added ls6 intake + 1.8 rockers/918 springs gained NOTHING at the track!
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added ls6 intake + 1.8 rockers/918 springs gained NOTHING at the track!
My air fuel was right at 12.8-12.9 entire run. IM so pissed. IM at 12.1. 2 weeks ago I ran 4 back to back 12.1s, today same thing w/ the above mods. WTF gives here?? air was very similar both days
check my log for runs/mods and conditions.
http://tech.cfbinc.com/dave/Vette/HP...slip%20log.xls
Dave
check my log for runs/mods and conditions.
http://tech.cfbinc.com/dave/Vette/HP...slip%20log.xls
Dave
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That is very odd. I gained about 2/10ths from 1.8 rockers & an LSX intake. Are you winding the motor out higher to take advantage of the new hp in the higher rpms? I changed my shift points from 5900 to 6300......
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HP = TQ*rpm/5252
342.72658035034272658035034272658=300*6000/5252
371.28712871287128712871287128713 = 300*6500/5252
Maybe you need to rev it a little more and take advantage of the flwo characterstics of the ls6 intake and rev it to 6500
342.72658035034272658035034272658=300*6000/5252
371.28712871287128712871287128713 = 300*6500/5252
Maybe you need to rev it a little more and take advantage of the flwo characterstics of the ls6 intake and rev it to 6500
#7
? The computer needs some time to learn the new airflow capabilities?
The other thing is: 918 springs won't get you any more power idle-6000. They prevent valve float and reliability problems with high lift.
1.7 to 1.8 isn't a huge ratio increase.
during the 1.8 rocker run you had slightly higher humidity and ambient temps , all that means you may not see better times for a 10-15 hp mod.
Later,
Mike
The other thing is: 918 springs won't get you any more power idle-6000. They prevent valve float and reliability problems with high lift.
1.7 to 1.8 isn't a huge ratio increase.
during the 1.8 rocker run you had slightly higher humidity and ambient temps , all that means you may not see better times for a 10-15 hp mod.
Later,
Mike
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the DA was better for most of the day today then last time out.my intake air temps were teh same as well. i know i wont see any hp from springs, the only reason i got em was because i had some valve float over 5500 on thursday so i figured i better get em in for saturday. Ive driven quite some time w/ the new combo and the Ltrims are 0 at WOT and my a/f ratio is dead on so that is pretty much a moot point being an ecm issue.
Dave
Dave
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Because the valvetrain stuff should have upped your
peak flow(*) some, it gives you more usable upper RPM
and, when you shift from a higher RPM you also shift
-to- an RPM where you are making more power, next.
Now, I recall seeing where stock LS1 heads do'nt produce
any more flow at lifts over 0.550" (?). So the 1.8 rockers
might or might not actually do anything, if you are stock
heads and just increasing lift in a do-nothing regime. And
the high ratio rockers do nothing for duration while most
of the performance cams really fatten that out; double
whammy vs 6% "single whammy".
If your pushrods, springs and rockers are good for more
RPM then you might as well take full advantage of it.
Though where the line between advantage and pain lies,
I couldn't say.
peak flow(*) some, it gives you more usable upper RPM
and, when you shift from a higher RPM you also shift
-to- an RPM where you are making more power, next.
Now, I recall seeing where stock LS1 heads do'nt produce
any more flow at lifts over 0.550" (?). So the 1.8 rockers
might or might not actually do anything, if you are stock
heads and just increasing lift in a do-nothing regime. And
the high ratio rockers do nothing for duration while most
of the performance cams really fatten that out; double
whammy vs 6% "single whammy".
If your pushrods, springs and rockers are good for more
RPM then you might as well take full advantage of it.
Though where the line between advantage and pain lies,
I couldn't say.
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didnt think the heads might possibly be an issue. My max lift is now .529". So who knows, i ended up taking them back off as they are too loud for my tastes anyway. Maybe ill try the .1.85s at one point. Rockes are only an hour job anyway.
thanks
dave
thanks
dave