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On 25/08/2022 at 1:21 AM, BK said:

I agree and get what you're saying, but only Nismo 280lph will ever be exact direct replacement.

I second this 100%. I replaced the stock pumps in my R33 GTST and my R32 GTR. It was LITERALLY a 5 min job in both occasions. Wasted a box of beers, as we only took like 3 sips :D

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14 hours ago, joshuaho96 said:

I’m definitely curious about going a similar route in my R33 once I have time to start messing with the fuel system. I really want to try running 997.1 Turbo EV14 injectors and a 440 lph brushless pump for an E85 conversion. I figure my comically tiny turbos should be enough of a limiting factor to get by on ~630cc injectors if I bump the fuel pressure enough. 

Why wouldn’t you just fit 1000cc injectors? They’re cheap enough, proven and any decent ecu can get them to run perfectly 

13 hours ago, joshuaho96 said:

I’m definitely curious about going a similar route in my R33 once I have time to start messing with the fuel system. I really want to try running 997.1 Turbo EV14 injectors and a 440 lph brushless pump for an E85 conversion. I figure my comically tiny turbos should be enough of a limiting factor to get by on ~630cc injectors if I bump the fuel pressure enough. 

(I'm guessing you are talking about the DeatchWerks DW440, I couldn't find any other brushless 440 lph pumps)

I'm also curious why you would want to fit a DeatchWerks DW440 440lph Brushless Fuel Pump, that flows less then a Walbro 525LPH and has extra wiring complexity, costs about 5 times as much, and knowing DeatchWerks, it doesn't have an internal check valve as it doesn't state that it has one.

On the plus side though, DeatchWerks has gone to the effort to put a retainer clip on for the fuel strainer, so that's nice. 

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1 hour ago, r32-25t said:

Why wouldn’t you just fit 1000cc injectors? They’re cheap enough, proven any decent ecu can get them to run perfectly 

Muricanaaaaaaaaa fuaaaakk yeah!

 

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3 hours ago, r32-25t said:

Why wouldn’t you just fit 1000cc injectors? They’re cheap enough, proven and any decent ecu can get them to run perfectly 

I really want a split spray injector to match the two intake valves. The easy route would be the 980cc 040 injectors that are everywhere but those are single cone. I thought maybe I was wrong about that when PRP claimed they weren’t the other day but I checked again to be sure. The difference is going to be minuscule but I’m pretty sure doing the math it won’t take too much of a bump in fuel pressure to have plenty of injector headroom.

7 hours ago, Murray_Calavera said:

(I'm guessing you are talking about the DeatchWerks DW440, I couldn't find any other brushless 440 lph pumps)

I'm also curious why you would want to fit a DeatchWerks DW440 440lph Brushless Fuel Pump, that flows less then a Walbro 525LPH and has extra wiring complexity, costs about 5 times as much, and knowing DeatchWerks, it doesn't have an internal check valve as it doesn't state that it has one.

On the plus side though, DeatchWerks has gone to the effort to put a retainer clip on for the fuel strainer, so that's nice. 

The main attraction for brushless IMO is no derate in lifespan for high ethanol use, lower power draw for more alternator headroom, and seemingly a flatter flow rate vs output pressure curve. I do wonder if the DW440 brushless will be any good or if I need to go searching for a better option. I don’t really need a ton of flow but I don’t want to worry at all about whether I’ll run out of headroom from excessive fuel line losses. Even 440 lph is likely too much flow for my purposes. 
 

6 hours ago, GTSBoy said:

f**k you're weird Josh.

I thought we established this with the choice of turbos no?

9 minutes ago, joshuaho96 said:

I really want a split spray injector to match the two intake valves. The easy route would be the 980cc 040 injectors that are everywhere but those are single cone. I thought maybe I was wrong about that when PRP claimed they weren’t the other day but I checked again to be sure. The difference is going to be minuscule but I’m pretty sure doing the math it won’t take too much of a bump in fuel pressure to have plenty of injector headroom.

