RB5SCOTT

Now i'm getting a bit power hungry i was thinking about getting a new intercooler

I don't want the hassle of a front mount, i just want a more efficient top-mount. I have been looking at the APS or a STI7 intercooler

Can someone tell me if this would be a worthwille investment and what sort of gains i would get

At the moment i have:
ppp
ported headers
full decat
APS induction kit
HKS fuel controller
288bhp with 264lb/ft

Would it be ok and straight forward to fit it to my 01 with these mods

Feel free to answer
thanks
Scott

Knowlesy

Scott, already looked into this!!! the current system is meant to be the most efficient so far! though a bigger intercooler including fiitng won't see much change out of £1000, overall it isn''t worth it.

For £600 more you could have LEDA suspension, now that's worth fitting, or ou could have 8 track days at brands & practise that flame throwing trick you do by down changing.....

LOL Knowlesy "you ever gonna stop modding?"

Cosie Convert

RB

Check my thread from a few days ago re: High Efficiency TMIC
Radtek clain 30% improvement over your models I/C for 320 squids

RB5SCOTT

Knowlesy ,ever stop.........nah mate maybe at 300bhp

The APS top mount is £520, so not too bad. I should be able to fit myself and hopefully the ECU should do the rest.

I know the standard ones are supposed to be quite efficient ,but i thought that was only the larger STI ones

Scott

[Edited by RB5SCOTT - 1/14/2002 7:28:13 PM]

[Edited by RB5SCOTT - 1/14/2002 10:17:33 PM]

RB5SCOTT

Anyone else?..................................

Cheers
Scott

rollerskate_01

Hi Scott

Well I think you have reached the limit of the standard turbo. Upgrading the intercooler will only reduce the pressure loss across the intercooler and reduce the inlet air temp. (Maybe worth 10 bhp.)

In the states various MY01 have upgraded the intercooler / turbo and achieved 275BHP at the wheels. (approx 325 / 330 at the flywheel.)

Watch the torque, general opinion seems to be that when you pass 275 lb ft the gearboxes start to fail. (Gear teeth break.)

I can slip my clutch on a full blooded launch at 5000 RPM with 267 lb ft all the way to second gear. (11k miles on the clock. Only done this once!! Warranty claim !!!! I think not.)

Better the clutch than break the gearbox !!

But at the end of these concerns, go for it I will watch with interest.

[Edited by rollerskate_01 - 1/15/2002 7:24:48 AM]

Jacko

Scott, no matter what you do under the bonnet, she will still need major work in front of the bonnet

Where you are today with your mod's, I would strongly recommend the FMIC route for big air density improvements. But if you want to stick with TMIC, then for example, In my 'very limited' experience, the STiV/VI intercoolers look v.similiar externally compared to the 99/OOMY but I have been lead to believe that the internal core is fundamentally better. I have upgraded from an 97MY UK TMIC to an STiV and I have gained 3 degrees extra advance in some zones on my Link. Bob Rawle indicated that I have possibly gained 30-50% efficiency upgrading to an STiV. On the 01MY, I don't know if you would see those improvements as the standard WRX one is pretty good already.

Only what I have learned...may be utter bo77ox! Jacko

Adam M

Is a nice idea, but since you have all these mods already, I think the best way to capitalise on it for a similar amount of money is to get bob rawle to fit you a link ecu.

It will enable you to see the benefits for yourself if you do fit an uprated intercooler later on.

Jacko

Fully agree with Adam better bang for your buck...

Jacko.

WREXY

I have been told that the STI version 5 & 6 intercoolers are identical to the MY99/00 UK spec intercoolers and that it is only the colour that differs. Would someone be able to varify this please?

Cheers,

Wrexy.

Jacko

Hi Wrexy, I also thought this but I was told that they had to be the same size and shape so as they can be directly interchangeable. However, I was also told that the internal core is different and more efficient?????
Anyway, I have obtained good results with my STiV TMIC, only cost £200
Next tweak will be waterspray+waterinjection for the summer months, possibly bigger injectors when needed to cope with a FMIC later this year....
Tweak after that will probably be closed deck block with forged everything to replace the resultant abstract artwork under the bonnet (conrods etc. hanging out the engine!)

Jacko.

[Edited by Jacko - 1/15/2002 12:05:59 PM]

WREXY

Cheers m8,

Sounds interesting. Good luck with your mods!!!

Wrexy.

mutant_matt

Scott,

Uprating the IC can deffinately make a serious difference to the power produced. At the moment, with the brass monkey weather outside, how good does your car feel compared to the summer? Quite a bit better I would say

Check out this thread for some examples of just how much of a difference they can make:

What inlet temps you FMIC boys running?

Well, a new IC can give you those kind of gains, throughout the year. The question to my mind is, can any of the uprated Top Mounts make enough difference to make it worthwhile? The APS one is worth checking out (IMHO) and so is the one that Cossie Convert mentioned in this thread:

Radtec Racing Radiators TMIC Thread

Anyway, speak to you on Sat @ PE about it....

Matt

RB5SCOTT

Mmmmm, gives me something to think about. I don't really want big power gains just a more effecient intercooler(especially in summer)which i believe the slighter larger STI7 intercooler will give me

If Jonno get his APS kit with FMIC i am 1st on the waiting list for his STI7 intercooler so quite a cheap and easy mod

Jacko, mines ugly but yours is slow lol

Scott, I will be racking a few people's brains on saturday

rollerskate_01

Scott

Had you considered the STI7 air scoop. Bigger than MY01 standard.

RB5SCOTT

Roller, I've got a Scoobysport carbon fibre one on order

Pete Croney

This is an interesting subject. The STi 7 intercooler is bigger, but its also bigger than the hole in the bonnet. The skirt below the scoop is the same on both models. Is there any benefit in having extra core area, if it doesn't get any airflow over it?

