t0mt0m

love you car

paul_858

Any intercooler setup with a good efficiency ratio can improve overall performance on even the stock programming. We were able to see a significant increase on the dyno when comparing the stock SMIC vs the DUH prototype FMIC on my B5 A4. With the proper piping design, and core selection you should be able to maintain the stock pressure drop and maintain the throttle response you'd expect.

Faded lines are the stock SMIC, the solid lines are the Duh FMIC
<img src="http://paul.socaleuro.com/audi/gallery/dyno_run_comparisons/OEMplusFMICrun2small.jpg">

paul_858

<img src="http://paul.socaleuro.com/audi/gallery/dyno_run_comparisons/AMS45plusFMICrun3small.jpg">

paul_858

Only under extremely high temps + wot would you see any chance of coolant temps increasing. Oil temps are likely to climb too high as well.

AggregatVier

But looking at what Audi has done with other turbo car's wheel wells speaks volumes about other solutions. They don't use holes they use louvers than are slanted downwards. The wheels then produce a rotational airflow which more effectively scavenges air out of the engine compartment and through the IC's. This would be much more of an effect at speed than even the FMIC and is probably why Audi went with DSIC's instead of a single FMIC (don't forget all the money they spent on that hugh wind tunnel and aerodynamic studies). Plus, I noted that the vents were in particulary locations and, at least on the RS6, started about at 60-70 degrees from the horizontal wheel line. That's pretty high. Taken all together (and with the great range of compensation in the ECU) it's probably a wash between the two. Sort of personal preference but I think (and will find out) the duals really would be the obvious choice if Audi hadn't cheaped out on the wheel liners.

Now, I do note the RS4 IC's are even bigger...

AggregatVier

It's a fancy indicator light and not an actual reading of temperature. I'd rather it tracked the temperature but it's been speculated they "fixed" it so as not to worry the average American driver.

DLSJ5

Temps are the same

DLSJ5

That's awesome, how'd you get?

DLSJ5

and this Dual setup would add to that. But with regards to the Duals being a good setup, I agree, with the right Cores and for a Bi Turbo setup like the RS6 and B5 S4 the Duals would work better then a single Turbo, not as much pressure loss. These A4 OEM IC's are so small and part plastic! Not the best to compare too.

A better designed Dual setup could be comprable or possibly better with good airflow through the wheel wheels, but not these Duals, I don't know if vents are possible with everything behind them and the wheel liner. Hopefully you can make that happen. That would help with heatsoak for sure.

AggregatVier

...AWD 170 HP engine but a bigger compressor wheel and housing. It flows more to compensate for the dual IC pressure loss and to provide more air at the same rotations for an HP boost. With virtually no increase in wheel weight (the overall rotational mass/weight is the same) and bigger tubing there's no perceivable increase in lag.

I hear you about the plastic part. Having overclocked CPU's I would never use plastic in a heat sink - and that's really what the IC's are. But this is offset by the limits I put on total HP/Torque output because of my CVT. This makes me see no heat soak even on a hot SoCal day. I don't see the constant temp changes you get when tracking but even still I could feel the difference the first week I had the DFMIC's installed (late July, 115 on the streets). Still, Audi did go with dual IC's even for the RS6 and RS4 albeit with wheel well louvers and, I think, all aluminum cores.

There are definitely some venting strategy's I can work with the wheel liners but it's going to involve cutting out old S4 louvers and riveting them into the current B6 liners. I'll also have to duct or channel in some additional flow clearances around things like the windshield washer resevoir tank.