intercooler with 3" inlet/outlet ok?

[avants2turbo]

Im looking at a new intercooler for my S2 Avant that I am doing an "RS2" spec conversion, hoping for 350-380bhp with homefry etc..

Ive got an RS2 K24 7200 Turbo, and am going to get a STR cast manifold and 3" turbo back system.

my question is;

is an intercooler core size 480x185x90 with 3" inlet/Outlet (76mm) going to be ok, or is it going to cause an unacceptable pressure drop having the outlet/inlet to large?

I am picking the intercooler up tonight, so if its no good please let me know asap...

help appreciated.

Keith

[terrybullwon]

There is a really good thread some where from a year ago disscussing presure drop.. Worth a good search

[Rusty]

S2 Bo has fitted a mahoosive IC on that setup, as has Newsh (amongst others, best look at their threads and see what the results were, I don't think there's a before and after for any of them). RS2 IC is fine and neater but I think the core size you have there is too small, Bo et al used a 600 wide IIRC, you'd better check.

[avants2turbo]

S2 Bo has fitted a mahoosive IC on that setup, as has Newsh (amongst others, best look at their threads and see what the results were, I don't think there's a before and after for any of them). RS2 IC is fine and neater but I think the core size you have there is too small, Bo et al used a 600 wide IIRC, you'd better check.

to small...?

the RS2 intercooler is 500x185x63 core size, so this isnt to far off?

[Rusty]

Sorry, I was comparing to the IC that Bo & Newsh used as they were larger. If you fiond their threads then you can check the inlet amd outlet diameters and as Terry says, there's a thread on pressure drop somewhere too.

[A80Avant]

the rs2 intercooler core is one of the best out there,so if you were to get and intercooler the same size as that one aftermarket,it would probably be of less quality than the OEM one.I would suggest that you should get one made or get the one Carsten is having as then you will be able to get more potential out of the engine rather than just getting hot air in the engine.
By the way,the pressure drop is something that can be cured to a point with a remap anyway

[Jamo]

How does a remap cure pressure drop in the intake system?

On reading up on this a fair bit ideally you want 2.5 inch intake pipes from turbo outlet to throttle body to keep air speed up.

No noticely gains using 3" pipe unless your planning to run a large throttle body in which case it may be handy.

[Rusty]

How does a remap cure pressure drop in the intake system?

I would guess that being more aggressive with the way the boost comes in means that the effect of pressure drop on lag is reduced. It does not solve the problem but I don't think Papvas was indicating that it could solve it, only reduce it... of course in steady state it wouldn't make any difference.

[A80Avant]

excactly that Andy! thanks!

By the way,i fail to see what point to get a large inlet and outlet tubing on an intercooler if you are not sure that the core is of good quality and the tanks are also aerodynamically well made.If you look of all the chinese type of intercoolers out there,they are massive,but i bet a smaller core of better quality with better tank design will top the chinese ones any day.

So by getting 3inch tubes or more doesnt really change things if the core is going to cause the pressure drop anyway...

Mine is not of the most top(and expensive) quality intercooler,but it has a nice tank modification and tubing i think is 70mm(2.5inch).It manages to keep the inlet temp at about 10C inlet temp on a hot day,and 15C on a hot day in traffic.All other times it balances at about 5C especially on a cruising speed.

[gedu]

well, if you can fit a large "china" cooler, it will be much cheaper than one with better core, better flowing end tanks. It's all about price, as always

[A80Avant]

yes,but it is as much as you can fit.i didnt like to cut my bumper or modify it externally to fit it so...went the other way

[gedu]

Yeah, well stock is not an option on UrS4/6 there just isn't any room if you don't want to cut bumber

[A80Avant]

that is why a custom solution is the best way if no room is available better off paying something extra for something replacable,rather than modifying something that may become obsolete and may want ot go back to it,but you will not be able to!

[gedu]

My solution for UrS4:



Should be able to use "stock" samco hoses, with some connecting parts

[quattro20v]

Any installation pictures gedu?

Did you modify the intake or the outlet your self or can you order it that way.