t28 info
Turbo Mini Forums

just wondering if anyone knows if a t28 off a pulsar will bolt to the t2 adapter plates and if it is suitable, i'm guessing probably not as its on a 2L engine but if you dont ask you dont know! also is it a hybrid or is this a common size?

Jeez, WTF is it with excessivly large turbo's?

Just because a R5GT spec T2 is (IMO) very well suited to a pretty hot turbo A-series, doesn't mean that a lot more (ie a bigger turbo) is even better.

If you stick something like a T25/T28 (!) onto an A-series, it WONT be optimal. Let me re-phrase that, if you stick any larger turbo onto an A-series, it won't neccesarilly get you to the 1/4 mile post quicker than if a stock T3 was used.

The term 'hybrid' or 'hybryd' or whatever it is spelt, means that a turbocharger has been modified using parts off a different turbocharger to modify the turbo characteristics for your modified engine. For example, running the compressor wheel off the escort RSturbo on your otherwise stock metro T3 is a 'hybrid'. In the same way, running the WHOLE turbo off an escort on your metro engine, could be argued as a full hybrid. Does fitting a different gereration of turbocharger constitute a 'hybrid' (as in a T2 / T4 swap)? I don't know. Does it really matter? Basically, who cares? If it does what it's supposed to, and does it well - THAT is what matters.

Re the T28 swap - feel free to give this a go. The T2 flange WILL be the first step into mounting a T2 to the metro manifold.

just wondered if anybody had any info on this turbo is it actually smaller than a t3? just trying to reduce the 'lag' feel but without going as small as the t2 or spending large ammounts of cash on rebuilding a t3

I'm far from a turbo expert gav, but a t28 is not automaticly smaller than a t3, there is more to it than that

Team Racing

Too true...

If you go and source a T28 with a 0.80 A/R for example, you'll probably begin to spool it up at 6K rpm, so it'll probably feel a LITTLE more 'laggy' than the metro T3 with its miniature 0.25 A/R turbine...

What I really don't understand is why peeps try and re-invent the wheel. EVERYONE who tries a T2 can't fault it, and comments things on the lines of "never going back to a T3".
It's also been proven (in what is getting on for being one of the heaviest turbo minis around) that a T2 is capable of generating a sub 14-sec 1/4 mile, with just 15/16psi.

These minis are a constant development - 6 years ago everyone was running 'clockwork ignition and T3's. Now we've got many peeps running mapped ignition and different turbochargers. In 5 years time, BB turbos will probably be the new thing and 'non T3 turbos' the norm. You need to simply look around, see what others are doing, and - dare i say it - copy them. No-one is ever able to come into the fold and be the best first time out, unless you have lots and lots of money of course!!!

if you want to be different, try the t25 (TB2555) off the rover t series engines, with a .49 housing it shouldn't take long too spool up and is identical to what r5 tuners spec as a stage 3 turbo.

Shouldn't be too far off the mark if its fitted to a 1400 renault engine and works well, although it doesn't exactly 'fit' that well with the mirage kit, because the compressor trim size is pretty big so its a big housing

if you go for it i've got the part number for the compressor housing without the integrated dump valve in which you'll need if going with the mirage kit, along with a few tweaks.

What is the trim on them Dan? I imagine it's quite large given it's just a 0.49 housing?

not sure on the turbine side, but the compressor side is a 60 trim i think, i'll take some verniers home tonight to measure the turbine side

dave,

just discovered measuring inducers and exducers is not the easiest thing in the world,

but after doing the maths the trim on the turbine side is approximately a 64 trim (give or take a bit),

do you know the approx trims of metro T3 and R5 T2 as comparison?

Not off the top of my head!

Seem to remember they're in the 40/50 region though...

just been out doing some more measuring, results as follows (these are all rough measured figures!) and are quite interesting, but thats all the turbo's i've got to measure!!

TB2555 (Rover T-series Turbo)
Turbine Trim - 64 Turbine A/R 0.49
Compressor Trim - 60 Compressor A/R 0.48

TB0235 (R5 GT Turbo)
Turbine Trim - 58 Turbine A/R 0.35
Compressor Trim - 49 Compressor A/R 0.48

TB0342 (Metro Turbo)
Turbine Trim - 69 Turbine A/R 0.25
Compressor Trim - 40 Compressor A/R 0.42

might copy these across in the bit i wrote about turbo selection etc for future reference

be nice if someone worked at garrett/honeywell then we could get the 'official' trim sizes!

Edited by dan on 3rd Jun, 2005.

Anyone know what the standard a/r ratios for the metro T3 compressor and exhaust hosings are?

tom, i've edited my post with the a/r's, well its whats written on the ones in my garage anyway!!

Metro one is wrong. Turbine A/R of the metro was 0.25 - absolute guaranteed fact.

From looking at the spec's, a 60 trim T25 will indeed work with our engines, but is basically too large for even the largest most powerfull A-Series engine out there. A huge trim on the ex turbine, along with the 0.49 is also far from optimal for spooling up.



All of which will probably result in everyone going out and buying one now.

Edited by turbodave16v on 3rd Jun, 2005.

apologies dave got the turbine & compressor A/R's mixed up on the metro T3!!

i've gone for the TB2555 based on the r5 experience, time (make that a long time - lol!) will tell if I switch back to the std T2 or not.....

Edited by dan on 3rd Jun, 2005.

ok just for info the t28 was used on the pulsar and 200sx and it will bolt up to the t2 adaptor plates however it has 0.64 A/R exhaust housing and 0.60 A/R compressor cover, dont know if this is good but it seems to big!