Hi there,

well it looks like Troyer forgot to tell me something super important that actually was limiting my Roush blower to go past 6PSI!

I'd like to thanks Jim @ JDM for their support, they told me how to do the upcoming operation after having sent their custom tune.

So if you have Roush Supercharger, did you know that it comes with a box, a controller that dump boost once it reach 6PSI!?

Troyer gave me a custom tune claiming that it would make 8-9 PSI, I've never felt the wow factor and my dyno sessions were always in the 320HP - 450RHWP.

Yesterday I did the JDM process (super easy, took me 1min and I'm a noob) and now the truck is a lot faster!
I didn't flash the JDM tune yet because I need to install their 4lbs crank pulley but the truck is noticeably faster and more responsive!

A friend of mine told me that I should get a boost gauge because since the Roush controller is disabled the PSI could go crazy and could blow the engine

Thoughts?

Just bypass the Roush controller and now there isn't any 6PSI limit anymore!!!
You guys have no idea how happy I am now!

instructions from JDM:

 

I did the same thing as per JDM. I have a 4 lb lower and a 3.1 upper. Mine should make about 9-10 PSI but I have the boost gauge hooked up to a small outlet behind the motor and I'm fairly certain I am not getting an accurate boost reading.

Does anyone have a great picture of your boost gauge port that you hook your hose to on your motor?? I would love to change my location.

I am looking for 2004-2008 5.4 pics

 

The boost is controlled via the 'Charge Motion Controller' this is why you need to junk the Roush tune.

My boost gauge sender (AEM) is tapped into the blank port for the FRPS line. Only around 3-4 inches of vac line.

Will snap a pic if I get a chance.

 

Well it's more of a vac cap fitted to the Roush supplied boost / Vac line that connects to the FRPS.

Pretty straight forward set up.

 

widj, Just curious, how would this bypass affect a stock pulley system.

 

Is that with a stock size pulley or a smaller (2.8)?

What is his website?

 

I have a 2.8 supercharger pulley (upper) and not yet installed but soon 4lbs crank pulley

 

From what I've read the 2.8 should put you at 9-10 lbs. Do you have a built block? I am not sure a stock block will handle 14lbs.

 

no built block, really stock engine, well I hope that it will be fine, according to Jim..
Troyer told me that I should get without the crank pulley around 9PSI
Jim said around 8PSI, so with this crank pulley around 12PSI

Jim told me that he would have not recommended me the crank pulley if I didn't have LT headers as he said that LT headers help "reducing" the PSI at the engine, since it makes the engine more efficient, so this is safer

Secret there seems to be having a good exhaust flow..

but I'll still be slower than Jason and his 475RWHP that I see everyday in his sig (*sigh* *frustrated*)

 

12 lbs is a lot for a stock motor, but glad to hear you found out the little "secret!"

 

Seriously? This mod has been around since day one. I did the dump valve mod on my 2001 Lightning the day I purchased it new in 2001...I guess most of us old guys from that time are not here anymore and it never gets discussed. I know some that simply unplugged it...
On a side not, I saw as much at 14# of boost back in the day with a 6# lower and 2# upper.

 

I'm glad to hear that you knew about that

I went with Troyer because I'm new to tuning (Troyer is a self-proclaimed world's best F150 tuner) and he didn't know about this valve.

I thought I could share this info with people that don't know about this mod, regardless the tune you could get or mods, as long as you don't bypass this valve you will be stuck under 6PSI with a Roush blower

 

 

WHAT THE HELL! Just did this and noticed a difference for sure. Troyer upgraded my pulley back in the day when he installed it and should have been running 8psi+ but until I moved up here to CO I never had a boost gauge. The gauge now reads 6psi but I would need to take it back down to sea level and see if I really can get 8psi. Damn you Roush!

So when I was at Troyer's that means I was making 380rwhp/420rwtq on 6psi not 8psi like we thought. Wonder how much more she makes with the extra 2lbs back

Also, wouldn't this mean that anytime Troyer upgraded the stock pulley on a Roush blower that the blower would only let him tune A/F based off 6psi??? Now when we take this off and regain more boost the tunes will be lean. To me that would mean every Roush blower that came out of Troyer's shop would all be close to the same output since technically we are all running 6psi regardless of SC pulley and give/take exhaust, headers, efans, etc.

Can anyone verify you've gained boost back?

 

Troyer has a way of going around the solenoid but it is still limited and you won't see full boost

I speak with experience, I was in the same boat as you, got Troyer tune, got frustrated, called JDM, JDM sold me a 4lbs crank pulley, disconnected the solenoid, but now I'm making too much boost at 14PSI and over 500RWTQ LOL

I'm working out with JDM now to find a solution to get less boost, but this is highly frustrating because I now love my truck, this thing does rolling burnouts at 25mph, before I couldn't do rolling burnouts with Troyer's tune and the tune is a lot, I mean a lot more responsive with JDM

this is NOT Roush fault, Roush put that solenoid to protect your engine to make too much boost, it is the tuner that should have told you to disconnect the solenoid and make a proper tune
I first went with Troyer because on forums people say that Troyer has lots of experience with Roush, well tbh it's bs to me, JDM all the way, and their customer service is day and night vs Troyer