I have a superspool turbo to go onto my 20vt and my mate has a 20vt with a gtir hybrid already fitted...

Anyone know the main difference between these two in spec and how they perform?

Are they both equal but have different power deliveries as my mates is 301 bhp and the coupe I got the superspool off was 302 bhp at the same boost levels.

So what is the difference between these two t28 hybrid turbos and is one better than the other?

Gtir is alot better than a superspool.. Don't know how you got 300bhp as I could only get 280bhp on a superspool and 290bhp on a gtir. I will put some specs up later for you.

A superspool is about half way in between the standard one and GTiR in terms of size, power, and spool up, but it should have a 360 thrust bearing and uprated oil seals just like the GTiR.

It was jimos old coupe I got the turbo off, the printouts were for 302bhp @1.2 bar and apparantly 307 fl/lbs now either its a very optimistic rolling road or something but the car did feel as quick as my mates gtir turbo'd coupe. So if the superspool is only halfway between the std and a gtir turbo there must be some spec differences then I take it?

Yes..the size of the comp wheel. Its bigger than the standard one but smaller than the gtir's

A GTiR'c coop will be faster and feel faster than the same coop with the same mods. Different cars make different power with the same mods though.

I think JimO had a big downpipe and exhaust that would have allowed it to flow a bit more. The dyno could of course been a bit optimistic also

No way would it produce 302bhp at 1.2 bar !

I have a superspool and C&B cams, it was mapped by Tweenierob RIP at 1.4 bar and produced 300bhp.

The GtiR and superspool have different turbines and similar compressors, the superspool has quite a harsh delivery of torque at 2500rpm where the GtiR is a little more gentle but with a slightly better top end.

It was a powerful car, it made 272 on a std turbo, plus extras, with a PT unichip remap.

With the SS turbo it was remapped at PT with a gtech 2 and got 302 / 307 as BMCU states.

At that time though, it had an evo IC, new boost controller, new rad, new injectors, 3" decat and was running very well.

But as Jimbo says the SS was very harsh in its delivery, it was either off or scrabbling under boost, it wasn't very smooth!

They have the same compressor wheel? Always thought it was bigger on the gtir

gtir 60 trim comp.

Superspool 55 trim.

Standard is 50 trim.

Ah so it is bigger. Thanks for clearing that up

Are there variation in sizes for the turbine side Rog?

Who's been touching my post up?

That is entirely subjective and depends if you want quick spool and less top end, or the other way round.

10bhp peak power is neither here nor there, and certainly does not tell you which car would be quicker - that could just be a day to day variance even on the same rollin road, and does not take into account the power / torque curve of the car.

On standard cams, head etc. I would expect a car running a superspool to make about 280 bhp at 1.2 or 1.3 bar of boost when running a three inch downpipe and decent FMIC. On the same spec car a gtir would make 10-15 bhp more at the top end.

the turbine wheels are all the same, except my stage 2 hybrid which is the biggest available.

Rog, doesn't the superspool have a smaller or possibly cut back turbine to enable it to spool up a larger than standard compressor faster than a standard turbo ?

You'll have to forgive my lack of turbo innards knowlege ?

nope, none of them have cut back blades, that was an option on the old Essex turbo group buy years ago for the compressor wheel and is not really recommended to be honest, makes sod all difference.

I believe the TD version of the Gti-R hybrid does Rog. Or I'm sure mine did - although that was purchased more than 4 years ago.

definately doesnt. Have one sitting here, its my demo turbo to show how they wear. Its a TD turbo from kevins old coupe, supplied by barbs.

Well it won't be just a case of strapping the turbo to it, iv got jimo's full spec basically. His downpipe and exhaust, his greddy, his evo fmic even his induction kit so shouldn't be too bad. I have a gtec2 ready for flea to map over it on the 31st. I'm not bothered if I don't make 300 bhp I'm only after 280 anyway if I get 290 bonus but I'm not bothered aslong as its over 275 I will be peased.

would you get up to 280bhp on a 55trim compressor wheel and would cutback turbine blades not cause the turbo to spool up slower but allow more at the top end

any chance of those specs mate cheers

Not sure of superspool's specs but the GTiR is:

Inducer: 46.5mm
Exducer: 60mm
Trim: 60

options include

1.Ported wastegate
2.Uprated large poppet valve
3.Cut back turbine blades
4.Uprated actuators
5.Uprated actuator brackets
6.Modified compressor inlet duct.

Roller bearing turbo can be mad with similar specs


GT28R/RS/RSR probably cheaper though unless you are rebuilding an old turbo.

oh and super spool is

Superspool had a far better torque than Gtir. it gave a better more usable torque range.

Gtir is good for top end though it has a lethargic response compared to Superspool.

All this is still relative to the additional mods in the car.

Seems that TD do give a cut back turbine wheel, maybe it was optional as ive not seen one over the years.

Thank god for that, I thought I was going mad

I remember talking to one of the guys at TD and he said something about cutting the turbine blades to reduce spool up.

Mine was the first superspool though Rog, they may have changed the design now ?

would have thought cutting back the turbine blades would increase lag as it allows more air to flow though by reducing surface area

yes but less blades = lighter wheel.

the curvature and amount of blade trimming of the blades is where it can be screwed up.

this is where you gotta know what you're doing.

Not sure, maybe less mass on the turbine will give you a faster spool, I guess it depends on exactly what they are cutting back ?


Which is what Rog just said

so in theory you could trim the wheel and it would spool up just the same as an untrimmed wheel and still have the bonus of flowing more air at the top end