What gauges is a must for tuning new twins

[joelc79]

My truck is almost complete with some new twins. For those of you who actually fine tune your twins what is the gauges i'll need. Will i need two boosts and a drive? Will both the boost gauges need to be 100psi?

[Santa Gertrudis]

Everyone I have seen with twins has two 100psi boost gauges and a 100psi drive. I guess it all depends on the size of your twins though.

[ozone burner]

i have a 30psi in between the two and a 60 overall it just depends on the overall boost your going to make do to fueling but you will figure that out with your drive pressure gauge that will tell you when you need to have your wategate open.to make it 1to1 and not be blowing hot air.

[joelc79]

Everyone I have seen with twins has two 100psi boost gauges and a 100psi drive. I guess it all depends on the size of your twins though.

Thats what i was thinkin, thanks guys

[Santa Gertrudis]

No problem. If I were in your situation, I would just go ahead and get the big gauges even if you don't need them. That way if you go bigger, your gauges are still fine.

[coon smile]

My truck is almost complete with some new twins. For those of you who actually fine tune your twins what is the gauges i'll need. Will i need two boosts and a drive? Will both the boost gauges need to be 100psi?

If you already have a 60psi gauge, just use that to measure your primary. You will def. want a 100psi gauge for total system pressure and drive.

[gwhammy]

My 3b isn't wastegated so I just unhook the cold pipe and set the wastegate on the second stage.

[Charles]

From a pure ergonomics standpoint, all preference aside... you would want the difference in gauge readings to equal the intended difference in boost you plan to run.

For instance, I run ~25lbs on my first stage and ~60 to 70lbs on the manifold. By using a 35lb gauge for the first stage, and a 100lb gauge for the manifold the gauges move in unison, and when the stages are balanced both needles are parallel to one another.

Makes it real easy for the eye to detect a control problem if one stage gets out of balance.

I suggest a 35 and a 100 for a two stage setup.

And a 100psi drive pressure gauge works well for most trucks.

[joelc79]

^ Makes sense, Thanks

[Scooter's Roofing]

100 manifold, 60 interstage, 100 drive

[CD in NM]

I am GLAD to see this thread. I am installing a set of towing twins and am trying to figure out how to get them balanced and what gauges to have. I am also trying to figure out how to plumb these gauges up, where to connect my gauges for the best readings.

Previously, with my single/stock turbo, I had a boost connection at my intake horn, I am wondering if that is still a good place to get my boost reading OR if I should tap somewhere else?

I also am guessing (emphasis on the guessing) that I need to make a coil with a filter and come off my exhaust manifold for the drive/exhaust pressure?

My wastegate is physically located on my top turbo (62/65/12), my wastegate hose is connected to my bottom (S475). I am assuming that this is the standard way to connect the wastegate?

All this is NEW to me, I guess I also have to learn about the specific terminology of things to better understand it all. Is there someplace I can go to see pics and read about how all this works? A diagram or two of flow and some reading materials to understand would be greatly appreciated/helpful.

[ENafziger]

Is it beneficial to have an intermediate "drive" pressure between the turbos? Would this show the wastegate pressure that the turbo is bypassing to the primary?

--Eric

[XLR8R]

Sure - helps to balance the load on the turbine wheels, and shows WG movement... also allows primary drive pressure ratio to be seen.

We use a bung on the hot pipe and a quick-change manifold to read PSI from up to 6 locations on a pair of boost gauges.

[JasonCzerak]

If I had to do the guages all over again... Or add anymore then the 8 aftermarket ones that will be in my truck.....

I'd sell them all, Get a datalogging ISSPro setup and run a few on the pillar and maybe on the column.

DATALOG THE REST.

Your eyes can do like 1.2 things at a time.. Either their on the road, maybe catching a "warning light", or their on the gauge.

I don't have a data logger, but I'll do one soon I'm sure.

Plus the wire mess that'll clean up! :)

[coon smile]

If I had to do the guages all over again... Or add anymore then the 8 aftermarket ones that will be in my truck.....

I'd sell them all, Get a datalogging ISSPro setup and run a few on the pillar and maybe on the column.

DATALOG THE REST.

Your eyes can do like 1.2 things at a time.. Either their on the road, maybe catching a "warning light", or their on the gauge.

I don't have a data logger, but I'll do one soon I'm sure.

