Supercharger or not?

[EricM]

I cobbled together a Roush system built around a take-off supercharger from a 1 season ski boat. Some of the parts were purchased new from Roush, except for the blower, injectors, fuel rails, some pulleys, etc. which were just lightly used. Bought quite a few new parts I needed on eBay cheap. I'm running a stock exhaust, stock oil pump gears, 75mm pulley. If you have a good tune (JDM) don't crush your throttle from stoplights or hammer on/off the throttle a lot when wheeling, you shouldn't have to worry about the oil pump gears unless you're making stupid power, which I'm not. So far so good.

I upgraded my transmission cooler recently, and also added water/methanol injection as a safeguard.

Installed at 60k miles, which was a few months ago. Love it so far. If you are good with wrenches, and patient, don't be afraid to do it yourself. My total cost was under $5k, including plugs, tune, etc.

So you bought the compressor/IC/lower manifold used from a boat? Ingenious.

Everything else is pretty easy once you have those parts.

 

[vegascarnut]

So you bought the compressor/IC/lower manifold used from a boat? Ingenious.

Everything else is pretty easy once you have those parts.

I did that exactly. I don't know about ingenious—I'm just REALLY cheap! It came with the injectors, fuel rails, idler pulley bracket, etc. It was off of one of the Indmar Raptor 575 engines. The wiring harnesses, CAI, throttle body, intercooler, etc. were purchased new from various sources.

 

[BoostedToy]

My truck is inching towards 125k miles, all with a Roush Stage II. Right around 100k miles, I moved to Alaska. 90 octane is premium which left me with a decision to make. De-tune the truck, which would leave with less than optimal timing advance and possibly pulley up for less boost. That didn’t sound like a good idea. Pivot to option two: Find some octane and perhaps even further dial in the tune.

I chose option two. After some research, JDM and VMP both seemed to have their tunes dialed in much better than Roush. The only reliability issues this truck had at that point was shearing off the belt tensioner on a 4wd HI 1-2 WOT shift. It was nearly a guarantee it would occur each time with that scenario. That got old quick, so I just avoided 4WD launches. That took some fun out of the truck. After some back and forth, I went with VMP for a tune and pulley down to 72mm (from 75mm). JDM would have been great too, but I previously worked with VMP on a supercharged Mustang.

I called around and researched octane products. The octane answer came from Boostane. Nearly 25k and it works like a champ and is very cost effective at the final octane I need (90 increased to 93). It costs around .16c/gallon. Well worth it. I’ve heard of potential to prematurely foul plugs, but it has yet to happen on mine and I pulled them once about 4K miles ago to check them out. They are a little orange (I believe MMT is the primary active component for the pre-ignition inhibition), but otherwise fine.

In summary, I have had two 2013 Raptors. One NA and this supercharged truck. If you have the means, there is no decision. Default to supercharged!

 

[EricM]

My truck is inching towards 125k miles, all with a Roush Stage II. Right around 100k miles, I moved to Alaska. 90 octane is premium which left me with a decision to make. De-tune the truck, which would leave with less than optimal timing advance and possibly pulley up for less boost. That didn’t sound like a good idea. Pivot to option two: Find some octane and perhaps even further dial in the tune.

I chose option two. After some research, JDM and VMP both seemed to have their tunes dialed in much better than Roush. The only reliability issues this truck had at that point was shearing off the belt tensioner on a 4wd HI 1-2 WOT shift. It was nearly a guarantee it would occur each time with that scenario. That got old quick, so I just avoided 4WD launches. That took some fun out of the truck. After some back and forth, I went with VMP for a tune and pulley down to 72mm (from 75mm). JDM would have been great too, but I previously worked with VMP on a supercharged Mustang.

I called around and researched octane products. The octane answer came from Boostane. Nearly 25k and it works like a champ and is very cost effective at the final octane I need (90 increased to 93). It costs around .16c/gallon. Well worth it. I’ve heard of potential to prematurely foul plugs, but it has yet to happen on mine and I pulled them once about 4K miles ago to check them out. They are a little orange (I believe MMT is the primary active component for the pre-ignition inhibition), but otherwise fine.

In summary, I have had two 2013 Raptors. One NA and this supercharged truck. If you have the means, there is no decision. Default to supercharged!

That octane booster is the same as Torco, et all. It does work, and yep it does leave the plugs orange.

You can buy better tenioners. These won't break. https://www.thumpracing.com/

Metco also sells braces for stock Ford tensioners.
https://www.metcomotorsports.com/proddetail.asp?prod=MTP0001-1
If they ones they make don't work with the F150 tensioner, they can probably make you a custom one for under $100. You could fab up something yourself pretty easy too. You can't see it in their pictures, but there is a tab of metal on the backside of the plate that extends under and supports the end of the arm.

 

[BoostedToy]

Thanks for sharing. Fortunately, the issue resolved with the tune.

 

[vegascarnut]

My truck is inching towards 125k miles, all with a Roush Stage II. Right around 100k miles, I moved to Alaska. 90 octane is premium which left me with a decision to make. De-tune the truck, which would leave with less than optimal timing advance and possibly pulley up for less boost. That didn’t sound like a good idea. Pivot to option two: Find some octane and perhaps even further dial in the tune.

