Why is my 408 a dog down low?
Jan 16, 2007 | 04:23 PM
#101
Thread Starter
High on diesel fumes
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Joined: Mar 2005
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From: Phoenix, AZ
Thanks for the ideas guys! I'll check all this out when I get home. I need to do some more logging, I have a set of PID's set up to log EVERY spark PID there is. I tried it yesterday and didn't see anything, but I didn't look real close.
Jan 16, 2007 | 04:24 PM
#102
found this in hpt. The VCM constantly looks up both High Octane and Low Octane spark tables and interpolates a value between the two tables based on the current Knock Learn factor. If the engine has been operating for a moderate time without any Knock Retard then Knock Learn is zero and the interpolation favors the High Octane table, if Knock has been detected then the interpolation will move towards the Low Octane table. During MAF failure the Knock Learn is set to maximum and the Low Octane table is used. are your low and high octane tables the same?
Jan 17, 2007 | 11:43 PM
#104
Teching In
Joined: Jan 2007
Posts: 17
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What is your combo? Are all your parts & mods matched?
If they are, you'll just need a converter, if not back to the drawing board.
When you build an engine all the parts need to work in harmony.
You can't take a race came that was meant to make power in the 4,000 - 7,000 range and put it in a engine that was built by GM techs to operate at idle - 5,000 rpm. Same with everthing else if you have a full blown race engine and the thing is set up to make power in the 4,000 - 7,000 range and you drop a stock cam in it it won't run worth crap! Get it?
If they are, you'll just need a converter, if not back to the drawing board.
When you build an engine all the parts need to work in harmony.
You can't take a race came that was meant to make power in the 4,000 - 7,000 range and put it in a engine that was built by GM techs to operate at idle - 5,000 rpm. Same with everthing else if you have a full blown race engine and the thing is set up to make power in the 4,000 - 7,000 range and you drop a stock cam in it it won't run worth crap! Get it?
Jan 18, 2007 | 12:29 AM
#106
Originally Posted by Ascrap2003
What is your combo? Are all your parts & mods matched?
If they are, you'll just need a converter, if not back to the drawing board.
When you build an engine all the parts need to work in harmony.
You can't take a race came that was meant to make power in the 4,000 - 7,000 range and put it in a engine that was built by GM techs to operate at idle - 5,000 rpm. Same with everthing else if you have a full blown race engine and the thing is set up to make power in the 4,000 - 7,000 range and you drop a stock cam in it it won't run worth crap! Get it?
If they are, you'll just need a converter, if not back to the drawing board.
When you build an engine all the parts need to work in harmony.
You can't take a race came that was meant to make power in the 4,000 - 7,000 range and put it in a engine that was built by GM techs to operate at idle - 5,000 rpm. Same with everthing else if you have a full blown race engine and the thing is set up to make power in the 4,000 - 7,000 range and you drop a stock cam in it it won't run worth crap! Get it?
No LS1 based engine is built to operate only till 5k rpms. Sure everything has to be compliable together, but your theory is for the most part outdated.
Jan 18, 2007 | 09:51 AM
#107
Thread Starter
High on diesel fumes
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From: Phoenix, AZ
I said it earlier in the thread, but the cam I have in there was designed to make power from about 2100-just over 6000 RPM, which is exactly what I wanted and exactly where I'm planning on running the motor.
As far as the timing issue goes, I got it figured out with the help of dc_justin and XLR8NSS.
https://www.performancetrucks.net/fo...d.php?t=383764
Now I gotta mess with the timing table some more, but I think it's going to wake up nicely. I just added 2* of timing when stalling up and now the tires try to spin while I'm sitting still. No KR, so I'm going to keep adding away.
As far as the timing issue goes, I got it figured out with the help of dc_justin and XLR8NSS.
https://www.performancetrucks.net/fo...d.php?t=383764
Now I gotta mess with the timing table some more, but I think it's going to wake up nicely. I just added 2* of timing when stalling up and now the tires try to spin while I'm sitting still. No KR, so I'm going to keep adding away.
