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alfadriver
alfadriver Reader
10/21/08 2:08 p.m.

Reasonable.

But you'll find that spool rate is a strong function of the turbo AND the transient calibration.

It's at least worth the try.

E-

DILYSI Dave
DILYSI Dave SuperDork
11/24/08 6:14 p.m.

Fast forward a month...

So, I have now spent some time on the dyno with E85. Not my car, but another buddy's.

It was educational. The timing curves hardly changed at all from the gas setup. Fuel curves did understandably get richer. Any advise on AFR's to aim at? From experimenting we kind of decided on .85 Lamda as the best power, but we didn't want to get too radical in either direction and start breaking stuff.

wherethefmi2000
wherethefmi2000 Reader
11/25/08 12:10 a.m.

well as close to 1 as you can get without det is what you want. I't all going to depend on the conditions that you encounter.... I know not much help. know that advaning timing on my wrx netted some really decent gains, also you need to look into injector latency and flow rates. I know that the stock 550cc injectos wouldn't cut it tuning for e85, had to neuter them to flow about twice that.

DILYSI Dave
DILYSI Dave SuperDork
11/25/08 9:37 a.m.

We never experienced detonation, going from .7 to .9. It's a pretty detonation resistant motor. Given that it seems that "safe" is easily achievable now power is the bigger goal.

On timing, we already had a timing curve that had been optimized for 93 Octane gas, but we really didn't see any advantage to changing it much. Added a bit more advance in the lower RPM's, but anything we did up top lost power.

wherethefmi2000
wherethefmi2000 Reader
11/25/08 9:49 a.m.

Tuning is fun huh, That was the same way with my wrx make gains in some places, don't see so much anywhere else, but we weren't trying to run on the edge or anything. interesting thing for me was when we ran 19psi of boost it lost power from 18.5psi funny how just a little bit can make a big difference

Paul_VR6
Paul_VR6 New Reader
11/25/08 10:55 a.m.

Did you try changing the timing around a bit while running the richer AFRs?

DILYSI Dave
DILYSI Dave SuperDork
11/25/08 1:20 p.m.
Paul_VR6 wrote: Did you try changing the timing around a bit while running the richer AFRs?

Nope. That's some of the guidance I'm looking for though - what kind of targets or trends should we be working towards?

wherethefmi2000
wherethefmi2000 Reader
11/25/08 1:40 p.m.

damn I had a tuned e85 map for my wrx but that's useless to you, I am going to slap my forehead and stop posting on this topic lol.

Paul_VR6
Paul_VR6 New Reader
11/25/08 3:01 p.m.

Usually I tune a car to a gas AFR of 11.5:1 and then play with timing to get to best hp, then I go a little richer and do the same. If it keeps picking up I keep going. The more wild the setup the richer things like to be.

Sorry about the gas afr but I can't think in lambda.. you're smart enough to convert should be around .7x

DILYSI Dave
DILYSI Dave SuperDork
11/25/08 3:51 p.m.

Gas AFR of 11.5 = Lambda of .78

You tune a gas motor for this or an E85 motor?

DILYSI Dave
DILYSI Dave SuperDork
1/21/09 11:10 p.m.

Update - My car is running on E85. It sees the dyno on Saturday.

wherethefmi2000
wherethefmi2000 Reader
1/21/09 11:42 p.m.

Nice How's is it running?

DILYSI Dave
DILYSI Dave SuperDork
1/21/09 11:55 p.m.
wherethefmi2000 wrote: Nice How's is it running?

It's OK. I drove it a couple of weeks ago on race gas. It's quick. On the E85, I adjusted the tune enough to get it to idle and have decent throttle response while not making the wideband do anything ugly, and that's it until it sees the dyno. If the dyno session on Saturday goes well, it may see it's first event in years on Sunday,

alfadriver
alfadriver Reader
1/22/09 6:51 a.m.

I missed the second coming of this thread, so I'm glad the third came when I was around.

One note about the a/f and spark- IF your engine isn't knock sensitive, chaning the a/f isn't going to do much- the big gain going from stoich to .85 is typically more agressive spark. The actual power gain from the fuel ranges from 2% to 5%, but the spark gains can be a lot more than that.

If you are not knock sensitive at all (and be careful of hot weather), then .85-.9 lambda is perfectly fine.

One other "gain" of the richer a/f is cooler exhaust- that's the other legal reason to go rich is to keep the engine and exhaust components from getting damages (and when I say legal, that's for us, not you.... if you know what I mean).

Spending a few hours on a chassis dyno is a great way to get the base map nice and solid, but just know, taking data EVERY TIME YOU DRIVE THE CAR will be good to make sure the calibration is nice and robust. I'd estimate for every hour of dyno time we do, there's at least 10x of vehicle data we take and tune to. Basically, when you drive, rarely is it a 4th gear WOT accel, and that's all you are really testing. So take data- tune cold start/warm up, and transient fuel (and spark, if needed). That's what will take your fast car, and turn it into a real barn burner- no hesitations or whatnot.

