Is it worth me purchasing an uprated Walbro 255 fuel pump to go with my Classic Impreza PPP?

 

AFAIK Not unless your current one is on the way out, no.

If you go for any power increases, it would be a wise investment and a remap, of course.

Ns04

 

Ok cheers. I am having the PPP installed (along with bax box and decatted centre) on Saturday and will only add a 100 Cell Sports CAT downpipe when I get one so will probably stick with the standard fuel pump, Unless anyone recommends otherwise for the PPP..

The kit I bought (2nd hand) had a fuel pump with it but I think it's a standard UK one which I'll sell on or keep as spare.

 

Well, put it like this, the original PPP upgrade didn't upgrade the fuel pump.....but then again, it didn't include a sports cat in the DP IIRC too!

When you say you're having the PPP installed, what bits exactly are you having modified? Are you getting it custom mapped with Ecutek, or just fitting the ECU from a car that's been PPP'd? If it's the latter, the map won't be suited to a car with a sports cat DP!

ns04

 

It's a standard MY99/MY00 PPP so STI stamped Prodrive ECU, Prodrive Intercooler pipe, Back Box and Decatted (resonated) centre section.

Add to that the 100 cell downpipe.

Cheers.

 

To be honest I would fit a pump, they are only 75 quid or so. The car is 8 years old so the pump will have had some use. It's a cheap mod that gives you piece of mind. The engine leaning out at the top end is the last thing you want.

 

Yep, that and the addition of the decat DP which will mean you'll get more power from a remap than std PPP, I'd get one too! You will need a remap though, the PPP ecu is NOT configured correctly for the Sports cat DP, nor the uprated fuel pump.

Ns04

 

unless your having it custom mapped, and not the generic Prodrive PPP map then dont fit it, the pp map doesn't account for it

 

Thanks for the comments. I have over a week till the car goes in so will mull it over.

The downpipe won't be decat, but 100 cell, so faster flowing.

I thought the ECUs were self learning so would adapt to the different flow rate? I don't drive the car that hard or plan to track it as I have another car for that kind of thing. Will a remap be worth it? All I'm effectively changing is a slighter freeer downpipe on top of a standard PPP upgrade. I run the car on 99RON all the time.

 

it can learn to a certain extent, but not enough to compensate for the fuel pump, if your only going pp, then leave the pump be, not worth risking it cos it wont make any difference to the result you get.

 

But surely the pressure at the injectors will be the same due to the fuel reg.....yes/no??

 

no FPR on the ppp

buts its the same as when you uprate the turbo, changes AFR, the increased fuel flow is an issue

 

I will just have the PPP and sports cat downpipe fitted and leave it at that. If the fuel pump or anything else (MAF) needs changing after that I'll get it checked and act accordingly. Cheers.

 

nee probs, its only when you come to change the turbo the standard pump starts to struggle

 

It not just an issue of the car running lean with the DP it's also that you won't be getting the benefits from the DP running the generic PPP map, as it'll just adjust things to keep them within normal parameters for the PPP set up.

Custom map the way to go.

ns04

 

Sell the ppp ecu and get a custom ecutek map on your standard item....

Just a thought

 

I won't be doing anything massive in terms of peroformance mods and would be happy with the 240-250bhp the PPP and sports cat will hopefully offer.

As I've declared the ECU mod I could sell the Prodrive ECU and custom map mine but what extra cost could that incur? It sounds like a good option though and I could do this in a few months time.

As I said, I won't be racing or ragging the car so am hopeful that the PPP and sports downpipe will be sufficient and safe for the car.

Is there anything I can/should ask the garage (Subaru4you) that's fitting it to check on in relation to what we've discussed in this thread?
Cheers

 

I have exactly that set-up, ppp intercooler pipework, 100 cell cat resonated centre on exhaust, on a MY99.
The fuel pump will be fine as standard, ran mine for 3 years until the pump finally gave up, it now has a walbro 255 and still runs fine, FPR maintains correct fuel pressure in the rails.
I would get a knock link or some monitoring, because if it's a MY99/00 the MAF's are prone to failure.