T2 Boost
Turbo Mini Forums

Ok...

So ive checked the search facility and couldnt find anything, so i thought that i'd post here..

Ive bought a T2 in an unknown condition so i intend to rebuild it anyway but my question is, what amount of boost can a T2 reliably handle assuming that everything else is in order? CR will be around 7:1

Im hoping for around a tractable 150 banana engine which a nice torque curve, 276 cam, intercooler, modded head etc and possibly a megajolt.

Additionally, what pistons do people recommend on here and which suppliers are both cheap and decent? I dont mind buying internationally if it gets me a cheap deal.

Cheers,

Mike

It depends which T2.

I'm sure that I read on TurboPhil's site that 16psi was the most that could be extracted from his T2 from a R5 GTT.

In the 13's at last!.. Just

7:1 is a bit low, especially if you want tractability, I'd aim towards 8 - 8.5.

I'm sure I will be corrected if wrong but 7:1 is a very low CR for your application

And personally for 150bhp I would say megajolt is essential not optional.

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

I think that you will need to upgrade the turbo thrust bearing for anymore than 15psi boost. Besides, you should be able to get 150hp at the flywheel from less than 15psi.

Pistons are best from Minisport - Australia - do a search for "Hypatec"

Aim for 8.5:1 CR if you are planning on a good intercooler.

The 276 cam is too radical - use a 266/255 or SW5.

Edited by Paul S on 26th Jan, 2009.

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."

The T2 will run 15psi, but compared to modern turbos, it's not very efficient at these levels of boost. 12psi is a nicer zone to be in.

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

I am curious why everybody runs such low CR.
I am running around 9.6:1 and 1bar and I think this is low.

Response if really good (will be putting a 266 in shortly to improve low end torque).
I do however use 98 Super unleaded + Millers (which includes a mild octane booster) and a charge cooler that sees around 20deg max above ambient

My ignition is mapped at around 10-11deg retard for 1bar.

Thanks for the kind advice.

if a 266 / 255 cam is all thats needed, would an MG Metro cam be suitable instead?

The reason for me asking, is that im about to source an MG Metro engine that i was considering turbo charging.

Mike

MG Metro cam makes and excellent turbo cam. As long as it is good condition.

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

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

I would have thought dropping the boost and running more advance would be a better option.as well, it's always a compromise!

I run 11degrees retard from base N/A map so around 21deg advance at 1bar.

Current cam may mitigate knock slightly but I doubt it. My cam closes the inlet too late but not excessively so.

On my logger I see just over 100kW (calculated at the wheels)
not sure how accurate this is but relatively sensible compared to my old N/A setup of just over 60kW

Hi,

Ive emailed Minisport Australia and they only guarantee pistons up to 7.5 psi and they have a 7cc dish.

Is there a specific model of piston you recommend Paul S ?


Mike

were running up to 30 psi on a t25 in a discovery .theres a noticable power increase going from 25 to 30 psi .big ic.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

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."