Plus the wire mess that'll clean up! :)

Yes, I have the same problem. Especially when you are WOT screaming down a 1/4 mile track.

I talked with some guys about it (boost pressure specifically), and they recommended pressure gauges that hold max pressures, which reset with a button. It's not going to compare to a data logger, but you don't have to move your focus between 5-8 different gauges in one 1/4 mile stretch.

Kyle

[JasonCzerak]

yep.. reset button's would be nice too.

[lcaad1249]

I've got the SPA dual gauges that record my peaks. I've got the Boost/EGT and then a Pressure/Pressure. They store the maxes and are resetable.

[joelc79]

Does anyone know if ISSPRO has a drive psi gauge, i thought they did but i can't find it.

[joelc79]

I've got the SPA dual gauges that record my peaks. I've got the Boost/EGT and then a Pressure/Pressure. They store the maxes and are resetable.

So i assume you use the boost/egt for drive and egt? The other psi/psi is your two actual boost gauges? Also on their site i only see the egt reading up to 1000 Deg. Could you let me know who you wen through?

[lcaad1249]

So i assume you use the boost/egt for drive and egt? The other psi/psi is your two actual boost gauges?

You can set them up however. I've got overall boost with EGT but I've had that gauge setup for years and then added a 60 # dipricol for primary boost so when I got this dual gauge a month or two ago I just lumbed drive and primary boost to it.

[CD in NM]

ISSPRO EV2's have an exhaust pressure gauge, it uses the same sensor as far as giving you your drive pressure, just doesn't say drive pressure.

[Charles]

100 manifold, 60 interstage, 100 drive


Who around here is going to be running anywhere near 60lbs on a single stage? If I were to pin my 35lb gauge with the first stage, and do the same with the second we'd be talking over 120lbs of boost. That's the limit for a balanced 120psi of boost...

I personally think that reading up to 120psi is sufficient gauging for the OP considering that the 100lb manifold gauge would be on the stop at that point anyway. If a balanced system were to run 60lbs per stage we'd be talking 365lbs of boost. Just a bit outside the practical usage realm IMHO, and you would have to be using a hydraulic pressure gauge to read manifold pressure at that point anyway.

If you run a 60lb and a 100lb, and you balance the stages the gauges will never point in any sort of meaningful way. The 60lb gauge will always be lagging behind but not even to a proportionate amount. No relation to the movement of the 100lb gauge.

With a balanced two stage system a 30 or 35lb and a 100lb produces gauge needle movement that is very easy for your eye to detect without ever having to physically read the gauge. Out the corner of your eye you can instantly tell that everything's good to go because the needles will be parallel or close to it whenever the chargers are running balanced.

Now don't get the idea that I'm trying to tell anyone how to put gauges in their own truck, or that running a 60 and a 100 is wrong. I'm just taking another stab at explaining why beyond preference, it makes sense to have the ratio between gauge faces match the ratio the chargers are actually going to run. It makes the readings meaningful and intuitive to tune.

After all, this is nothing more than an ergonomics discussion anyway.



Also, like Jason mentioned, one gauge is about all that's the mind is good for at WOT. I datalog each stage boost, as well as overall drive and will pull over, review the log and make tuning changes whenever I tune the chargers.

Other than that, I always know I'm still okay when I see my needles staying parallel. And the times that I've blown a wastegate signal line I've caught it because even though I wasn't looking at the boost gauges, my eye caught the fact that the needles were all out of whack.

[lcaad1249]

I was always told a 1/2 primary/combined boost ratio. For example on my setup I get primary boost right at 40 and combined around 85. I thought that was the best way. Is that not what you do Charles?

[JasonCzerak]

....

Also, like Jason mentioned, one gauge is about all that's the mind is good for at WOT. I datalog each stage boost, as well as overall drive and will pull over, review the log and make tuning changes whenever I tune the chargers.

....



Another thing I've seen on race cars and I think planes? Is orientate each gauge so that the "normal" (oil pressure, voltage, fuel pressure) or "max" (boost, egt, water,) reading is pointing to 12 o'clock.... If a gauge isn't straight up, then there's something wrong.

[CD in NM]

Well, let me throw this out there about something I was told to do regarding getting a primary(bottom) turbo boost reading - I was told to just 'T' into the wastegate line going to the bottom primary turbo. I already have a boost guage to my intake horn, I was looking for the second boost connection when I got that suggestion about where to connect a second gauge.

