UsmcMustang

allright let me tell you about my mods and what the problem is

5.1 l 3v - comp cams stage 2 nsr
- bbk long tube headers
- livernoise cam phaser with lock outs
- bbk high flow cats
- flowmaster outlaw axel backs
saleen cold air
- msd coil on plugs
- fresh spark plugs ( motorcraft )

so previously i was dynoed in california at 91 octane at 358 . rwhp

fast forward i now live in northern va , got my car to a show and wanted to have it retuned for 93 octane
i was sitting at 300 rwhp when i came in left at 307 rwhp ??

what could the loss of power be , my tuner guy says that number of 358 is resonable but he doesnt know why im so short of it . i did the ghetto way to do a compression check ( by disconnecting the coil on oplugs a cylinder at a time ) and it seemed to be fine , this is a low compression block with dish pistons , im trieng to get ready for a kb supercharger , right now all i need is that tr- 6060


the 5.1l is a coast high perf block , iron block



so does anyone have an idea , i know the temperature does make a difference but not over 50 rwhp ( it is hot as hell and humid )

so i m in need of some advice my tuner guy doesnt know either why im not able to get those numbers

im getting depressed by this car , if i didnt have my 67 pontriac project i would trade my 07 in , i do love her but it so frustrating

S197GT07

A dyno is just a tool, and you can manipulate a dyno to read whatever you want it too.

Does the car FEEL like its down 50hp? You would be able to notice.

Take dyno numbers with a grain of salt.

UsmcMustang

i am worried that my engine is having problems the dyno the new shop uses is a dyno jet , the other shop used an dyno dynamics , i have heard some dynos producing lower numbers but not this low

S197GT07

Again, its just a TOOL! Does the car feel like its down on power?

I can manipulate a dyno to say you have 30hp, or 3000. If the car feels fine, and isn't throwing any codes, you're probably going to be OK.

You can datalog to make sure

UsmcMustang

the car doesnt feel any different , but there is something wrong with it , it dies sometimes while in traffic and sometimes goes into limp mode but no codes so im thinking i have floating valves

S197GT07

Sounds like a tune issue.