Jack Sprat

Thanks! Got some work to do but it was a blast.

Jack Sprat

After reviewing the play, the player did not go out of bounds. The penalty is declined. LOL

It ran a 13.1 @ 105. It was a decent start but with gearing and a good carb it would hit low 12s maybe even high 11s. Mid 12s should be minor tweaks and harder launch since my 60' times were 1.9 - 2.1.

charchri4

Sweet! That's gotta feel good and coming home healthy is a win for sure. Congratulations on a great run!

So what are you thinking is the sweet spot for the gears between street and track? 3.73s or so?

Jack Sprat

Thanks! I was expecting it to be unsettled due to the short wheel base but it went straight as an arrow. My plan to build the front subframe while bolted to the car worked really well since I didn't have to align the wheels.

I ran the numbers for rpm vs speed and here is what I came up with for the rear gearing:
gears__3.27____3.73____4.11
rpm__6750____6750___6750
1st ____42______37_____34
2nd ____71_____62_____56
3rd ___106_____93_____84
4th____141____124____112
5th____208____182____165

In drag racing, ideally you cross the finish line at your max power in 4th gear since this will give you the greatest torque multiplication throughout the run which is especially important to get off the line (best 60' time). I am currently crossing at 105 mph in 3rd but the car is paying a huge penalty throughout the entire run just to save 1 gear change.

The 3.73s are really good in that I can stay in 2nd up to 62 but it is doubtful that I will hit 124 in 4th with the present hp amount. They will be ideal if I add nitrous later (which I am planning).

With the 4.11s, the small displacement engine will spin up quickly and run out 1st and 2nd in no time requiring me to be on point with my shifting. It will be amazing off the line if I can get the car to hook given the incredible torque being delivered to the wheels (4819 ft lb - twice the weight of the car) at max power.

All told, I think the 3.73s are best but a friend is gonna give me some 4.11s once he pulls them - so 4.11s it is. Not trying to be a wise cracker, I did the comparison so that it may help others see how important your rear gears are to performance. Bad thing is that I'm going to be giving up on the 200+ mph runs.

Jack Sprat

After many months of work, today the V8 Miata shined! Sure it has super crappy stock brakes and no sway bars but with the proper driver (not me) it was able to run within a few seconds of the best time of the day- HECK YEAH! Not bad for its first race weekend.

Thanks for everyone's support and the tons answered questions.

You guys are awesome.

MX-Brad

Wow, tricky course. Good run. Sounds great.

577nitro

Outstanding!!

charchri4

Wow that baby sounds great! Really fast hands in your driving there and great catch on what could have been disaster at .46 with the tail happiness.

Looks like you have done this before because I'm not seeing the usual newbee mistakes and you are not holding back. So what do you think more fun than going straight?

ToySnakePMC

Congrats! Your little dragon slayer sounds fantastic. Enjoyed the video ride-along too!!

Jack Sprat

Thanks Mx-Brad, 577Nitro, CharCri4, & ToySnakePMC

Jack Sprat

The funniest comment was that a guy said he kept hearing a nasty sounding V8 and looked out on the track only to see my little white Miata. Laughing he said "That is SOOO wrong!"

I wish I could claim the fast handing in the video. It was my driver mod (Zach Williams), stepping in to show me how to drive. He drove it almost 6 seconds fast than I could. I'm still holding back, Jim. lol

charchri4

LOL Brother I hear you! My very first ever autocross (for my 50th birthday gift) the guy they assigned to ride with me and help me get going had never driven a Camaro before and took 5 seconds off my best time. I found it very humbling and eye opening to the value of the driver!

I hope this is the first of may autocross reports from you!

Jack Sprat

I totally understand. I started out at 75 seconds, then 72 and finally back to back 69s. His single run driving my car was over 6 seconds faster. I really feel that the car left the ground on the hump in the middle of that long sweeper. So much of it is about the driver unlike drag racing which is 90 percent car/tires.

The best thing is that I made a lot of new friends who I hung out with after the race as well.
I'll be posting more. Might have to post my blooper video.

Jack Sprat

Okay, I decided to go ahead and post it. I spun out twice in the two days and I did this:

charchri4

LOL I love it! So great to hear you laughing and having fun! That's what it's all about. Don't sweat looping it. That is exactly how you find where the limit is and learn car control.

I'm really proud of you Jack for going out and going for it!!! WELL DONE!

Jack Sprat

I took the Miata back to try the 99 brake swap that I had installed. I didn't put new pads on it because they appeared to be in good condition. The video below was taken on the short (slow) novice course:


It shows what happens when you have too much go and not enough whoah. You are supposed to stop at the STOP sign, but I couldn't. I have since upgraded to some Hawk HP Plus (black box) pads on the front and the difference is phenomenal - when you hit the brakes hard, it now feels like your face wants to leave your head. lol

I'm still a novice but my setup seems to be working great. Next race, I will be able to push the car really hard and bleed off speed prior to turn vs relying on engine braking so much.

If anyone is interested, I will post my suspension setup or anything else that someone may want to know about my conversion.

577nitro

NICE!. sorta like a "live" update. Hawks are supposed to be quite good. Did you brake them in, or just go full bananas?

Jack Sprat

I used a DA sander to take the glazing off the rotors. I broke the brakes in according to the manufacturer's recommendations which is very easy and only takes about 20 minutes.

I haven't taken the car back to the track yet but the brakes are amazing on the highway.

577nitro

Good deal, that's a good process....works on old flywheels, and new clutch disc too

Jack Sprat

I'm prepping the car for my first HPDE this weekend. This is the first time I have been nervous about a race because it has a 1/2 mile straight-away and I'm not much into lifting. I expect to be in the 150-170 mph range which would be scary in a go kart sized car.

Anyone ever done this?

MRM331

Things get a little scary in a Miata over 140 without some serious aero work. I hit 133 I think at one point during the above event.

Have a great time and post move video!

-Jason

Jack Sprat

That is an awesome video. Love the video/track/ecu software. Is it megasquirt?

Yeah, I've been 110 at the track and it's very stable but I think it may get a little dicey at 130-140. I'm not catholic but I'm thinking about borrowing a St. Christophers for this weekend.

MRM331

It's running on a MS2 which streams telemetry through a bluetooth connection to my phone. The phone is running Shadow Dash and also connected to a bluetooth remote GPS antenna on the dash to get accurate MPH and track position readings. Once I download the data log for each run I drop it and the GoPro video into Race Render, sync them and get the above. It sounds complicated but its really not. The hardest part was getting the exhaust sound to be "enough". After trying different recording positions and even considering a remote mic I finally just installed a 1" diameter bung in each pipe in front of each muffler.

Again, have fun!

-Jason

Jack Sprat

Had an awesome time. With the exception of some overheating issues, the car performed amazingly. In fact, the car is much better than I am willing (yet) to drive it. With that said, I came in 3rd in my division.



Here is the video of my first (slowest) run. I had an instructor with me but they turned me loose after that run. Unfortunately, the battery died in the camcorder so I didn't get any videos of later runs. If you go full-screen you can see the speed on the GPS mounted to the windshield. I typically hit 70 in the last curve and topped out at 117 at the timing cones. The Hawk HP plus brake pads were really good.


I have successfully crossed off one bucket-list item and had a great time doing it.

MRM331

Very nice! Sounds good too.

-Jason