just a question about dyno #s i got today

[03cobrateneight]

heres the story. i just put on ported eaton, billetflow throttle body, and plenum. im running a 2.8 pulley. prior to this i had mods in sig same pulley. was having small cut out problem under hard acceleration before, replaced clogged fuel filter before dyno today. heres where it goes south. before new mods put out 438 hp and around 490 tq in 100 degree weather. today its in the 60s here and i put out 380 hp and like 360 tq. im running 23* timing, 101 octane fuel and my air fuels were good all the way through pull. this has to be a dyno malfunction right :cryying: . one more question, at the end of the run clutch gave out. this clutch is less than 2 months old its a spec stage 2 i did not replace fly wheel at the time :bash: so i assume this is what is the problem my question is do you think iwill have to replace clutch and flywheel or just the flywheel? thanks for any tips in advance.
all pulls old and new on same mustang dyno
clutch did not give out till 1/4 mile runs on dyno seemed to be holding fine during hp pull

 

[knowfreed0m]

Ok definatly a dyno problem, does your car feel faster with the new mods?
Did you retune for the new mods at all?

What exactly happened with the clutch>?

I would sell it and get a DFX clutch kit with steel flywheel and new TOB and guide.

 

[03cobrateneight]

never got the car on the street however engine sounded and felt strong we did retune air fuels were off at first and we went from 21* to 23* of total timing
clutch felt fime during hp pull no slip tac seemed to climb normal however the dyno went through some weirdness and loaded my car hard a coupl of times when it should not have i think the flywheel got hot and glazed


last hp pull was good tac climbed fine dyn work good as far as loading the car but not sure about the #s

 

[knowfreed0m]

I would go to a diffrent dyno, can you post your graph by any chance?

 

[03cobrateneight]

i dont have graph left immedietly looking for clutch and flywheel car is still at dyno shop waiting on parts

 

[FireRed04Vert]

Maybe they changed the calibration on the dyno. I have to tell you....those numbers in your signature are WAY high for your mods on a properly calibrated Mustang. The second set of numbers sound more realistic...maybe a little low. Find a couple of shops that use a properly calibrated Mustang dyno and ask them what they see with your mods.

 

[racebronco2]

something is definitely wrong ... is it a stig ported blower .... who did the tuning ... preditor canned tune ?? .... first dyno tq numbers seem to high ... i would go to another dyno facility to get accurate numbers ... did you get your flywheel turned when you put in the clutch, you do not need to replace the flywheel when you replace the clutch .... as far as replacing the clutch the same time as the flywheel ... i would measure the thickness of the disc compare it to the old clutck and new clutch and decide from there .... if you did cause some wear do you really want to replace the clutch if it is worn too much ??????? .... i must disagree, a ported,tb and pulley should be more then 380hp

 

[03cobrateneight]

1st numbers dyno was working fine i dynoed gt shortly before all was good pretty close to factory and mine had mods on it cai exhaust underdrive pullies etc. numbers were barely above stock maybe 15-20 hp gain over stock. new car has custom sct tune while on the dyno af was great timing was great the new supercharger is apten stage 2 from a good friend (thanks steve youre the coolest) who dynoed 470 to rear with my setup on same dyno, we looked it up i didnt look at the torque numbers on his.

the dyno shop was great he even said the dyno had to be off on the hp due to a recent lightning storm but wasnt sure exactly what happened just has been having trouble since.

new clutch and pressure plate tob and flywheel on the way after car cooled down it drives again without slipping as long as i dont drive it too hard too long if i do it starts to slip during hard 1st and 2nd acceleration.

car runs like a raped ape now except now im getting torque management kicking in anyone know how to get that s**t stopped. thanks for all the advice one more question. my friend also let me use his billetflow throttlebody and it holds my rpm at 1500 at idle sometimes anyone know the fix to that?

 

[03cobrateneight]

also at the same time i did new mods i put in ngk tr6 plugs gapped at 25 the car ran like crap at low rpm so now i put in irridium 22's way better at low rpm again thanks to steve the local cobra guru