T2 And T3
Turbo Mini Forums

About to do a rebuild and wondering which is the best turbo to put in going have them both re done but which would be the best i have one off the metro or off R5 and i was wondering cos i would of thought that the T2 turbo would be the best cos its water cooled but it blow up on the R5 and lots of people i know saying that they weren't that good. Do they hold more power though than the metro turbo?? And theres a different set up you can have with t2 does that give you more gane? and on metro turbo i take it there will be more to bore out so maybe it doesn't?

Any advice would be good !

http://www.Zeemax.com

look at the tech section as i did an artical on the benifits of both. the T2 is good up to say 10psi but cannot cope with 15psi unless its been modified

when you say carnt cope with over 10psi, do you mean it will break or just not produce any more power?

cheers
josh

Edited by JT on 19th Jul, 2006.

My build thread..

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=542985

the first T2 i got from a R5 specialist, who said it was a good secondhand item and it was OK, and lasted 2 or 3,000 miles of up to 15psi

the second lasted the same and was from a breakers yard but had almost zero play, now has lots of play and leaks water into the oil

basicaly they can produce the boost, they just dont last.

the R5 owners normally change to a hybrid to run this boost.

read your tec spec and i get the impresion that the t2 is a lot of work if i hybrid my t3 would i have the best of both world not to much lag and it will last me and yousay that normally hybrid how long would it last the t2 hybrid 6,000 thousand miles maybe??

http://www.Zeemax.com

hybrid turbos are modified normal turbos. they normaly increase the impeller size making a bigger turbo, so a hybrid T3 would be over the top for a mini, but ideal for a 2.0L montego running more boost. a hybrid T2 would be better than a standard T2 and if specified correctly would last many years.

The standard T2 from an R5 is good for boost around 10psi but when you fit a big intercooler or run more boost it has to spin faster and is not designed to do so.

There are many different degrees of hybrid turbo, some have a different thrust plate, some have different impellers, different bearings, different casings etc.

you could also go for a T25 or the garrett GT range. there are also many other makes that would work better than the 20 year old T3

So what you been about to much say i got my car running about 180bhp why wouldn't be as good as a t2

http://www.Zeemax.com

Edited by turbodave16v on 20th Jul, 2006.

T2 is still a very good turbo, I think that people saying that they are not last for long are frightening the eventual interested guy.these turbo can last a while on well used car, just let it heating before really use it, and let it cool before to stop your car (it mean two or three miles before to arrive) that's std recommandation for any turbo but you have to practice it really when you are using higher boost.
using these recommandatyion I know many gt turbos which have done 30/40 000 km's with 1.2 bars and about 170 bhp.also change your oil every 5000 it'll help a lot.
try the T2 you'll never go back.

whats the mods to be done to a R5 T2 for running higher boost and longer life?

cheers
josh

My build thread..

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=542985

mainly the bearings are upgraded to 360° ones, but if my memory's ok , they are not longer made.
but the std turbo after a rebuild can support 15 psi for a good time, some gt turbo nutters were using 2 bars of boost,and this does need absolutely 360's or BB turbo.

Alright sounds like your a big fan of the T2s but say i had my T3 done out what would i gain out of it if i had hybrid and i was running 15psi at 180bhp got any idea compared to say standard and a t2? some one told me when you have them hybrid the turbo becomes more lagy at bottom end but faster at top end cos they bore it out and put bearings in and it spins faster at top and thats what you gain is this right? And i would of thought that keeping the oil cool with water was a bad idea cos mixing maybe thought on the t3 there would be more to bore out as well? any advice whats 1.2 bars in psi ?

http://www.Zeemax.com

a std T2 will not give you suffisant flow for 180 bhp, which needs about 19lb at 2.2 pressure ratio for an a seri this meaning you'll need about 18 psi on high flow cyl head good cam etc .also the t3 40 trim can't flow this.
Hybrids are not back cutted turbos,and no more ported they are a mix of comp and turb of different turbos, genrally matching a high flow compressor,with a "small" (all is relative) turbine for a max spooling speed, this generally is needed when the engine capacity can't spool a big turbine wheel.these turbo will give you fast spool and good efficiency , high flow at high revs. cooling the oil with water is a good thing , but depend on your usage,take care to let it cool down before to shut your engine and you'll doesn't really need it.
1.2 bar is about 18 psi
fab

I should precise that I was talking about the T2/T25 range, their is a lot of other hybrids turbos for larger capacity engine which are using ported hsg, with different wheel imp thrust BB etc.
but we are not concerend by these;
a t25 40 trim will flow15 lb (about 150 bhp),
a t25 50 trim will flow 18 lb (180 bhp)
and t25 55 trim will flow 20/21 lb (200/210 bhp).
you can match these comp wheel with a t2 or t25 turb wheel,
and then with 0.35/0.41/0.47/0.60 a/r turbine housing ( the t25 being more efficient in high revs(6500/7500), the t2 one will give very good respons (3000/6000). the turbine a/r is the turbine driver ( a small one will spool very early,the bigger will be less restrictive, but will be sluggish. it's worth to find wich comb is best suited for you (0.35 spool very early but restrict past 5000, the 0.41 will do a good job up to 6000, then a 0.47 a/r is needed and can give you big numbers , but remind the respons of your turbo will start to suffer.
generally I prefer a little hard worker than a big fat

fab ,
i think youll find that a t25 50 trim will flow 19 lb at 65 % eff , at 2.2 pr (17.6psi)... which should be good enough air flow for 195 to 200 bhp ( the garrett suggestion of 1 lb per 10 bhp i feel is a bit cautious)
i know of one bike engine that had 198 bhp on one. regards robert

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

ooops !! sorry fab just got your pm, ill try ot be more diplomatic.
regards robert.

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

you're just limit on the surge line , not good,at this point I prefer to jump to the next size. this comp on a mini have proven to sort 186 bhp... no more.
but sure you have a fountain of knowledge
fab

thanks fab ,appreciate it . did you mean choke line?im sure you did.

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

Yes erm this suddenly got my head spinning lads

http://www.Zeemax.com

simply :
if you want 180 bhp you'll need a t25 50 trim compressor, check your st 1 t2 to know which turbine side it have or send me pics .

in your view which would be the ideal t2 turbo the one off the R5T the best and i heard thats two types of set ups one with an apdator plate and a other set up i'm thinking the other set up is a make your own mainfold and just wondering if thats the case ? sounds pretty straight forward when you say it like that ! need to talk simply to me cos i'm just learning but thanks for taking the time mate

http://www.Zeemax.com

I am sorry but your question above is just gibberish........
Try doing it as a list of numbered individual questions, e.g.

1) .......
2) .......
3) .........


etc............

hey peter ,just read your bit on here ,nicely put if i may say so!

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

i think what theyre trying to say is a standard t2 off and r5gtt wont cope with 180bhp

1. Gagrat t2 the best to mod?
2. Two different set ups for running the t2 which is the easest and most effective?

Thanks

http://www.Zeemax.com