Eric

Paul_VR6
Paul_VR6 New Reader
1/22/09 8:40 a.m.

Dave, I was tuning an E85 fueled engine for a gas afr or 11.5:1, you got the equiv lambda right. I agree with the fuel gains in the 2-5% with timing being on top of that. Find the max power AFR first at or near normal race gas ignition values and then tune ignition from there.

DILYSI Dave
DILYSI Dave SuperDork
1/22/09 12:29 p.m.
alfadriver wrote: One note about the a/f and spark- IF your engine isn't knock sensitive, chaning the a/f isn't going to do much- the big gain going from stoich to .85 is typically more agressive spark. The actual power gain from the fuel ranges from 2% to 5%, but the spark gains can be a lot more than that.

It is fairly knock resistant. That said, the ECU makes no adjustments for knock (no knock sensor) so I'm going to have to be conservative.

As for logging it in normal driving, The couple of hours it spends on the dyno will probably be more than the amount of run time it will see for the rest of the year. That's the fate of a dedicated autox car.

alfadriver
alfadriver Reader
1/22/09 1:11 p.m.
DILYSI Dave wrote: It is fairly knock resistant. That said, the ECU makes no adjustments for knock (no knock sensor) so I'm going to have to be conservative. As for logging it in normal driving, The couple of hours it spends on the dyno will probably be more than the amount of run time it will see for the rest of the year. That's the fate of a dedicated autox car.

Well, then make a bracket to house the laptop for at least a handful of events. That's a great place to take data.

E-

DILYSI Dave
DILYSI Dave SuperDork
1/24/09 4:12 p.m.

175HP / 172 Ft-lbs. Spools instantly. Positive manifold pressure at 1700 RPM. 8psi @ 2800 RPM going to 10 psi at 7000 via a small bleed. Torque peak is at 2900 RPM. It's like no Honda graph you've ever seen. Took it on a damp street with street tires and first gear is useless, followed by 2nd gear requiring constant modulation in order to not be. In first, it literally spins the tires so fast it sounds like you're revving in neutral.

Looking at the data now, off the clock, it looks like I should have leaned it out a bit more up top. No sweat though - rich = safe.

Hal
Hal HalfDork
1/25/09 6:59 p.m.

Looks real good, I assume this is with the E85. Definitely not like any Honda dyno graph I've seen. Now you need some big sticky tires and a few spare axles.

MadScientistMatt
MadScientistMatt HalfDork
1/25/09 8:05 p.m.

Nice broad torque curve. Is that a D16 by any chance? Almost looks like you've taken a D-series torque curve and near doubled it at every point.

DILYSI Dave
DILYSI Dave SuperDork
1/25/09 9:00 p.m.

Yes - D16A6 with 89 Integra pistons (11.1:1 CR) and a T25 on custom plumbing. The big sticky tires are going to be 275/35/15 Hoosiers on 15 x 9 rims. Hopefully the axles will behave. There are quite a few drag cars with more power that are running stock axles, although they are putting their power down in a straight line while I'll be doing so turning.

It's definitely a data point for the "turbo = HP, supercharger = torque" crowd. It's all about sizing.

And Matt - after spending a couple of hours on the dyno with the Zdyne, I want a Megasquirt more than ever. The Zdyne isn't bad, but it's limited by being based of of the OE ECU. For instance, it has great resolution below 1500 RPM, but after that the resolution gets worse as you move up in RPM. Good for Honda, bad for racing. Throw in some desired features that aren't supported on the Zdyne and I see myself moving over at some point.

MadScientistMatt
MadScientistMatt HalfDork
1/26/09 11:37 a.m.

Very cool, I've been sometimes thinking that my own Civic could use a bit more low end torque.

Now... what sort of features does the Zdyne not support? I'll see what I can come up with.

DILYSI Dave
DILYSI Dave SuperDork
1/26/09 2:30 p.m.
MadScientistMatt wrote: Very cool, I've been sometimes thinking that my own Civic could use a bit more low end torque. Now... what sort of features does the Zdyne not support? I'll see what I can come up with.

Data logging is a big one. The ability for the ECU to self tune seems pretty awesome. Also - antilag may prove useful as well.

93celicaGT2
93celicaGT2 Reader
1/26/09 3:14 p.m.

Any particular reason you aren't using Crome or anything like that?

You can datalog using the stock chipped ECU.... moates.net sells the necessary stuff. Ostrich is what i believe it was called.

You can set up antilag or at least a flat shift with Crome as well.

DILYSI Dave
DILYSI Dave SuperDork
1/26/09 3:29 p.m.
93celicaGT2 wrote: Any particular reason you aren't using Crome or anything like that?

Because when I started this build 4-5 years ago, a Zdyne Gold was as good as it got. That's what I get for buying technology on the front end...

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