I have a 60 boost gauge and a 40 boost guage that I was considering using for information. So, the 40 would go to my intake horn? and the 60 to that wastegate T?

XLR8R - are you coming to the Albuquerque dyno meet this weekend ?? If so, could I bother you to bring me a few things with you ??


CD

[JasonCzerak]

40 in the T
60 in the horn.

The T is a neat idea.

[Charles]

I was always told a 1/2 primary/combined boost ratio. For example on my setup I get primary boost right at 40 and combined around 85. I thought that was the best way. Is that not what you do Charles?

At 85lbs on the manifold and 40 on the first stage you are far from balanced.

If the first stage is making 40psig, that's a PR of 3.72:1. If the system were balanced, then each stage would be doing equal work, meaning the PR would be the same for each, meaning the second stage would also need to be running a PR of 3.72:1. Well, if both stages were running that PR, or "40lbs" the total manifold pressure would actually be 188lbs of boost....

:eek:


Not exactly the 85lbs you have on the manifold is it? The reason for this is that your second stage isn't running a balanced PR of 3.72:1, it's actually only running a PR of 1.82:1, or "12lbs" of boost. See how insanely lopsided that is?

Your first stage is working over twice as hard as the second. The second stage is just loafing along while the first does all the work.

At 85psig on the manifold, a balanced setup would be running a first stage PR of 2.6:1 or 23lbs of boost.

This is why when running 65 to 70lbs of boost I run a first stage pressure between 20 to 25psi. It's balanced. And drive pressure agrees. If I run the chargers much outside the range in either direction the boost:drive starts falling off.

[JasonCzerak]

At 85lbs on the manifold and 40 on the first stage you are far from balanced.

If the first stage is making 40psig, that's a PR of 3.72:1. If the system were balanced, then each stage would be doing equal work, meaning the PR would be the same for each, meaning the second stage would also need to be running a PR of 3.72:1. Well, if both stages were running that PR, or "40lbs" the total manifold pressure would actually be 188lbs of boost....

:eek:


Not exactly the 85lbs you have on the manifold is it? The reason for this is that your second stage isn't running a balanced PR of 3.72:1, it's actually only running a PR of 1.82:1, or "12lbs" of boost. See how insanely lopsided that is?

Your first stage is working over twice as hard as the second. The second stage is just loafing along while the first does all the work.

At 85psig on the manifold, a balanced setup would be running a first stage PR of 2.6:1 or 23lbs of boost.

This is why when running 65 to 70lbs of boost I run a first stage pressure between 20 to 25psi. It's balanced. And drive pressure agrees. If I run the chargers much outside the range in either direction the boost:drive starts falling off.

So, why does it need to be this balanced? don't you want the big charger that's more efficient taking in larger chunks of air to work while the little one free wheels a bit to no heat up the air?


Edit: <--- knows crap about twins. I abuses a small single, so meh.

[XLR8R]

XLR8R - are you coming to the Albuquerque dyno meet this weekend ?? If so, could I bother you to bring me a few things with you ??


CD

Sure Carol - we help sponsor it every year... already bringing hard parts, but let me know what you need so we can get it loaded today. :Cheer:

[Charles]

So, why does it need to be this balanced? don't you want the big charger that's more efficient taking in larger chunks of air to work while the little one free wheels a bit to no heat up the air?


Edit: <--- knows crap about twins. I abuses a small single, so meh.


Thermal efficiency is highest when each compressor is operated most efficiently. Why would you work a charger to 40lbs, making a good bit of heat and getting nothing from the second only making 12 when you could have them both sharing the load making an honest 20?

If you had two guys unloading seed bags from a flatbed why would you have one of them running back and forth sweating his ass off with 2 bags while another guy was only carrying one at a time? Not making efficient use of your help.

This is the whole point of compounding. Splitting the load between chargers. Get far enough away from balanced and you might as well just run a single, as you're not taking advantage of the benefits to compounding.

[CD in NM]

XLR8R - I need a couple of your gauge pods, black is fine. I also need a 90* pyro probe - not sure of the tip length - 1-1/2 or 2-1/2, maybe somewhere in between ?? I'd like to take a look at that multi/switch setup you have for using multiple stuff that is controlled by a couple/few switches - I am assuming the switches are DPDT? Dodge could have at least given us a dash to work with . . If I think of anything else I'll give you a call. I am heading up to Albq today, have an appointment at Melloy in the AM.

