12 psi dyno run for 140hp?
 

First off my set up is a 1.6L with a megasquirt, 550cc injectors, a welbro 255 fuel pump, 2.5 in exhaust without cats, front mount intercooler, and I plan on adding a wideband before I do any more tuning.

I took my car to the dyno over the weekend to get a baseline tune, and it looks like I am only putting getting about 140whp.

It was a dynojet I ran on, not sure if hat makes much of a difference, and I was only running it a little over 6000rpm, due to misfires above that range.

First obvious problem, the misfires, I posted on a discussion on spark plugs on this already, but any advice would be helpful. As of now my plan is for new plugs with narrower gaps. I saw a posting on a better spark circuit, I am guessing that would help, but not sure what the root cause of the issue is.

On the wideband at the dyno I was putting about 12:1 AFR, with my boost peaking at 12.62 and tapering off (I found a vacuum leak after that I need to fix, cracked hose causing a high idle).

The torque curve is anything but smooth, and dies off drastically above 5000rpm. I am wondering if I am not running enough timing, too much fuel or something totally different. Attached are my tables, and current tune.

I realize that this is a long post, that is rather redundant to the other noobs asking how can I get 250hp with 15 min or work, so my apologies in advance if I am missing a thread that can help figure out if my tables are screwed up or if there is something else I should pursue.

thanks for the help,
Tripp

You forgot to mention the turbo you are running...

About the spark, you absolutely need more spark energy or less gap to jump. Both are doable, getting more spark (COPs!) is the more expensive solution but worth it. Something sounds amiss with your ignition, what was the gap when you dynoed?

Edit - just found your other thread. COPs might not be in the budget, seeing as it's a $2009 car.

Splitime - it's a Greddy.

You ought to be a little over 200ish at 12 psi, something's up.

Look at your engine constants under the basic settings tab.

Req Fuel looks about right, but what prompted you to set the injector opening time and battery voltage correction like that.

They should be 1.00 and 0.10 respectively.


EDIT: Also, don't take offense, but did you actually set the timing (trigger angle) in MS. Yours shows 65, which is a default, or atleast what everyone starts with. I would doubt that you would end up with exactly that trigger angle.

Also, your overboost protection is set at 5.9...so I don't know how you were hitting 12 psi.

Yeesh, if it was just overboost... oh man.

Eh, was just pointing out what I saw. He already said he's seeing higher boost on datalogs...

There are some problems with that setup though. The tables aren't way off or anything. VE looks a little rich, and spark is a little aggressive for my tastes, but he says he's in the 12s, and I guess they were listening for knock.

I would check into those values on the Engine Constants. I can't remember the exact reason, but remember reading that it is pretty important they be set that way.

140whp from 12 psi? Sign me up too.
Seriously though, something is way off. Check your compression and make sure you aren't blowing boost into a toasted motor.. And get your MS settings right as gospeed has pointed out.
-Ryan

That's how I was feeling.

I have my boost controller adjsuted to allow the 12-14 psi, but I guess I need to adjust MS also. I am still new to MS and I know I need to get more familiar with the Megatune manual.

Thanks for the ideas to start with. I have been thinking that I need to do a leakdown and compression test to see what is going on.

thanks
Tripp

+1, it takes an injector 1.0ms to open and close, not 10.0ms


and with overboost set to 5.9psi, there's no way you hit 12psi on the dyno.


post the logs on the dyno...and the dyno plot.

I wasn't disagreeing. It would just really suck for him if all of this head-scratching was over the overboost protection setting.

OH yeah, been there recently, that is one fubarred feeling, like you were fighting kudzu.

I think his other settings need some straightening out, then he can get back to regular tuning like spark gapping and datalogging.

THEN back to the dyno.

I have the dyno sheet and the datalogs from the dyno at home, I will post them tonight.

I have a mechanical boost guage that is reading up to around 14 psi at max boost on the street currently (no changes so settings since the dyno run).

Thanks for the pointers as to where I need to start straightening out my set up.

-Tripp

I think savingtons's overboost protection has never worked from the get go, maybe tripp has the same problem.

What exactly does the overboost protection do other than open the EBC completely? I think he's running an MBC, so his overboost might not be doing anything.

overboost protection activates a rev limiter. You can shoot past it if you stay WOT, but you're also retarding timing pretty heavily.

Only if his MS MAP signal line was run off the wastegate can side of the MBC.

The combustion temps would SOAR then, thats not a good thing and definitely an easy way to kill an engine. The overrichness probably kept the engine cool enough if it was actually pulling timing while overboosting but that is no way to run the engine.


140whp at 12psi? Isn't that a little low?

Only about 40% right? Nothing too bad...

If you did set the timing with the trigger angle did you make sure to click on "unlock" instead of just pressing "Ok?" It seems stupid but it happened to me and all of a sudden my car got much faster!

I made 173 HP on a Mustang dyno at 13PSI with the shitty greddy down pipe, and band aids.

ok...


Seriously, that's more than I'm making right now I'm sure. I'm only running 9psi though. For the cars I can run dead even with, I estimate I'm pushing 155-160 by comparing power/weight ratios(calculating 12% drivetrain losses for their crank hp).

