Walbro 255; stock FPR?

[Eclipse98_RS]

Ok, first off I did a search and couldnt find any of these two linked together and I had a question about it. I am going to be getting a walbro 255 in my car very soon. The question I have is " If I have 550cc Injectors, and a wally 255, will it overpower my stock FPR?"
Any info is welcomed, and like I said I did a search and couldnt come up with anything, so if you find some info please point me towards that.
Thanks,
-Dan

 

[SnowBird]

If you arent planning on running 10's or close to 500HP, you shouldnt even consider getting a 255. You dont need it.

 

[oldman]

If you arent planning on running 10's or close to 500HP, you shouldnt even consider getting a 255. You dont need it.

Again, more mis-information, mind showing us your mathmatical calculations for your statement?

 

[tsiawd1995]

Like I said I have no overrun at all and I do have a fuel pressure gauge. So you are giving the mis-information.

 

[oldman]

Like I said I have no overrun at all and I do have a fuel pressure gauge.

Then go back an check your fuel pump installation (mainly the o-ring and spacer), fuel pump itself, clogged filter...etc., , it is physically impossible for a 255 not to overrun the stocker if the rest of the fuel system is functioning properly.

 

[tsiawd1995]

Then go back an check your fuel pump installation (mainly the o-ring and spacer), fuel pump itself, clogged filter...etc., , it is physically impossible for a 255 not to overrun the stocker if the rest of the fuel system is functioning properly.

Have you tried it on a 2g. I know about 5 other 2gs that have no afpr on a 255hp and what do you know no problems.

 

[oldman]

Have you tried it on a 2g. I know about 5 other 2gs that have no afpr on a 255hp and what do you know no problems.

I have both 1G and 2G and I have installed 255/AFPR on countless 2Gs locally. The average overrun on a 1G is about 12-15psi at idle, 2Gs are a little better but not by much.

 

[tsiawd1995]

I have both 1G and 2G and I have installed 255/AFPR on countless 2Gs locally. The average overrun on a 1G is about 12-15psi at idle, 2Gs are a little better but not by much.

I too have had both and done countless others and only had overrun problems with 1gs. I say try it if you have problems overrunning at idle buy a afpr.

 

[oldman]

I too have had both and done countless others

And all of them were installed with a fuel pressure gauge? Maybe you installed all the pumps the same way and the o-rings are torn, extra cranking during cold start would be a clear indication of a faulty install. In some cases, a 2g is actually worse because the return line itself, not just the FPR, can be an issue.

This is like talking about venting, you can always find bunch of people claiming "I've been venting for years without any problems", physically impossible.

 

[tsiawd1995]

And all of them were installed with a fuel pressure gauge? Maybe you installed all the pumps the same way and the o-rings are torn, extra cranking during cold start would be a clear indication of a faulty install. In some cases, a 2g is actually worse because the return line itself, not just the FPR, can be an issue.

This is like talking about venting, you can always find bunch of people claiming "I've been venting for years without any problems", physically impossible.

I guess I just installed them all wrong sorry guys you do need a afpr. I guess I need to find a mechanic for my 11.3@127 2g and my 10.8@132 1g because I apparently can't install fuel pumps .

 

[WOTDSM]

Quick question... Don't mean to threadjack but what's the verdict? Can a 255 HP ruin injectors? Reason I ask is because my car has a NASTY mystery misfire and an idiot that owned it before me had a 255 HP in it with no FPR. So could I have a bad injector? If so, its not a big deal since I have 550's and a 2g mas sitting right next to me...

 

[oldman]

I guess I just installed them all wrong sorry guys you do need a afpr. I guess I need to find a mechanic for my 11.3@127 2g and my 10.8@132 1g because I apparently can't install fuel pumps .

FPR overrun has little to do with WOT tune and running fast times doesn't automatically make you an expert mechanic, in most cases, the faster one run at the track, the less one cares about drivability. You didn't answer my question, do all of them have a fuel pressure gauge installed? Does your pressure on your 1G w/AFPR drop to 0 immediately after shutdown? If you truly had a fuel pressure gauge on your 2G, why would you say "no signs of overrun" instead of "no overrun" in your first post?

 

[oldman]

Quick question... Don't mean to threadjack but what's the verdict? Can a 255 HP ruin injectors? Reason I ask is because my car has a NASTY mystery misfire and an idiot that owned it before me had a 255 HP in it with no FPR. So could I have a bad injector? If so, its not a big deal since I have 550's and a 2g mas sitting right next to me...

Misfire can be caused by rich conditions -> FPR overrun, you can definitely use an AFPR.

 

[WOTDSM]

Well I swapped it out for a 190lph. I was just wondering if the 255 has caused some damage.

