Hi guys,
I have a JDM 2003 STi (Twin scroll) and am loving it J

It has a Powerstation power package on it which included a Miltek exhaust (Cat-less), K/N panel filter and ECU TEK remap, plus added was a 3 port boost sol and a walbro fuel pump. Dyno print out shows 355hp and 345ft/lbs, needless to say, it pulls like a train :-D

I just have a few problems…

First of which, seems to be if im running under ½ a tank of fuel (Always tesco 99) and have just booted it around a roundabout, when going on to the straight and floor it, as the boost reaches full (about 3600rpm) it will all of a sudden totally cut almost like a miss fire throwing me forward into the seatbelt. Obv when this happens I let off right away wait a few seconds and then try again and it is perfect again.

Im sure that people are going to say that it is boost cut (over boosting) but im not so sure, as it never does it with a full tank of fuel and it is only after coming out of a hard corner and flooring it hence throwing all the fuel to the side of the tank….. Under half a tank I am able to floor it with no problems if im on a straight.. so im confused…. L

My other problem I think is diff related so will post in that section when I get a chance.

Thanks for reading J
Cheers

 

Do you have anyway of knowing what boost you are running when this happens, gauges, monitor etc? I've never had this problem with my Spec C.

 

WOW!!! Now that was a fast reply :-)

I have a greddy profec b spec 2 (from my turbo civic days) which isnt installed but could wire it up just to read boost but unfortunately wouldnt be untill the weekend at the earliest :-(

 

Fuel Pump not picking fuel up under load had same with mine! Perfect on full tank but as soon as i hit half full i had problems, Removed fuel pump and cleaned in tank filter and modified to pick up lower problem solved no mising or cuting out round hard cornering or roundabouts even when near empty give it a try mate. Don't know why some have this problem and others don't though :s

 

Fuel surge!

 

How would I go about modding it? do you know of any guides for this?

Thanks for the quick replies, was always told scoobynet is the best

 

Zen do a very nice hyperflow fuel surge kit that will assist in getting rid of this down to much lower tank levels.

Uber Lean misfire is a dangerous thing to the engine - I would get it sorted asap.

 

Just had a look at that, a little bit more than I wanted to spend but if it cures the problem then it would have been worth it.

Would prefer to first of all try this modding thingy see if that cures it.

So I guess this is semi common with the walbro pumps then?

 

It is down to the design of the subaru fuel tank and the fuel pick up being in the drivers side of it. When going around right hand bends all the fuel moves away from the pick up and the engine runs massively leans for a second or two.

The hyperflow doesnt solve it completely, for that you would need a swirl pot but that isnt practical IMO on a road only car. The hyperflow kit does a good job though on road tyres.

 

Hmm, come to think of it, I havent noticed it doing it around left hand bends..

awww poo, looks like ill have to fork out the doe for one if I 'modding' it doesnt work!!

Any one know what this modding thing is? and if there are any guides?

Thanks again for all of your help and quick replies

 

Theres not a mod as such mate i don't think, i just used a suitable bit of pipework to drop the filter a little lower in the tank and that has cured my problem. As said above it's only really round right hand bends.

 

Lovely stuff!!

Cheers mate, ill give it a try and see what happens, if not spend a bit of £££ me thinks

Thanks again for all the replies guys, happy motoring

 

No probs mate like i said it's cured mine did a 150 mile drive yesterday with some hard cornering and it was superb, Good luck.

 

Try and find a s/h spec c fuel pump assembly, which has a surge protector (06> has anyhow). Basically, the usual box around the fuel pick/sock, open to the right rear corner, so collects fuel during r/h bends/braking..

It wouldn't be too difficult to fabricate one actually. Some ally sheeting, formed into a box open on one side, with a bracket to bolt to fuel pump assy bracket.

It would be what I'd be looking at doing, if I suffered fuel surge, which I don't..

 

Hi guys,
Still getting this problem and its doing my head in lol...

Ive come a cross a type 25 spec c breaking for spears, will this have the surge protector on it? If so how much do you think would be a reasonable price?

Thanks guys!

 

Price largely depends on the breakers knowing what it is..

If you say you just want the 'fuel pump bracket' and not the pump itself you might get it for a reasonable price..

What's reasonable is up to you really as aftermarket ones tend to be silly £200+ money..!

If I was you I'd phone Olly at Roger Clark and ask him for a guide price for a new one. Would be worth confirming with him which MY spec C's came with one fitted as standard.

Let us know how you get on..