12 psi dyno run for 140hp?
#1
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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
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
#3
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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.
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.
Last edited by kotomile; 04-28-2009 at 12:39 AM.
#4
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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.
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.
#7
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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.
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.
#8
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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
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
#9
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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
#10
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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.
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.
+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.
#13
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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 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
#18
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140whp at 12psi? Isn't that a little low?