 

[oldman]

Well I swapped it out for a 190lph. I was just wondering if the 255 has caused some damage.

Not to the injectors no. The main concern for running rich constantly, especially during idle, is excess fuel washing away oil (lubrication) on the cylinder walls.

 

[Smevans]

Not to the injectors no. The main concern for running rich constantly, especially during idle, is excess fuel washing away oil (lubrication) on the cylinder walls.

I'm Hijacking for a sec (sorry)


oldman, I'll listen to you over most people on this site. You may have solved a question of mine. I've been driving my car without an AFPR for a while (30,000kms roughly) and definitely have problems with overun. My oil level drops after driving for awhile (I typically need to add a litre or two) so I'm wondering if it's getting washed away? There aren't any leaks where I park my car which I would think be a sign of it leaking elsewhere. I should have my AFPR in the next couple of days .

 

[oldman]

I've been driving my car without an AFPR for a while (30,000kms roughly) and definitely have problems with overun. My oil level drops after driving for awhile (I typically need to add a litre or two) so I'm wondering if it's getting washed away? There aren't any leaks where I park my car which I would think be a sign of it leaking elsewhere.

Short answer is "no" because oil is being washed down to your oil pan, with that said, excessive ring wear due to lack of lubrication will increase oil consumption. Since you're not seeing any external leaks, you should start looking for internal leaks, piston rings, turbo seal, valve seals and PCV valve. Are you smoking out of your exhaust?

PS What are km and liter.

 

[Smevans]

PS What are km and liter.

My bad American.

At idle my exhaust looks normal although it is spitting out unburnt fuel and I do have it on my bumper. It does burn rich and the exhaust turns black at WOT. I had my pcv valve off the other day, it seemed fine. What should I look for? I'll have a look at things. Thanks.

 

[oldman]

I would start with dry and wet compression test, check your turbo for shaft play then perform a boost leak test with oil cap open so you can listen for leaks under the valve cover (PCV and intake valve seals). AFPR should take care of you rich idle condition, assuming the your Eprom/680s/safc are properly tuned.

 

[Smevans]

I would start with dry and wet compression test, check your turbo for shaft play then perform a boost leak test with oil cap open so you can listen for leaks under the valve cover (PCV and intake valve seals). AFPR should take care of you rich idle condition, assuming the your Eprom/680s/safc are properly tuned.

Excellent, thanks for the link too. My Eprom is tuned so once I have the AFPR I'll play with the AFC and my knock gauge.

 

[TSIMonsteR]

Oldman, I am sure glad you came in here to do away with this mis-information.

You are right, this is exactly like people who vent their blow off valve....

 

[Eclipse98_RS]

So does that mean if I have no black soot on my rear bumper that Im running in the correct range?

 

[oldman]

So does that mean if I have no black soot on my rear bumper that Im running in the correct range?

Sounds like your mind is already made up on not running one so go ahead with it, 2 pages of info and you choose to pick one little statement that fits what you were looking for.

 

[EclipseTrbo420A]

So does that mean if I have no black soot on my rear bumper that Im running in the correct range?

Not running a regulator is like entering an infant in fightclub.

DSMParts.Com Bolt on fuel pressure regulator. 149.99 http://www.dsmparts.com/customer/product.php?productid=403&cat=&page=1

Summit for the gauge 17.95 http://store.summitracing.com/partd...art=SUM-800199&N=700+-127729+115&autoview=sku

If anything, forget it all and do it to save the gas at idle...the prices will never go below 2.00 a gallon again.

 

[elfroggo]

I'll ask some questions then.

I don't think many people are saying they have no overrun, rather they are skeptical that overrun is hurting their car.

Isn't idle a consistent condition? It won't be "load based" or affected by "non linear" changes.

I'll use dsmlink as an example. If you notice that your LTFT lo's were maxed out subtracting fuel wouldn't that be a clue of overrun? If at idle you had a wideband installed and it was reading very rich wouldn't that be a clue of overrun?

Now what if at 50hz airflow slider you starting subtracting airflow? Of if you had a wideband and tried to tune for 14.7 at idle using airflow sliders.

I must say I'm rather disappointed, the amount of mis-information on this thread is just rediculous, some are coming from experience members.

1. 255 or 190 (to a lesser degree) will overrun stock fpr's, 1G or 2G. If you're running without an AFPR and you have a gauge to prove you have no overrun, something is wrong with your fuel system. I'll go ahead and say that most of you claiming no overrun doesn't own a fuel pressure gauge.

2. Much like you can't tune out venting a BOV with stock MAFs, you can't tune out FPR overrun. Why? Because the changes are NON-LINEAR and load based, anyone who claims they can tune it out, please provide detail information as to how, it would be the first.

 

[Smevans]

I got my AFPR today After a year... what a moron .