The main attraction for brushless IMO is no derate in lifespan for high ethanol use, lower power draw for more alternator headroom, and seemingly a flatter flow rate vs output pressure curve. I do wonder if the DW440 brushless will be any good or if I need to go searching for a better option. I don’t really need a ton of flow but I don’t want to worry at all about whether I’ll run out of headroom from excessive fuel line losses. Even 440 lph is likely too much flow for my purposes. 
 

I thought we established this with the choice of turbos no?

The factory injector has a single cone spray pattern so by going to the 1000cc you’re not losing anything in the way of spray patterns 

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5 minutes ago, r32-25t said:

The factory injector has a single cone spray pattern so by going to the 1000cc you’re not losing anything in the way of spray patterns 

It’s more about modernizing the engine where possible. Reducing the wall wetting should improve transient response and emissions. 

Hmm ok. Really seems like you've dreamed up a bunch of problems that don't exist so that you have something to solve. 

When you look around, see every other skyline running perfectly, see that they don't have split spray injectors and don't have baby sized brushless fuel pumps.... How much "more perfect" will your car be? 

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2 minutes ago, joshuaho96 said:

It’s more about modernizing the engine where possible. Reducing the wall wetting should improve transient response and emissions. 

You realise that the majority of the time the injector is firing, it's spraying onto the back of a closed valve right? 

Are you trying to improve your emissions at idle?

I can guarantee that your transient response will not be improved by using a spilt spray injector. 

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10 minutes ago, Murray_Calavera said:

You realise that the majority of the time the injector is firing, it's spraying onto the back of a closed valve right? 

Are you trying to improve your emissions at idle?

I can guarantee that your transient response will not be improved by using a spilt spray injector. 

Its also spraying when there is a rush of cool boosted air coming in, so immediate atomisation and swirl dispersal. 

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19 minutes ago, tridentt150v said:

Its also spraying when there is a rush of cool boosted air coming in, so immediate atomisation and swirl dispersal. 

I find it strange that people get so caught up in these concepts. 

When we think about the real world drivability and performance of the car, are you trying to say that cars with single cone spray patterns do not atomise their fuel well and have drivability issues? 

Or are we trying to say something like, single cone spray pattern injectors are 99.1% perfect and by going to split spray it's improved to 99.2%? (numbers made up to express an idea, not to put a value on how effective either setup is)

Other things to think about, OEM's care a lot about emissions etc, yet how many cars end up with split spray injectors from the factory? 

Thinking about the other extreme side of things, how many big power 1000kw+ cars use a split spray injector? If there was performance to be gained here, why isn't the aftermarket developing large motorsport split spray injectors? 

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It's a port injected car, who gives a crap... as long as there's near equal fuel being dumped into each runner then happy days!

If we were talking about direct injected, then sure you want the spray pattern to be as optimised as possible but hey we are dealing with these rust bucket shit boxes.

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26 minutes ago, Murray_Calavera said:

I find it strange that people get so caught up in these concepts. 

When we think about the real world drivability and performance of the car, are you trying to say that cars with single cone spray patterns do not atomise their fuel well and have drivability issues? 

Or are we trying to say something like, single cone spray pattern injectors are 99.1% perfect and by going to split spray it's improved to 99.2%? (numbers made up to express an idea, not to put a value on how effective either setup is)

Other things to think about, OEM's care a lot about emissions etc, yet how many cars end up with split spray injectors from the factory? 

Thinking about the other extreme side of things, how many big power 1000kw+ cars use a split spray injector? If there was performance to be gained here, why isn't the aftermarket developing large motorsport split spray injectors? 

There’s no real power benefit to better targeted spray. That’s not at all what I was claiming. I just want to see if I can improve the transient response in high delta throttle situations relative to the factory injectors. The 040 injectors will do better than factory purely by virtue of their much smaller droplet sizes but spray targeting helps too. The other aspect is emissions. Part of that comes from just naturally better AFR control in transients from less wall wetting but also during cold starts I would expect to be able to pull out some enrichment. Not a ton but some. Almost all of this is only relevant for low RPM where open valve injection is doable. 

As for whether OEMs use dual spray in PFI it was very popular starting with EV6 generation injectors and was refined further with the EV14s.

