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hustler 08-09-2008 12:53 PM

pre-dyno tuning / minimizing dyno time and ching-dow
 
I want to have my car in its best shape possible, to minimize the financial rape.

I can get all my start shit just fine, get my fuel table fine, and get enrichments done on the street, just like anyone else...I'm basically only going to the dyno for the spark table.

Is it a reasonable idea to advance my spark table on the street to the point of knock, then back it off 2* or so? This would give me all the time in the world to get the table advanced as far as it will go, in every cell. Then, when I get to the dyno, there is only one direction to go with the values, which will make everything go faster and cheaper. If I know the upper limit, there's only one way to go.

notable cross posting which inspired this thread:

Originally Posted by hustler (Post 294171)
well, the problem with that is how long it takes. Some want 6 hours to tune...I don't have that kind of money. I could probably get it done in 2 hours with supervision. Then, if I want to do a pull with new plugs...bam, another $120 in labor just to switch them out. When turbo to manifold studs start backing out...there's another $120 each time they tighten them. If they want to just drop my car off at this shop for tuning, they have no reason to do it as quickly as possible...they could probably do the work in an hour or 2, and they'd still charge me $1000.
Aside from exatorq in Dallas, everyone else quotes me the same garbage prices if I tell them "i only need spark tuned" versus "I don't know what I'm doing and I need you to do everything." It doesn't take 6-hours to make a spark table, if it does you need to reevaluate you skillset. Only one place has given me a realistic price-range.

I don't think begi would rip me off...but they're farming it out. At this point, I'm tempted to load up the miata and drive to hotlanta.


Most importantly, I want to learn how to do it, not just cut a check.


Originally Posted by hustler (Post 294190)
I have no problem getting everything set up, aside from spark. I've done it on my car, a friend's car, and a turbo car.

Let me give you a quick run-down of how it works when you try to get a ballpark price.

call #1:
"how much to just tune the spark table, and make minor adjustments?'
"well, blah blah blah you're shit is not adjusted right, we'll fix cold start."
"no, how much to just tune the spark table, and make minor adjustments?'
"$1000 or 6-8 hours, and extra to do stuff like change plugs"

Call#2, to the same place, a couple months later:
"i'm dumb and need you to set up everything on my car"
"$1000 or 6-8 hours, and extra to change the plugs"

I've found one guy who said he didn't know MS, but wanted to work with it. He said he'd work the dyno, and tell me where to add or pull values. I think I just answered my own question.

p.s. Its kind of cool to search through this thread and see how far my knowledge has expanded from knowing nothing about MS to my moderate level today. Thanks for the help over the years.

hustler 08-09-2008 12:55 PM


Originally Posted by y8s (Post 294318)
if you're going to tune your spark on a dyno, there's no point in having a "road tune" first. you can tune a fuel curve on a loading dyno in about 5 minutes.

I find that it's real hard to do a "stay in a load site" method of tuning spark. better to do various rpm runs at different loads. basically paint lines across the map. you'll start to see trends in power output as you change spark (and fuel).

so maybe what you want to do is use the same off-boost spark as everyone else and then set your boost to various levels and run through the RPMs that way and tune each boost level individually.

but i have an 8.8:1, 1.9l (almost) motor, so I'm going to use radically different values.

y8s 08-09-2008 01:14 PM

yeah and you're also not going to get max power below 0psi so it doesn't really matter if you're +/- 3 degrees from peak power output at 80kpa and 4000 rpm.

you can do it on a dyno but i'd bet they can't hold the load that low anyway.

Stephanie Turner 08-09-2008 01:51 PM

The reason we have to pay for the Dyno Dynamics is because Corey actually operates it while Tim does the tuning. The dyno rates are very reasonable and Corey is not out to screw you. He is a good guy. If you want it done on the dynojet, it is much cheaper and we operate that dyno. If you need to change plugs or anything - go for it - you are more than capable and it is one less thing for us to do.

Tim can also do road tuning prior to the dyno. He usually spends two hours or so doing that before heading to the dyno. Call him if you have questions!
Stephanie

Markp 08-09-2008 01:51 PM

You don't need a dyno to tune the spark map of a car, but you do need a repeatable piece of road and someone in the car doing the tuning other than the driver. It is possible albeit more labor intensive to get a great map on the road, provided you have the right road and a car that is reasonably safe to drive.

You want to find a long uphill stretch of straight road in the middle of nowhere. Baker Grade in California is perfect for this but roads like this exist everywhere. Unfortunately you can't do the speed limited type of tuning that is possible on a dyno, but you can get really close, close enough not to matter.

Datalogs are your friend, stolen spark tables are your friend, remember your motor is likely to act in a VERY similar manner to most everyone else. Dyno time is really useful when you are looking for that last 5-10 HP, that's it. Everything else can be done on the road.

I would rent the dyno without any tuning support. Most dyno guys can't help themselves anyway, they'll likely jump in and help. Rent an hour, see how you do after you have really thoroughly road tuned it.

