Be interesting to see what it makes.

I'm having a constant battle of wills with myself at the moment. I want a bigger turbo, more power, more torque. But then I start asking myself does it actually need it? It's damn quick as it is and so useable and I don't want to ruin it.

I have been having that argument with myself for the past ten years! I've had a lot of cars, a lot of engines and a lot of turbos! Bigger is not always more fun and better to drive.

Looking good. Can you do a full rear shot?

From behind?

Turbo is on and road tested, seems ok, got a few weeks for shakedown yet.
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Once it's remapped I am changing the clutch and flywheel to an organic sprung centre solution. Still looking into possibilities with the clutch and cover, the paddle and unsprung centre is somewhat hard to live with!
Sachs racing do a cover that will hold 390 lbft with an organic disc, I have already made another flywheel blank to modify.

The 20g did .5 bar by 2800, 1.0 bar by 3500 and 1.3 bar by 3600 ish.
I will check what the big 16g does boost wise. Certainly does 1.5+ at 3500, quite laggy then it all comes in at once. Not sure how it holds boost as I'm not revving it above 4k. When it's on boost still 10:1 AFR so safe as houses 😂

Dig those little welded 'cylinders' for the w/g actuator's bracket to bolt to. :thumb:

Needs must, the compressor cover had to have the old bosses milled flat and the inlet pipe turned back and shortened to make it compatable. Oh and a 2" outlet welded on.
Here's the start if the new flywheel, to be continued once I score a clutch
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Having had several imprezas at various stages 240, 280, 330, 400, 420 and 500+
I have to say 330 was the perfect amount of power. Useable and most importantly reliable.

Have to agree, big turbos are not easy to drive fast, you really have to work them hard, the torque from a small turbo is far more fun on a wet road for example when trying to slide about a bit.

Right the verdict is in;
20g= .5 by 2800
1.0 by 3500
1.3 by 3600
Big 16g = .5 by 2500
1.0 by 3000
1.3 by 3200
1.55 by 3500
Small 16g. 1.5 by 3200
So as you would expect, the big 16g is right in the middle of the two.
Full boost by 3500 is very nice, very punchy. Can't wait to get a decent tune on it now.

Interested to see the results, especially how much torque it makes.

After living with my unsprung paddle clutch for about a year now (that's how long audi box has been in) I am now looking for some refinement.
Namely an organic clutch with a sprung centre that will hold the torque. NOT EASY!
The sprung centre will get rid of the gear noise I'm getting (sounds like a mild straight cut box 800-2500 rpm due to solid centre).
The current clutch is for a FWD golf/audi A3 O2M gearbox, with duel mass flywheel, no space inside the cover for a sprung centre.
The other option is the clutch for the audi gearbox, namely a 2.7 biturbo RS4 one, but god knows if that will clear the starter.
So I asked the "specialists" at CG motorsport for a few rough dimensions, dia etc. They were absolutely no help what so ever, as is the usual story (and I've had it time and time again) if your doing it yourself and making your own bits no one else is interested! Even If if your trying to buy bits off them! Thanks!
So taking a risk I have been on eBay and scored a brand new clutch kit from euro car parts.
Reduced from £290 to £134 (presumably because they aren't shifting many).
Listed for audi 3.0 TDI, S4, RS4 I can only assume it will take the torque? If it fits!
Starter may be getting even more weight reduction lol.

Flywheel is complete, made for audi B7 RS4 clutch.
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Skills! Respect!

:notworthy . . . you tart. :D

Damn your machining skills are pretty epic to be fair!!

The machining is the easy bit, it's the research and designing that takes a bit of thought!
Still don't know if the clutch will work on my gearbox

Flywheel finished bar putting the dowels in. Ready to fit, bug waiting till after the remap now.
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Looks fantastic mate. That pilot bearing setup is interesting.

I'm happy with it, the spigot bearing is a needle roller bearing pressed into an aluminium post that's pressed into the flywheel. It's the only way I could do it and keep the bolts as short as possible/flywheel as light as possible and also give clearance on the friction disc (although the disc is pretty flat on the back).
It seems the B7 RS4 (4.2 v8) clutch is a common upgrade for the B5 RS4 guys (2.7 v6 biturbo). So it must fit inside the bellhousing?! Find out soon enough.

Brilliant read as usual boosted,
Glad to see the Audi gearbox project still going strong.

Thanks, yeah must be 7000 miles on the audi box in my car now.
I even think the forged engine is on about 5000 miles now!
Remap then a clutch/flywheel to fit at some point

The verdict is in. 352bhp and 340lbft. Peak 1.6 bar, tailing off to 1.4 up the revs.
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nice numbers mr, must drive like a proper animal now?

Yeah it's ok, wet today so was spinning up all four in first!
Hard to say, feels wee bit quicker than when it had the small 16g on. Happy with the result. Andy is a top bloke, had some good conversations with him.
Injector duty cycle is 88%

Actually 353bhp and 346ftlb
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Is that at the wheels or crankshaft? I was expecting to see into the 400's with all that custom work!