Poor Dyno numbers... need suggestions
04-13-2012, 12:11 PM
#31
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op,
seriously, your power numbers are very good....
i can only imagine what having 100 hp more at the wheels (than what i have) would be like.
you've got a hell of a ride. just drive it and enjoy.....
he's not there yet....
but running too much boost will eventually lead to this eventuality....
seriously, your power numbers are very good....
i can only imagine what having 100 hp more at the wheels (than what i have) would be like.
you've got a hell of a ride. just drive it and enjoy.....
he's not there yet....
but running too much boost will eventually lead to this eventuality....
04-13-2012, 12:55 PM
#32
Pro
Thread Starter
LoL yeah that's what my roommate said, that I can still drive the car. His modded to hell mustang had an ecu problem that was keeping him from even starting the car for the last month.
04-13-2012, 01:08 PM
#33
[quote=400hp944;9442456]
+1
I will get that checked out, but that is lower on my list of things to verify.
It won't take long at all to verify. Set the flywheel to TDC and look through the inspection hole on the cam cover. If you are off by only 1 tooth, it can make a big difference. Unless you have a major leak or as Tony suggests, the waste gate, I would check this first. It's simple and easy and you can rule it out if it's ok.
I just went through this. My HP and TQ curves were shifted way to the right. Spool up sucked and power was down while still holding 17 PSI to red line. It may not be your problem, but it's an easy check.
It won't take long at all to verify. Set the flywheel to TDC and look through the inspection hole on the cam cover. If you are off by only 1 tooth, it can make a big difference. Unless you have a major leak or as Tony suggests, the waste gate, I would check this first. It's simple and easy and you can rule it out if it's ok.
I just went through this. My HP and TQ curves were shifted way to the right. Spool up sucked and power was down while still holding 17 PSI to red line. It may not be your problem, but it's an easy check.
04-13-2012, 03:01 PM
#34
Burning Brakes
Tony - can you elaborate on what sort of wastegate issues this causes? My interpretation is that the wastegate is somehow leaking boost and thus limiting spool rate - is this accurate? How does a MBC play into this? Finally, if you have a small exhaust leak, how much does that impact results?
I have a very similar setup and think I'm having similar issues. I am currently chasing what appears to be a crack in the header or the x-over pipe.
I have a very similar setup and think I'm having similar issues. I am currently chasing what appears to be a crack in the header or the x-over pipe.
1) There is no "base line spring". You specify what the spring should be (at least that's how I order the wastegates)..
2) Just because you have it in "dual port" doesn't mean it's plumbed properly.
3) Manual boost controllers generally suck. And a lot of that has to do with the wastegate plumbing and spring rate. A properly setup wategate can do a decent job with a manual bleed type boost controller... (the operative word here is "properly setup".
That said... where is your boost plot on the dyno chart? That will tell the story with respect to proper wastegate operation. If you don't have that... then you need to get it. Without it... you're shooting in the dark....
In short..... it's clear that some part of your config is not properly setup.... which is reflected by the laggy TQ curve.
TonyG
2) Just because you have it in "dual port" doesn't mean it's plumbed properly.
3) Manual boost controllers generally suck. And a lot of that has to do with the wastegate plumbing and spring rate. A properly setup wategate can do a decent job with a manual bleed type boost controller... (the operative word here is "properly setup".
That said... where is your boost plot on the dyno chart? That will tell the story with respect to proper wastegate operation. If you don't have that... then you need to get it. Without it... you're shooting in the dark....
In short..... it's clear that some part of your config is not properly setup.... which is reflected by the laggy TQ curve.
TonyG
04-17-2012, 08:57 AM
#36
Pro
Thread Starter
The WG is installed correctly, crossover going into the bottom, and the dump is in the side.
