to keep in a straight line!

How much torque do you need?

Right people, not to put anyone down, i was asking if its possible to insert a restictor into the turbo!!!! Ben H, to clarify, i have a pretty good knowledge with cars engines etc, im undertaking a level 2 motorsport engineering course at the moment as im only 16. In the past 6 months, i have been involved in a full rebuiltd on a subaru impreza 2.0 ej20. This involved stipping down the engine and components down completly, it needed a rebore as it blew a hole right through piston number 3. So it was rebored to a 2.1 by alan jefferies, fitted withwosner pistons, it now has forged internals, closed deck block, ported and polished head, roger clark motorsport race bearings, 18g td05 turbo with a 32mm restictor in it, all gaskets replaced with comutec,replaced the top mount intercooler to a front mount, uprated fuel pump with swirl pot, 660 injectors, simtec ecu fitted with anti lag. At present its running 340 bhp with 388 pound foot of torqe. Had to restict engine to 340 bhp as gearbox, td05 turbo and maf sensor start to break down at 350 hp.

The impreza has been rebuilt for one track car for the older generation, and the mini is being rebuilt for me, brothers and cousins to use. i dont pretend i know it all but have been around engines and cars all my llife. I just wondered how far i could push a mini engine to get nice torque levels to have fun out on track, as we all know its not all about straight line speed.

Yes, but a restrictor is not the answer. If you want lower down torque, build a high compression engine with a small turbo.

As stated really, remove the restrictor from a WRC car and you could make loads more power and torque.

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

Right, just to clarify this.

The torque that an engine produces is directly realted to the engines volumetric efficiency. The more air that the engine can cram into the cylinder the more torque and hence power it will produce.

Restricting the air flow will reduce the torque, not increase it.

I can see that you have some good experience with cars and engines but, with respect, there is a difference between knowing "what" produces power and "why" it produces power.

I would hazard a guess that "restrictors" are misunderstood as to their intented application.

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."

restrictors get used in scoobys when all the cat's are removed as the standard boost controll is to slow and you get a boost spike and hit fuel cut. if you have proper boost controll (remember to use your own lines as the subaru lines have a restrictor pellet) you do not need or want the restrictor.

the restrictor is a bodge to get around boost controll issues, and to jsutify there fitment many shoddy tuners claim it will increase torque, words liek back pressure and gas velocity are often thrown in here. its a bodge.

2jz supras often have restrictors fitted for the same reason.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Right lads i no fook all about turbos and compressor maps etc.

Ive had my turbo rebuilt buy a local company near us (turbo center ) and in all his waffling i got told he would fit me a 360 thrust bearing and bigger inernal wheel, obviously the bigger blades will cause more lag so he recond to compensate this they fit a tapered restrictor to try and help. (am sure ive got a pic somwhere, give me 5).

So thinking about it its prob just bolocks and ive been had but ho well nothing i can do now.

Rick

WWW.FORCE-RACING.CO.UK PLEASE CLICK HERE

http://www.turbocentreuk.co.uk/

this place carl

looks like a standard metty compressor housing to me

nah its had a cone pressed in, im assuming the blades are wider than the opening to them?

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

They do go past the cone, so have i been fed a load of shit or is it there for a reason

Rick

ps its aparently got an extra sealing ring in the exhaust side to help plowing seals cos ive got a straight through exhaust

the only possible thing i can think of is this effectively increases the tip height of the compressor so the air has a longer sealed path to gain momentum, so should be able to sustain a given boost with less shaft speed, but this will only work if the restrictor cone thingy is a bawhair away from the compressor wheel, otherwise itll jsut act as a restrictor. either way, its strangling the turbo, wouldnt be in mine thats for sure. even if it works.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Right, I can see that fitting such a device to the compressor inlet would fool it into thinking that it was a lower trim compressor wheel. It would accelerate the air going into the compressor quicker and as the outer part of the compressor blades would be blanked off, it would behave like a smaller turbo.

The high efficiency island of the compressor map would be shifted to the left a bit. But I expect efficiency would be reduced as a result.

It may also spool up quicker due to a lower load on the turbine.

However, it's a substitute for actually getting the right turbo in the first place.

Also, technically, it is not a restrictor as it modifies the compressor performance rather than restricts air flow.

Restrictors are much smaller and attempt to limit the airflow rather than modify the compressor performance.

Mini wise, forget it.

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."

Sorry luke for jumping thread, hope its all helping tho

Paul, dennis,

In your eyes if i can remove it would you ??

Rick

i would!

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.