173hp is actually a good deal more respectable than 140hp with more (EDIT, less) boost.

40% may be an overestimate, but he's missing atleast 50whp there, which is HALF of what he should anticipate as an improvement of N/A power.

There's a big difference between missing 15-20 ponies due to a shitty downpipe and bandaids...and missing half of what you built the setup for due to a crummy tune or whatnot.

The point I was making is 140HP on his setup is far from what his potential is.
With a free flowing exhaust and a good tune his car should make another 100HP. There have been several greddy / MS equipped Miata here making 240+HP.

Ok, then we were saying EXACTLY the same thing.

40% of 240whp is . . . . 96whp.

140+96=236~240

What he should be making.

I was being sarcastic, sorry for the misunderstanding.

You're right, he is way behind his potential, which I think we've all posted plenty about. Maybe we should get back to helping him figure out where he's fucking up.

+1

See sig :giggle:

No offense taken, I have not changed that setting, I am still very new to megasquirt, so I need to play with the settings. The car already had the MS in it when I bought it, and the only tweaks I have done were at the dyno (done by the guy at the shop). I am hesitant because I don't want to blow the motor by doing something dumb.

Thanks for the pointers.

That is DEFINITELY something that will blow up the motor!

Please pull out the timing gun, or go buy a cheap HF one at least.

Go through Brain's instructions which entail:

here are the logs from the dyno run, I exported them to excel.

Looks like I am running fatter then I had thought at first (dipping to mid/low 11's for AFR. Unfortunately I do not see boost logged in the dyno runs.

you didn't log it with your MS?


the AFRs look fine.



zip and attached the drf files while you are at it.

I didn't log it with MS, was trying to figure that out and then got tied up in the tables and dyno runs. Next time I tune I will need to set up MS to log first.

Attached are the dyno files (I am assuming drf format)

I adjusted the battery voltage correction to 0.1 v and the injector times to 1, I still need to burn these changes to the ECU. (please let me know if it looks correct in the table pictured, seeing that I am going from a factor of 10 to 1 I just want to make sure I am not going to go too lean or anything)

The overboost from what I could see (not hooked up to the ECU) was 195kpa, I bumped it to 215kpa (table pictured)

I will need to get a timing gun (learn to use it, which should not be an issue) and ensure that the timing is done correctly. I might wait for the weekend for that one.

thanks!

Now your overboost says -10.7???

Maybe some difference in values in our megasquirt folders is screwing me up. You will KNOW if it cuts in though, and easy to fix.

I would fix timing quickly.

Changing those injector values may require a datalog or two to fix.

looks like the tables did not upload that time

there's just no way that was 12psi....

http://www.boostedmiata.com/dynos/tripp_dyno.jpg

I need to fix a couple things first (hook up my wideband, fix the cracked hose I have, do something about my spark blowing out), but I will try to do a couple pulls on the street and data log in MS before I change my ECU settings to the ones I posted last night.

But I am seeing the boost guage get in the 12-14 range and the log from the dyno which was hooked to my intake manifold was reading a max boost of 12 psi. I will take a picture of the dyno sheet and post it tonight if that helps on the boost question.

i'm having trouble believing that's 12psi too, looks a lot like stock greddy kit

Holy FAIL

oh okay i see that data....using the stock downpipe, cat and exhaust?

but notice where the boost was when you hit peak RWHP...

http://www.boostedmiata.com/dynos/tripp_dyno1.jpg

no cat, stock downpipe, free flow exhaust only a resoniator, no muffler

The boost might be leaking through the hose I need to replace (it is not a main intake line but could be a factor). Also, the air filter is not the largest (it is a HKS hemisphere one), I am looking to move to a larger cone filter.

Any other thoughts?

Yes actually...

Please set your timing (or confirm it's correct) before doing ANYTHING.

timing is on the agenda for this weekend, borrowing a timing gun from someone at work.

thanks

three things i'd for:


a boost leak.
a potato stuck in my tailpipes.
incredibly retarded ignition timing.

I am hoping to do the timing this weekend, then the wideband O2.

thanks

when doing the o2 I will check for potatoes

if not the timing there appears to be something retarded with the way my car is running, hopefully the timing will help

Unfortunately, I have not gotten to try to correct the issued I have been having with the Miata until today (hoped to do it 2 weeks ago). I was checking the timing and it seems WAY off. My idle is high and not the most constant, which I am sure is not helping. I am posting a (blurry) picture showing where the timing mark I found (and then added whiteout so I could see it) is, compared to the stationary marker.

Any thoughts:

Heh. I'm guessing you're not actually idling at 50° BTDC. :D

Pull the #1 spark plug. Place the oil dipstick down the hole. Rotate the crankshaft by hand (well, by wrench anyway) while observing the up-down motion of the dipstick relative to the mark on the pulley. Ideally, the dipstick will reach apogee when the mark on the pulley is at 0 (or T) on the indicator.

If this is not the case, then the outer ring of your pulley has slipped relative to the hub.

Thanks Joe! I was looking at how far off that was and thought that something had to be wrong, no way it could run with timing that far off.

No, you can't. My overboost protection shuts the fuel injectors off at 17.5psi.