Missing BHP - Intercooler?

[byd1380]

I have just had my car at a dyno day and wasn't impressed with the results.. Current setup:

S6 Avant
AAN 120k
RS2 EM
RS2 Injectors
Volvo 7400
3" DP and full system - No Cats
1.8T coilpacks
FMIC - 450-180x63mm core!!!
Modified airbox and panel filter
Live mapped by Paul N

The car made 311bhp and 305tq : FLYWHEEL!!!

The only thing I can see wrong is my intercooler is too small. I knew it would tight at the front so I just picked a size and went with it. Cubic capacity is similar to the standard SMIC. Could this have such an effect on power? I thought the dyno was reading down, but a guy a few cars back made 450bhp in 3000GT.

project threa here

http://www.s2forum.com/forum/showthread.php?t=56706&page=2

Car peaks at 28psi and holds 21 to redline. Holding 11.6 AFR flat out in 4th gear to redline.

Thanks in Advance

Ivan

[prj]

What was the IAT like?
If the car was heat soaked like crazy on the dyno and IAT was 60+ degrees, then that could explain it.

If not, then your problem is elsewhere. Intercooler is not going to make that much difference.
I've made 400 crank on stock IC on AAN. Granted, it got hot really fast, but enough for a dyno run.

[rynaqui]

Wouldn't RS2 turbo be better at the top end of the range?

[driftin jo]

Compression test results ?

[prj]

Wouldn't RS2 turbo be better at the top end of the range?

This turbo flows about the same as a RS2 turbo. It should make 350-360 crank.

[byd1380]

I have looged IAT on a quick blast, rising about 40c above ambient, that was when it was 6c outside. I wondering if the intercooler is too small from a flow point of view, not cooling, and actual airlofw through it is worse than a standard cooler. It is only 180mm high and is a TOYOSPORT one. I have a bought a bigger one (550x225x63mm) so will try this while running no front bumper, will log IAT's then.

Thanks

Ivan

[mcandmar]

That sounds like too big a difference to me. I can tell you a stock S2 Intercooler with a homefry will stay within 10c of ambient, only exception is when sitting stationary in traffic. I suspect a combination of that, and insufficient airflow on the dyno weren't doing you any favors.

[prj]

Or the turbo is pushed way too far and blowing hot air.

If you are getting 40C above ambient in 6C weather and that's not while idling in traffic, then you are doing something wrong.

This is of course unless you are sitting in 5th or 6th with your foot down...

[byd1380]

"then you are doing something wrong." in what way? This was 4th gear pull from low revs.

[prj]

Well, I can't tell you over the internet what is wrong with your car...

[byd1380]

Update: Fitted a new intercooler, now core size is 550x225x65mm. This made a massive difference, it's like having the car remapped again. On a few test runs it's adding 7mph in places at around 115mph, will hopefully get back to the rolling road. It feels like a 350bhp + car now. Will try and post pictures later.

Ivan

[urS6Tom]

It's strange because JP fitted a 300x450x75 core (£60 from eBay) intercooler to his urS6 and it ran 500+ bhp... not sure whether he's still got the same one fitted now he's going up to 700+?

http://www.s2forum.com/forum/showthread.php?t=43652&page=5

[byd1380]

It think it was a intercooler flow restriction, the new cooler is 50mm taller so has a few extra rows/cores in it.
The one he fitted is nearly twice the volume of my original cooler. All good now.

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