Stock Fuel Rails, why they don’t keep up

[16GoManGoHC2]

Got some new rubber to try

 

[vortecd]

Got some new rubber to try
View attachment 99521

Are they cheaper then nittos?

 

[16GoManGoHC2]

Are they cheaper then nittos?

Only if you got them the way I did at about 295 a tire all in shipping and no tax. Their around 450 a tire cheapest I saw them

 

[16GoManGoHC2]

Are they cheaper then nittos?

Guy I got them from said he used to use Nitto NT05R and he said on the street these grip better and last 2-3 times as long. We shall see

 

[16GoManGoHC2]

Well made a WOT fuel trim change and got out one more time before the bad weather gets here. Seeing the most aircharge ever, it has to be coming from the Thitek porting, flirting with 2400 aircharge!! Once I get this belt slip under control I think it’s going to top 2400 in good air. Ran like a MONSTER!! Fuel still keeping up

 

[vortecd]

Since you are not running the grip tec pulley sand blast your pulley so it isn't smooth. I didn't have belt slip on my 2.4 with a 2.65 grip tec. Grip tec may even be able to coat your own pulley

 

[16GoManGoHC2]

Since you are not running the grip tec pulley sand blast your pulley so it isn't smooth. I didn't have belt slip on my 2.4 with a 2.65 grip tec. Grip tec may even be able to coat your own pulley

I’m running a 3.00 Griptec now, belt is a hair too long. I modified my AA detention or today. Hopefully I can get it to work and then the longer belt will be perfect and I’ll get more wrap on the pulley and no slip

 

[vortecd]

I’m running a 3.00 Griptec now, belt is a hair too long. I modified my AA detention or today. Hopefully I can get it to work and then the longer belt will be perfect and I’ll get more wrap on the pulley and no slip

I have a 3.00 with no slip. I also run the standard black gates belt

 

[jonx96]

Well made a WOT fuel trim change and got out one more time before the bad weather gets here. Seeing the most aircharge ever, it has to be coming from the Thitek porting, flirting with 2400 aircharge!! Once I get this belt slip under control I think it’s going to top 2400 in good air. Ran like a MONSTER!! Fuel still keeping up

View attachment 99527
View attachment 99528

Cant really tell if your pump is keeping up at 4000 rpm. You really need to get a good load behind it
The one at 6k is showing pressure fine but injectors are adding a ton which makes me think they arent getting the pressure they need.
Should not be a 25 percent difference in injectors from your 2.4 to the whipple.

 

[16GoManGoHC2]

I have a 3.00 with no slip. I also run the standard black gates belt

You spinning it with a stock lower or larger lower?

 

[vortecd]

You spinning it with a stock lower or larger lower?

stock lower and I know you have a bigger one. Just thinking right belt it should be fine

 

[16GoManGoHC2]

Cant really tell if your pump is keeping up at 4000 rpm. You really need to get a good load behind it
The one at 6k is showing pressure fine but injectors are adding a ton which makes me think they arent getting the pressure they need.
Should not be a 25 percent difference in injectors from your 2.4 to the whipple.

I took fuel away from WOT when I went to the 2.4 and the RE fuel rails. I thought between less boost and maybe better fuel flow but I’m thinking something else now after seeing what occurred going back to my HC rails and the Whipple on the ported heads. Airflow is up a bunch in the low end, would be up top too if it were not for belt slip. What I’m thinking is with the RE rails fuel pressure was up not down as injector DC was down not up as it would be if fuel pressure was really lower. I’m still around 50% DC now at 73 psi, was 45 inj DC with the 2.4. Look back at post 1323 and1333. If my fuel pressure was really 58 psi my injector DC would have been much higher then 48% at 4700 and 55 % at 6800. I’m expecting to see my inj DC about 65% at 6800 now with the Whipple once I get the tensioner in the right spot as now it’s almost on the loose side stop shut off and get back to 23-24 psi of boost up in the 6000 rpm range, and not expecting to see fuel pressure at 58 psi either, 68 maybe but I’m thinking still 70 or better. What do I think is going on between the RE fuel rails and the HC fuel rails? A scaling issue on the fuel pressure sensor output, just like HC uses 2 bar map sensors and the RE uses 3 bars sensors and one has to rescale the sensor data to be correct, I think the fuel pressure sensor is 8-9 bar per 5 volts and the HC is less, like maybe 6-7 bar and the RE rails at 70 psi actual is reading 58. I have both sensors I just need the time to make up a pressure rig to log the voltage output of each at different pressures like 50/60/70/80/100 etc. Remember, the RE stock tune runs at what 105 psi fuel pressure, and the HC what 84? I bet the RE sensor is scaled differently. Yes, it has the same plug as HC sensor but do do the map sensors and they differ in scaling. I should be running out of pump more so now then before and I’m not, all be it boost is down atm but 4500 rpm Aircharge is way up now and the pump DC has room to go yet at the same commanded figure as running the RE rails and the fuel pressure was down to 60 psi already, I think it really was 80+ as pump was at 89% DC, ie full bore to where it really only needed 75/80% to get 73 psi commanded, it’s why injector DC % was down to 40-45% then and why now at a real 73% I’m having to put the fuel back in because it’s not 80+ psi at the injectors any more but reading 58. Follow the hypotheses I’m getting at? Maybe it’s why everyone who went to RE rails on a HC platform think their pumps aren’t keeping up. They really are but the different sensor calibration is saying different.

 

[jonx96]

only way to take know I’d going to injector duty cycle. I agree weird calculations going on.
your 1700s are plenty big and luckily you have some heat room for error may not be a bad idea to start logging each injector individually

 

[Speedy!]

