Installation guide for the VTT Double Shotgun dual hpfp fueling kit
Intro
Please note, there is not a quick or fast way to do this modification. It is done in a low visibility area, the hardest parts of the job are not only hard to access but they aren’t very visible. You'll have to spend some time trying to figure out how to proceed with some steps because there are several variables ranging from vehicle and chassis manufacturing variances, hardline orientation, personal preferences and individual modifications. The clearances are very tight and there just isn’t much room. Be prepared to take more than one day to do this in case something comes up. Borrowing a lift with a deadline may not be the best idea because this takes time. With this guide, getting it knocked out in half a day might be possible. Hopefully this compilation of tips and additional photos this guide provides can help you cut down the time myself and others spent scratching our heads and struggling. There have been several people who have given tips and input who deserve credit including @longnvu @Shane303 @Chris@VargasTurboTech @Turby @martymil @Edson and probably others I missed.
There are a couple of optional jobs you can do at the same time as the shotgun install. The new serpentine belt pullies of course, as well as an aluminum power steering pulley and the billet coolant flange that goes into the head. I highly recommend doing all of these things as you’ll be staring them all right in the face and you can’t get any closer to them. The aluminum power steering pulley is entirely optional, but it is a little bit of insurance for the pulley cracking from hitting your subframe, causing the serpentine belt to get sucked into your front main seal(EDIT: This is do at your own risk, if the pulley doesn't break the next weakest thing will which is unlikely to be preferable). This pulley and a pair of upgraded motor mounts should all but prevent that one scenario from happening. The tensioner and idler pullies are obvious replacement items depending on how many miles they have on them, and the billet mickey mouse shaped coolant flange is another preventative item you should consider since that piece tends to corrode over time and break down.
When you buy the tensioner pulley specifically, make sure you buy a high quality pulley because some of the aftermarket pullies are made of a weaker metal and the T60 will strip out when you try to put the belt on. If you do intend on installing the aluminum power steering pump pulley, I recommend loosening those bolts before you remove the serpentine belt. If you try to do it when the belt is off,the pulley will spin freely when trying to loosen the bolts on it and can make it a bit more annoying.
When doing this installation, I decided to change the way the heater core return lines were ran, so I needed to buy some 3/4" heater hose and straight barb fitting and three clamps. You don't have to do this, but feel free to check out how I did it.
Also my fuel feed line Y hose was too short on one leg, so I needed to extend it a couple inches so that it would fit properly. If you're going to be on the clock, it might be helpful to go buy 6-7 inches of 3/8 fuel hose and some crimp clamps.
To get started with the install, remove the charge pipe, intake manifold, radiator fan, drain the coolant and remove the serpentine belt using the normal procedures making sure to take photos of your belt so you know how to put the new one back on. I also recommend pulling the intercooler as it can free up quite a bit of space and make things a lot easier, and is required for some brands due to clearance reasons.
Heater Core Coolant Return Pipe Modification
The first thing you have to do is modify the heater core return pipe which leads to the thermostat and coolant expansion tank on one end and plugs into the heater core through the firewall on the other. You can follow the original instructions and parts or you can make your own coolant line, both will be explained.
The kit comes with a bit of 90 degree plumbing which is a combination of 1" and 3/4" hose and adaptors. Coming from the thermostat/expansion tank, the instructions tell you to cut the plastic pipe right before the heat exchanger for those with automatics, after the pipe flares back out. For manual cars, coming from the same direction, after the first mounting bracket the pipe diameter reduces, then flares back out again, this is the same place.
If you have an automatic, you have to cut the hose leading to the heat exchanger after the diameter necks down so that it will fit on the T that is provided. But after some analysis, it may be better to cut after the T for the heat exchanger depending on the space in your particular car and how you want to secure this hose to the car. This retains the factory quick connects and hoses and the T fittings are no longer needed.
Here is the Automatic pipe, the blue line is where the instructions tell you to cut, the red line is approximately where I suggest you cut:
For those who are manual, here is the 6MT heater core pipe, this one is much more straight forward:
You may have to cut in a slightly different spots than those shown above, depending if your hose will fit on the end. Keep in mind the pipe diameters change, so you may end up using some of the adapters that come with the kit to make this work. Now continue to follow the instructions to complete the original coolant pipe modification.
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Another other way to go about this if you are manual transmission or have an aftermarket automatic transmission cooler, is to buy a 5 foot length of Vibrant 20455 heater hose and a 3/4" straight barb fitting. Making sure the coolant has already been drained, use some needle nose vice grips or channel locks and pinch the clamp connecting the rubber hose from the thermostat to the plastic heater pipe and slide it toward the plastic side to relieve the pressure from the hose.
Make sure you have a bucket handy because there is probably some left over coolant still stuck in this pipe. Leave the bucket there, because periodically coolant would randomly come out of the engine, even hours later. Grab a screw driver and gently go around the hose and try and brake whatever mechanical seal may be there, and pull the hose off the pipe. It would help if you pinched the line with a clamp of some kind so you don't have coolant pouring out from both ends.
Now follow this hose you've disconnected back toward the driver side and up to the fire wall. Remove the clip and pull the hose off. You should be able to lift up on this hose once it is free from all the other wires and things, and the plastic portion of the heater pipe should be angled enough to come out of the bottom.
Now hook up your heater hose to the firewall using a new clamp and run the hose straight down to the ground being sure to stay clear of the steering column.
From here there are a couple ways you can route the hose depending on your preference and turbo configuration. I am single turbo and chose to route the hose around the back of the oil pan and up to the front coming out right by the water pump.
You may find that the hose coming from the thermostat is too wide for the 3/4" straight barb, feel free to cut the flared portion of hose so the fit is more snug.
Use some clamps, preferably crimp clamps to secure these lines in a permanent fashion and use zip ties to make sure the hose is secure along the route you chose.
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