DIY VTT Double Shotgun Installation

martymil

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As im not running pi i had to to improvise

But as long as the damper is between the sensor and both di pumps it should work

Really sore back atm waiting to get the car on the hoist in the next few days
 

doublespaces

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Oct 18, 2016
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As im not running pi i had to to improvise

But as long as the damper is between the sensor and both di pumps it should work

Really sore back atm waiting to get the car on the hoist in the next few days

I wonder if a fitting could be made to stick it where the HPFP sensor is, kind of a T of some sort? Or is that too close to the sensor?

But if I'm understanding this right, it works on both the high and low pressure sides?
 

martymil

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Not sure that will work, I moved my sensor away from the pumps and put it next to the filter and ethanol sensor under the car, this has greatly reduced the oscillations but still there, next step is to put the dampener between the pumps and the lpfp sensor, ill take a pic when its done.
 

martymil

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Something like this 15246334239379114967177353726051.jpg
 

Erichale77

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I think the oscillations are caused by the pressure changes in the rail(s). These can be used in either high or low side fuel rails. I considered using one in my PI rail and HPF rail. Curious to see how it works for you in the location you selected.
 

martymil

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This dampener cannot be used on a hpfp rail its only for port injection rail on the lpfp side

From what i was told these where designed to dampen pressure changes that are caused by large injectors opening and closing rapidly and taking huge volume of fuel causing spikes in the pressures or in our case the di pumps are like these injectors hence why im trying this

Im not saying it will work but if it dampens the spikes even by 50 % it will be worth it

Anyone here run a return line and using an fpr ?

Do you get these oscillations as this will be my next step if this doesnt work .
 

Erichale77

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I run a return line from my PI rail and have a fpr but i'm only running one HPFP at the moment and I dont notice any oscillations yet
 

martymil

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Yeah these oscillations mainly happen with double barrels when you target 3000 psi plus

Anyone out there with a double barrel and a return line ?
 

amik

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Apr 8, 2018
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I’ll have mine set up with a return line soon. Have all the parts in hand. Hope to install it this weekend.
 

amik

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Apr 8, 2018
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Nice. Seems to do the trick on the LP side. Not sure if the HP rail fluctuations are of any concern as I’ve got the same.

Mind sharing the details and/or part numbers of the different fittings/parts in that photo? Fuel filter, Tee for the sensor, damper and Y fitting for the split to the HPFPs.
 

doublespaces

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Before

View attachment 10944

After

View attachment 10945

Well it works guys, not bad and cheap

Guess its not perfect but it will do

Need to get it on a dyno to fully load it up

View attachment 10946

This thing only comes in 8 ORB or 3/8 NPT which lends itself to 8AN hoses, but I think a lot of us have 6AN lines. I wonder what would happen if you ran two of these? Also, since our fuel pressure is static targeting 72 psi, we don't need the boost reference connected, right?
 

martymil

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I wasn't sure if the 6an inline was going to affect flow and volume so i brought the 3/8 version and used a 3/8 npt tee block and converted it back to 6an inlet and 8an outlet to maximize the flow

This was an experiment so its not the ideal setup

If i was to do it again i would get the 8an in line version and convert one side back to 6an and the otherside would connect straight up to the ypiece

Every setup is different but every part can be found in the speedflow catalog and the dampener is from radium as mentioned before
 

doublespaces

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I wasn't sure if the 6an inline was going to affect flow and volume so i brought the 3/8 version and used a 3/8 npt tee block and converted it back to 6an inlet and 8an outlet to maximize the flow

This was an experiment so its not the ideal setup

If i was to do it again i would get the 8an in line version and convert one side back to 6an and the otherside would connect straight up to the ypiece

Every setup is different but every part can be found in the speedflow catalog and the dampener is from radium as mentioned before

So what do you think about running two of these things back to back, would that somehow double the cushion/damping effect?
 

doublespaces

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I cant see why not but ill put them both next to the pumps to maximize the dampening

You mean one on each Y hose leg? I would think before the split would be better since you have both damping all the time?