I'm still in the planning phase of my LS swap project and I would like to hear your impressions on how your car handles at high speeds. My plans are to spend 75% of my driving time cursing on public roads, obeying the posted speed limits (within reason ) but 25% of the time I'll be participation in HPDE. Until recently my fun car was a C5 Corvette and it was not uncommon to exceed 130 mph at the track day events. I never had any concerns driving at those speeds and the vette handled the speed well, as it was designed to do. For those of you that have taken your V8Miata's to speeds exceeding 100 mph what are impressions on the stability and handling. By the way what is the max speed on a stock Miata?

Thanks

 

Not even a though about stability until deep into 5th. (T56 & 3.42 final)

 

A stock NB and a couple miles of open road will run out of gear just shy of 130, iirc.

I've had mine up around 140 (top of 4th) a few times and the car feels stable. I don't have any aero, so I'm not too confident about what it would do over the 150 range. I wouldn't mind trying a standing 1/2 mile (130 in the 1/4) or full mile at some point, but not if the car will do summersaults at speed.

I'd love to hear some other experiences and levels off prep.

 

It's very comfortable at 100 and I'm lucky to live in an area I can set the cruse control at 100 on the way to work for about 5 miles and not worry to much about things.

It's hard to see here but the road bends around that hill and the car takes it beautifully.


I have to tap the brake here and drop her to about 80.


So anyway I'm on Spec Miata suspension with FM V8 bars and it feels very good to about 120 or so. Beyond that things get more intense. At 140 the car itself starts to feel a little light but the driver gets pretty shaky up there. Things happen real fast at that speed and don't have the training or experience to feel comfortable there at all.

140 is the top of 4th in mine too and never had a desire to shift to 5th. I have no doubt about 160+ out of the car but it's not going to happen with me in it!

 

Thanks for the replies, it looks like 130 is doable. When I tracked my C5 I could leave the "Toy" cars behind in the straight away but they would keep showing up in my rear-view (and pass me ) in the curvy parts of the track. I've never driven an MX5 but I'm hoping a V8 powered Miata will be the best of both worlds. Quick in the corners and fast on the straights.

 

Just install in the driver mod along with the V8.

 

The slowest part of my car is differently the Driver

 

It is but Gator is right and I see it all the time at autocrosses. A good driver in a bad car will beat a bad driver in a well prepped car any day. I had a friend of mine drive my car in a fun run who is 8 year veteran auto crossing an NA Miata but never driven a V8 Miata in his life. After 2 trips around the course he was .8 faster than by best time of the day and I have no doubt with another few laps would have doubled that.

There is really no such thing as motorsports because the car doesn't win races the driver does.

 

Here's a vid from the last time I had it on the track at Pocono:


I can see that the Corvette guys are a lot more confident doing over 130 on the banking. While the car was very stable on the straight a ways over 120 and even up to 132 (highest I hit that day) I felt I had to drop it down quite a bit to keep it from pulling out from under me at that speed on the banking. Keep in mind this could be do to any number of factors, not the least of which is my confidence level at that point. I'm seriously thinking of adding a real splitter to the front before I try that track again. Right now it only has a GV knock-off splitter on it.

-Jason

 

You know I have watched with great interest, enthusiasm and envy all of your track videos and the same thing always strikes me. You are very controlled, smooth and careful out there and I always feel like you are going about 7/10s of both the driver and the car. Granted Pocono is not the safest place in the world to find the limits and it's certainly understandable to take it easy next to a wall but I'm not so sure the confidence of the vette guys is any indication that your car is less capable.

 

I'm pretty sure that without transmission mods my top speed at that track in that configuration is not going to eclipse 135 or so. I do agree that my head is limiting my speed somewhat but I think when I go back this fall with a few of the "troublesome" areas of the car upgraded I'll be more willing to squeeze a few more tenths out of it. Thanks though.

 

That day posted above actually used up what little was left of my ring and pinion and ended up snapping a steel rocker arm in half on me. This fall I'll be back with a fully built rear diff with all new parts (only the case will be kept), AFR heads with Scorpion Stud mounted rockers and a few more upgrades that will boost my confidence in my ability to drive the car back home after flogging it.

-Jason

 

LOL yeah there is the whole drive the car back home thing! And the not wanting to be "that guy" that shuts the run group down to get dragged out of the weeds...

 

But I trailer it in... so all good!