Mustang GT V8 5.0 2016 Whipple Supercharger now with 3.375'' pulley

[dperformance]

Hi guys,

I wanted to go for more power so I decided to change from 3.75'' to 3.375'' pulley as Whipple told me it will give me 3 PSI more. Unfortunately, it is giving me the same power on dyno and is barely making 0.5-0.8 psi more than before. Does anyone can help me in case there is a limiter I haven't seen on my calibration. Also on my log I cannot find anything wrong.

Thanks in advance.

[tbrtuning]

Belt slip maybe? Are you going by what you're logging for MAP for more boost or have a reading off a line that sees boost?

[dperformance]

I don't think that belt is slipping because Whipple sent me the belt, so they should have sent me a better belt with more grip, right?
I'm looking at the MAP I'm logging, I know it's calculated and not directly measured, but it should give me more power with a smaller pulley.
Have you looked the file?

[small tuner]

any mods done to the engine? KN retard table set to zero!! should not be zero. what fuel type.

[dperformance]

Whipple calibration started like that! I'm using mix with C-16. But it wont detonate because we are at 7,800 feet over sea level so internal compression is lower. I think it should be something with some kind of limit, because super should do more PSI.

[dperformance]

Do you guys know if there is a way to adjust the valve that is limiting boost on Whipple SCs?

[txcharlie]

The bypass valve is not adjustable, it's either open or closed. If you suspect the BV then it should be tested/replaced. You also need to log your cam timing to see which MP is used in WOT. The cams may have too much overlap, allowing much of your boost to bleed off.
How much power did it pick up with the smaller pulley? You airflow numbers look low for that pulley. Do you have longtube headers?

[Chops44]

If you are modifying the whipple tune make sure the following guardian settings are turned off especially when running a smaller pulley:

Octane adjust...not needed since you are running good fuel
"knock limiting" this will not disable spark knock, retard knock limiting can hold back throttle
"overload limiting " this can kick in if you have smaller pulley
"CHT Limiting " somtimes when running hard this can start limiting throttle .

[LastPlace]

If you are modifying the whipple tune make sure the following guardian settings are turned off especially when running a smaller pulley:

Octane adjust...not needed since you are running good fuel
"knock limiting" this will not disable spark knock, retard knock limiting can hold back throttle
"overload limiting " this can kick in if you have smaller pulley
"CHT Limiting " somtimes when running hard this can start limiting throttle .

Hptuners scanner might be able to adjust some of these guardian features

[17whipple]

Were you able to figure it out? I couldn't open tune but from log looks like the bypass was dumping boost load is very low. I am running same pulley. Even at 10lbs I see 168. Also the maf isn't pulling in much at all but cant read tune.

[veeefour]

Whipple calibration started like that! I'm using mix with C-16. But it wont detonate because we are at 7,800 feet over sea level so internal compression is lower. I think it should be something with some kind of limit, because super should do more PSI.

He's right tho - you cant runs 25' of timing with boost even with "lowered compression" and race fuel. You are going to grenade your engine.

I have various stock Whipple calibrations and they don't do that in their tunes.

But your problem is not tune related, something is not right mechanically. Look for leaks or bad by-pass valve.