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Dodge Daytona 4 bar fpr

https://www.ebay.com/itm/For-1984-1...sure-Regulator-47528YG-1985-1986/183876816774

Says it fits the turbo daytonas.picture shows the opening into the fuel rail is different looking than ours. With a long barb instead of a short opening with an o ring. Wanna put it on my 740

Wrong one for your car.

Don't adjust the fuel pressure from stock unless you know EXACTLY what you're doing.

This is a 3.8 bar fuel regulator that will bolt to a Volvo fuel rail.
https://www.ebay.com/itm/New-Fuel-P...:NPQAAOSwwFlcgU9r:sc:USPSPriority!85204!US!-1

I install a 3.0 bar fuel regulator so I can lower my fuel pressure to allow more fuel volume.
 
Eh, I know enough of what I'm trying to do...thanks though. I realized it comes from an 88 or newer maybe? Different designs of fuel rail, got the right part now.

On rock auto #4306015

And that is a better idea. Thank you sir. Exactly what I need 3.8bar

I have t5 injectors that are stock at 3.8 bar...but it's coupled with the 3 bar volvo fpr
 
Lol that's cool. I know I'm changing the fuel pressure to what these injectors normally run under stock conditions...in a not so stock car.

Criticize all you like, but at least throw some useful knowledge instead of tryingbe a troll (like what I did there?
 
Lol that's cool. I know I'm changing the fuel pressure to what these injectors normally run under stock conditions...in a not so stock car.

Criticize all you like, but at least throw some useful knowledge instead of tryingbe a troll (like what I did there?

Why do you think you need to change your base pressure?
 
At 18 psi all is good but if I have a spike (which I'm battling rn) then I hear pinging. I have chips in ezk and ecu, npr IC, strong spark, so need more fuel, yeah?

Also when I first installed these injectors ~1.5 years ago, I didn't consider they are measured at 3.8 bar. So not only less fuel but potential to mess up spray pattern? Figured it will put it back to the way it's meant to be (3.8 bar fpr paired with these injevtors) and most likely solve my pinging at high boost.

Was going for the "4bar" dodge one but it's 55psi..which is 3.8 bar really.
 
At 18 psi all is good but if I have a spike (which I'm battling rn) then I hear pinging. I have chips in ezk and ecu, npr IC, strong spark, so need more fuel, yeah?

Also when I first installed these injectors ~1.5 years ago, I didn't consider they are measured at 3.8 bar. So not only less fuel but potential to mess up spray pattern? Figured it will put it back to the way it's meant to be (3.8 bar fpr paired with these injevtors) and most likely solve my pinging at high boost.

Was going for the "4bar" dodge one but it's 55psi..which is 3.8 bar really.

Right, so you?re just bandaiding it. LH is expecting 3bar.

Just get the right injectors.
 
When you say bandaid, are you meaning temporary vs. Permanent? Because I'm sure this will be enough fuel for my needs and will be permanent. Or do you mean ghetto/hacked? I would say putting a 3.8bar fpr on the stock injectors to make them flow more sounds pretty terrible, but matching fpr to injectors? Sounds about afar away from hacked as it can be. And is Lh2.4 really expecting 3 bar of fuel pressure? Considering it takes into account AMM readings and o2 readings to ADJUST accordingly. I'm sure it'll be fine, as have the thousands? Probably thousands that have ran this fpr before.

And the right injectors....like 42lb green giants? Because it really seems like switch from stock to those is a lot like what I'm doing with mine. Considering Lh2. 4 takes o2 readings and adjusts fuel trim, raising pressure to increase fuel output is a lot like changing injectors that flow 20% more than stock...

Even though I'm not raising it above stock levels for thsee injectors.
 
Nevermind spray pattern or what "lh is expecting". Remember that your fuel pump is working against both the base fuel pressure AND the boost pressure in a boost referenced fuel system.

An example:
with 55psi fuel pressure and 20psi boost a walbro gss341 only delivers around 45gph @12v. And ~55gph @13.5v.

A stock bosch inline pump for 7-series only delivers around 32gph at these pressure levels...
 
Hey hey, someone that might learn me something...what would you suggest is "enough" gph? With you saying "only 45gph" makes me think the stock one won't do with only 32gph.

There's not much talk of fuel pumps compared to what size injector and what not.
 
Okay...so after some reading up on fuel pumps vs injevtors vs FPRs, the smart thing to do would be to get bigger injectors. Like said above, less pressure = less strain on the pump and that's pretty much it. You have to have the pump able to produce enough fuel against pressure.