*update*
I rewired the knock sensor and had a hell of a time with a possible exhaust leak from the crossover to wastegate, but I believe that is resolved, and no other areas seemed to be leaking with the soapy water test. No big noticeable changes with spoolup but the car is running a bit better off boost. I don't have time right now to really keep checking things myself, as I'm moving at the end of the month. I've got a tentative appointment with my buddy's shop to double check everything if I get enough progress done with the move. If not It'll be the middle of may before I can really get things sorted.
04-17-2012, 10:46 AM
#37
Rennlist Member
27-6 and 26-8 are very close to being the same turbo. When I had my 26-8 and Greg East had his 27-6 our cars were basically the same, with all our other mods being similar.
04-17-2012, 11:14 AM
#38
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When I was running a K27-6 (with Authoirty MAF) I made about 255hp (uncorrected) at 5300ft on a Dynodymanics dyno. The corrected numbers I thought were BS so I don't claim them.
This number seemed to be "about right" as at 5800ft I ran 103mph quarter mile speeds. Figuring me and the car are about 3200lbs (i don't remember exact weight when I weighed me and the car) that would indicated a HP of about 287hp (drag race calculators normally are flywheel hp).
Keep in mindwhat type of a dyno you run on matters for power also.
At 300hp from a K27/6, I think you are getting good power out of it and are about where you should be.
-Dana
This number seemed to be "about right" as at 5800ft I ran 103mph quarter mile speeds. Figuring me and the car are about 3200lbs (i don't remember exact weight when I weighed me and the car) that would indicated a HP of about 287hp (drag race calculators normally are flywheel hp).
Keep in mindwhat type of a dyno you run on matters for power also.
At 300hp from a K27/6, I think you are getting good power out of it and are about where you should be.
-Dana
04-17-2012, 07:40 PM
#39
Rennlist Junkie Forever
The problem is not the power. It's the TQ curve.
The ~6 turbine should be spooling much sooner and harder.
The TQ peak should be <3500 rpms with that turbine... and is the very reason these turbos are so great on 2.5L street cars.
TonyG
The ~6 turbine should be spooling much sooner and harder.
The TQ peak should be <3500 rpms with that turbine... and is the very reason these turbos are so great on 2.5L street cars.
TonyG
05-06-2012, 12:47 PM
#42
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I should have put a NOT in the sentence. The knock sensor does NOT have a polarity.
That is strange, went back to the post that needed the "NOT" inserted and I am locked out from changing it. Appears there is a time limit to change posts. That isn't a smart thing to.
That is strange, went back to the post that needed the "NOT" inserted and I am locked out from changing it. Appears there is a time limit to change posts. That isn't a smart thing to.
05-06-2012, 12:52 PM
#43
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05-06-2012, 12:55 PM
#44
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1+ to both
I just had a leaky DV, it caused a lazy or stepped boost and sometime would make a fluttering noise when it first would go into boost. It also caused me to spin at the track when it changed my boost just as I was powering out...big snap spin.
I just had a leaky DV, it caused a lazy or stepped boost and sometime would make a fluttering noise when it first would go into boost. It also caused me to spin at the track when it changed my boost just as I was powering out...big snap spin.
05-06-2012, 02:17 PM
#45
Pro
Thread Starter
***
So I took the car out to Lowes like an hour ago to pick up a 3/32" allen wrench to adjust the fqs settings,since all of that stuff is packed up in my new garage. The Car pulled much better on the -4% #2 setting. but the afr was 11.8-12.0 at 4-5k rpm.
Here's the thing... on the way back from lowes (maybe 3-4 miles away) the car would idle really low at stoplights so I'd give it gas to keep it around 1k. About a mile from my apartment complex the car flat out died. The tach did bounce and try to start but no go, and each time I'd get a LOUD backfire. I tried several fqs settings and still nothing but a big backfire each time. I ended up smacking the ecu and the car started, I got another half mile down the road then it died again. I hit the ecu a couple times and the car cranked right up so I got it back home.
So, I need to go over the dme now. This hasn't ever happened before with the car but I know that the dme's can do that.
Can someone refresh me on what a faulty dme does, as in would it be linked to my slow spool?