westmore

hello

i have a impreza 2000 turbo its a 1999. V reg

i have got a front mount on my car and just put a boost gauge on and its reading 9 psi ???

what sould it b? thanks
alan

TonyBurns

iTrader: (3)

Do you have any other modifications apart from the front mounted intercooler?

Tony

westmore

K&N but iv had to tape half it up because it was messing the MAF up lol !!

Splitpin

The target is 13.6psi up to 5000rpm. It should, in practice, hold a fraction under this. 9psi is wrong - assuming your gauge is accurate. It's wrong in an odd way though. It's clearly underboosting, but is a little higher than one would normally expect actuator pressure to be.

WTF? In what way exactly was it "messing up the MAF"?

If the cone filter is mucking about with your air flow meter, removing it is probably the best option. If by "taping half of it up" you mean you've wrapped tape round the element to reduce its surface area, you will probably be making things worse in some other way.

To put it bluntly this sounds like a bodge - and bodges in this area have a nasty habit of costing a lot of money. Standard induction and panel filter would almost certainly produce more power than this setup.

Best thing you could do on the basis of what you've said so far is to refit the standard induction tract, or else see a mapper who will be able to determine whether the sensor is being vibration-afflicted or simply needs rescaling. Will probably be able to diagnose the boost control issues at the same time.

westmore

i have an on going problem with the engine.

i rebuilt the engine a little while ago and my m8 gave me his front mount and k&n, after running it in and giving it a good service i put my foot down and it didnt run rite.
i fort it was a boost problem so i got a boost gauge it see what is was boosting at, but have worked out that the k&n is messing up the maf. i went to put the air box back on but it wouldn't fit because of of the front mount piping. so i put tape round the cone of the filter to restrict some of the air getting in to see if it would run rite. so i no i need a remap it, or put the air box back on or get a new maf. thats why there is tape on there.
thats why i was asking about the boost to try and getting running better.

Splitpin

Yes, had twigged that bit. The problem is that you have no way of knowing at this point whether it isn't running right because of the front mount and induction kit, or because of some other reason. Running a process of elimination involving the removal of both the IC and the cone is probably where to start. Neither of them is doing your car any particular good anyway the "partial cone" in particular.

How have you worked that out? Have you actually monitored the MAF sensor voltage, or the boost AFR or something similar?

As above is there any reason you can't just take the pipework off as a test, refit the standard induction tract and TMIC? As a troubleshooting step, at very least, it's worthwhile.

Yikes. That's about the most backward bit of troubleshooting I've ever heard. Sorry dude but trying to limit the area of the cone under these circumstances is not going to solve any problems, especially given that there are two or three different ways that cone filters can negatively affect MAF accuracy - on 99-00 in particular.

The engine will continue to try and suck in however much air it can get, so by limiting the cross-section of the filter element you'll be increasing the air velocity through the part still in use, and thus will affect the flow through the MAF element to some extent, but the effect will be totally random, and, unless you're logging it, you have no way to ascertain what it's doing.

Bottom line is that fitting an induction kit and then masking part of it off is almost literally cutting your nose off to spite your face. The whole point of a cone is to increase the cross section of the filtration area in comparison with a panel!

If I were in your shoes, the first thing I'd do is get rid of the IC and induction kit and put it back to standard, and then see what happens to the boost.

You already know that the engine isn't running right. Mucking about with bits of tape in the meantime is more likely to blow it up than sort it out. If you think there's a chance that the airflow meter has been permanently damaged as a result of this experiment, fitting a new one at the same time is probably a good idea.