That being said, as my car sits, on the very high side with everything going right is 260hp at 20psi. At that hp the GPH needed to be "optimal" is only 27 GPH, below the stock pumps capabilites. If they are old, well yeah, it's probably not a great idea, but if they are new and strong 32 gph should be more than enough...at these power levels. But this would make a great time to upgrade to a walbro255

Also, should've searched before posting...found a 2018 thread with you both in it...posting the same stuff. Thanks for getting me interested in researching this stuff, rather than just sticking a it on there and sending it.
 
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I use t5 injectors with a stock fpr and it pulls hard with a 15g at 20psi, also chipped using a nimsport chip. Both pumps are stock. Maybe one of your pumps is going out, or your lines have some crap in them
 
I use t5 injectors with a stock fpr and it pulls hard with a 15g at 20psi, also chipped using a nimsport chip. Both pumps are stock. Maybe one of your pumps is going out, or your lines have some crap in them

Both pumps have been replaced in the last few years...not saying they aren't going bad but I'd like to hope not.

It's also hard to believe at almost stock levels you can run 20 psi without running out of fuel. The t5 injectors at 3 bar only have 33lbs or 354cc. Do you have a wideband? Mine pulled hard, and if it wasn't for the lean spike in the beggining of the pull I wouldn't mess with it.

Wonder if I should look into different chip options or an ostrich...
 
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Both pumps have been replaced in the last few years...not saying they aren't going bad but I'd like to hope not.

It's also hard to believe at almost stock levels you can run 20 psi without running out of fuel. The t5 injectors at 3 bar only have 33lbs or 354cc. Do you have a wideband? Mine pulled hard, and if it wasn't for the lean spike in the beggining of the pull I wouldn't mess with it.

Wonder if I should look into different chip options or an ostrich...

LH2.4 stock has lean spot. Chips fixes that.
 
the ping is not likely because you're running out of injector. That would be what you're band-aiding. How about some actual data? what's the afr at 18psi, and when it spikes? Any idea what your timing looks like at those load points?

what cam? what rpm range are we talking about here? You're putting a lot of faith in a system that it sounds like you don't understand, but are happy and willing to jack with the same system.... that you don't understand. this is at best an inadvisable course of action.
 
the ping is not likely because you're running out of injector. That would be what you're band-aiding. How about some actual data? what's the afr at 18psi, and when it spikes? Any idea what your timing looks like at those load points?

what cam? what rpm range are we talking about here? You're putting a lot of faith in a system that it sounds like you don't understand, but are happy and willing to jack with the same system.... that you don't understand. this is at best an inadvisable course of action.

Well, there's no point in arguing with the you...it's known you do know what you're talking about. So any suggestions would be much appreciated...

Before putting on the new fpr it pinged as soon as boost hit, around 2500 rpm, AFRs go from crusing (14.7ish) to low 12's, after spike AFRs drop to low 11s high 10s. After about 4k rpm it's dead rich, below 10.0. Pressure tested the system and pretty much no leaks.

I was also thinking the knock sends it into knock enrichment, cause the AFRs to plummet. But ya know, I'm probably wrong.

Ipd turbo cam. I'm not sure on timing.. ezk is chipped and running wasted spark. Timing on the cam is straight up.
 
Even though the fpr is a "band aid" or whatever, after putting it on and letting lh learn for about 500 miles, the knock is gone, but it's really rich in boost...suprise, richer than with the 3bar.

I have some green giants from my brother laying on the counter, when I do the blower motor I'll likely swap those in with the 3 bar fpr, but I do not have faith it will be any better in the high rpm range
 
I'm not arguing (or trying to), I'm trying to point out the fallacy in the thought process that's causing you to want to increase head pressure on the fuel system.

low 12's is not too lean for boost onset. hell mid to low 13's is fine for the first couple psi.
low 11's to high 10's is absolutely not lean
10.0 after 4k is wasting fuel and thinning out your oil.
whether it's hitting knock enrichment or not is irrelevant at this point. What's it do if you roll in to it and let it spool up slowly?


So let's think about this for half a second:
Your current system, regardless of what it's doing when it starts pinging, has enough overhead to get you past the point of diminishing returns and likely to the point or beyond the point of drowning the fun in fuel.
With that in mind, why would you want to add more fuel?
I generally don't tune stuff to run lower than mid 11's on pump 93 until it's 1) above 18-19psi and simultaneously 2) above 400whp. Even then I might not depending on what the setup likes. It's very much dependent on the setup.


looked at the plugs lately? What chips? Are the chips even appropriate for what you're currently doing? Tried a different MAF? You don't have enough data to pinpoint the issue at this juncture, throwing parts at it is not likely to get you anywhere. boost onset knock is a common issue with small turbos on lh 2.4
 
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