Lucky owners of Powerstation's Type 20 conversion, please share some expirience. How does it compare to the original character of the twinscroll? Whats turbo lag like? Did anyone upgrade the turbo described in the article?
I already have zerosports intake kit, HKS exhaust manifold + 3" Fujitsubo exhaust however the ECU is stock. On the site 400+ hp kit is offered and thats exactly what I want as my stage 1. Thinking of going forged later for 500 hp, but really want to see what standard internals can offer.

 

Contact 'gussy'. He has had the 400bhp conversion fitted to his Spec C Type-RA and is best placed to tell you what the car feels like. I'm sure I remember him saying that it was spooling around 2-300rpm later, which is nothing really.

 

That is strange, I would expect the turbo to spool up the same if not earlier isn't it the beauty of twinscroll ?

 

Not if the turbo's getting bigger.

 

But isn't only the exhaust part of the turbo changed, the intake stays the same and therefore would offer same rate of spooling, right?

 

My car (T25 so you may see this as not so relevant), has no noticeable lag at all, turbo spools at about 1600-1800 rpm, but runs out of puff at about 5,500rpm

Hope that helps

 

According to the spec the turbo is changed:

Stage 4: IHI Twin Scroll Garrett Core Hybrid Turbo,
650cc Injectors, Large Inlet Hose, EcuTek Re-Map,
Milltek Exhaust, K&N Filter
~400+bhp - £4249 + VAT

Unless we're on about two different things....

 

If the IHI turbo on powerstation site is the same as the one described in the article, than we are talking about the same things.

 

Cost to power ratio that conversion is fairly expensive. Aftermarket twin scroll turbos aren't as common as the regular ones. If you really want to change turbos then I would probably suggest swapping up pipe and switching to non twin scroll turbo. I think your existing manifold and down pipe may be okay but not sure. If you source your own bits I'm sure you could get over 400 bhp for around two to two and a half K.

 

Where is the rev limiter set Martin ?

 

I already have 650 PE injectors and Zerosports crank pulley waiting to be fitted, along with APS turbo inlet pipe and possibly turbo to tmic pipe on the way, so the only thing i need really are the turbo itself along with uprated actuator and updated ECU. Does anyone know if Powerstation do an upgrade to customer's turbo or some kind of exchange?

 

The rev limiter kick in at 8,250rpm, needless to say I've never got close to that

 

The turbo used in the Powerstation 400bhp conversion is based on the MD321 I believe.

 

Cheers Martin. Is the engine running out of puff an issue, or is the huge mid-range grunt perfect ?

 

I would say it more down to the character of the 2.5 engine. Delivers it kick lower down the rev range and with the mid-range grunt there is probably no need to go higher. Whereas the EJ20 prefers to be revved more and therefore your always going into the 7.5k rpm region.

 

No not really, the only time I've ever seen it as a disadvantage was when I went to Santa Pod, too many gear changes needed.

The low & mid range on the T25 is unbelievable, 40mph in 6th gear, foot down and its really going strong, it drives more like a V8 than a 4 pot!

The only other thing that bugs me a bit is the short ratio's, you just run out of gears to throw the at torque.

 

Shift light set at 6800rpm for me ... peak BHP

TX.

 

A little extra won't hurt. Go on, let her loose.

 

Cheers.

 

Anyone considering or had the stage 2 to 4 upgrade? I've had the stage 2 on my spec C since I bought it and love the lack of lag and responsiveness from 1500 revs. Seriously thinking about the stage 4 but don't want an additional 50bhp if I lose some of the 'driveability' of the car.

 

Yes, but you have less torque at the wheels in the next gear up ... take it to the 8000 redline like it wants you to!

 

+10000

This is exactly my feeling, I wouldn't want to loose any bit of spool there is now.

 

Iain has been testing a new turbo, which he says is 'fantastic'

 

Any more details on this turbo?

 

Only that they've been testing it on 2lt cars and the Cosworth engine, and it apparently works a treat.

Iain said I should get 400bhp on my MK1 T25 with it.

 

Spec-cie I went from the stage 2 to stage 4 and for my needs which is a quick a to b car and the odd trackday thrown in its perfect if you lose any spool up I for one havent noticed it the main gain is the midrange/top end power right up to 8000 grand the rev limit light is set at 7600.

 

Is there any benifit though apart from engine note as revs increase?

TX.

 

Better acceleration!

The point of peak power is not the optimal shift point, especially on turbo-charged cars (which tend to have flatter torque curves than NA cars). Even though the torque produced by the engine starts to drop off after the point of peak power, the effect of shifting up a gear reduces the torque by a much greater degree. So you will get greater acceleration at 7500 rpm in 2nd than you will at 4000 in 3rd

And the engine note is better.

 

I take it you will need a new exhaust too to get that?

 

No it's just a bolt on part, all you need is bigger injectors!

I looked into the GT series turbo a while back but was put of by the cost, because that did need lots of pipe work changes.

Iain is working out the costs, I PM when I know more