Power vs Aero on Miata

[turbogrill]

Hi,

I noticed that many fast NC Miatas are running full aero instead of header due to points.

Header is supposed to give you 10-15whp, ending up with  close to 160whp on a good day. 

Thoughts?

[55mini]

I would say that will be track dependant. A track like Road America the power would be somewhat of a help and don't know the header but if power is not 

broad band improvement it might not help much, peak HP is just that.

 

Aero would offer a more predictable result over the wide range of speed and provide more stability to driving.

 

 

[mindspin311]

Can you get similar gains by improving the stock manifold in some way?

[turbogrill]

1 hour ago, mindspin311 said:

Can you get similar gains by improving the stock manifold in some way?

 

Aha Good point! No one in the Miata community does so haven't heard about it.

Maybe they port it and loose a 5hp or so...

 

 

[JDChristianson]

12 minutes ago, turbogrill said:

 

Aha Good point! No one in the Miata community does so haven't heard about it.

Maybe they port it and loose a 5hp or so...

 

 

One hard thing is that no one in the Miata community is working to Champcar rules.  For the most part, info that is readily available is "how to make power with a Miata" and most answers are Swap, Turbo, Supercharge, or all of the above.     With Champ rules of no min weight, and an assumption of not wanting to run the car in other series I would guess that cutting the bageebers out of the car and doing the free porting and aftermarket ECU for tuning is the best way to HP to weight gains and running aero makes the car more stable and faster in the corners.  

[turbogrill]

Just now, JDChristianson said:

One hard thing is that no one in the Miata community is working to Champcar rules.  For the most part, info that is readily available is "how to make power with a Miata" and most answers are Swap, Turbo, Supercharge, or all of the above.     With Champ rules of no min weight, and an assumption of not wanting to run the car in other series I would guess that cutting the bageebers out of the car and doing the free porting and aftermarket ECU for tuning is the best way to HP to weight gains and running aero makes the car more stable and faster in the corners.  

 

haha yes, they think I am an idiot in the Miata forums. 


 

[JDChristianson]

30 minutes ago, turbogrill said:

 

haha yes, they think I am an idiot in the Miata forums. 


 

yep been there,  try to find out good info on building an non forced induction engine and mostly what you get is  "get a Turbo its more bang for the buck, my buddy makes 1000hp with an ebay kit" 

 

Edited November 22, 2022 by JDChristianson

[turbogrill]

13 minutes ago, JDChristianson said:

yep been there,  try to find out good info on building an non forced induction engine and mostly what you get is  "get a Turbo its more bang for the buck, my buddy makes 1000hp with an ebay kit" 

 

 

Or "just buy a set of $1500 entry level coilovers" 

Weeell, I would love to but...

 

[MMiskoe]

2 hours ago, JDChristianson said:

One hard thing is that no one in the Miata community is working to Champcar rules.  For the most part, info that is readily available is "how to make power with a Miata" and most answers are Swap, Turbo, Supercharge, or all of the above.     With Champ rules of no min weight, and an assumption of not wanting to run the car in other series I would guess that cutting the bageebers out of the car and doing the free porting and aftermarket ECU for tuning is the best way to HP to weight gains and running aero makes the car more stable and faster in the corners.  

Yeah.  What he said.

 

 

Sorry, I wrote all this up then saw you're asking about NC cars, not NA/NB's.  But I'll post it anyway, its already typed, it kind of relates.  I know nothing of NC's.

 

 

I've asked one of the well known Miata engine builders about Champ motors and he said he'd played a bit with one or two motors for cars being used for track toys, similar efforts.  And yes, cams, porting, compression bumps all help.  But no one is developing them like they are for Spec Miata or STL. 

 

I'm pretty sure a header alone is not giving you 15HP.  You'd need both of the stickers it comes with to get there, you know their worth 5HP each.

 

 

As an owner of a pretty aero'd up Miata (NA), all I can say is that it is a science experiment.  Is the car faster with the aero, yes.  By how much?  I don't know.  Could we better spend those points on cams and fender flares?  Maybe.  Does the Aero make a difference - oh hell yes.  But boy, is it hard to quantify.  I put mine on Hoosiers for a race - cripus it was hard to drive because the hoosiers want slip angle, the aero doesn't.  Run it too high and the supension doesn't work.  Run it too low (or too close to someone) and the aero stalls.

 

 

[chbright]

@Grant can the nc run the 245 on 17s without coilovers? Cause the coilever swap on NA/NB is about tire/rim clearance to run 245s.

 

If you can run standard diameter coils and 245 on an NC, then power and aero is the way correct?

[turbogrill]

We run 255s on 17s, need a slight spacer to not hit the large OEM sized springs. Our car also sits quite high but don't want to cut more since it's already quite stiff (70% of spec mx5 but stock sway). We are using springs from a 80s Ford that happens to be exact same size as a Miata spring but longer.

