helix overdrive or vtt single barrell

foe516

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Nov 5, 2016
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so i am in the middlle of installing a set of hydra 650's and am thinking about fueling. i currently have a stage 2 bucketed lpfp and the original fuel it TBI. i could probaby hit 500 whp on straight e85 and more on say e50. with the sales going on this weekend it got me thinking of either the helix 3x or the vtt single shotgun. what are everyones thoughts?
thanks
 

martymil

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Sep 6, 2017
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There is a number of articles on these overdrive kits.

I'm not going to talk about it as it going to turn into a helix vs shotgun shit show.

Run a search and make up your own mind.
 
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gmagnus7

Corporal
Dec 3, 2018
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I believe both have the same overdrive amount (with the normal helix), and with the new HPFP tables they should support similar amounts of power. Shotgun is relocated and belt driven thus powered by the crank so it may put some further strain on the crank hub. Probably not enough to do anything but still. Helix is vacuum pump/chain driven so it might put more strain on the actual chain itself and vacuum pump (which feeds the brake booster). I don't have either so not an expert.
 

Traf

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Aug 3, 2017
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Both do the same thing, one is much easier to install than the other and requier no permanent modification to the vehicul.
I have the VTT shotgun on my car, but if i had to do it again, i would go Helix hands down.
 

martymil

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If you buy a shotgun this weekend you get 15% off in their store.

Both take around the same time to install and you get a new replacement engine belt which would be getting tired now on most cars.

Shotgun is a lot cheaper but a little more to install and a lot easier to replace the pump if it ever lets go as you dont have to tear the car apart
to get to the pump later.

these are the difference in install and price, do the research on the rest.
 

Traf

Sergeant
Aug 3, 2017
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Come on @Traf there is no permanent modifications on both kits, they are both fully bolt on.

Last time i checked i had to cut and reroute cooling hoses when installing the VTT.
Helix would be much much easier and faster to install.
 

martymil

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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
 

RNM

Corporal
Jun 3, 2019
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I have active steering on my car therefore the shotgun would not work on my car. The Helix overdrive has been working flawlessly (with the bracket and billet vacuum cover) on my vehicle for the past 3 months and just recently started running full e85 on upgraded turbos.
 

martymil

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Coming onto 3 years on the double barrel with no signs of failure.

The time factor is nothing its how the car is driven during that time and mine is not a.daily but a fun car when it is and its done over 20k miles or 30k km.

At the end of the day choose wisely, look at all the facts, threads and reviews and make an educated guess.

In the end of the day its your car and both have their pros and cons and if they fail you have to be ready to take the consequence of running a race only product on the street.

Its up to the individual to make that decision.
 

doublespaces

Administrator
Oct 18, 2016
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If you do the shotgun, have the install done professionally by someone with experience. That is what VTT recommends and it is recommended for good reason. If you want to DIY:
 

martymil

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If you do the shotgun, have the install done professionally by someone with experience. That is what VTT recommends and it is recommended for good reason. If you want to DIY:

An experienced mechanic that has done many of these can do it in 3 to 4 hrs taking it easy when he knows what he is doing.

If they haven't done one before allow a full day.
 
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martymil

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Only downside I have with the helix 3x is the chatter on startup.

The only downside ?

Its a race product not designed for street use, you cant say its the only down side just have to read the thread.

All race products carry a disclaimer, he needs to make that decision for himself
 

fmorelli

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@foe516 - my thoughts: I've been waiting and continue to wait.

@martymil is right you can do some research on the forums. Personally I've heard more privately from people that don't post, which makes me gunshy. I'm an active steering Z4. I was hoping Spool would take a serious design revision on the Helix, before I committed (they definitely seem to have the chops to do it). From what I've heard, I'm unconvinced brackets and billet vacuum plates address the inherent vibration issues.

Superb product packaging - I'd buy in a heartbeat if a redesign solved the issue at its core.

Filippo
 
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zomski101

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Dec 28, 2019
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The only downside ?

Its a race product not designed for street use, you cant say its the only down side just have to read the thread.

All race products carry a disclaimer, he needs to make that decision for himself
Yes, MY only downside with the helix 3x is the chatter on start up. OP is ask for thoughts/opinions.
Don't know what you're going about that race product mumbo jumbo.
 

martymil

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They are both race products and not mumbo jumbo, its up to the individual to choose.

If the product causes a failure and accident because you ran a race product on the street and it causes permanent disability or death your going to jail.

Mumbo jumbo lol.

That goes for all race products.
 

doublespaces

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There is a chatter fix, reduces the chatter to about 2-3 seconds. With voltage tweaks you could probably eliminate it entirely.
 
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