Who's upgraded their turbo ?

Hi Guys...

Wanted to know if you changed your turbo - what did you replace it with, and what rpm does it start to spool and what rpm full boost at PLEASE.

i am aware of some of the big hitters that spool later than the original VF ? variant, but I want the absolute lowest spool that will crack 400 and then some.

The MD321T is said to hit 1 bar at 2400 and full boost at 2700 - so says Mark at Lateral regarding Andy F's road car - haven't had this confirmed yet as Andy F doesn't reply to emails so it seems... shall have to call sometime.

If I lived out in the sticks the spool wouldnt be such a big deal, but as I live in SE London its a big deal to have late spool.

So my standard turbo spools at 3000k with full boost at 3500 'ish ( 'nice' enginetuner forged rebuild with ported and polished heads, and decat H+S d/pipe fitted to PPP system).

Ideally I would like full boost by 3000k absolute latest and max power to go with it. After running around with 365/365 (enginetuner conservative dyno figures) 400 - 420 should be enough -its just the delivery that concerns me.

Shame Subaru messed up with the Cosworth car by fitting laggy headers and a 'crappy owen developments turbo' (quote from someone else) - which created 'old skool' turbo lag and really spoilt what should have been a really superb 'road' car. On their test mule a faster spooling MD555 variant was fitted first which was deemed 'too powerful' at 420bhp ? ? ? and was junked in favour of a cheaper option... madness.

So what have you replaced your original turbo with and where does the power come in ?

Thanks

A

Check out the Litchfield twin scroll. The LM400 seems to be exceptionally good. Last few pages give details.
http://bbs.scoobynet.com/753591-litchfield-twin-scroll-turbo-19.html
I've gone for the LM480, awaiting final map after running in. Will post details.

Stan we spoke before, and I've seen your car more than a couple of times down at Alans. I hope it all works out when mapped - and that you get exactly what it says on the tin : )
The LM400 I thought was aimed at 2.0l cars and not the 2.5 ? Plus I haven't seen anyone verify actual spool times - great power but when ? I look forward to someone giving me some actual specs as experienced.
Also am waiting with baited breath to see how "JaySti" from SN gets on with a similar spec to you but with the SC50 billet turbo (which I actually saw last time in Plmyton).
So I really hope your car breaks all the records and exceeds every expectation as you've waited SUCH a long time mate.

Best

A

Doh ! Forgotten we'd chatted before - I blame the alcohol and age
So it may be a twinscroll 450 would leave plenty of reserve to do 420-440.
I'd chat to Iain Litcho as he is most knowledgeable about these engines/turbos.

Hopefully Martyn will do a "final" map this week so I'll be able to report results.
I'm hoping for 460-70 at hopefully < 1.7bar.

Maybe Stan... all depends how they spool / boost.

The MD321T isn't the newest turbo on the block but it is well proven and does deliver the goods. Add to that that 'seemingly' it can be made to be an 'early riser' - very tempting. Second hand they go for £800 and that's not too bad compared to the cost of a new twin-scroll and new headers/up-pipe combo etc. etc. I understand the Litchfield 'kit' is around £3k... BUT what can it do that the MD321T can't.

Hence my posting and questions.

I am more than willing to sacrifice 30/40 bhp for a car that drives really well all through the rev range.

TBH I am a little surprised that not many peeps have changed turbos this side of the pond... probably because not many have been sold... and then not many have lasted too ;-

A

I have an MD321T going on mine very shortly............

Through my wife's RB5 running first an MD321T (before running an MD321V) I have real world experience of what this turbo is like.

First off, for a turbo that will do 465+ easily it has very good road manners. Not too much lag and great boost hold till redline. This is a proven turbo (unlike the twin-scroll turbos mentioned in this thread) and extremely strong - it was ran with a DV without issue. On the road I doubt you'd see any difference between the twin-scroll and the 'T - just because it's been around a bit doesn't mean it still can't do the business (and you're not tied to a particular up/down-pipe combo).

Here's a graph of the RB5 on a race fuel map (power - fly and torque at wheels fyi) -



(However, if you can afford it go for the 321V - now that IS a turbo and a half....)

Phil I like what I'm hearing there. Experience is priceless. And the MD321T is 'well proven'.

On the RB5 - was it a 2.5 conversion then ? And when did it begin to spool - and when was full boost ?

On the hatch, how it compares to the standard turbo will be very interesting.

We wait with baited breath.

Thanks for that.

A

Yes, it was a 2.5 conversion - going on memory 1.0 bar @ 2.8k and full boost (2.1bar in this case) at approx 3.5k. It didn't have a vicious powerband though as was mapped to be progressive (most people who went out in the car couldn't believe how well mannered it was).

My hatch is currently undergoing it's build at the moment (using same components as the RB5 build) - reckoning on 470/470 which will make it a very quick, useable road car indeed (given that the chassis is fantastic).

Hi Phil
Been told that the MD 321T is not a straight fit on the hatch as its not kinked... meaning modding something for it to fit properly. let us all know how it all works out.

A