Adding a wing to our setup might not be the best since it's difficult for us to adjust things? But we already have our header and power is easy

We are about 1-1.5s slower than the fast NCs with aero on a track with no straights (Harris Hill).

(That 1s could very much be driver skill but obviously not. It's always the car, not the driver).

 

[Chappy]

All things equal, I would say aero will be more benefit than hp from a header (unless the stock exhaust manifold is a huge restriction, which it shouldn’t really be based off the other ChampCar rules).  I’m an NA aero car, while not 100% easy to quantify, I’ll say since adding aero all drivers have consistently dropped over 1 sec a lap for bests for the day.  We wouldn’t see those gains with 5hp from a header.  
 

In reality, the answer is more based on how the people driving the car drive.  I’m betting most teams don’t have all drivers consistently lapping within 0.5 sec of each other.  So what mod will give the slower/less consistent drivers the biggest bump in performance?  If a driver isn’t as confident in traffic/passing it might be more beneficial for hp to make the passes easier on the straights.  If they don’t have confidence in high speed corners, maybe aero would help add confidence.    
 

At the end of the day, best lap times of the day are great for bragging rights, but what wins is lowest average lap time over the day.  I’ve had drivers in my car before that would put down 1-2 hero laps to get quickest of the day, but put them in traffic and they get passed by everyone.  That is a person that likely won’t win you races.  Aero or header won’t make a difference with them probably.  

Edited November 30, 2022 by Chappy

[Wheelman_99 - C Rallo]

A few factors...

 

Wing and splitter are likely the cheapest speed any car can buy, by how much at least partly track/application dependent and don't forget, a header would still be another 5 pts.

 

Aero speed is more fuel efficient than hp speed.

 

All the handling in the world gets you fast clean laps, but in traffic and racing an equal lap time car, power pays off better.

 

 

[Special K]

Try cheating. They can't catch EVERYTHING you do

 

 

 

 

I mean, read the rules to your advantage. Then you can do all kinds of stuff

Edited December 7, 2022 by Special K

[MMiskoe]

19 hours ago, Special K said:

Try cheating. They can't catch EVERYTHING you do

 

Reminds me of a dinner table conversation where one of my kids who was about 14 at the time said "cheating is a strategy".

 

I just shook my head and wondered where I gone wrong as a parent.

[CoachMK21]

It's one of those sayings that has just stuck, "If you ain't cheating, you ain't trying." To go along with "Rubbin' is Racin'". Unfortunately, the semi-serious of both of those has been taking as a rule by many.

[petawawarace]

On 12/6/2022 at 1:30 AM, Wheelman_99 - C Rallo said:

A few factors...

 

Wing and splitter are likely the cheapest speed any car can buy, by how much at least partly track/application dependent and don't forget, a header would still be another 5 pts.

 

Aero speed is more fuel efficient than hp speed.

 

All the handling in the world gets you fast clean laps, but in traffic and racing an equal lap time car, power pays off better.

 

 

Power is also a lot easier for drivers of all skill levels to take advantage of.  Slower drivers are generally not taking advantage of the corner speed and maximum grip. But they easily press the pedal down just the same.   

[turbogrill]

13 hours ago, petawawarace said:

Power is also a lot easier for drivers of all skill levels to take advantage of.  Slower drivers are generally not taking advantage of the corner speed and maximum grip. But they easily press the pedal down just the same.   

Very true for us 2s difference between drivers sometimes 

[veris]

17 hours ago, petawawarace said:

Power is also a lot easier for drivers of all skill levels to take advantage of.  Slower drivers are generally not taking advantage of the corner speed and maximum grip. But they easily press the pedal down just the same.   

That is a fair comment. 

 

It is track and setup dependent, but I've found aero has actually closed the gap between drivers. Specifically with confidence in high speed corners. The delta between drivers has become smaller in my car. Could be a lot of factors including more experience, but none of my drivers are inexperienced. 

 

For me it has also made a hot lap more accessible/repeatable. 

Edited December 9, 2022 by veris

[mender]

17 hours ago, petawawarace said:

Power is also a lot easier for drivers of all skill levels to take advantage of.  Slower drivers are generally not taking advantage of the corner speed and maximum grip. But they easily press the pedal down just the same.   

One of my co-drivers had a hard time passing a car on the straight during his stint. I had no trouble with the same car. No change in the power level of either car, the only difference was the drivers.

 

The videos showed that he was aggressive coming into the corner, I was aggressive coming out. Last summer at a test day while using the AIM Solo as a lap timer and a fast lap by me as the baseline, he finally clued in and dropped two seconds over two sessions and got within one second of my times. I've been telling him this for ten years but until he could see where he was losing time he didn't change what he was doing.

 

The data showed that peak g forces under braking, cornering, and accelerating were all very close but the peak and minimum speeds weren't. He was using the car just as hard if not harder but was fast in and slow out.