Mark

johndoe 08-09-2008 02:32 PM

I decided to quote you in this thread instead of continuing to jack the other:

Originally Posted by hustler (Post 294311)
try upping the req fuel to get more resolution out of the table. Suddenly this thread belongs in another forum.

I got a guys 1.6 to idle at 14.7 with 460's last weekend.

explain to me how changing the req fuel does anything to resolution? Currently my idle AFRs with 550cc injectors is 11-11.5AFR with Hi-Res. The VE numbers for the idle cells are 44 at a KPA of 28 so I think I have plenty of room to go up or down in my VE numbers.

If the idle is fast, say 1300RPM I can get the idle to 14.0 but obviously that's not the right way to go about it. I'm using DIY's setting for idle control. Is this an anomaly or is everyone idling 550s rich?

hustler 08-09-2008 02:40 PM


Originally Posted by johndoe (Post 294348)
I decided to quote you in this thread instead of continuing to jack the other:


explain to me how changing the req fuel does anything to resolution? Currently my idle AFRs with 550cc injectors is 11-11.5AFR with Hi-Res. The VE numbers for the idle cells are 44 at a KPA of 28 so I think I have plenty of room to go up or down in my VE numbers.

If the idle is fast, say 1300RPM I can get the idle to 14.0 but obviously that's not the right way to go about it. I'm using DIY's setting for idle control. Is this an anomaly or is everyone idling 550s rich?

think about the usable value range. I've heard this helps and might work if you don't want to switch to highres code.

johndoe 08-09-2008 02:44 PM

Let me quote myself:

Originally Posted by johndoe (Post 294348)
Currently my idle AFRs with 550cc injectors is 11-11.5AFR with Hi-Res.


hustler 08-09-2008 02:48 PM


Originally Posted by Stephanie Turner (Post 294340)
The dyno rates are very reasonable and Corey is not out to screw you. He is a good guy. If you want it done on the dynojet, it is much cheaper and we operate that dyno. If you need to change plugs or anything - go for it - you are more than capable and it is one less thing for us to do.

this is good.


Does anyone have a log or screenshot of an AFR target table that's been tuned by Tim? I want to make sure I don't end up with someone who throws fuel at detonation, rather than retarding spark...I know lots of people with 11.0-11.5 target AFR's and I don't think that's the best way to go about it. From what I've read 12.0-12.5 is the happy place for fuel, and pulling spark is the right way to go.

I'd also like to make a couple pulls at the end with a heatsoaked intercooler and a frozen intercooler to make sure the IAT math works in all extreme summer and winter temps.

hustler 08-09-2008 02:53 PM


Originally Posted by johndoe (Post 294351)
Let me quote myself:

i think values in the 40's are too big. With the 460's and stockers I've had the idle cell values around 19-26 in the VE table.

hustler 08-09-2008 02:57 PM

stephanie,
you guys have been great to me every step of the way, even when I'm a royal pain in the ass. I couldn't find Tim's email on your site, but I was going to link him to this thread and ask him to chime in.

Is there any chance you guys have a datalog or AFR target table you could post up from what Tim thinks a reasonable tune should look like, not for max power?

Sorry to be a whiny bitch.

johndoe 08-09-2008 03:08 PM

1 Attachment(s)
problem is if I go lower in those cells idle gets rough. Here's the current VE table that I'm tuning.

cueball1 08-09-2008 03:10 PM

I'm in there with John Doe. Right now my car is idling a little fast, 1200 rpms but it is solid in the mid to high 13 AFR's. My VE's around idle are 51's and 52's! That's with 550 cc Rx7's and using the DIY idle settings for the 1st page.

Don't know how you can be idling with VE's in the teens and low 20's!

Mach929 08-09-2008 03:52 PM

with my 620cc injectors i'm idling required fuel at 4.9 and 42 in cells, it's around 13.8, but i'm working on trimming it once i get the coolant related air density sorted because it was heatsoaking too lean to idle right, probably end up 38-40

johndoe 08-09-2008 03:55 PM

What the shit? You have bigger injectors running leaner? Mind sharing your idle settings?

hustler 08-09-2008 04:02 PM

change the req fuel, drop the values, if it doesn't idle, switch to highres. If its getting rough the jack with the spark advance and smooth it out.

how am I possibly answering questions on MS?

johndoe 08-09-2008 04:11 PM

Obviously the quoting myself thing didn't stick: I'M RUNNING HI-RES ALREADY!

hustler 08-09-2008 04:23 PM


Originally Posted by johndoe (Post 294380)
Obviously the quoting myself thing didn't stick: I'M RUNNING HI-RES ALREADY!

sorry, I'm gay.

johndoe 08-09-2008 04:30 PM

That's okay, I wouldn't get mad at you for something that can't be helped.:love:
Anywho you've gotten a car to idle well with MS while I still fail.
Back to the topic at hand we need help!
http://i19.photobucket.com/albums/b1...7910541341.jpg

hustler 08-09-2008 04:43 PM

1 Attachment(s)
fuck with spark and make it idle at 14.7, like a man.
Attachment 211882


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