helix overdrive or vtt single barrell


Aug 3, 2017
You don't have to cut it, you can replace the whole cooling hose which makes it reversible or just buy a new cooling hose that you cut.

It's not irreversible and not permanent
How can you claim both install take the same time then ? One is plug and play, the other you need to go under the car and cut cooling hoses and stuff...
I'm begining to doubt your objectivity...
Try to face the facts, Helix is a much more elegant and easier to install solution. Unless you are a VTT fanboy i see no reason to go with the single barrel.
Easier does not mean better, elgant we have very different views on what's elegant.

And yes around the same time or maybe around uo to 1hr longer pending on the mechanics experience with the kit.

Water line takes around 10 min to change and gets rid of the unreliable factory plastic pipe.

The whole setup is far more robust in the long run as proven, i have not seen one failure due to the design.


Aug 3, 2017
You like to have the final word don't you ?
Helix is much easier to install than Shotgun, should you change if you already have a single barrel? Fuck no thats stupid, both do the same thing, if single barrel works for you, don't change (my case)
What should you pick if you don't have any hpfp upgrade ? Helix...

Let's not hijack the thread any further.
  • 1Like
Reactions: miller335i


Jul 23, 2017
I run the VTT double barrel on my big single turbo. Has been a brilliant solution. I would much rather run off the belt than the flimsy vacuum pump and 'bracket fix'.

The Banshee

Nov 18, 2017
Lehigh Valley PA
N54 is still at port injection or nothing. That is the conclusion I came up with when researching this topic.

Some guys have sporadic success. Most of them are vendors or vendor associates. Many have issues with both options and don’t post.
  • 1Agree
Reactions: Torgus


Nov 5, 2016
thanks, the shotgun install does look a little intimidating. do you have to drill the fuel rail with the helix?

i think i will wait it out unless i change my Mind before midnight when the vtt sale ends, its $120 0ff and comes out to $680 shipped. my turbos are finally installed, just have to bleed the coolant and get an alignment. i haven't driven the car since march of 2019, might just push it with the TBI thats installed on the car and see where that lands me. i popped out the filter in the hpfp and changed the hardline when i did a walnut blast last year while the car was apart.
The shotgun install looks intimidating but really its easy.

Yes drilling the rail helps any di solution you choose with keeping the volume of fuel up to the injectors.

The fuel rail can empty faster than the pump can fill it due to the restriction in the rail.
Last edited:


Dec 3, 2018
Yea I think M18 had one option with a single piston type porsche pump to replace the N54 one entirely, and a second option to add an additional inline pump (N55 or whichever) to the existing pump.

Also XDI is finally working on a E85 rated HPFP for the N54, and also aftermarket piezo injectors too!

Who knows if either will work or how long it'll be before they release them.

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