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Gavkat09

Member
Nthusiast
Aug 23, 2020
53
22
8
Sydney
Who’s upgraded or changed there HPFP? What one did you decide to use. When changing it did you replace any other parts or just the hpfp?
 
What do want to achieve with changing it?
I just had this discussion with the only (?) forum member wo did it and he (@TarmoT ) told me that it's not necessary below 420 PS. And if you want to go above that number you'll need lots of changes (turbo, intercooler, downpipe, valves etc. pp.).
 
I do know of one person in Australia that put one out of a tcr i30 in his car. No idea of part no or what he did
 
It should be a plug-n-play replacement when you don't want more power (standard OEM pump).

 
What do want to achieve with changing it?
I just had this discussion with the only (?) forum member wo did it and he (@TarmoT ) told me that it's not necessary below 420 PS. And if you want to go above that number you'll need lots of changes (turbo, intercooler, downpipe, valves etc. pp.).
Sorry but I have a different view on that. The hpfp is already struggling to deliver fuel on most Ns (its a bit of a diva) when you are running 350ps. So I consider it a mandatory upgrade when changing the turbo, too
 
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Sorry but I have a different view on that. The hpfp is already struggling to deliver fuel on most Ns (its a bit of a diva) when you are running 350ps. So I consider it a mandatory upgrade when changing the turbo, too
You don't have to be sorry 😉.
Tbh I don't have a proven point yet. Atm I can only rely on opinions of people who already did go beyond 350+ PS.
Do you have anything to read / links whatsoever, @Bu11eT ?
 
You don't have to be sorry 😉.
Tbh I don't have a proven point yet. Atm I can only rely on opinions of people who already did go beyond 350+ PS.
Do you have anything to read / links whatsoever, @Bu11eT ?

sadly not. If you know Markus from MT Tuning Solutions aka Turbotrucki (the guy who tuning the i30N TCR from JP Performance), he's the guy who actually says so. IIRC he measured multiple Ns and most of them had issues with the fuel pressure coming from the HPFP. If you are interested in that topic, just hit him up on Insta, he's quite a chatty guy :)

He does lots of measurements and tries to learn as much as possible about the car (particularly the ECU) and that was one of the findings he had. At least that was my understanding of the topic.

He did the software on quite a few i30Ns already, including a few ones which run 400+ps.
 
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The OEM high pressure fuel pump found on the Veloster N doesn't sustain fuel pressure at high engine loads, an
issue which is apparent with upgraded turbochargers;
GraphSet-2k__96683.1607549017.jpg

However as soon as they come available again, I'll be adding one with the OEM Turbocharger.
 
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Also, to provide a few more insights:
The lacking fuel pressure will not show itself on a dyno, as on a dyno run you are not changing gears while accelerating hardly.

Why is this an issue?
When changing gear, the HPFP will not provide any fuel as it's supposed to, but as you are getting a torque-peak when changing gears, the HPFP now has to deliver nearly full pressure in a very short timeframe. Under bad circumstances, this can result in engine misfires.

The HPFP issue can show itself from 320bhp onwards already.

Stock pressure: 200 bar
Pressure from 320bhp onwards under load with full boost: ~180 bar
And then you shift from 4th to 5th under load. Pressure is now: as low as ~100 bar

This is just one example.