Stumbles at high rpm

Ok tonight I raced an srt-4... and is it just me or are those things really not that fast???

anyways... I noticed at about 4500rpm my car seemed to stumble a bit.. most noticeable in 2nd and 3rd gear. I just replaced my spark plugs, fuel filter, cap and rotor.. the only thing i didn't change was the spark plug wires because they seem to be ok. Would this be the first place to look?
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what plugs are you runnin? platinums are known to cause higher rpm breakup in SOME efi 5.0's.

might pull codes. things that come to mind are that your FP is on the way out and you leaned out. or the PIP or TFI are on the way out - both toss their cookies at higher RPM's, esp when hot.
my random thoughts.
good luck.
TFI's fail when they are hot and running at high RPM's.

Spark plug wires have two simple tests.
1.) Find a really dark place, crank the car up, open the hood and look for an electrical sparks show. No show, and the insulation is good.

2.) Use an Ohmmeter to measure the resistance of the wires. They should measure about 2000 ohms per foot of length. More that is a bad wire. Less that that is OK.
bigsparky said:
How can i check my FP without buying and installing a $100 guage.... and if it IS my FP.. how can i fix it?
by using a 30 dollar one. :)

i would go with what JR says. a parts store can bench test a TFI, but unless it happens to fail while testing (meaning it would probably need to be physically hot), the test is likely flawed. i bet JR has some ideas for ya. good luck.