See this Dyno Sheet! Why does HP drop off at 5,200 RPM
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See this Dyno Sheet! Why does HP drop off at 5,200 RPM
This is a 98 WS6. Crane 1.8 rockers, pushrods, etc. this week
Z06 cluth assembly and hydraulics this week
LT Jet Hots and a true dual exhaust system.
I was told "The car had a spark knock, even though you could not here it much, so we tuned it to get the knock out."
Any idea on what's going on here? The car seems to have steady power now..but less of it.
Z06 cluth assembly and hydraulics this week
LT Jet Hots and a true dual exhaust system.
I was told "The car had a spark knock, even though you could not here it much, so we tuned it to get the knock out."
Any idea on what's going on here? The car seems to have steady power now..but less of it.
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Originally Posted by WS6FirebirdTA00
the high ratio rockers could be causing some valve float, valve float will look choppy kidna like what you have. whatn kinda springs u got?
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Originally Posted by Blacker
I am assuming a stock cam. In that case, they peak at 5200 rpm.
I can tell you this, when I picked up the car today I noticed in the first 4 blocks that it revs slower for sure. One other thing, in my garage when revving it up it backfires some. It has NEVER done that before. Aren't these signs of "excessive preload"?
Thanks for you help, really!
#12
[QUOTE=Mark A. Rogalski]
I was told "The car had a spark knock, even though you could not here it much, so we tuned it to get the knock out."
Any idea on what's going on here? The car seems to have steady power now..but less of it.
{QUOTE]
Put some timing back in the thing and richen it up to get rid of the "spark knock" they were talking about. All the symptoms you are talking about lead me to think it doesn't have enough timing.
Also be sure to check the actual timing with a light against what the datalog says your getting. Could be off somehow??
I was told "The car had a spark knock, even though you could not here it much, so we tuned it to get the knock out."
Any idea on what's going on here? The car seems to have steady power now..but less of it.
{QUOTE]
Put some timing back in the thing and richen it up to get rid of the "spark knock" they were talking about. All the symptoms you are talking about lead me to think it doesn't have enough timing.
Also be sure to check the actual timing with a light against what the datalog says your getting. Could be off somehow??