Thanks. Carol

[CD in NM]

40 in the T
60 in the horn.

The T is a neat idea.


That's what I thought Jason - THANKS for the confirmation.
I thought the 'T' in the wastegate hose was a good idea too. So many things to connect up, too many tight spaces to put it all in . .


CD

[Dockboy]

The only way to tune twins ;)

Grey is RPM
Red is manifold boost
Blue is primary boost

http://www.competitiondiesel.com/forums/attachment.php?attachmentid=25176&stc=1&d=1273787134

[Charles]

The only way to tune twins ;)

Grey is RPM
Red is manifold boost
Blue is primary boost

http://www.competitiondiesel.com/forums/attachment.php?attachmentid=25176&stc=1&d=1273787134



That's how I did it, plus a drive pressure transducer.

[Dockboy]

Same pass

Secondary (manifold) boost and wastegate control line only

http://www.competitiondiesel.com/forums/attachment.php?attachmentid=25177&stc=1&d=1273787898


Primary boost and wastegate control line only

http://www.competitiondiesel.com/forums/attachment.php?attachmentid=25178&stc=1&d=1273787898

[joelc79]

well hopefully when these stand alone ecm come out they will have the data logger features nailed down as well. I would rather spend the 4K on that then acomplete datlogger system with all the extras for the same price.
I do agree that this is the true way for now

[Charles]

Here's a screenshot I took a while back to show people the capability of the PCS.

On this one from left to right it's boost, drive and mph. Then down from mph is trans temp.

The animation on the left is actual throttle position.

http://inlinethumb39.webshots.com/44518/2934225320082519711S600x600Q85.jpg


Awesome doesn't even begin to describe tuning compounds like this. When you then realize my gates were being run from two 4 port solenoid valves and that adjusting them didn't even require me to take my seatbelt off, but to simply change a few duty cycle values in the PCS, you realize how sweet computers can be.

[dieselduck]

So what's the easy answer? 2 boost gauges enough? If you balance out the 2 turbos then thats all you can do right? Drive pressure is what it is correct? I currently only have 1 boost gauge at the manifold, thinking the T at the waste gate sounds like the easiest for the 2nd gauge. Towing twins here no 100psi boost maybe 60.

I'm not a racer so maybe i'm missing something.:what:

[ENafziger]

I presume "tuning" the twins is limited to adjusting the wastegate(s) without a standalone ECM?

[Charles]

So what's the easy answer? 2 boost gauges enough? If you balance out the 2 turbos then thats all you can do right? Drive pressure is what it is correct? I currently only have 1 boost gauge at the manifold, thinking the T at the waste gate sounds like the easiest for the 2nd gauge. Towing twins here no 100psi boost maybe 60.

I'm not a racer so maybe i'm missing something.:what:


Not completely. Because of differing turbine wheel and housing sizes the sweet spot isn't always going to be when the compressors are perfectly balanced. And even then, they can be perfectly balanced at any of an infinite number of manifold pressures...

The drive pressure gauge will let you know when increased boost is gaining you more drive than anything else, and let you know when you're pushing the setup too hard, and you should back back down. Even with the stages balanced.

For instance, they can be perfectly balanced at 60, 70, 80, 90 or any other amount of boost, yet the boost:drive isn't going to just stay cozy forever. At some point you'll start to see drive start to increase quickly while boost doesn't.

Look in my datalog screenshot. You'll notice at 70lbs of boost I was at 80lbs of drive. While not horrible, I actually backed it back down to ~65lbs where the boost:drive is closer to 1:1. Power gained after drive starts taking off is marginal, but stress isn't. The cost:benefit starts to get unfavorable as you push the chargers too hard.

[dieselduck]

I have Rips twins s300/s400 the 64 with the small 12 outlet, flux 2 tips and a stock cp3 and a Smarty with the standard programing (not TNT). Yes I guess I will only be adj the one waste gate.

Charles thanks for the explanation on drive pressure. I don't think I will have enough fuel with the stock cp3 to build much drive pressure, do you?

