Half agree. 94-00 motors have a defined torque peak at 4800rpm. VVT motors generally produce peak torque within 5% or so from ~4000rpm to 5500rpm or so. They can extend that plateau further depending on the intake manifold setup. A Squaretop will stretch that to 6000rpm, and a short-runner Honda manifold a bit further than that. Look at the two charts I posted a couple of posts ago - Acamas has a big torque spike at 4100 owing to a bit of boost overshoot, then tapers to a very flat torque plateau at ~400wtq from 4400-5500rpm. Boost is flat through this area. Theseus' old 2871R plots had very stable boost control all through torque peak, and more than 280wtq from 4200-6400 on a 294wtq peak.

 

Yeah, but RTC's virtual dyno plots are FLAT. It shows 290 wtq plus or minus about 2, from 3900 to 5500. 5% would be a 15 wtq swing, which just isn't there.

--Ian

 

I have logs and the tune on my thread. I'm still tuning vvt, but the torque flatness may be due to some boost being fed in there. VVT is oscillating like mad right now.

I understand that VD is sensitive to variations in the ground which is why I usually do a pull in both directions and look at both together on a graph. Truth lies somewhere in the middle. That said, I do need to get over to a dyno to see what this thing is actually putting down. I'm pretty happy with things regardless, but just curious is all.

 

No argument that RTC's VD numbers are flawed at best. Just saying that VVT motors produce a different torque curve than a 94-00 motor does

 

Dyno operator would be me (that is the raw dyno file I plotted in DynoJet viewer) guess I never looked closely at the scaling.

Wiring the wastegate shut on my currently stock bottom end would probably be a bad idea

Either way, that dyno day was not supposed to be representation of what my setup could do, it was a tuning tool. I used it to gather data at multiple boost levels so I could set up flat torque curves later on. My motor killing itself stopped that though.

I will say, 6758 at 7psi is still pretty fun

 

Bad for you, entertaining for us

 

Trade you a built shortblock for the carnage video

 

Numbers are just numbers. It's a tuning tool at the end of the day. All my runs have been done in both directions on the exactly same stretch of road. I'm controlling for the easy stuff but it's obviously far from perfect.

I want to hit the dyno with a new map sensor and a tune for 30psi. ******* stoked!

 

E85?

 

No, just lots of this

 

93 pump.

Thoughts and prayers.

Hopes and dreams.

And probably some of that octane booster **** for the lulz.

 

I had to start pulling crazy amounts of timing up there to make power without knock. Single digits timing is stupid.

Would not do again.

 

Yeah... But you're still pushing 30psi, do you know how cool the BOV will sound with that much boost?

Really cool

 

Welcome to 1700F+ EGTs. Good for melting stuff.

--Ian

 

MIATA FONDUE!

 

How far can you go with the boost levels before the EGTs reach stock valve melty levels? (1650F?)

 

It depends heavily on how much timing you run, and thus on how much octane you have.

--Ian

 

Anything less than 10deg of timing makes me nervous. In a track car, anything less than 12-13deg. If you need that much power in your track car, you need 100+ octane or E85.

 

I don't think my map goes down that low anywhere

 

Interesting. May I ask why? You´ve seen damage with that timing, or just afraid of EGT going off the charts?
Apples to oranges but I ran a stock turbo Evo 8 for years at the track on single digit timing at peak torque, 25psi, 93 oct. It didn´t burst into flames, regretably.
My only turbocharged miata experience involved this cutting edge ECU and a rising rate FMU. Miraculously it didn´t explode either.