paxton torque booster/wastegate overview

[Luce202]

Preface with I highly recommend beefcakes product, 10/10. Also highly recommend lund tuning.

It seems like questions surrounding using a wastegate on paxtons is coming up frequently/every month. I thought I would make a video/summary with my experience. I'll preface with I'm not a guru expert but I do have a fair amount of experience in this area. Feel free to add more information. I hope this video helps anyone searching for info on this topic

.

Sponsored

 

[Biggsy]

Just so i understand this as well, the wastegate also prevent you from utilizing the full powerband correct? So if you have an 18 manifold you should be able to rev higher (i don't know the exact number) but if you have a 10psi spring and you reach that before 7k rpms then you want to upshift causing you to go back down the power band. So you never even reach the benefit of the 18 mani because you each max boost before then therefore makes having an 18 mani pointless. Do i have the right thinking? Hopefully that was clear lol.

 

[Safridi22]

But I thought the "torque" in "torque booster" meant gains in the mid-lower rpms?

 

[Luce202]

Just so i understand this as well, the wastegate also prevent you from utilizing the full powerband correct? So if you have an 18 manifold you should be able to rev higher (i don't know the exact number) but if you have a 10psi spring and you reach that before 7k rpms then you want to upshift causing you to go back down the power band. So you never even reach the benefit of the 18 mani because you each max boost before then therefore makes having an 18 mani pointless. Do i have the right thinking? Hopefully that was clear lol.

The benefit of the wastegate is to reach your targeted boost level sooner and hold it through the entire rpm curve.

For example, let's say for the purpose of discussion that you want to make 10 psi max. Lets consider 3 scenarios.

Scenario 1(no wastegate): You could use a pulley that reaches your 10 psi target at 7400 rpms which would not require a wastegate. However, with the slow steady linear increase in boost that comes from a centrifugal blower you will be at much lower levels of boost through the rpm curve....perhaps only 5lbs at 5000rpm, 7lbs at 6000rpm etc.

Scenario 2(no wastegate): So lets now say that you are still not using a wastegate and you want to reach your 10 psi target sooner. You can use a smaller pulley to bring the boost in quicker, but with no wastegate to bleed off the boost above your 10 psi target, the boost continues to increase with the rpm and you're now making more boost than your 10 psi target at the top of the rpm curve.

Scenario 3(with wastegate):If you use a wastegate to control your 10 psi max target, you can use a much smaller pulley that will produce boost much sooner and the wastegate will bleed off any boost above 10 psi, thus holding you at your target boost level of 10 psi. So while you will still have the same 10 psi max, you are now reaching it quicker...perhaps 8 lbs at 5000rpm using the wastegate with smaller pulley instead of the 5lbs you would get at that rpm using only a pulley to target max boost.

When it comes to your 18 manifold you mentioned, it will still serves it's beneficial purpose. The purpose of the wastegate is not to stifle power at the top end of the rpm curve, the purpose is to reach that max target sooner so you will still make the power up top from your targeted boost level, but also make more power down low as well. Best of both worlds situation.

You mentioned shifting once you reach the targeted boost level to "go back down to the powerband." You don't want/need to do this. The wastegate with smaller pulley doesn't shift the power, it just brings it in sooner due to the boost coming in sooner from the smaller pulley. You will still be making all the power up top you did before, it will just come in sooner due to the boost coming in sooner. Hope that helps! Let me know if it didn't answer your question.

 

[Biggsy]

The benefit of the wastegate is to reach your targeted boost level sooner and hold it through the entire rpm curve.

For example, let's say for the purpose of discussion that you want to make 10 psi max. Lets consider 3 scenarios.

Scenario 1(no wastegate): You could use a pulley that reaches your 10 psi target at 7400 rpms which would not require a wastegate. However, with the slow steady linear increase in boost that comes from a centrifugal blower you will be at much lower levels of boost through the rpm curve....perhaps only 5lbs at 5000rpm, 7lbs at 6000rpm etc.

Scenario 2(no wastegate): So lets now say that you are still not using a wastegate and you want to reach your 10 psi target sooner. You can use a smaller pulley to bring the boost in quicker, but with no wastegate to bleed off the boost above your 10 psi target, the boost continues to increase with the rpm and you're now making more boost than your 10 psi target at the top of the rpm curve.

Scenario 3(with wastegate):If you use a wastegate to control your 10 psi max target, you can use a much smaller pulley that will produce boost much sooner and the wastegate will bleed off any boost above 10 psi, thus holding you at your target boost level of 10 psi. So while you will still have the same 10 psi max, you are now reaching it quicker...perhaps 8 lbs at 5000rpm using the wastegate with smaller pulley instead of the 5lbs you would get at that rpm using only a pulley to target max boost.

When it comes to your 18 manifold you mentioned, it will still serves it's beneficial purpose. The purpose of the wastegate is not to stifle power at the top end of the rpm curve, the purpose is to reach that max target sooner so you will still make the power up top from your targeted boost level, but also make more power down low as well. Best of both worlds situation.

