Area47

say you do a cam swap. stock push rods and ls9 springs. cam has .500 lift. nothing super crazy.

stock push rods. maybe 14k on the springs. what was noticed today after a couple wot runs on the data logger, it's down .03 or so on dyn & cyl/air. idc is down 1% and calc torque is down 10-15ft lbs.

idc was a consistant 86%
cyl/air was .96-.97 on a consistant basis.

zero has changed in the tune for three weeks.

my query being that the ramp rate of the cam being too aggressive for the ls9 springs has caused a weakening of the springs. no float, can spin to 6700 all day long and no float.

sand man

what motor is that ? how many miles? you know better then just leave those not mentioned
it might be as small as a dirty air filter BTW

Area47

i haven't cleaned the filter in 46k miles. so it may be time. thanks for that tid bit. it's a 6.2 with 47k on it. it just seems really odd that a sudden drop in the above mentioned seems more mechanical than anything else. unless it sucked a small bird in the air box.

sand man

get back to us when you clean the filter . better yet change it, I dont know about you but we have this happen all the time in the summer right after desert storms the filter just clogs up with dirt

Area47

filter is dirty, but can see light through it still. cleaned the maf. i seriously doubt it's the filter. im thinking more mechanical than anything else right now. unless im at the max air flow potential of the stock box itself.

springs are the first step though.

KLUG'S SS

iTrader: (6)

Pretty much same exact temp, humidity etc..... as when it was reading higher?

Area47

it was actually warmer out with less humidity the last time i logged some wot runs.

Gadgetized

iTrader: (9)

DA plays a big role too. Find an online DA calculator for the nearest dragstrip to you. Check the difference between both days of your dyno pulls.

Area47

i fully understand the concept of density altitude, however, this is more of an issue outside of the realm of simple air pressure differences, temp, humidity, so on and so forth. at least in my opinion it is. could be wrong, has happened before.

guess i can run down the process of elimination and see what comes up. imho it needs better springs with the cam that is in it. i also think the stock air box is limiting things right now as well. so we shall see/

nonnieselman

iTrader: (10)

i say new springs... wont hurt since your spinning it so high.