Do you have the fuel to bump your rev limit? If you have the valvetrain and block build I think you do, you should be fine going to 8k. That'll get you to 65mph anyway, which will be a nice bump.

FWIW, my data shows that Sunday's course I only got over 55mph into the finish, and even then was basically doing 60ish through the finish lights. Saturday says the same thing. 55mph peak until the finish lights, which show at around 60-63ish depending on where the lights were exactly.

How do supercharger service intervals compare to a turbo?

I'd also like to note that even with like engine management, turbo cars have always produced more favorable results in my experience.

I don't know much about really long term service stuff. Change a few ounces of oil once in a while. In theory eventually bearings wear out and it needs rebuilding for a few hundred bucks, but I don't know the details about when that happens...

https://www.miataturbo.net/attachmen...1&d=1341281538


Hmm

For a road course, I'd take Bob's curve over mine any day of the week. For autox, I wouldn't. Autox is all about making the most of a series of 50 foot long acceleration zones, which are a fraction of a second each.

I used to have a street modified Alltrac with this:
https://www.miataturbo.net/attachmen...ine=1341282457

Sure makes a lot of torque. There were also many autocrosses where I _never hit full spool a single time_. Just because it says I make almost 400 ft/lbs at the wheels at 5000 RPMs doesn't mean that I ever actually saw that number hit the pavement. It was also fantastic on a track, with almost no lag (never below 4000 RPMs on a road course.)

When I exit a corner at 2800 RPMs and hit the gas, I have over 200 ft/lbs at the wheels, right then. If I stay floored for another 2 seconds, Bob's torque will catch up and hugely pass me. Look at a course like this, which was yesterday's NT course:

2012 Packwood National Tour Sunday SSM - YouTube

And count how many times I was floored for more than 1 second at a time but not traction limited (you'll hear it burbling when the traction control is limiting my power.) Every time I touch the gas that's not on your list, I'm gaining ground on Bob. Every one you count, he's started making ground on me, and if he stays floored for enough longer than that, he can make up the deficit he lost in the first second where I was accelerating faster.

Bob designed his car to be first and foremost a track lapper, and it's really good at that. As he's told me a dozen times, the car is a compromise car for autox.

Yea I only hit rev limit at the finish thanks to the Karen Babb course design. The thing is my torque falls off so dramatically at high rpm it almost feels like a rev limiter before you actually get there.

I think David he is right. We both got beat by a naturally aspirated Miata CSP and DP and the DP minimum weight is similar or more than us depending on displacement and wheel width the fast ones were running 10” wheels. Every time I heard David’s traction control hitting I knew I was losing time. In second gear even with 275 Hoosiers I cannot really use full throttle in a straight line especially since I believe I had too much rear camber. My car works better on a track and I can’t think of a track right now where I go lower than third gear for any corner.
Bob

Keep in mind DP's running Avon slicks (night and day over these DOT things we have to run, according to Jim and Keith,) and Jim Daniels' 1.6 Miata's min weight is MUCH lower than us. Only the NC is as heavy as us, and he gets hugely better suspension geometry, a much better chassis, and wider wheels/slicks than we do as well. DP definitely outhandles the crap out of us, we only get them on power. I'm not surprised at all that DP creamed us on that course. :)

Also, tangentially, you don't even bother downshifting to 2nd in 3a? :)

Jim has 1.8l running 15" Avons. Kieth had 1.6L 13" Avons. Ron had NC running 16" Hoosier. I know Rons minimum weight is over 2100 lbs.

Nope leve it in third. I run out of second coming out of 3b before I even get to track out. Second is kind of pointless as I get a better run through 4 up to 5 by staying in third. I've run 1:32.5 at Pacific on 225 NT-01's nearing 10 seconds under spec miata records.

Bob

Every turbo car I've tuned has a pretty manly driver who I'd like to hang out with.

Every supercharged car I've tuned had a driver who tried to barter bizzare sexual experiences or has a sex-swing in the trunk AND a tub of lube.

Peng-Robinson equation of state.

well fuсk, a torque plot I can't beat.

I like blowers. I love the whine, I love the instant power, I love way they feel. I hate the amount of work it normally takes to make silly amounts of power with them. I used to run this.

https://www.miataturbo.net/attachmen...ine=1341441273

Which was amazing until you realized it was only on 205 star specs, and would just roast the inside from tire if you even considered gently caressing the gas pedal mid corner. It was also on a car with a rear suspension thats main purpose was to keep the rear bumper off the ground and provide enough wheels to classify it as a car and not a motorcycle. I went into STR with the tired miata on worn out rs3s with a big front bar and otherwise stock and placed higher in pax than I had the whole previous year with that car. Not to mention that was the most power I was going to make on that car without head work, cams, and better internals with a compression bump from 9.5 to the planned 11.4. So glad I crashed that thing and saved a boat load of money.

But more back to this thread. I went to the m.net SC section and it made me want to kick puppies. The amount of stupid in there was painful, ------- Christ, rising rate regulators and boost-a-spark boxes are not acceptable engine management solutions .

Yeah, but the same problem exists with turbos. People use the Voodoo box like it's going out of style, and similar fuel/spark bandaids to attempt to not blow up their motors. In the age of 700$ functional engine management, those just make me sad...

Thats a good point. And it also seems that the 5th injector is making a comeback, what is this, the 90's?

I think the 5th injector has its uses (charge cooling), but not as people usually use them (bandaid injector to fix not having an EMS).

Theres a difference between running a 5th injector and running a 7 gph water/meth nozzle. Thats another thing that influenced my decision to choose the turbo for my car's movement to ssm, meth injection not being allowed in solo. Cause let me tell you, running an 14 gph nozzle with 50/50 water to meth would make a 2 litre blower make some serious power at 20something psi on a bp without doing silly amounts of head work (e85 included).

I agree -- the disallowing of meth injection in solo is infuriating.

I'm considering trying doing an alternate version of my current build (but using the newer W100AX) on a 1.6 motor, non-intercooled, with using an E85 5th injector for most of the cooling, or potentially with some water as well (or entirely instead of the 5th injector).

I'd run straight water pre-blower, and then e98/85 in just another water/meth and consider doing e98/85 in the normal fuel injectors but give them as much runner distance to the head as possible. Tuning would be a complete nightmare, but that would get you the best charge cooling. And e98 would be preferable over e85, course straight meth for fueling would be even better but obviously not allowed.

so a question for you gentlemen and something ive been thinking a whole lot myself.

so it seems that most everyone here is for the turbo charger and a few others defend the super charger but here is my situation that ive been thinking alot about recently:

so i want a forced induction system on my miata (1990) i love the handling of the car but when you are getting past by minivans, its time for more power so recently i have found the greatest road known to man :p i am not a dragster kind of guy, i love turns, and i love corners. and my favorite past time is to take my miata to the mountain roads near my home and just take those corners as fast as possible. upon driving this amazing road i have found it dawned on me... if i was to have a turbo charger, being a guy of limited driving skill, i dont think i would be able to handle the power, sorry, the sudden onset of power that the turbo would create. because turbo's work off of the exhaust gases as we know, there is a certain amount of lag before a turbo spins fast enough to create positive displacement, know no matter how quick or low in the rpm range this response happens, it is still there, which means when power sets in, it surges in, and if i am taking a corner, the last thing i need is a surge of power to offset the balance of the car.

so in my opinion, i think most people who purchase a super charger are looking for what im looking for, power that is instant, and more important, linear. we may not be worried about overall power (at least in my opinion) but rather the knowledge that my power isn't going to be all over the place when i mash the gas.


well sorry for the speech i just wanted to give that point of view, thanks for listening