Projekt Alpinweiss IV part I - 350PS

[Rusty]

I know that I'm happy with the little Alpinweiss at the moment, it was like a rocket last night in 3degC air and a little dampness. Part of my happiness comes from the fact that the next proper step up in power is about 400bhp and for this I'll need about £6k to do the job properly as, for peace of mind, I'll need a complete bottom end rebuild and an uprated clutch along with the other gubbins, all of which costs a small fortune, even if a k26/7 or CT350 really is good VFM at the IMO. I think for this level of power I'd also be looking at a reverse inlet and a few other toys, all of which start to add up £ wise and that's not possible at the moment

Soooooo, to the projekt in hand, the aim is to retain the stock bottom end and clutch (<5k on my 3B item) and using a small hybrid, utilise what I have (3" DP, RS2 IC, modified inlet etc.) to good effect. Aims are based on ericd (340bhp), T2Andy (330bhp) and a few others running 'small hybrids' from MTM and Nothelle.

Basically the aim is to get 10-15% more power with no increase in lag and similar torque characteristics to the K24 7000, all on a strict budget of around £1k. I think this rules out a CT turbo although I'd be interested to know what teeny tiny CTs are available for modest power ouputs. I would consider a larger turbo but prefer the idea of using what I have to best effect rather than strapping on a monster and running it at 75%. That projekt can wait till later :mischeif:

My first question relates to the stock bottom end, will a small hybrid running a 2.2 bar WG spring mince the bottom end as the RS2 item has been shown to do? I'd happily leave the 2.5 bar MAP sensor in there for a more cost effective solution. I want sharp spool up, none of the stock car's hesitation as the boost is rather slovenly controlled by the N75.

I see a basic list of parts as this (as lots of other work has already been done ):-

• Small hybrid (spec to be discussed here) - bolt on, £500
• RS2 EM £150-£200 for a crack free one
• RS2 injectors, £150
• 3 bar MAP sensor + ECU remap (perhaps Paul N is intrerested here :mischeif £?
• Odds and sods £100

Other nicities (wishlist ) are:-
A)

• Flowed and checked head
• Reverse inlet using the RS2 IC with some simple mods

B)

• Wagner RS2 Evo EM
• Wagner RS2 Evo IC

C)

• Wagner Reverse Inlet kit (EM, IM, XC, IC)

As ever, more for fun than anything else but who knows what I'll do :mischeif:

[Jamo]

Nice project, don't know about the budget there as remap and map sensor is arund £650 at MRC, You'd have to look at Automark who are cheaper and maybe S2central but then travel is an issue.

[Rusty]

Cheers Jamo, to start with I'm interested in what turbos suit my requirements (other than a restrained RS2 item or larger, as mentioned above). I know Andy has recently has a recon AET unit fitted to his MTM (after the RR results thread) and also remember ericd getting some nice numbers at the Weston RR day, there's also the bad influence that is Mr. Simmonds, whose car seems to be the 3B doppelganger of mine more and more (or vice versa)

I think that realistically I want to use secondhand RS2 parts where applicable as that should keep costs lower and they are well understood and proven parts on these cars, thus making me think of them as reliable...

Forgot one other wish list item:- Water Injection, not to have it mapped with but just to provide some additional performance in the summer when track days, 1/4 mile sprints and possibly some hillclimbing migh occur (big tank can go behind the passenger seat or in the 'boot').

[sjw185]

Good Project

Looking forward to seeing the results of my hybrid after getting my 3"downpipe on and injectors sorted as I was getting 330hp with a gammy injector and standard exhaust

[K Simmonds]

Sounds like a good plan Andy. I've just got my revised/rebuilt turbo back from AET, I dealt with a chap called Andy as it happens. Have to say he was very helpful, asked what sort of power delivery and outright BHP/torque I'm after and we spent quite a long time on the phone going through my options even using Garret hybrids ect. I know it's in their interest to be helpful but this guy knows his stuff and certainly doesn't try and feed you any nonsense.

I'm after much the same sort of goals as you, 350+ BHP with minimal lag on a stock bottom end. My previous hybrid was apparently good for about 320/330 top's, the limiting factor being the size of the compressor wheel. My old turbine housing was cracked so I've basically got a whole new unit with a 360 bearing, the only parts from my original turbo that have been retained are the compressor housing and the exhaust turbine and shaft.

The spec now is.

Cold side now uses a genuine RS2 compressor wheel and back plate, my old compressor housing has been machined out to suit the RS2 wheel.

Brand new centre section with 360 bearing.

Brand new K24 turbine housing machined out to match my original Nothelle small K26 turbine wheel which I retained on Andy's advice. Apparently it's only very slightly smaller than the RS2 turbine wheel and is quite capable of driving the now larger compressor.

I told him I planned to get the car mapped by MRC, Andy reckoned it should now be capable of running 2.0 bar (just) with very fast spool up giving limited lag. Though I won't be pushing it right to its limits as I want a nice safe set up, will probably be mapped to no more than 1.8/9 bar. He did say I'd have to be careful of it's low down torque capability with my stock bottom end, hence me deciding to look to MRC.

Anyway it cost about £600 for the completely revised unit, which was more than I was planning to spend but there we go.

[Rusty]

Yeah, I really want to run a big WG spring for more part throttle driveability and have to avoid a turbo that will mince the bottom end, if that limits me to 330bhp then that's fine, it's within my 10% gain bracket and will have the added bonus of a lower boost threshold. I'm hoping to play big WG springs on the k24 7000 and will know from this if that's the way that I want to go. If I wanted to use the N75 for initial boost then I'd go RS2 or CT350 and have it all future-proofed but that's not the plan (in my head, at the moment ) :mischeif:

[dest]

Im certain I posted a thread similar to this a while ago, basically wondering if there was a setup that would sit between the homefry and RS2 power levels without having to spend a fortune on changing rods, bigger I/C and so forth.
Does the Nothelle set up use a different inlet manifold or is it pretty much just a hybrid turbo and remap?
Something along the lines of that would be perfect; ie change the turbo, bigger injectors, exhaust system and remap.

