Guess my Dyno
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
guys look at his first graph it is jaggy too plus the graph does not show horsepower equals torque at 5250 rpm there is something wrong with that dyno. torque always equal horsepower at 5250 that is a constant the jaggedness is ill bet it is slipping all over that dyno :cheers:
[whispers] Look at the two sides, it is using different scales for each. [/whispers] ;)
Thread Starter
Drifting
Joined: Jul 2001
Posts: 1,751
Likes: 1
From: Miami, FL, USA
Re: (BBA)
"If your iac counts are high...it means your min idle is set too low to start with...in effect, its the opposite of a vacuum leak, so checking for a leak is a waste of time."
Okay, so how do I set my min idle?
I always set the TPS voltage first, then adjust the throttle linkage to idle around 800 rpm, and re-check the TPS voltage.
Is this wrong?
Okay, so how do I set my min idle?
I always set the TPS voltage first, then adjust the throttle linkage to idle around 800 rpm, and re-check the TPS voltage.
Is this wrong?
Melting Slicks
Joined: Sep 2000
Posts: 3,099
Likes: 0
From: PITTSBURGH PA
Cruise-In IV Veteran
Cruise-In V Veteran
Re: (CORKVETTE1)
let me take another stab at this if it was running out of fuel from filter and or pump i do not think it would be pulling so hard after it went full lean on the graph the af came back in line if it was running out of pump or pluged filter that would not have happened :cheers:
Thread Starter
Drifting
Joined: Jul 2001
Posts: 1,751
Likes: 1
From: Miami, FL, USA
Re: (CORKVETTE1)
Yes, that makes sense....
Im going to check EVERYTHING today regardless. It cant hurt!
BTW the weather today.....
Very Sunny, not a cloud in the sky....about 65 degrees.....FREE AC IN THE GARAGE!!!!! WOOHOO!!!!
Im going to check EVERYTHING today regardless. It cant hurt!
BTW the weather today.....
Very Sunny, not a cloud in the sky....about 65 degrees.....FREE AC IN THE GARAGE!!!!! WOOHOO!!!!
Drifting
Joined: Apr 1999
Posts: 1,261
Likes: 6
From: Middletown New Jersey
Re: (GusBustamanteJr)
I personally wouldn't trust a wideband O2 that takes it's readings after the catalytic converter. I have had both done, tailpipe sniffer and the extra bung I had put in the header and their definitely was a difference. Unfortunately, I lost the dyno graphs so I can't post them.
That being said, the relative leaness in parts of the curve do have to be addressed as was mentioned earlier.
That being said, the relative leaness in parts of the curve do have to be addressed as was mentioned earlier.
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Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
One thing at a time. :) I think we can assume the fuel pump is good due to the fact that the A/F came back into good territory at such a high RPM. If the pump couldn't keep up there is NO way it would be able to feed the engine at 6000 like that.
So... whats left.
1. Vacuum leak? (none detected so far)
2. Tuning? (my bet, nothing is right the 1st time)
3. ?????
The engine was lean no doubt and it also was getting knock retard of upwards of almost 8 degrees from what I saw. The problem is if that knock is being created from the lean condition or just from too much timing. I'm going to bet a lot of it will disappear once the A/F is brought into a more acceptable level across the board.
At the very least I would start with adding a bunch of fuel from the 4000-5500 range. Regaurdless if there is a vaccuum leak or an exhaust leak there should be a somewhat constant trend in the A/F readings. That baby has a huge camel hump in it. You'll see that nasty drop in power at 4900 go away and things should start to smooth out.
Once things get squared away with the fuel you should be able to play with the timing some more and more finely tune the fuel at that point.
So... whats left.
1. Vacuum leak? (none detected so far)
2. Tuning? (my bet, nothing is right the 1st time)
3. ?????
The engine was lean no doubt and it also was getting knock retard of upwards of almost 8 degrees from what I saw. The problem is if that knock is being created from the lean condition or just from too much timing. I'm going to bet a lot of it will disappear once the A/F is brought into a more acceptable level across the board.
At the very least I would start with adding a bunch of fuel from the 4000-5500 range. Regaurdless if there is a vaccuum leak or an exhaust leak there should be a somewhat constant trend in the A/F readings. That baby has a huge camel hump in it. You'll see that nasty drop in power at 4900 go away and things should start to smooth out.
Once things get squared away with the fuel you should be able to play with the timing some more and more finely tune the fuel at that point.
Thread Starter
Drifting
Joined: Jul 2001
Posts: 1,751
Likes: 1
From: Miami, FL, USA
Re: (scorp508)
Base timing was just set after rebuild- right at 6. A new knock sensor wouldnt hurt, huh??
Im working on those items right after I test the Camber Brace I just installed...that thing looks sweet in there!!!!
About the heated O2, I could wire it up the the ECM lead right?
Also, a few threads up, I asked the process for adj the idle....was that correct?
Thanks
Im working on those items right after I test the Camber Brace I just installed...that thing looks sweet in there!!!!
About the heated O2, I could wire it up the the ECM lead right?
Also, a few threads up, I asked the process for adj the idle....was that correct?
Thanks
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Well your knock sensor is working since the ECM is reducing timing, but I mean working with the timing internal to the chip.
A heated O2 is always good. You could wire it up to the fuel pump relay so that it is only switched on when the fuel pump is running.
As for the idle, I don't know that one. :)
A heated O2 is always good. You could wire it up to the fuel pump relay so that it is only switched on when the fuel pump is running.
As for the idle, I don't know that one. :)
Thread Starter
Drifting
Joined: Jul 2001
Posts: 1,751
Likes: 1
From: Miami, FL, USA
Re: (scorp508)
Well today I fixed the idle problem. Seems the TPS had lost its setting, and we didnt set the min idle setting with the IAC unplugged. I followed the tech tip, and its idling great now.
I might do the heated O2 tomorrow.
Tonight we are going out to eat and relax with the babies!
What the wife doesnt know is that they are having a cruise and show at the place we are going to eat!!!!!
I might do the heated O2 tomorrow.
Tonight we are going out to eat and relax with the babies!
What the wife doesnt know is that they are having a cruise and show at the place we are going to eat!!!!!