@16GoManGoHC2 your theory makes sense to me actually. Maybe @Jon-MooredPerformanceLLC can ping HPT about this and see if there is some fuel pressure sensor scale table that needs to be added as I've not found anything available for that.

We could also put a legit gauge on the fuel rail and measure actual fuel pressure vs what the logs show to know what's what. Might have to do it on the dyno or use a camera to record it at WOT though.

Even with the triple hat with 3 TI285 pumps my car showed a drop to 73 or 74psi fuel pressure at the track this weekend with commanded 80psi in the tune. Inj DC was like 65% and PW like 11 so I had no fueling issues. FPDC was also 89% so I bet it's something to do with that sensor's scale.

 

[16GoManGoHC2]

Hopefully my AAD Idler pulley mount modification works and I get it mounted tonight, get some more wrap on the pulley and tension on the belt and get some high rpm fueling and pump data soon.
The RE fuel sensor I can make a jig to test it pretty easily but the HC one being it’s part of the rail is going to be a bit more of a challenge without ruining a rail to cut one out of. And he want to have a donor HC DS rail they want to sacrifice to this experiment? I need the fuel pressure sender from one.

 

[16GoManGoHC2]

@16GoManGoHC2 your theory makes sense to me actually. Maybe @Jon-MooredPerformanceLLC can ping HPT about this and see if there is some fuel pressure sensor scale table that needs to be added as I've not found anything available for that.

We could also put a legit gauge on the fuel rail and measure actual fuel pressure vs what the logs show to know what's what. Might have to do it on the dyno or use a camera to record it at WOT though.

Even with the triple hat with 3 TI285 pumps my car showed a drop to 73 or 74psi fuel pressure at the track this weekend with commanded 80psi in the tune. Inj DC was like 65% and PW like 11 so I had no fueling issues. FPDC was also 89% so I bet it's something to do with that sensor's scale.

What size injectors? I bet your fuel pressure was really higher then displayed and the PCM thinks it is.

 

[vortecd]

You could also go with a stiffer tensioner. Jon's car has one and doesn't have belt slip with the smooth 2.85 pulley and 10% lower

 

[covidcommander]

Hopefully my AAD Idler pulley mount modification works and I get it mounted tonight, get some more wrap on the pulley and tension on the belt and get some high rpm fueling and pump data soon.
The RE fuel sensor I can make a jig to test it pretty easily but the HC one being it’s part of the rail is going to be a bit more of a challenge without ruining a rail to cut one out of. And he want to have a donor HC DS rail they want to sacrifice to this experiment? I need the fuel pressure sender from one.

Didn't know they were different... maybe post some pics if you can of the difference

 

[Unholy707]

I took fuel away from WOT when I went to the 2.4 and the RE fuel rails. I thought between less boost and maybe better fuel flow but I’m thinking something else now after seeing what occurred going back to my HC rails and the Whipple on the ported heads. Airflow is up a bunch in the low end, would be up top too if it were not for belt slip. What I’m thinking is with the RE rails fuel pressure was up not down as injector DC was down not up as it would be if fuel pressure was really lower. I’m still around 50% DC now at 73 psi, was 45 inj DC with the 2.4. Look back at post 1323 and1333. If my fuel pressure was really 58 psi my injector DC would have been much higher then 48% at 4700 and 55 % at 6800. I’m expecting to see my inj DC about 65% at 6800 now with the Whipple once I get the tensioner in the right spot as now it’s almost on the loose side stop shut off and get back to 23-24 psi of boost up in the 6000 rpm range, and not expecting to see fuel pressure at 58 psi either, 68 maybe but I’m thinking still 70 or better. What do I think is going on between the RE fuel rails and the HC fuel rails? A scaling issue on the fuel pressure sensor output, just like HC uses 2 bar map sensors and the RE uses 3 bars sensors and one has to rescale the sensor data to be correct, I think the fuel pressure sensor is 8-9 bar per 5 volts and the HC is less, like maybe 6-7 bar and the RE rails at 70 psi actual is reading 58. I have both sensors I just need the time to make up a pressure rig to log the voltage output of each at different pressures like 50/60/70/80/100 etc. Remember, the RE stock tune runs at what 105 psi fuel pressure, and the HC what 84? I bet the RE sensor is scaled differently. Yes, it has the same plug as HC sensor but do do the map sensors and they differ in scaling. I should be running out of pump more so now then before and I’m not, all be it boost is down atm but 4500 rpm Aircharge is way up now and the pump DC has room to go yet at the same commanded figure as running the RE rails and the fuel pressure was down to 60 psi already, I think it really was 80+ as pump was at 89% DC, ie full bore to where it really only needed 75/80% to get 73 psi commanded, it’s why injector DC % was down to 40-45% then and why now at a real 73% I’m having to put the fuel back in because it’s not 80+ psi at the injectors any more but reading 58. Follow the hypotheses I’m getting at? Maybe it’s why everyone who went to RE rails on a HC platform think their pumps aren’t keeping up. They really are but the different sensor calibration is saying different.

100% Mike I was talking to Speedy about this a while ago, I also have the Redeye fuel rails and sensor and finally got data with the setup. My IDC is way lower but my fuel pressure appears lower, which is contridictive. I believe it to be a scaling difference in the Redeye fuel sensor, only way to confirm is to get a mechanical gauge in the schrader valve when on the dyno I’m thinking

 

[Unholy707]

i topped 56% IDC with a 2.69 upper on e85 with 1300x2s and twin TI pump, same thing fuel pressure in the upper 70s. The Redeye fuel rails are way less restrictive because the sensor is no longer in line and on its own T, guarantee it’s a scaling/voltage difference.