15 replies to this topic

[Brian129]

So after race school at Roebling, I had a trackday at Atlanta Motorsports Park.

I had been there before, running my traqmate, but that was before my recent rebuild.
I swapped motors, it is now a Race engineering motor (was a stock 124k mile), with a more open exhaust.
I am running more camber, I have lightened the car 60 lbs, and put Hoosiers on (coming from RA1's). I was expecting to be DRASTICALLY Faster!! I was not.

I know I suck, hence why I was at the trackday trying to work on speed.
So with that said, I ran a 1:42 last time there, and managed a 1:39.9 this time.
I was hoping I could find some traqmate data to get a better feeling on how I can improve.

I was running with another ITA miata that is minorly prepped.
I was pushing hard, and could not run him down, he had more on the straights, most would say oh he got on the gas sooner. He was pulling out more later on the straight. He has a 157k stock motor on stock exhaust.

So looking at the data, I notice that the acceleration graph shows a dip in accel compared to my stock motor. In reviewing it, I am seeing accel will still hit max momentarily, before dropping.
I had set timing in the morning, 14 degrees. The FP reg. is set to stock pressure to get the car past emissions last year. I'm stumped what could cause it to loose HP, but only at WOT.
Blue lines are from this past sunday, with the new updates to the car, redlines are from last year on the old engine.
https://www.dropbox....at WOT.tqs?dl=0


So you don't have to pull the traqmate data. See the dip where the cursor is, that's what I am talking about. On the blue line. The motor should be faster than the red line.

looking for someone with more experience in data logging, am I correctly assuming my accel difference here?
any suggestions on where to start? I'm thinking it is more electrical, the motor has 1 race school on it.
anyone that's quicker than I am (that shouldn't be hard) mind sharing some traqmate data? The only one I can find online is not a full lap.

[Brian129]

one thing I am thinking, would it be from just going lean?enough to show that power loss from just going lean?

 

Its a stock 1990 pump,  though the car seems to run great.

I have been thinking about putting a wideband in me driver side eyeball vent to the left of the wheel. that way I can keep an eye on if I have the car close on tuning.  

[Johnny D]

So I'm not an expert but I don't think you suck, just learning. You don't know what you don't know.
With the engine... get it tuned, if you're running lean, you're going to blow it up.
As for going from RA1 to Hoosiers is a big increase in grip, possibly different setup and driving style assuming your driving at the limit of the car.

If you're learning the limits of the car, the track, and trying to be consistent lap after lap, you don't really need the Hoosies right now, just track time.

Don't drive tired, you learn bad things, rest, review what you've done and go out to learn and improve.

J~

[Brian129]

1:34's is a decent time. I expected more from myself.

I'm not sure it's lean, I will check it, but I'm just trying to think why would it go soft on power at Wot.
I know the tps sensor on a 1.6 is a closed and wot 2 position switch basically. To tell the ecm when it is not trying to idle, and when you are at full throttle. Could it be picking up full throttle and causing some kind of ignition cut?
It has a stock airflow meter, I have seen comments that they are restrictive, but by this much?


I put the Hoosiers on to try driving with the increase in grip. I started the morning on old RA1's. (06 build date), just wanted to get a little seat time on the Hoosiers (I have a set of sm7's with about 10 heat cycles now) I know I was making one fundamental mistake. I knew I was slower than I wanted to be, so I was pushing past limits a lot, and you can see the results in very jumpy data on corner exit.
I should have pulled back some and smoothed myself back out and then tried to make another push for speed. I have the car setup with a lot of camber right now, so it is really important to make a smooth corner entry to load the tire properly.

[James York]

Brian,

 

I am not a data expert by any means, but I wouldn't use longitudal g's to try to measure any differences in engines.  But a couple of comments.  First, Hoosiers are heavier and have more rolling resistance than RA-1, so "effective" acceleration will appear less.  I would use trap speeds to see if there was any difference between your two motors, but again, this is very subject to tire, weather, etc being months apart.  That dip you are point out might just be bad data spike.  I believe your bottom graph is the speed traces and looking at them, the lines look similar. 

 

It's possible any gains in motor power were offset by the heavier tire.  (or weather..)  

 

If you don't have the time/skills, I would take your car to a SM shop and:  1)  Get an AFR installed, 2) Tune the AFM and/or add FPR and 3) dyno the engine to really see what you got. 

 

You'll sleep better just knowing what you have and know its right.  Then you just work on driving.

[Todd Lamb]

This is a perfect example of too much data, and not knowing what to do with it. You're headed down the wrong path....

 

These cars don't have enough HP to use the accel/braking G for acceleration. You should be looking at the slope of the velocity trace (straightline accel the best) to compare.

 

Also, I notice your LatG's for some reason are skewed for left handers (up) with the blue laps, making your left hand max artificially higher and your right hand max the same as the red. This tells me you bumped/moved your traqmate, so I would also conclude that the accel/braking G is also likely skewed. Is your traqmate mounted firmly and/or did you move it?

[Keith Williamson]

Brian,

Not sure if it is a typo or I've just miss read your post.  You say 1:34 is a good time and you expected more from yourself.  If you did that at AMP you're doing great.  The SM track record set by a 99 is 1:33.6. 

