UrS4 2.2T Avant project

[Thuppu]

Thanks But this is a quite light project if you compare to some others here on the forum. Something have been done, but the car still looks like it's on way to the scrap yard.

Got new tyres assembled on two of my alloys today. I did take wider 255/30 18 tyres. Did wonder how they gona look on only 8" wide rimms, but they turn out not so bad. Pic where compared to 235/40 18 size same brand tyres.

[Thuppu]

Trying to decide here, will I go further with this turbo or do I take a step back and go with the good oldie standard HX40 super..? For spoolup testing I fitted a mechanical turbosmart boost controller and had few dyno pulls. I loose about 500-600rpm's in the mid range(time for stroker? ). You can see that before 200kW came at about 4100rpm. Now it's about 4700rpm. Don't know how much proper mapping and timing will affect spoolup though, propably not much, 100-200rpm's?

This turbo seems a bit laggy to me now when you see the plot, but it doesn't feel so bad in real life. Good thing is also the fact it makes power up to the rev limiter, so the hot side isn't a bad restriction, at least not at this power level. If I keep this, well need to raise the rev limiter to 8k at least so you larger power band. Does anyone have a dyno plot from a 2.2 with a HX50/55? Just curious how a properly mapped monster would spoolup..?

New dyno plot:


Old dyno plot:

[prj]

This looks quite laggy. I would put back HX40 Super.
But also those boost controllers are not very good. I gained more 500 rpm spoolup on JP's car when using Motronic boost control vs the apexi he had.

[Thuppu]

Yes, it's just for testing, but ok, good to know. I still not fully understand how Motronic controls the boost? Well, Dmitri, your comment didn't exactly helped me now, if you can make it a lot(500rpm) better, then it's quite nice...

[eske]

Does anyone have a dyno plot from a 2.2 with a HX50/55? Just curious how a properly mapped monster would spoolup..?

Don't know about that "monster" but here's mine with HX52 Pro.

In the dyno it hit 2bar on 4th gear at 5250rpm and in the street something like 4400rpm.

[AndyP]

What's happening with your 'good' engine? Have you re-built it yet?

[Thuppu]

Eske, you have ported head and other goodies? But really nice turbo that 52 Pro seems to be.

Have to remember that everything is wrong with my setup atm. Dmitri mapped this last summer, it burned massive of oil and lifted the head, so everything was suspended. Dmitri dropped the timings and WG control. Later I have changed the IM and turbo and now added the boost controller, so I havn't a clue what part of the maps car is using. With this turbo it goes a little rich in the mid range and leans out(perfect 0.77 lambda) in the top end, and that with about 2bar boost...

[Thuppu]

What's happening with your 'good' engine? Have you re-built it yet?

It's still on the garage floor. Got a new block for it though.

[Thuppu]

Did some research about turbo spooling and it seems that a leaner mixture can reduce the spoolup a lot. This setup goes quite rich just in the spoolup area so maybe it's just not right to judge this yet... yea I know, quite BS explanations here...

[eske]

Eske, you have ported head and other goodies?

Yea ported head, regrinded 7A cams with diy solid tappets but nothing fancy.

Can you test where you hit 2bar on 4th gear so I can compared to my old setup with hx40.

[Thuppu]

Do you have a dyno plot of the HX40?

[eske]

http://www.audiclub.fi/audifinns/sho...5&postcount=94

Only Audiclub Finland member can see it, sorry.

I think you have seen this dyno plot. Stock head, cams and 98octane

[Thuppu]

Ok, there is no rpm info, so can't compare, but seems that there isn't much difference to the 52Pro in spoolup..? How high did you have the rpm limiter?

[eske]

With hx40 and 4th gear (street) 2bar 4400rpm-4600rpm(just checked the logs). I think I made some adjustments to the wastegate (or something) so the spoolup changed 4400-4600 . Hx40 the rev limiter was 7400rpm.

[Thuppu]

Ok, that is quite normal 40 super figures in these engines. So you saying that the 52Pro spools the same?