Ltrim Spread and Variance? H/C Car?
05-26-2002, 03:24 PM
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Ltrim Spread and Variance? H/C Car? What are you guys seeing for Ltrims?
I'm seeing bank to bank differences of about 2.5% on average with occasionally up to 4%. On each bank, I'll also see the Ltrims vary by about 4-5%.
I need something to compare against! I don't think I have a mis-fire (I get the normal cam misfires at idle and an occasional series up to 14 or 15 at cruise on a couple of cylinders).
Thanks!
Mark
I'm seeing bank to bank differences of about 2.5% on average with occasionally up to 4%. On each bank, I'll also see the Ltrims vary by about 4-5%.
I need something to compare against! I don't think I have a mis-fire (I get the normal cam misfires at idle and an occasional series up to 14 or 15 at cruise on a couple of cylinders).
Thanks!
Mark
05-27-2002, 09:36 AM
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Re: Ltrim Spread and Variance? H/C Car? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Sparky:
<strong>I'm seeing bank to bank differences of about 2.5% on average with occasionally up to 4%. On each bank, I'll also see the Ltrims vary by about 4-5%.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">They should vary with rpm and engine load. Isn't the fuel pressure table a factor at a certain manifolfd pressure (or load)? I'll look a little closer, hope to do another tweak, #3, today. swapped in 42's into a f.i. engine. fwiw, found the predicted values from the widely circulated spreadsheet are very ballpark. shooting for values in the range of -3 to -1, and from what I've seen, you can't get a good across the board factor on one attempt, you need to tweak parts of the table. I suspect the tubos play havoc with this.
<strong>I'm seeing bank to bank differences of about 2.5% on average with occasionally up to 4%. On each bank, I'll also see the Ltrims vary by about 4-5%.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">They should vary with rpm and engine load. Isn't the fuel pressure table a factor at a certain manifolfd pressure (or load)? I'll look a little closer, hope to do another tweak, #3, today. swapped in 42's into a f.i. engine. fwiw, found the predicted values from the widely circulated spreadsheet are very ballpark. shooting for values in the range of -3 to -1, and from what I've seen, you can't get a good across the board factor on one attempt, you need to tweak parts of the table. I suspect the tubos play havoc with this.
