Dynoed car have problems.
Thread Starter
Registered User
Joined: Sep 2002
Posts: 214
From: Hayward, CA
Dynoed car have problems.
Here is the graph:
http://img119.exs.cx/img119/9108/sherwindyno2.jpg
I have the 230/236 112LSA cam with Lloyd Elliot heads fully ported. I have no clue why the horsepower goes from 292 to 314. I was planning on getting it dyno tuned but found some issues so I decided to fix them first. The opti is still original as is most of the other sensors. Torque also seems extremely low for this setup. The last run we hooked up autotap and saw that there was negative timing. The dyno operator said this was the first time he's seen values in the negative. I've done research and seen that this is normal. The car did need a tune as the fuel trims are off. I would think there would be more power than this without a tune as well as no jagged line on the graph. The dyno operator said there was definately something wrong since this setup should give more power. I've also changed the spark plug wires twice already and would hate to do them again.
http://img119.exs.cx/img119/9108/sherwindyno2.jpg
I have the 230/236 112LSA cam with Lloyd Elliot heads fully ported. I have no clue why the horsepower goes from 292 to 314. I was planning on getting it dyno tuned but found some issues so I decided to fix them first. The opti is still original as is most of the other sensors. Torque also seems extremely low for this setup. The last run we hooked up autotap and saw that there was negative timing. The dyno operator said this was the first time he's seen values in the negative. I've done research and seen that this is normal. The car did need a tune as the fuel trims are off. I would think there would be more power than this without a tune as well as no jagged line on the graph. The dyno operator said there was definately something wrong since this setup should give more power. I've also changed the spark plug wires twice already and would hate to do them again.
Registered User
Joined: Jul 2004
Posts: 371
From: Earth, Socal
Re: Dynoed car have problems.
Im gonna guess Opti on this one... Looks like a big ignition problem.. If you have the money, I would step up to the delteq or LTCC.
Good luck though... I know what its like to have the potential to make tons of power and not make anything near what you should!
See Ya!
Good luck though... I know what its like to have the potential to make tons of power and not make anything near what you should!
See Ya!
Thread Starter
Registered User
Joined: Sep 2002
Posts: 214
From: Hayward, CA
Re: Dynoed car have problems.
I do have the LT4 Knock Module. I was thinking maybe I should change the knock sensor at the bottom of the block and possibly switch out the opti. Anyone have anything else to add or possibly a diagnosis. The other weird thing is the torque curve looks ok in the beginning but I would think it should be higher.
Registered User
Joined: Mar 2002
Posts: 4,827
From: Waynesboro, PA
Re: Dynoed car have problems.
Looking at it, your power curve starts to break up at about 4500 RPM. I'd personally be suspect of the coil.
About the TQ numbers, I'm curious, is your car an Auto or a Six Speed?? If it's an auto, you could be blowing right through the convertor, I've seen it happen before. May be time for a new one.
About the TQ numbers, I'm curious, is your car an Auto or a Six Speed?? If it's an auto, you could be blowing right through the convertor, I've seen it happen before. May be time for a new one.
Thread Starter
Registered User
Joined: Sep 2002
Posts: 214
From: Hayward, CA
Re: Dynoed car have problems.
The car is a 6 speed manual tranny with about 102,000 miles. So the knock sensor shouldn't be the problem? I'm just wondering if the torque curve should start higher, I was hoping for around 350 ft/lbs. Its not even close to that. As for the fuel pressure, how do I check that? Just hook up a fuel pressure gauge? Wheres a cheap place to get one and how can I check at WOT? Thanks for the help guys.
Thread Starter
Registered User
Joined: Sep 2002
Posts: 214
From: Hayward, CA
Re: Dynoed car have problems.
I do have money for a new opti setup...but what is the suggested route to go with? Any links to something that might help...I've been reading up on the stage 2 Delteq I believe. I was getting around -20(+) or so degrees of spark retard at WOT. Not sure what the spark retard should be at WOT or at a particular RPM. I do have the obd2.com software for logging but no laptop...long story. I'll try to get one and see what it says for sure. But if someone could tell me what the spark retard should be at that will help a lot. If that is the problem what could the possible solutions be?
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Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
Re: Dynoed car have problems.
Do a search on the board and get the resistor # for the KR and put it inline to your computer. You are probably getting false knock,and it is pulling timing.There are also articles on where to put the resistor and the Radio Shack part number.
Registered User
Joined: Feb 2001
Posts: 1,234
From: New Bern, NC USA
Re: Dynoed car have problems.
There should be no retard at any time. A few degrees can be expected due to false knock but when it gets to 20+, there is a problem.
I once got knock due to a chafed plug wire arcing to the block. Look over your wires even though you already changed them. It might help to look at them at night to see any arcing.
I would also stick another tune in it. Scan for any dtcs too. The knock sensor could be bad.
I once got knock due to a chafed plug wire arcing to the block. Look over your wires even though you already changed them. It might help to look at them at night to see any arcing.
I would also stick another tune in it. Scan for any dtcs too. The knock sensor could be bad.