 

P.S. He's convinced that our car can outbrake any car out there (it can't), and he's had numerous incidents while "proving" that.

Edited December 9, 2022 by mender

[jakks]

2 minutes ago, mender said:

One of my co-drivers had a hard time passing a car on the straight during his stint. I had no trouble with the same car. No change in the power level of either car, the only difference was the drivers.

 

The videos showed that he was aggressive coming into the corner, I was aggressive coming out. Last summer at a test day while using the AIM Solo as a lap timer and a fast lap by me as the baseline, he finally clued in and dropped two seconds over two sessions and got within one second of my times. I've been telling him this for ten years but until he could see where he was losing time he didn't change what he was doing.

 

The data showed that peak g forces under braking, cornering, and accelerating were all very close but the peak and minimum speeds weren't. He was using the car just as hard if not harder but was fast in and slow out.

You mean that saying, “slow in, fast out” is possibly true?

[mender]

33 minutes ago, jakks said:

You mean that saying, “slow in, fast out” is possibly true?

I think most people know this but what the heck, let's jump in.

 

My co-driver and I started in autocross. We noticed each other because we were the fast guys and started talking. The friendship had started and is still very strong today, forty+ years later. I did the Jim Russell school at Riverside (FF) and the grad runoffs in 1982. That gave me a different perspective on how to achieve lap times because of the long straights. I also drove V8 RWD cars while my co-driver mostly drove 4 cylinder FWD cars in the autocross events, so our beginning years had different approaches but similar results.   

 

Our next step was on the local 1/2 mile banked and paved oval. Still not much for straights, still both of us winning races in our own style. I braked a little earlier and settled the car then got back to throttle earlier. He did the opposite, braking harder and driving into the corner deeper. It showed when we ran together in even cars: he would gain on me into the corner and I would gain on him down the straight. He would pull ahead by half a car into the corner, then I would be half a car ahead by the next corner, so swapping about a car length total back and forth for lap after lap. In a 20 second lap, about 6 seconds was spent on each end of the track and about 4 seconds on the straight. So imagine what would have happened if suddenly the straight continued on for another 10 seconds. That car length advantage that I gained on the straight would now be about a three car length advantage by the time we got to the next corner. 

 

And so it happened on the road course. The longer straights were clearly an advantage for me despite having evenly matched cars. He was fast in but couldn't get to the throttle as early so was slow out. I was slower in but got on the throttle early and was fast out. On a track or sequence of corners with short straights, we were even, and sometimes he would have the advantage. On a track with longer straights and fast corners, I had the advantage. The longer the straights, the more time I made on him, typically about 3 seconds on a 2 mile track. 

 

Alan Johnson was the first person to write about Type I, II, and III corners and why they should be driven differently. That was about fifty years ago IIRC and although there has been much discussion and refinement, I think the basic principles still apply. Fast out onto a long straight, fast in after a long straight, lose as little speed as possible through combinations.  

 

So "slow in, fast out" in a Type I corner is faster than "fast in, slow out". But the fastest of course is "fast in, fast out".

Edited December 9, 2022 by mender

[DEE DEE]

Mender I drove a Formula Atlantic and learned fast/slow, entry/exit really quick.  Every type of corner should be Identified and broken down at each track.   I learned from Jim Russell & Bondurant schools also friends with Michael Andretti when he ran Formula fords in scca.  I picked up a few things from his teacher

[mender]

I crossed paths with Jim Hall II back in the day, shared the track with Greg Moore in FF and later met Jacque Villeneuve when crewing on a NASCAR team. Small world.

Edited December 9, 2022 by mender

[Team Tbird]

“A driver wants to enter the turn like a gentleman and exit like an animal!!!

 

Sir Sterling Moss.
 

 

 

1 hour ago, DEE DEE said:

Mender I drove a Formula Atlantic and learned fast/slow, entry/exit really quick.  Every type of corner should be Identified and broken down at each track.   I learned from Jim Russell & Bondurant schools also friends with Michael Andretti when he ran Formula fords in scca.  I picked up a few things from his teacher

 

4 hours ago, mender said:

One of my co-drivers had a hard time passing a car on the straight during his stint. I had no trouble with the same car. No change in the power level of either car, the only difference was the drivers.

 

The videos showed that he was aggressive coming into the corner, I was aggressive coming out. Last summer at a test day while using the AIM Solo as a lap timer and a fast lap by me as the baseline, he finally clued in and dropped two seconds over two sessions and got within one second of my times. I've been telling him this for ten years but until he could see where he was losing time he didn't change what he was doing.

 

The data showed that peak g forces under braking, cornering, and accelerating were all very close but the peak and minimum speeds weren't. He was using the car just as hard if not harder but was fast in and slow out.

 

P.S. He's convinced that our car can outbrake any car out there (it can't), and he's had numerous incidents while "proving" that.