I chose option two. After some research, JDM and VMP both seemed to have their tunes dialed in much better than Roush. The only reliability issues this truck had at that point was shearing off the belt tensioner on a 4wd HI 1-2 WOT shift. It was nearly a guarantee it would occur each time with that scenario. That got old quick, so I just avoided 4WD launches. That took some fun out of the truck. After some back and forth, I went with VMP for a tune and pulley down to 72mm (from 75mm). JDM would have been great too, but I previously worked with VMP on a supercharged Mustang.

I called around and researched octane products. The octane answer came from Boostane. Nearly 25k and it works like a champ and is very cost effective at the final octane I need (90 increased to 93). It costs around .16c/gallon. Well worth it. I’ve heard of potential to prematurely foul plugs, but it has yet to happen on mine and I pulled them once about 4K miles ago to check them out. They are a little orange (I believe MMT is the primary active component for the pre-ignition inhibition), but otherwise fine.

In summary, I have had two 2013 Raptors. One NA and this supercharged truck. If you have the means, there is no decision. Default to supercharged!

Here in Vegas, we only have 91, and the JDM tune I'm running does great with 91. Truck still makes plenty of power for sure. I've run 95 in it, and it feels stronger because it doesn't have to pull so much timing when it gets hot. I have a feeling you would be happy running a 90 Octane tune, and save a lot of money on octane booster. Just my opinion, of course.

 

[vegascarnut]

That octane booster is the same as Torco, et all. It does work, and yep it does leave the plugs orange.

You can buy better tenioners. These won't break. https://www.thumpracing.com/

Metco also sells braces for stock Ford tensioners.
https://www.metcomotorsports.com/proddetail.asp?prod=MTP0001-1
If they ones they make don't work with the F150 tensioner, they can probably make you a custom one for under $100. You could fab up something yourself pretty easy too. You can't see it in their pictures, but there is a tab of metal on the backside of the plate that extends under and supports the end of the arm.

Main issue with the tensioners (and belts) breaking on Roush blowers is the Roush tunes suck! Once you have a good tune in there, those issues are usually resolved.

 

[EricM]

OK, now I am genuinely curious as to how a tune can cause the belt tensioner to break. I didn't know this was a thing with S/C 6.2L engines. Is it in the firmness/speed of the transmission shifting?

I've seen it happen a lot on stick shift Mustangs with aggressive clutches and big blowers- but never on an automatic. With clutch dumps on upshifts and a real aggressive clutch, the change in speed for the rotors between shifts is really fast and all that energy needed to slow down the rotors for the next gear gets transferred into drive the belt and everything attached to it.

 

[vegascarnut]

OK, now I am genuinely curious as to how a tune can cause the belt tensioner to break. I didn't know this was a thing with S/C 6.2L engines. Is it in the firmness/speed of the transmission shifting?

I've seen it happen a lot on stick shift Mustangs with aggressive clutches and big blowers- but never on an automatic. With clutch dumps on upshifts and a real aggressive clutch, the change in speed for the rotors between shifts is really fast and all that energy needed to slow down the rotors for the next gear gets transferred into drive the belt and everything attached to it.

Exactly. It has to to with the transmission programming against various loads, shift points and firmness, etc. Now if you're running wicked amounts of boost then you're going to need more pressure on the belt, but most of the issues for your average customer seem to be resolved with a better tune.

 

[BoostedToy]

Here in Vegas, we only have 91, and the JDM tune I'm running does great with 91. Truck still makes plenty of power for sure. I've run 95 in it, and it feels stronger because it doesn't have to pull so much timing when it gets hot. I have a feeling you would be happy running a 90 Octane tune, and save a lot of money on octane booster. Just my opinion, of course.

Everyone has their own perspective. I appreciate that. I build in some margin of safety. If I purely use the paper blend requirements for 90 to 93, $300 gets me to 110 complete fills of a 34 gallon tank at .09c/gallon. Personally, I am willing and it makes sense to me to pay the slight premium. JDM was more optimistic on the loss than VMP. Either way, vs the Roush 93 tune, this allowed a little more boost (1.5psi-1.75psi), cleaned up the tune and all the while providing significantly improved non-load fuel consumption. Average mpg went from 11.3 over 3k summer month period to 15.1. That is a meaningful increase. It’s not a like vs like comparison though, as this is neat (no ethanol) fuel in Alaska. Still, E10 vs neat wouldn’t explain the full difference. When in Cincinnati two summers ago, I would achieve 14.2-14.5mpg at 70 mph. Post-tune on level highway, I am getting 18.8-19.0mpg.

There are other variables that have an effect, but on the macro, the tune certainly makes more power and consumes less fuel (even at WOT on the upper 1500rpm of the tune).


So for me, it’s probably closer to .12-15c/gallon. I also likely have 40-50fwhp on a 90 octane tune with the stock boost versus the additional timing afforded and mild boost increases.

I’ll pay for that. I’ll look forward to getting back to not messing with my routine of pouring 7-8oz of this additive with each full. It’s not too much of a hassle though.