1 hour ago, tridentt150v said:

Its also spraying when there is a rush of cool boosted air coming in, so immediate atomisation and swirl dispersal. 

I wasn't going mention this because I'm not trying to start internet arguments, but in the spirit of keeping SAU as a source of truth - 

This isn't really what happens, in the scenario of a large change in throttle opening, the change in pressure causes the fuel to be forced onto the fuel film on the port wall causing the fuel film to grow momentarily. This causes the car to momentarily lean out. This is why transient throttle enrichment exists to inject extra fuel so the car doesn't lean out on tip in.

Single or split spray pattern doesn't matter because it's the pressure change that is forcing the fuel onto the port wall/fuel film.

If your curious about it, you can look at Motec M1 training material as that series of ECU allow for fuel film modelling.

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1 hour ago, joshuaho96 said:

There’s no real power benefit to better targeted spray. That’s not at all what I was claiming. I just want to see if I can improve the transient response in high delta throttle situations relative to the factory injectors. The 040 injectors will do better than factory purely by virtue of their much smaller droplet sizes but spray targeting helps too. The other aspect is emissions. Part of that comes from just naturally better AFR control in transients from less wall wetting but also during cold starts I would expect to be able to pull out some enrichment. Not a ton but some. Almost all of this is only relevant for low RPM where open valve injection is doable. 

As for whether OEMs use dual spray in PFI it was very popular starting with EV6 generation injectors and was refined further with the EV14s.

Can you expand on 'improve transient response'? When you say this, I have a feeling I'm not picturing the same thing you are.

Could you explain from a driving experience, what it is the car is doing that you don't like and what you are hoping the car will do after it has had it's 'transient response' improved? 

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20 minutes ago, Murray_Calavera said:

Can you expand on 'improve transient response'? When you say this, I have a feeling I'm not picturing the same thing you are.

Could you explain from a driving experience, what it is the car is doing that you don't like and what you are hoping the car will do after it has had it's 'transient response' improved? 

I don’t even know if things will improve but the hope is when snapping the throttle open it’ll respond better in that initial instant and require less transient enrichment. Some things are only going to be noticeable in ECU logging or staring at a five gas analyzer. Andy now at Haltech mentioned offhand in a video once that when tuning x-tau stock injectors often have far lower X constants compared to aftermarket decapped injectors.

2 minutes ago, joshuaho96 said:

I don’t even know if things will improve but the hope is when snapping the throttle open it’ll respond better in that initial instant and require less transient enrichment. Some things are only going to be noticeable in ECU logging or staring at a five gas analyzer. Andy now at Haltech mentioned offhand in a video once that when tuning x-tau stock injectors often have far lower X constants compared to aftermarket decapped injectors.

Ok cool, I think we are on the same page. 

Just by chance, at the moment I've currently got all transient throttle enrichment turned off in my R33. There has been zero change to the cars driving behaviour. The only reminder that I have that AE is turned off, is on tip in, for about 0.1 seconds my mixture leans out and it's not even much of a lean out, we are talking like 14.7 to 16.5ish. 

Personally I only really care about performance and how the car drives. If there is zero discernible change in driving behaviour or performance, I really don't have a lot of interest in spending time / money in that area. 

Totally cool for you to want to hit whatever numbers you want to hit in your logged data though, horses for courses and all that.  

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23 minutes ago, Murray_Calavera said:

Ok cool, I think we are on the same page. 

Just by chance, at the moment I've currently got all transient throttle enrichment turned off in my R33. There has been zero change to the cars driving behaviour. The only reminder that I have that AE is turned off, is on tip in, for about 0.1 seconds my mixture leans out and it's not even much of a lean out, we are talking like 14.7 to 16.5ish. 

Personally I only really care about performance and how the car drives. If there is zero discernible change in driving behaviour or performance, I really don't have a lot of interest in spending time / money in that area. 

Totally cool for you to want to hit whatever numbers you want to hit in your logged data though, horses for courses and all that.  

Yeah I think it’s fair to say my goals are a little weird compared to most that modify their car. I still debate semi-frequently whether it’s worth it to try and do water injection to see if I can run lambda 1 deep into boost. 

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