[Dockboy]

The animation on the left is actual throttle position.

http://inlinethumb39.webshots.com/44518/2934225320082519711S600x600Q85.jpg




And the actual size of Charlie's calf!!!!:hehe:

Sorry buddy...............couldn't resist:kick:

[CD in NM]

Now THAT is some kind of funny ^^^^^.

What software is that ?? While I am in no way some kind of computer geek, I could get into something like that, or give it one he!! of a good try learning how to use it.

Carol

[Charles]

And the actual size of Charlie's calf!!!!:hehe:

Sorry buddy...............couldn't resist:kick:



You look scrappy, but I would roll you up old man...

;)

[dieselduck]

Charles is this a set it and forget it kind of thing (balancing the compounds), or is this something a person needs to keep an eye on?

[Smoke]

Nice info and software shots.

[Charles]

Charles is this a set it and forget it kind of thing (balancing the compounds), or is this something a person needs to keep an eye on?

Both...

It's set if and forget it...... until you blow a reference line and snap a 100lb gauge before you know it.

That's when having the needle movement meaningful holds merit IMO. I've blown signal lines multiple times, on first and second stages having boost jump up to 70, 80, 90 and higher on me. The truck feels different, sounds different and within the second I know it's boost when I see one of the gauges way out of whack, either high or low. High if it's a blown signal line, low if it's a blown boot.

If you run a setup for enough years lines are going to blow, and boots are going to pop.

[ENafziger]

I'm a little slow, but I think I'm finally getting it.

I've always heard in a twin turbo configuration, you want the primary and secondary to each do half of the work. That's true.

I've also heard from everyone (except Charles) that this means you want to adjust the wastegate so the primary is making half the boost of the secondary. This is where everyone gets it wrong!!! Somewhere along the line, someone wrongly made the assumption that boost is the same as work, and everyone else repeats it. Thanks for getting me thinking Charles.

So, if I have this right in my head, "work" is equivalent to pressure ratio...and NOT boost. Thus, in simple terms, a balanced twin turbo system will have each turbo doing equal amounts of work...or they will both be operating at similar pressure ratios.

Pressure Ratio is defined as: Pabsolute,in / Pabsolute,out

So, assuming atmospheric pressure of 14.7 psia, the PR formula for the primary is (PSIg + 14.7) / 14.7.

The PR formula for the secondary becomes (PSIg,secondary + 14.7) / (PSIg,primary + 14.7).

Assuming I'm finally getting a grasp on this, resultant PRs for the primary and secondary would look like this:

Primary Turbo Secondary Turbo
Boost PR Boost PR
0 1.00 0 1.00
1 1.07 3 1.13
2 1.14 6 1.24
3 1.20 9 1.34
4 1.27 12 1.43
5 1.34 15 1.51
6 1.41 18 1.58
7 1.48 21 1.65
8 1.54 24 1.70
9 1.61 27 1.76
10 1.68 30 1.81
11 1.75 33 1.86
12 1.82 36 1.90
13 1.88 39 1.94
14 1.95 42 1.98
15 2.02 45 2.01
16 2.09 48 2.04
17 2.16 51 2.07
18 2.22 54 2.10
19 2.29 57 2.13
20 2.36 60 2.15
21 2.43 63 2.18
22 2.50 66 2.20
23 2.56 69 2.22
24 2.63 72 2.24
25 2.70 75 2.26
26 2.77 78 2.28
27 2.84 81 2.29
28 2.90 84 2.31
29 2.97 87 2.33
30 3.04 90 2.34
31 3.11 93 2.36
32 3.18 96 2.37
33 3.24 99 2.38
34 3.31 102 2.40
35 3.38 105 2.41
36 3.45 108 2.42
37 3.52 111 2.43
38 3.59 114 2.44
39 3.65 117 2.45
40 3.72 120 2.46

(I can't get the columns to display correctly. The first column is Primary turbo boost, second is Primary turbo PR, third is Secondary turbo boost, fourth is Secondary turbo PR)


Thus, if I'm wanting to run a total boost of 60 psi as measured by my gauge at the intake manifold, I want to wastegate the primary turbo to approximately 17 psi...since this is where the pressure ratios are equal.

If I went with conventional thinking, I would run 60 psi total, and 30 psi in the primary. However, doing so would put the primary at a PR of 3.04, which is more than likely well out of its highest efficiency range on the compressor map.