[Brian129]

 

Brian,

 

I am not a data expert by any means, but I wouldn't use longitudal g's to try to measure any differences in engines.  But a couple of comments.  First, Hoosiers are heavier and have more rolling resistance than RA-1, so "effective" acceleration will appear less.  I would use trap speeds to see if there was any difference between your two motors, but again, this is very subject to tire, weather, etc being months apart.  That dip you are point out might just be bad data spike.  I believe your bottom graph is the speed traces and looking at them, the lines look similar. 

 

It's possible any gains in motor power were offset by the heavier tire.  (or weather..)  

 

If you don't have the time/skills, I would take your car to a SM shop and:  1)  Get an AFR installed, 2) Tune the AFM and/or add FPR and 3) dyno the engine to really see what you got. 

 

You'll sleep better just knowing what you have and know its right.  Then you just work on driving.

 

 

I do plan to tune the car on a dyno very soon,  this was a push getting to school and this event,  I have sometime for the next one.  

I forgot about the weight and gearing difference with the hoosiers. thanks,

 

 

This is a perfect example of too much data, and not knowing what to do with it. You're headed down the wrong path....

 

These cars don't have enough HP to use the accel/braking G for acceleration. You should be looking at the slope of the velocity trace (straightline accel the best) to compare.

 

Also, I notice your LatG's for some reason are skewed for left handers (up) with the blue laps, making your left hand max artificially higher and your right hand max the same as the red. This tells me you bumped/moved your traqmate, so I would also conclude that the accel/braking G is also likely skewed. Is your traqmate mounted firmly and/or did you move it?

 

I will be the first to admit I do not really know what I am doing with all the data i get from the traqmate. 

So based on the velocity trace from the two its probably not something I should worry about,  that is probably just the difference in tires? 

 

I did have the traqmate out,  the sensor box is mounted in my center console, on the heavy duty solid plastic velcro stuff.  

the top one that is cut off is Lat G,  you would say that is shifted?  I do see the blue over the red in most places. 

 

 

Brian,

Not sure if it is a typo or I've just miss read your post.  You say 1:34 is a good time and you expected more from yourself.  If you did that at AMP you're doing great.  The SM track record set by a 99 is 1:33.6. 

I say a 1:34 is a good time,  but my time is coming from a 1:42 to a 1:39.9 

my goal was 1:38, aiming for 1:38.0.  hence my disappointment, I will return to my corner with my head down now. 

the only good thing was this is the first time I did not break the car

[James York]

If you just started and you are just 5 seconds back from a good SM time, I would say you are doing fine.  Just need seat time.  You may be expecting too much too soon.

[Keith Williamson]

I agree with James, if you just started, a 1:39 is a good time, especially for a 1.6.  If you want to pm me I'd be happy to meet you at the track and share what ever I can on picking up some pace at AMP.  We have an SM race there each month and that would be a good time to meet some of the other SM guys.   Everyone there is pretty open and helpful with info.

[Keith Williamson]

Brian,

Just re-read what I wrote and it may sound like I was putting the 1.6 down when I said 'especially for a 1.6".  I think the 1.6 is harder to drive .....especially at AMP.  To get a good time there in the 1.6 you have to keep the engine RPM up and that means getting into 2nd gear and having to shift mid corner in a couple places (the carousel and 13).  Glen from Traqmate is very fast in his 1.6 and he has quite a few videos on the traqmate site.  He has the gear number, RPM and speed in the video and that can give you an idea of his corner speeds etc.

[Brian129]

I do expect a lot from myself,  but I am coming from a background of motorcycle racing, and I have driven this car almost all of last year at these local tracks. 
maybe i am pushing a little too hard on myself. 
 
Keith,  I do plan to try to make it out to one of the member races,  I have heard you don't specifically have to be a member to race.  
though I need to cut some more time first.  
I understand what you mean about the 1.6,  I wanted it to be a challenge, and for it to teach me to be able to drive the wheels off the car.  
I just was anticipating more improvement.  
 
video from the end of the day, cashing the other miata I spoke of
 
https://www.youtube....bed/CNRkgDNuLQ4

 

[Johnny D]

Have you watched all these??
https://www.youtube....h?v=65COxg47K1U
J~

[Todd Lamb]

From the velocity curve I don't see a HP problem. You mentioned going to the dyno - that's the proper way to check HP and air/fuel. Anything else is just speculation.

 

Yes LatG's appear to be shifted "up" to me, which is why I asked if you moved your traqmate. Traqmate doesn't zero out so any change in the position will affect all of your G forces.

 

 

 

 

I will be the first to admit I do not really know what I am doing with all the data i get from the traqmate. 

So based on the velocity trace from the two its probably not something I should worry about,  that is probably just the difference in tires? 

 

I did have the traqmate out,  the sensor box is mounted in my center console, on the heavy duty solid plastic velcro stuff.  

the top one that is cut off is Lat G,  you would say that is shifted?  I do see the blue over the red in most places. 

 

 

[Keith Williamson]

It's hard to get a good time with the cars you are following.  Almost none of them are going to go thru turns 10 and 11 at the speed you need to go in the Miata to get good times. 

Randy's video is great.  I like Glen's  with his displays:

 

 

Non members can race in the series at AMP but are required to have a Comp. Lic.

[RussMcB]

Brian,

 

I think Glenn's data is posted on the TraqMate web site, available for download and comparison.

 

You're welcome to my data, but Glenn's is probably better.  He has a 1,000 miles at that track (I'd guess).  I couldn't come close to his time.  My best lap last time there was a 1:37 with a passenger.