Whipple part throttle manners/power question.

Still trying to decide if I am going TVS or Whipple, although Whipple seems to be ahead at least for today. Here's my story. lol

Took my car on a long road trip over the holiday weekend and it hit me like a ton of bricks. I am looking at blowers based on dyno numbers, track times, driver feedback etc which is almost always WOT based. However the whole 600 mile round trip I never hit WOT once. I rarely do unless I am racing or showing off. My concern should really be power and drivability at part throttle. For example carving up a mountain road and easing on the throttle out of a turn, maybe pushing the car to 4kish before the next turn. I realize that Whipple makes some good power at low RPM but will I lose that through the BOV at part throttle?




So my question is for the Whipple guys, how is your part throttle drivability and power? When does boost start coming on?

edit: You’ll have to excuse me because my last blower car was a Novi 2000 on a 4.6 Cobra back in the day. That car felt more lethargic and has worse drivability at part throttle until I really laid into it and got over 4k. Granted that was a big centri and we’ve got 20 years of tuning technology behind us now.

mine drives literally like stock up to about 30-40% throttle. It gets a touch of surging above that throttle percent where boost starts to build and I can feel the bypass starting to fluctuate in position a little. There is zero light switch effect like some other cars have, never just takes off on me, in fact in my opinion the transition from part throttle to full throttle is a touch delayed, not in a bad way, but its not instantaneous and purposefully so.

I plan to work out the surging with my own tuning, but I also think I may have a leaky bypass diaphragm as its not holding vacuum too well, which could be contributing.

On cold starts, sounds like a bag of ass if you have catless headers. It purposefully runs negative timing on cold starts to light off the catalytic converters, if you don't have any itll sound like its running really rough. I eliminated the negative timing in the tune and now its stock when it fires up. I also notice in the first two or three accelerations through the gears, it has an RPM hang after you lift the throttle. This may also be related to the leaky diaphragm but I will be logging to check for tune issues in the next week. Happy to share what I find.

In general all these systems CAN drive like stock, its all in the tune. I have to say Whipple did a fantastic job getting the car near stock for anything other than WOT.

Specifically about your power loss question and transitioning into power, most tunes and blowers are setup to have stockish power output up to about 30-40% throttle. the 50-70% zone is the toughest to tune and not pop pistons, as you are now into boost but below richer fuel command. But you should not expect additional power at anything other than WOT when comparing NA to a boosted application.

TooSoonJunior said:

Specifically about your power loss question and transitioning into power, most tunes and blowers are setup to have stockish power output up to about 30-40% throttle. the 50-70% zone is the toughest to tune and not pop pistons, as you are now into boost but below richer fuel command. But you should not expect additional power at anything other than WOT when comparing NA to a boosted application.

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Great info, thanks. Definitely curious to hear if that little bit of rev hang/surging is from the leaky diaphragm when you figure it out.

TooSoonJunior, what tune do you have? Reason I ask is that I have a similar setup to you, but I would not describe the way my car drives the way you did. Mine is very smooth pulling right from idle. No where near 30% throttle is needed to feel that it pulls harder than stock. Of course as rpms rise, the boost is instantly ready to be used. I would describe it like a much bigger motor than what it is. Torque is very good at lower revs and partial throttle in my opinion. Can it act like stock? Yes, if you are trying to be quiet, and barely getting into the gas. Cold starts sound awesome, touch the button, and instant light off. LOUD for about 5 seconds, then very pleasant. As was mentioned, the bypass valve in the supercharger is vacuum operated. So AS SOON AS you step on the gas, and vaccum drops, the valve is closing, allowing the boost to go to the motor. Great thing about the whipple is it does not have to be spun up to high rpm to make pressure. Don't get me wrong, the faster it spins, the more it makes, but it's making boost at lower revs too. Don't think the TVS works the same way. Could be wrong though.

On the stock Whipple tune.

The only reason it feels like it has more torque than stock is Whipple tweaked the throttle command tables to be higher than even sport mode when in normal mode, giving you the sense of all this "torque" on tap, when all it's doing is commanding 15% power when you give it 10% throttle. Knowing this takes out the "wow" factor for me lol

I don't know what the whipple tune does, but I have looked at my logs and compared accelerator pedal position to actual throttle opening, and I don't see what you are describing. The lines basically parallel each other. If anything, I'm not getting as much actual as I'm asking for most of the time. Kinda hard to tell exactly, because one is %, and the other is degrees. One maxes out at 100, and the other at about 85. I suppose I could do the math to make the degrees into a percentage, but I haven't.

I wish I would have logged the car when it was stock, to compare to how it is now. Would have been interesting to see how much changed. I know 40 to 140 takes a lot less time now :-).

What is interesting is Whipple just adds 20% to the entire pedal output, even so at 90% its putting out 108% and 100% its out out putting 120%. That would make 100% out put happen around 84%.

Sport mode does it the other way where they cap it at 100% and give a relative 20% from 25% up. So that 84% is 100% and 100% is 100%. Sport mode is actually slightly more aggressive because of this.

But I have good news, Whipple does more than a trick of the pedal. They actually demand more torque in first gear at partial throttle, and less torque at the higher RPMS. In the higher gears they demand less torque at partial throttle, until the higher RPMS. this all translates to different engine output in different gears at partial throttle.
WOT is the same for all gears.
The attached picture is where I compared a stock whipple tune to the same stock whipple tune and copied first gear values over a higher gear. HPT can read these tunes, but as you can see from the throttle position% being all 125% in first and second, its far from perfect. This information may not even be accurate.

@Ironair That's great feedback, thank you. What tune are you running?

@markmurfie Again great info, I think what I am getting out of it is that part throttle response will be improved in lower gears?

Is this something that can be adjusted?

Ken B @ PBD

SVT-DADDY said:

Still trying to decide if I am going TVS or Whipple, although Whipple seems to be ahead at least for today. Here's my story. lol

Took my car on a long road trip over the holiday weekend and it hit me like a ton of bricks. I am looking at blowers based on dyno numbers, track times, driver feedback etc which is almost always WOT based. However the whole 600 mile round trip I never hit WOT once. I rarely do unless I am racing or showing off. My concern should really be power and drivability at part throttle. For example carving up a mountain road and easing on the throttle out of a turn, maybe pushing the car to 4kish before the next turn. I realize that Whipple makes some good power at low RPM but will I lose that through the BOV at part throttle?




So my question is for the Whipple guys, how is your part throttle drivability and power? When does boost start coming on?

edit: You’ll have to excuse me because my last blower car was a Novi 2000 on a 4.6 Cobra back in the day. That car felt more lethargic and has worse drivability at part throttle until I really laid into it and got over 4k. Granted that was a big centri and we’ve got 20 years of tuning technology behind us now.

Click to expand...

Not a whipple guy but your comments were exactly what went through my mind when I was deciding on power adder. In the end I went Procharger because it's my daily driver and like you say I put my foot in it a few times a day and always while rolling so don't need mad torque from a dig. Below 50% throttle it drives like stock but mash the gas in 1st or 2nd and it doesn't matter if it's a centri or twin screw you're getting wheel spin and shit startes coming at you real fast. More than happy with my choice considering I pulled up to a new Audi R8 recently and whilst he got me by a car from the dig I'd pulled a car on him by 3rd gear.

Without a heavy foot, my Whipple drives like stock. It's quite boring actually.