Also, on the new car, the bonnet is a substantially different shape and scoop airflow is much better. The STi scoop will make a considerable difference in airflow and will ensure that airflow rates are maintained at high speed.

===

Some interesting/controversial points about intercoolers...

1) We have done engine rebuilds/swaps on over 80 Imprezas. Most are STi, many are WRX, 2 were UK cars. None had front mounts.

2) Of the engines that suffered failure of a bigend bearing (almost all of them), all had been used at high speed (over 120mph) either at the time of failure or very shortly before it.

3) The 99 and 2000 WRC cars had the airfilter positioned just below the bonnet scoop. You would have thought that they would have taken intake air from the scoop. No, it was blanked off and they ducted air from the front of the bonnet.

4) The 2001/2002 WRC car uses the scoop for the intake air feed.

Summary:

A) On the pre 2001 car, air would appear to delaminate from the bonnet, completely missing the scoop once a certain speed is exceeded. This causes a massive and sudden rise in intake temperature.

B) The bonnet shape has been corrected on the 2001 and now even has enough constant scoop pressure for it to be used as the airbox feed.

C) A FMIC may actually be essential on a pre 2001 that is used at very high speed.

D) Wind tunnel work would be required to determine the speed at which air delamintes from the bonnet.


Just my own opinion.

Adam M

**** taking aside, a very interesting opinion Mr.Croney.

Are you going to be the on to tell pat that he should not have his airfilter beneath the scoop after he has just moved it there.

I wish someone would do this testing, this to me sounds liek a very interesting point.

But if it is the case that high inlet temps are responsible for the det that destroys the big ends, then why is there not more evidence of pitting on the piston crown, and why dont more cars fail on track where speeds often approach 140mph, load on engines is enormous and inlet temps dont get much time to reduce back to normal levels?

I am not criticising here pete, it is nice to here another theory, I am just putting forward some niggles with the theory.

Pete Croney

Adam

I have also thought this. But... there are not many places on UK tracks where you can exceed 130mph and even then it is only very briefly. The time period at this speed (and we are assuming that 130 is fast enough) is so short that it is almost certainly not long enough to overwhelm the intercooler.

As an example, consider Mark's car. Water injection, Link, more gadgets than Hamleys... and an uprated top mount.

GavinP

I've said it before but I'll say it again - when it someone going to respond to market forces and produce a front-mounted IC kit for £500 ???

Cores are readily available for £200+VAT so I am perplexed why someone doesn't produce a hose kit (£300 would buy a lot of silicon hose or aluminium tubing )and corner the market....

I went for a chargecooler setup in the end for circa £500 as it works better for my driving (no track days, mainly urban driving) and I refused to have "my trousers taken down" for £1000+ IMHO

I have no doubt that the more expensive FMICs are excellent but there must be room to produce a more affordable solution.

Thanks

Gavin

[Edited by GavinP - 1/16/2002 6:45:08 PM]

CraigH

Pete,

It's funny you should mention the airflow over the scoop. Spoke to someone a little while back and I wasn't sure if it was a wind up....basically an Impreza Turbo had been tested in a wind tunnel (with the funny little cotton streamers (my tech description ) and above a certain speed, which I believe was quite slow, 70mph or less maybe, no air made it into the sccoop - it passed straight over and created some sort of turbulence that made the streamers aim towards the front of the car.....

Seems plausible to me. That would also explain why the WRC airfilter takes the flow from the front, as the scoop is redundant at race speeds.

So basically everyone needs to go out and buy a Front Mount!

Gavin,

Just because you can buy a core for £200, doesn't mean it's going to be any good. I wish these things were cheaper - is one of the best mods you can make imo.

GavinP

Craig,

Point taken - it's no good if it is £500 and rubbish but I still think there is some room to manoevre here...

The £200 example was for a core from a professional motorsport fabrication company in Demon Tweeks - not me in my shed!

Thanks

Gavin

Knowlesy

img]http://www.stopstart.fsnet.co.uk/aircraft/pigflymed.gif[/img]

Did you like my pig above...if it works....

I've got a new scoop on order with Pete though gonna have it painted Carbon's too much of a racer for me......

Knowlesy

mmmmm, that didn't go well..."I'll try another, bear with me now!"

RB5SCOTT

Knowlesy you muppet



lol

Dave T-S

Scott
If I remember correctly from the original sales blurb, the MY01 standard UK I/C is 15% bigger than the MY00<, and was basically an STI5/6 I/C. It probably doesn't need a bigger area, more the case of getting the air to flow through the core better, as covered above.

PS - my carbon fibre STI7 scoop was on order before yours LOL

NITO

YES!! FMIC!

ski

After a blast down your favourite roads,open the bonnet and touch the intercooler(top mount)to see if it is cold.If it is air must be passing through the core.The flow of air over a bonnet is attached so a good deal of it must go into the scoop.

Phil

knowsley

on your 1st post your missing the opening [

just edit your post and add it

It will work

BTW should never have given you that website


Phil

mutant_matt

Chaps,

Interesting theory. The thing is, from data I've seen in my car and this extract taken from this post ( IC Data ), the data would suggest that the intercooler is doing a fair amount of work still at speeds ranging between 80 - 100mph (and from a couple of all out runs I've done, the inlet temps at the throttle body didn't change beyond 40degC on a top speed run (but like Pete said, perhaps I wasn't running long enough for heat soak/lack of air across the IC to heat things up....????)If he's running in 4th @ 5500rpm and the turbo out is 160 and the inlet temp is 55-60 then the TMIC must have a decent amount of air passing through it to manage this????

Matt