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Bosch Uprated Injectors

Messages
14
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16
Location
Los Angeles, CA, USA
Update for everyone waiting. Tuner says so far so good.

I've also been looking at the fuel rail pressure and it will read almost to 3000 psi. I do not know much about fuel systems or tuning but hopefully that bit of information helps someone who does know
I believe I read frp should always be above 2000 psi so 3000 gets a thumbs up from me dawg
 


Messages
219
Likes
289
Location
Kalamazoo, MI, USA
Vdyno is assumed to be simulating a Dyno so it would be a wheel hp number. If you post the log I can throw it in vdyno and spit out a graph. I'd like to see the fuel pressures myself. I'm almost ready to make a jump to buy and install myself with the good news.
 


Messages
6
Likes
6
Location
Summerville, SC, USA
I'm not hearing that there's a difference between this and the OE. The results all sound OE-ish.
It's possible that the only difference is orientation of the hpfp of ours and the jag, and that the only real difference is the injectors size and fuel flow which has been proven earlier in this thread. If the 320hp is the max on the jag hpfp then it's likely the only change was the orientation but good info to pick up on.
Vdyno is assumed to be simulating a Dyno so it would be a wheel hp number. If you post the log I can throw it in vdyno and spit out a graph. I'd like to see the fuel pressures myself. I'm almost ready to make a jump to buy and install myself with the good news.
I'm ready to buy too, provided it makes more than the 320hp on E30. Hopeful to see what the results are on a good run for Raz
 


Messages
51
Likes
108
Location
Lake City, MI, USA
It's possible that the only difference is orientation of the hpfp of ours and the jag, and that the only real difference is the injectors size and fuel flow which has been proven earlier in this thread. If the 320hp is the max on the jag hpfp then it's likely the only change was the orientation but good info to pick up on.
If that's the case that'd be really disappointing.. not much purpose in replacing our non-problematic HPFP's with ones that require modification to get them fitted and offer no performance overhead :(
 


Messages
301
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344
Location
Pharr, TX, USA
I'm not sure what to make of it, my tuner is saying that the tmap and map sensors are maxed out. Would this cause my HPFP to drop pressure? If I upgrade my sensors would that help the HPFP? My data shows it will spike to almost 3k psi on FRP but it's only when I go wot. Then it continues to drop pressure as RPMs climb... I would like for this jag HPFP to work but it looks like it is dependent on the cam lobe. How does the Xtreme xdi HPFP work without changing the cam? Something is missing from the equation because my car feels like it wants to go faster but it doesn't.

Any input or information is appreciated.
 


its_stock

Member
U.S. Air Force Veteran
Messages
120
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150
Location
Tokyo, Japan
How does the Xtreme xdi HPFP work without changing the cam? Something is missing from the equation
Most OEM fuel pumps use the same piston inside, so that's the bore of the fuel pump and then your cam lobe profile affects the stroke. The xdi pump uses a larger piston and the same stroke that's how it is able to pump more fuel than the stock fuel pump. If you do research into the Audi fuel pumps or the VW fuel pumps those guys buy a rebuild kit that puts a larger diameter piston in the pump to increase fuel flow.
 


TyphoonFiST

9000 Post Club
Premium Account
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Rich-fizzield
Most OEM fuel pumps use the same piston inside, so that's the bore of the fuel pump and then your cam lobe profile affects the stroke. The xdi pump uses a larger piston and the same stroke that's how it is able to pump more fuel than the stock fuel pump. If you do research into the Audi fuel pumps or the VW fuel pumps those guys buy a rebuild kit that puts a larger diameter piston in the pump to increase fuel flow.
Couldn't there maybe be a different size cam bucket slightly taller or smaller to effect the stroke to pump more? [emoji848]

Sent from my SM-S908U1 using Tapatalk
 




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