Side note: would the standard downpipe be any good for 330bhp or so, if you already had a cat back Milltek for example?
How about the intake manifold? Can the standard one take 330bhp?
Have I read right that the standard turbo is only good for 300bhp? So if that was replaced but everything else kept standard, how well would that work?

[Rusty]

Intake can do 500bhp, it's the exhaust manifold that needs to be changed out for RS2.

Stock DP is early 300s, RS2 is late 300s.

Ideally I'd like something that can run 1.5 bar all the way through to the redline, that should give the sort of power that I'm looking for on a smaller turbo, RS2 high boost run 1.7bar redline I believe, 1.9 in the midrange and are OK for stock bottom end. I'm happy enough with the 330ftlbs that I have but would like it to pull more past 6k5. The mods that I've already done have made the car rev a lot better, unlike a stock ABY that dies at 6k, mine will last into the lat 6s before it feels flat, obviously different to a big turbo but that's not the point here.

[Kieron20V]

Im certain I posted a thread similar to this a while ago, basically wondering if there was a setup that would sit between the homefry and RS2 power levels without having to spend a fortune on changing rods, bigger I/C and so forth.
Does the Nothelle set up use a different inlet manifold or is it pretty much just a hybrid turbo and remap?
Something along the lines of that would be perfect; ie change the turbo, bigger injectors, exhaust system and remap.

Side note: would the standard downpipe be any good for 330bhp or so, if you already had a cat back Milltek for example?
How about the intake manifold? Can the standard one take 330bhp?
Have I read right that the standard turbo is only good for 300bhp? So if that was replaced but everything else kept standard, how well would that work?

Dest, I have ericd's old car, Nothelle conversion which pulled 340hp on the weston dyno as Andy said. Nothelle setup comprises a modified ABY exhaust manifold (modified runners) hybrid turbo, and ECU remap. Meaning it runs standard ABY injectors, intercooler and inlet manifold. The head is also worked over, port and polish job. I dont have a boost gauge, but it pulls from 2k on and feels like it hits max boost around 3k, pulls like a train through the midrange and starts to choke past 6.5k.

Its a great setup but I cant help but think that the injectors and intercooler are being pushed at this level. I wonder if they upped the fuel pressure to help the injectors flow a little? If I had a working battery for my laptop I would like to log the intake temps to see how the intercooler copes on long pulls.

Kieron.

[Rusty]

Get an inverter for the laptop

With RS2 parts that Nothelle turbo should do well, as would the MTM small hybrid, anything larger and it's going to get close on a larger WG spring, as Kit says above.

[dest]

Probably getting off topic to your original thread now but is there an off the shelf turbo similar to the Nothelle one?

[Rusty]

Not off topic at all Martyn, that's pretty much what I'm after. Might ask Repo what CT turbos fit the bill, I'm sure they make something for the 1.8T sized engines that would suit.

[K Simmonds]

The only turbo your going to get off the shelf that's similar to the Nothelle/MTM small K26 hybrid is a genuine RS2 K24 7200, a Garret GT28 or a small CT unit. There maybe others but those are the options I discussed with AET.

As Kieron20V rightly says the Nothelle conversion (engine wise) consists of a modified exhaust manifold (done away with this on my car due to cracks, replaced with RS2 EM). A small K26 hybrid, basic head work, full bottom end rebuild/crank assembly balanced finished off with an ECU mapped to suit. Fuel pressure remains stock AFAIK.

My Nothelle conversion is a funny one as they never officially did 3B's, the work was carried out by BRM in 1993 at massive cost. However I have all the paper work to back it up as well as the manifold I removed that's undoubtedly a Nothelle modified one. The turbo was such an obscure hybrid even AET couldn't identify the source of all the components. On close inspection the head has obviously been gas flowed and the 3B accordion hose has been done away with as well.

That said, my old turbo pre-dated the official N300 conversion, according to Andy at AET the turbine side is near identical to an RS2 item being a small K26, however the cold side on my old unit was slightly inferior compared to the one used on latter conversions and indeed the RS2. Hence me splashing out the extra to upgrade in order to get the sort of power I'm after as safely as possible.

Andy, if I were you I'd give AET a call and discuss what they can do for you. At the end of the day I sent my old turbo off for a basic rebuild (quoted about £350 with 360 bearing) but ended up with virtually a whole new unit capable of a load more with a years guarantee to boot, all be it at near twice the original cost. Have to say as well their service is excellent and the old compressor wheel and back plate are going to be put to use revising the K24 on my 10VT motor. Which by the way is the reason I've not been getting on with the S2, I've spent my last couple of weekends cleaning/inspecting my 90Q, had to, new toy and all Expect a major update to my 3B thread soon

[Rusty]

Cheers for that Kit, just doing the thinking stage now and that's useful information for sure. Shame that I fitted a stock clutch when I did the 3B flywheel conversion... funds and availability were but a few of the issues then, car had over £1k in service parts and labour in that week alone. Uprated clutch would save me a bit of a £600-800 sized headache in parts and labour.

[K Simmonds]

No worries mate.

As it happens I'm really concerned about my clutch, according to the paper work from BRM it's supposed to have an uprated Saches item but it's done 90 odd K since the conversion. Should be fine till I get my remap then I guess I'll just drive it till it breaks.