You mentioned shifting once you reach the targeted boost level to "go back down to the powerband." You don't want/need to do this. The wastegate with smaller pulley doesn't shift the power, it just brings it in sooner due to the boost coming in sooner from the smaller pulley. You will still be making all the power up top you did before, it will just come in sooner due to the boost coming in sooner. Hope that helps! Let me know if it didn't answer your question.

That was perfect! Thank you very much! I forgot you did mention in the video that it holds at that boost level whereas i was thinking that it drops. Perfect explanation for me. Thanks again!

 

[aleccesarenriquez]

I'm going to reiterate what OP said but with pics.

ELI5:

First, you have to understand how TQ affects HP.

HP is just torque multiplied by rpm/5252. That means that HP is a direct result of how much torque your motor produces at a given rpm.

In other words, whenever your make a modification on your car to increase your HP, you are really just increasing your torque curve (or you were able to change your maximum rpm).

Take a look at the above pic, a typical example of a Twin screw vs a Turbo car. The middle lines are TQ curves and the other ones are obviously HP.

THE ABOVE CARS MAKE THE SAME PEAK HP. However, the peak TQ of the orange line is higher. So let's say the green car makes 750/500 and the orange car makes 750/600. How does that affect a race for example: if they start at 4500 rpm (i.e. a little bit after the intersection) and race to 7500 rpm, and ALL other factors are the same (weight, shifting, aero, start time, etc.), then the orange car will be faster.

In other words, with all other factors constant, to be faster than another car, you have to be making more torque at the same rpm.

Now it should make sense why a torque booster increases horsepower. A torque booster is called that because that's what it does: it increases the torque output of your motor. This directly affects HP since at the same rpm, you'll be making more torque, which means you'll be making more HP.

Now looking at this pic, this is what a dyno could look like before and after the wastegate.

In this scenario, before and after the wastegate, you're making the similar final HP. However, the increase in air from the smaller pulley means you're increasing torque output from the motor. All that the wastegate does is release the extra air when you've hit the spring threshold of boost pressure (which is why the HP curve becomes flat). In this scenario, the wastegated car will be much faster than the non wastegated car (with a larger pulley), because at every point in the rpm, you're making more HP except the end of the curve, where it's the same since you're cutting it off. Notice you'll reach max power much sooner though and hold for a duration of time.

Keep in mind, without the wastegate AND the small pulley, you'd make much more power than both of the examples. The point of the wastegate is to use a smaller pulley/increase boost but operate in safer conditions. The 3.33 pulley offered by Paxton is a small pulley that might start to stress the limits of the stock car (motor, blower, and trans) without a wastegate.

 

[Biggsy]

@Luce202 so just out of curiosity why did you go with a 10# spring when the motor can take more? Just being safe?

 

[Luce202]

@Luce202 so just out of curiosity why did you go with a 10# spring when the motor can take more? Just being safe?

The car is a nice weather daily and I am currently on pump 93 just for convenience. I rarely do any racing so it’s more just for my own entertainment. 10lbs puts a smile on my face every time so I figured keep it relatively safe on the engine.

 

[robmustang201528]

Preface with I highly recommend beefcakes product, 10/10. Also highly recommend lund tuning.

It seems like questions surrounding using a wastegate on paxtons is coming up frequently/every month. I thought I would make a video/summary with my experience. I'll preface with I'm not a guru expert but I do have a fair amount of experience in this area. Feel free to add more information. I hope this video helps anyone searching for info on this topic

.

I gonna rip that fucking boost controller out my car. Hits 12 lbs then drops. Where can I get a 12lb spring from? I have the V7JT vortech with a 14lb wastgate spring. I do more roll racing then digs. 40-150 60-150. The blower I have is oil fed and i plan on going past 7300 rpm. I also have a 8 rib 331 pulley. Will i still over spin the blower even if my blower is oil fed? Thanks for the video.

 

[aleccesarenriquez]

I gonna rip that fucking boost controller out my car. Hits 12 lbs then drops. Where can I get a 12lb spring from? I have the V7JT vortech with a 14lb wastgate spring. I do more roll racing then digs. 40-150 60-150. The blower I have is oil fed and i plan on going past 7300 rpm. I also have a 8 rib 331 pulley. Will i still over spin the blower even if my blower is oil fed? Thanks for the video.

What head unit is it? You need to look at the max rpm of the blower (ie paxton 2200sl is 52k), then determine how many revolutions the 3.33 causes at your redline. If it’s less than the max, you’re good.

 

[robmustang201528]

What head unit is it? You need to look at the max rpm of the blower (ie paxton 2200sl is 52k), then determine how many revolutions the 3.33 causes at your redline. If it’s less than the max, you’re good.

Vortech V7JT its oil fed

 

[robmustang201528]

Vortech V7JT its oil fed

331 pully

 

[Biggsy]

Vortech V7JT its oil fed

You will be fine. Max is 60k

 

[robmustang201528]

You will be fine. Max is 60k

Thanks

 

[robmustang201528]

The paxton's are not oil fed?

Sponsored