Hi guys,
I have got a big turbo in my car and normally you would think it spools up to the top, but I had to see that it is not possible either with the SR40 nor with the new bigger turbo.
Boost drops from 1.7bar to 1bar after 5700rpm.

What do you think is the problem?

I will go for a ride with an mushroomfilter instead of the stock airbox and paperfilter.
Hope that will solve the problem.

Anyways has anybody got another idea?

I have got a 3" downpipe and the stock 2nd cat and an Laser backbox that is very good and near a straight through!

 

geta remap m8 you must be the stupidist person on here lol

 

Could it be due to the 2nd cat causing back pressure?? And the fact it also tapers to 2.5" also. I would have thought on a big turbo this would become very restrictive.
You could always remove the centre and back box and see what difference it makes to the boost.

Mike

 

Why are I stupid?
No need for a remap, my car is not mapped perfect yet, but this does not affect boost in any way!

I solved the problem by using a mushroomfilter in the enginebay now, but would like to stick with the stock airbox and uprated filter.
Turbo boost up to redline without any issue!

Which airfilter is a good choice on a high horsepower engine?
It should not be oiled because of using the MY99 MAF.
Any advice?

The exhaust seems to be up to the task even with the 2nd cat in.

 

Ignore scoobzie's post......it is he that is stupid.

Glad you got it sorted mate.

As for the panel filter im sorry I cannot help you with that one.


Mike

 

I think even a stock airfilter can not be much of a restriction. Your old filter must have just been clogged. Simply replace with a new filter and you should have full boost till redline.

 

I just changed the filter some days ago and it is near new!
I did not use the restrictor anyways.
Maybe the elbow I made from an aluminiumshrinktube into the enginebay.
(Hope you understand what I mean, I made an elbow from the airbox to the drivers (RHD) light in the enginebay)

 

The Uprated STi filter (with the stainless steel mesh cover to prevent it deforming under high airflow) would probably be the best bet, but I am not 100% sure it will be up to the job of flowing the sort of air you will be looking at. Here is a pic of the filter Roger Clark Motorsport - RCM Product Detail

No scoobzie, you have that honour. Austrian Impreza actually maps his own car.

 

I would not recommend anything other than either a standard panel filter and airbox or something like an aftermarket green panel filter or maybe STI as mentioned. The green panel filters do not need to be oiled.

The above filter type is probably the best thing to do if you have a MY99 as the MAF on this model year is extremely sensitive and become faulty very quickly - which I think you mentioned.

Their is a way around it to have a cone filter on the MY99 but it has to be programmed into the remap to make the MAF redundant.

As to the boost issue, I'm very sure it will not be due to the stock paper filter and airbox - I would leave that as it is. Hopefully someone else will be able to advise you why the boost level drops to that level though. I

 

sounds like a samco pipe sucking itself closed

 

Thanks guys good to hear you do not think the same as scoobzie says!

I have to thank Alan (AL99) for his help sp far and for the future!
He is someone who knows what he does!

I also thought the filter should not be the problem, but due to changing to the aircone my boost problem went away!
Now I will give it a try with the stockbox and uprated filter maybe again with the stock paperfilter.
I made some kind of elbow sucking air from the enginebay, should leave this away and just suck air from the inner wing!

The samcopipe was my thought too, but due to the change I´m pretty sure the paperfilter is the problem...

 

Hi!

Just sent you another map now, tweaked fuelling to remove about 0.5 AFR off the top and midrange boost buildup, also some changes to ignition to help spoolup.
thanks for the kind words, glad to be of some help.

AL99

 

I'm not sure: he has some stiff competition...

 

Ooo Matron

 

Thanks for your help and knowledge and advice Alan!
Will test the map asap!

Does anybody know what happens when the MAF is going to die?
I had a faulty MAF on the stock ECu and the engine did not rev up anymore and the car ran very bad like on 3 cylinders.

The MAF was damaged when I had the Power FC in as well and the car did not start up any more, is this a safty feature?
Does the Apexi Power FC know when the MAF is going to read bad numbers and becoming faulty?

 

Can someone explain to the OP that this post supports him, he is struggling with sarcasm/irony in English...

 

Sorry my fault I understood the post the way you meant there are some more stupid users outside not only me!

All the best and sorry again!

 

The K+N induction kit is the most MAF friendly for a MY99, as long as it is secured correctly.

 

Isn´t the K&N oiled?
Has anyone an idea if the Viper is any good?

 

http://img.photobucket.com/albums/v6...7e393e8lm5.jpg

 

Yes it is, doesn't mean it won't work though.

 

Allright, I always thought the oil is what destroys the MAF!

@New_Scooby_04: nice picture!

 

I believe its the vibration that the MY99's don't like, of which most induction kits introduce, the K+N one has been proven to be the most MAF friendly IK.

Improper (over)oiling of any filter can skew the MAF readings, granted!

 

That´s some information, many thanks!
If anyboday has got the Z32 MAF tables I would even pay for this!!!