...and that's why Charles says to use a 35 psi gauge for the primary and a 100 for the secondary!


Comments?

--Eric

[bsmith]

I'm a little slow, but I think I'm. finally getting it.

I've always heard in a twin turbo configuration, you want the primary and secondary to each do half of the work. That's true.

I've also heard from everyone (except Charles) that this means you want to adjust the wastegate so the primary is making half the boost of the secondary. This is where everyone gets it wrong!!! Somewhere along the line, someone wrongly made the assumption that boost is the same as work, and everyone else repeats it. Thanks for getting me thinking Charles.

So, if I have this right in my head, "work" is equivalent to pressure ratio...and NOT boost. Thus, in simple terms, a balanced twin turbo system will have each turbo doing equal amounts of work...or they will both be operating at similar pressure ratios.

Pressure Ratio is defined as: Pabsolute,in / Pabsolute,out

So, assuming atmospheric pressure of 14.7 psia, the PR formula for the primary is (PSIg + 14.7) / 14.7.

The PR formula for the secondary becomes (PSIg,secondary + 14.7) / (PSIg,primary + 14.7).

Assuming I'm finally getting a grasp on this, resultant PRs for the primary and secondary would look like this:

Primary Turbo Secondary Turbo
Boost PR Boost PR
0 1.00 0 1.00
1 1.07 3 1.13
2 1.14 6 1.24
3 1.20 9 1.34
4 1.27 12 1.43
5 1.34 15 1.51
6 1.41 18 1.58
7 1.48 21 1.65
8 1.54 24 1.70
9 1.61 27 1.76
10 1.68 30 1.81
11 1.75 33 1.86
12 1.82 36 1.90
13 1.88 39 1.94
14 1.95 42 1.98
15 2.02 45 2.01
16 2.09 48 2.04
17 2.16 51 2.07
18 2.22 54 2.10
19 2.29 57 2.13
20 2.36 60 2.15
21 2.43 63 2.18
22 2.50 66 2.20
23 2.56 69 2.22
24 2.63 72 2.24
25 2.70 75 2.26
26 2.77 78 2.28
27 2.84 81 2.29
28 2.90 84 2.31
29 2.97 87 2.33
30 3.04 90 2.34
31 3.11 93 2.36
32 3.18 96 2.37
33 3.24 99 2.38
34 3.31 102 2.40
35 3.38 105 2.41
36 3.45 108 2.42
37 3.52 111 2.43
38 3.59 114 2.44
39 3.65 117 2.45
40 3.72 120 2.46

(I can't get the columns to display correctly. The first column is Primary turbo boost, second is Primary turbo PR, third is Secondary turbo boost, fourth is Secondary turbo PR)


Thus, if I'm wanting to run a total boost of 60 psi as measured by my gauge at the intake manifold, I want to wastegate the primary turbo to approximately 17 psi...since this is where the pressure ratios are equal.

If I went with conventional thinking, I would run 60 psi total, and 30 psi in the primary. However, doing so would put the primary at a PR of 3.04, which is more than likely well out of its highest efficiency range on the compressor map.

...and that's why Charles says to use a 35 psi gauge for the primary and a 100 for the secondary!


Comments?

--Eric



Exactly. Half and half is the easy way. Starting figuring PR's and its a different ball game. Charles is smart as fvck!

[ENafziger]

Exactly. Half and half is the easy way. Starting figuring PR's and its a different ball game.

I guess...but it seems like if you're going to resort to guessing rather than figuring, that 1/3 and 2/3 is a lot closer than 1/2 and 1/2?

[dmaxexpress]

well hopefully when these stand alone ecm come out they will have the data logger features nailed down as well. I would rather spend the 4K on that then acomplete datlogger system with all the extras for the same price.
I do agree that this is the true way for now


hey joelc79 ur from kent ohio im from ravenna and im going to put a set of twins on my 12v we should hang out some out.

[KoalRolr]

I did'nt realize it was this difficult to tune twins. I'm gonna run my super b over a s472 and from the sound of it i'll be trying to tune them for months! LOL

[bsmith]

I did'nt realize it was this difficult to tune twins. I'm gonna run my super b over a s472 and from the sound of it i'll be trying to tune them for months! LOL



I need to tune mine again, since changing the WG actuator. It sucks for me.

Even untuned they kick a singles azz.