old t3 to a new t3 from turbo technics difference that is
Turbo Mini Forums

well after much discussion i changed my old original t3 with a .25 exh housing with the recon from the above which use a .36 housing as you can see the housing is a lot bigger but did give some what different result.

the new one comes in later at 3000rpm instead of 2250 , which i think is better as it makes chugging about a bit more ecomonmical on the fuel fron but does come in with a bit more of a bang.

the old turbo gave just 136 bhp at the flywheel on 15 psi which was not very good for that abount of boost

but the new gave 148 bhp at the flywheel on 15 psi but with a few mods to the head and manifold in the winter i can see this getting over that.

ive posted this as some people wanted to see the differnce, when i get round to it i will also post the power graphs as well.

here is the pic.

always looking for them bigger bunches of bannanas

nice one mate. Shame it didn't make the difference you wanted, can you get bigger!

Best 1/4 mile 13.2 seconds @116 mph
First 5 port miniturbo to make over 200 bhp on a carb?
First 5 port miniturbo to make over 200 bhp on Injection?

http://www.mattwoodsphotography.com

whats the cost?

£360 all in. with next day delivery they were supub i must admit as i went direct.

always looking for them bigger bunches of bannanas

more power for the same psi?

[smug]

That must be somthing to do with more air getting in and out of the engine

Alex - [/smug]

AlexF

I thought it would be same amount of air, but less restrictive exhaust housing leaving lower back pressure before the turbine.

Team Racing

How can the same amount of air = more power?

If the power has gone up then more fuel is being burnt! More fuel being burnt also means there is the air to burn it in

QED.

Alex

AlexF

Stick a potato up your exhaust pipe and go for a run on the 1/4 mile... 10/15 psi of boost will still be generated, but you'll be quicker in a milkfloat.

You can't properly size a turbo without taking backpressure into account - what is blatantly clear is that the 0.25 is restrictive on the exhaust.

I'm really amazed you can't figure this out...

totaly agree td, the exhaust housing appeture was tniy compared to the new .36 housing so greating less back pressure which in turn on the overlap will then flow back up the inlet track which was evident when i once removed the head and found on every single inlet around the port a heavy carbon build up.

as one would say if you are chucking it in its got to get out the esier the better with comprimising flow.

thus the difference between a rc40 exhaust and a bog standard one.

and the proof is in the pudding but it would be handy to read or measur the back pressure but god nows how you would do it.

always looking for them bigger bunches of bannanas

also you have got to take in to acoount that in a ideal world you want is say 15 psi at the top of cylinder with the piston fully down the bore, but as we take the reading in the inlet manifold here also there could be a loss of say 2 psi, eg 15 psi on the gauge and only 13 psi in the cylinder due restriction in the inlet track but would be hard to get a reading of this.

as in the vizard book says you want to make bannanas not psi.

always looking for them bigger bunches of bannanas

Dave I have figured this out...

What your saying is totally correct!

Alex

AlexF

sounds like sarcasm!

Anyways - Rich, are you happy now, or are you still thinking there is more hiding away? I note your elbow hasn't been opened up aswell?

Despite the boost coming in later, is there a difference when it does (eventually - LOL!!!) start spooling - ie at 4000 rpm or similar, when you stamp on the loud pedal does it get to full boost as quickly as before, or a little slower?

not trying to be sarcastic (bar the being smug bit... that was an attempt at humour)... sorry if it came across that way...

Alex

AlexF

Sarcasm is humour!!! LOL!

Main thing is Richard happy yet?

not to you americans

AlexF

Hey - Mouth!

English and Proud!

I may drive an F-150 but it's got an England flag on the tailgate and a 'Chorley FM' sticker in the rear window!

not exactly the same, but nonetheless back pressure related, but when I replaced the std exhaust system on my old r5gtt for a more free flowing system I lost about 4psi and had to re-adjust to bring it back to what it should have been

time to get rid of my old t3 then, still using the 0.25

16V project underway

Thought you had a hybrid???

If you do indeed still have the .25 (I think you're lying ) then it's no wonder you needed that absolutely ridiculous boost you said you were running to get a high 13-sec pass!

I have been using a .36 exhaust turbine housing....

Seems to work!

JF.

EDITED DUE TO DECIMAL POIT IN WRONG PLACE, TA MW.

Edited by giallofly on 26th Aug, 2005.

i hope the point is in the wrong place jon lol other wise your car realy does well to get off the mark like that:)

Best 1/4 mile 13.2 seconds @116 mph
First 5 port miniturbo to make over 200 bhp on a carb?
First 5 port miniturbo to make over 200 bhp on Injection?

http://www.mattwoodsphotography.com

yes very happy but as dave spotted still some work to do as i think there is still some more galloping horeses to come out of the engine or the same for less boost.

but she does come in with a bit more of a bang especially at 4k

which i a way is good as when you are just chugging about i think the car is a bit more economical as the turbo isnt coming in all the time unlike before but you do lose out in another aspect reel bottom end torque unlike before.

always looking for them bigger bunches of bannanas

What cam are you running hoggy?

Whats your ignition time like?

Mine starts to boost at 2.5k and is well on boost by 3k

And its exactly the same turbo you have!

Alex

AlexF

mini williams special cam

mine is about 2.5 to start to boost and is coming in at 3k.

but it has usefull boost at 3k thats what i ment alex

timing is 24 deg fixed

always looking for them bigger bunches of bannanas