harvey

iTrader: (48)

Absolutely not. Why would a front mountbe more stressful???
The front mount if you choose the right one, will give the engine cool air which is what it needs to develop safe power, however you must have the car mapped after fitting the frontmoint. It will be LESS stressful for your engine.

Please read what has already been posted.

harvey

iTrader: (48)

Sabas/555EFC : Guys, you really need to read what has been posted before and digest it so you have an understanding of what we are telling you.
I am based Darlington. ACT guages ie. Air Charge Temperature guages are £82.50 each as already stated in this post previously. You can probably fit one yourself. We could fit one by appointment, while you wait for £30. The sensor goes just before the throttle body and this will take out all the guess work as to whether your top mount is working satisfactorily or you need a front mount and you will also know if your front mount is working satisfactorily. The objective is to get the air entering the inlet manifold at the throttle body as close to ambient temperature as possible. Typically with a top mount when you are giving the car large, even with an STi 8, you can easily see 40 odd degrees and sometimes 50 degrees with WOT (Wide Open Throttle) on a long straight. With an efficient front mount that temperature will typically be 6-12 degrees over ambient so let us assume your in car temperature guage is showing 16 degrees then you could expect to see 22-28 degrees on your ACT guage. The lower the ACT the more fuel the engine requires and therefore the more power but at very high ACTs your ECU may pull timing to protect the engine. This is unlikely to happen with a front mount.
My opinion is that at 420 bhp you will already be suffering high air charge temperatures in the 40s round the Nurburg Ring but rather than rely on my judgement, fit a guage for £82.50 and if your temperatures are in the 40s you need an FMIC. If your temperatures are in the 30s, chances are the expenditure is not worthwhile at this moment in time.

Now there is enough information here from Splitpin and myself to let you guys make your own minds up as to what you do. If you have any more questions because we have overlooked anything let us know but it is down to you to decide whether the information we give is based on years of hard experience and whether you want to benefit from it. Intercoolers are something I have been heavily involved with both front mount and top mount for over 10 years.

Sabas

iTrader: (22)

Thanks for the replies, just want to make sure I make the right decision, with the FMIC , do you need to get another dump valve or can you use an existing one? Thanks

harvey

iTrader: (48)

Use the existing one with a flange adaptor which can be supplied at the same time as the FMIC. £26.50.

harvey

iTrader: (48)

Ignore that last post as you have a 97 car. You can use the existing BOV no problem along with the FMIC.

Sabas

iTrader: (22)

forgot to add, I already have an apexi induction kit, so would fitting a cold air feed for that at the same time help?

Toffee

iTrader: (3)

Harvey / Splitpin, thanks for the detailed response fellas, as stated I have already made engine bay mods which see me at 420hp, I am just fitting a set of Rays & AP brakes. next on list is suspension and then I will be coming back to the engine again > something like a 2.5 cosworth short block? not sure yet but its a while off anyway.

I just wanna make sure that my engine can hang in there until its upgrade time. after reading your advice I will be getting an ACT Gauge fitted I will be back in touch when its time for a FMIC

Thanks,
Lee.

harvey

iTrader: (48)

Anything you can do to give cold air to the engine will help. An inner wing CAK is not the way to go however, certainlyl not for big power. You want the biggest filter that will fit in the space available and if you can shield it from the hot engine bay and encourage in cold air that is a good move.
Cheers 555EFC. Air charge temperature guages in stock if you want one £82.50 posted.

milliemoo

Harvey,you say the biggest filter you can get in the bay is best!does shape of the filter matter also and what do you make of these closed box systems that some companys sell? (just curious really)

joz8968

iTrader: (13)

millemoo it all about the filter's surface area - so the biggest that will fit in an appropriate place. This in itsellf will invariably dictate the filter's shape e.g. fat cone/long cone/long thin straight/short fat straight, etc, etc.

Again, it's not the shape that matters, but the overall surface area the particular filter offers. The greater the surface area, the more "future proofed" you are to allow for big airflow/potential big bhp.

harvey

iTrader: (48)

The filter can be cylindrical, parallel, or it can be a cone but it needs to be big enough to flow in excess of the air for your horsepower without a depression in the inlet manifold. I use Magnahelix guages to measure the depression in the inlet tract and large depressions are a result of small filters.
Secondly, it helps if the air has a smooth flow from the filter into the inlet tract and for that reason I always use a trumpet with radiused edges wherever possible.

milliemoo

Yeh ive seen these radiused intakes on other applications from a mini 'stub stack' (i think thats what they called them!) to some lovely spun alloy types.

Can a filter be TOO large??and why do companys use inverted cones,is this for more surface ares?

Sabas

iTrader: (22)

is an apexi filter okay? Currently on the car already

Tidgy

sorry for slow reply, totaly forgot about the thread.

not as such for hot climate, but harveys posted up the difference in inlet temps, so higher ambient temp means higher inlet temps.

as far as power figures based on a test then jap performance mag did one a while back (few years now) and agreed with harveys results.

the link is on scoobyclinics website

Toffee

iTrader: (3)

I bought an RCM induction kit, it looks fairly big! I dont like the look of the CAK with a hole at the front where the STi badge should be so decided on engine bay kit. I am getting car mapped again next Thursday at Powerstation, at present it is 420bhp/348torx, prior to the new turbo it was 346bhp/377torx? cant understand why with bigger injectors 450cc>800cc, induction kit, bigger turbo & an increase in boost from 1.45>1.50 the torque has dropped?

Harvey I will be in touch for a gauge as soon as finances allow, what is your shop name? what am I searching for on google?

Lee.

harvey

iTrader: (48)

What shop? I operate from home/my garage. Harvey Performance. You can get in touch by emailing me harveysmith1@btopenworld.com or PM on here.

Toffee

iTrader: (3)

simon57

iTrader: (2)

Having a ACT gauge will stop you giving it beans if you've been stationary for a while.

made me understand alot more on whats going on in my engine.

harvey

iTrader: (48)

Very wise words Simon.