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Extremely nooby question, but just wondering if anyone can help me out here...
I ran what i thought was my stock 1989 NA6 at the V&E Rigoli dyno day yesterday and on a dyno that supposedly reads 'low' i got a whole 74.6kw, shouldnt it be closer to say 64? :S As far as I know the only engine/power mod that has been done to the car is a mania CAI and maybe a timing advance if im lucky (havent checked). The exhaust is completely stock, at first i thought it might be that my cat mightve been bashed out or something but i remembered me and a mate unbolted my cat back once upon a time to find it completely intact. I'm also that nooby that i cant tell the difference between a bp and b6 engine just by looking, and the stock bp should make around that much power if im not mistaken, but my engine code still reads b6 etc. :S I'm genuinely quite confused (and also pretty happy lol) as all I can think my engine would have would be the CAI and possible timing advance, and i cant see how it couldve resulted in a 10kw gain depending on how healthy my engine is...
any help would be appreciated as im thinking its the kind of thing theres an embarrasingly simple explanation for

for reference:

They may have had a special calibration that day to make you guys feel better lol

i have no idea about how dynos really work but could they have changed it for the one run somehow? my mates fd ran just before me and made 5-10 less than it did the last time it was on a dyno (155 vs 160+), and 2 evo 6s just before that made quite a bit less than what ive heard they normally do ('koval' should be around 400kw :S)

here's everyone if it makes a difference, im in the middle somewhere..

Was it a hot day?

If I remember correctly Turbo'd cars tend to be more fussy with air temp and power readings. SO maybe the runs in the past where they made extra were cooler days?


regardless, 74kw isn't that out there, Pamex's car made just under 70kw at RE Customs. (similar mods to you, mania intake, I think advanced timing?)

hmmm it was actually quite hot during the day but it went for quite awhile and by the time the fd was on it was cloudy, cold and raining.. if another car made similar power with similar mods then it makes it easier for me to believe my car could actually make that much power though haha because god knows i want to

naythan wrote:...i cant tell the difference between a bp and b6 engine just by looking, and the stock bp should make around that much power if im not mistaken, but my engine code still reads b6 etc.

Engine number commencing with B6... = 1.6 & BP... = 1.8.

FDs are very prone to heatsoak so 5-10kw loss isnt unexpected if it was a hotter day. My old FD posted 197kws and i thought that was ridiculously high until the other cars got on and all posted power figures in their correct ranges..

Finding the engine number can be a bit tricky if you don't know where to look. An easier way is to look for the crank angle sensor. Righthand drive cars for Australia: CAS on Driver side = 1.6L; CAS on passenger side = 1.8L. The photo below shows the CAS on my NA6 (1.6L engine). BTW, my car is 100% stock and it made 71rwkW on the dyno at MX-5 Mania a few years ago. An intake would be worth a few kWs I guess, so your 74.6rwkW isn't too unbelievable I suppose.

DSCF1384 by Guran5, on Flickr

Ive said it before and will say it again, dynos are BS 99% of the time. The last 1% is when they are used properly, by an experienced developer.

Dann

Shouldn't an NA6 have 87Kw?

GP wrote:Shouldn't an NA6 have 87Kw?

That would be at the engine.

Because Dyno's measure from the wheels power is always lower as some is absorbed along the way by gearbox/diff/wheels/tyres.

Part of the reason for Dann mentioning they're not particularly useful outside of tuning (and if you're comparing results from the same dyno, same day, same car)

I know that EEV000 EVO8 fairly well.
The 250ish it recorded is pretty close to the mark for it, so I don't really think there was much if any dyno trickery going on.
Looking at the sheet you posted, intake and ambient are pretty close too, so no trickery there either.

Admittedly, as you say it seems a little high, but not impossibly so.

As Nitrodann stated, they all read different, and ones that read properly are few and far between.

I would consider that 74kw on a stock NA6 to be on the high side. Thats about what a good stock NA8 makes on the dyno I use.

Cheers
Woz