Need to replace fuel pump in 03 Evo VIII. What to choose? Stock or any aftermarket one? No plans for mods for the time being but who knows...

 

If your not planning on mods I would go with stock just to make sure Mitsu doesn't whine about warrentee stuff (which they shouldn't anyway) but just in case. Besides that you know that the stock one will fit fine not leak and will be reliable even if its not the highest performance. Not to mention its probably cheaper for ya

 

Is Walbro pump any good? E.g.
http://www.myevostore.com/product_in...roducts_id=138

 

I think you might run a little rich... someone correct me if i'm wrong

 

walbro 255

 

Correct.

The Walbro will overrun the factory regulator a bit at WOT and you'll run a bit richer.

 

So what should be done to compensate it?

Can I put in in place of stock pump without any other mods or should I not?

 

I wouldn't. Your going to run richer then you already are without any type of fuel management.

 

I have the Walbro and the ecu was tuned for stock pump. Car is now running rich, and idles a little choppy.

 

If I put Walbro 255, what should I do to make everything work all right?

How to use it's higher output?

 

You'll need to retune your air/fuel ratios with an SAFC or an ECU reflash...

 

Will it itself give any increse of performance?

 

NO mate. it wont give you any more performance on its own. you will pronaly looes a little *** your engine will be running even richer than normal (reducing power). the stock pump is good for around 350bhp i think, and as other have said, it will fit and work straight out the box. there have been a few people that are not satisfied with the Walbros. some say they have packed up for no reason!

if you are planning on modding though, you may want to look at the SARD280 as well. a bit bigger and more exspensive, but i have heard they are more reliable!

thanks Chris.