Power Figure Issue

[lows_13]

I went to the 'Dyno B' and got my car

dyno'd. Except i only got about 163rwkw 'Dyno B', unlike 193rwkw which i got at 'Dyno A'.

The guys at 'Dyno B' said that peak power dropped off at about 5000rpm, when it actually

should still be increasing. The only thing i have changed since the first dyno was, i installed a S/S

inlet pipe between AFM & turbo.

The power curve was fine at 'Dyno A'. Have you ever come across this before?

Both dyno runs showed good AFR's.

What would be the more appropriate power output figure for my current mods.

Mods:-

1993 R32 Skyline

RB20DET

Stock internals

5-speed manual

R33 S1 turbo

Trust front mount intercooler

Full exhaust (Split 3' dump/front pipe)

GTR fuel pump

Boost controller running at 14psi

Re-mapped ECU

Air pod

S/S inlet pipe

Edited April 29, 2007 by lows_13

[paulr33]

163rwkw sounds realistic

lots of things can affect the readouts, post both dyno sheets

one could have air temp correction, the other might not

one could be in a different gear or different ramp rate etc

[Trav33]

Can you scan/photograph the two dyno charts + post them?

[T04GTR]

yeah.

mines ranged from 275 to 316 except on 316 i was running less boost lol. still gos hard thats all i care about

[lows_13]

I've got Dyno B's printout, but not Dyno A's printout.

I'll try and scan it and post it up.

Average temp on day of dyno run

Dyno A:- 30 degrees

Dyno B:- 10 degrees

[GTR1993]

dont worry about ambient temp, have a look what inlet temp is on the graph, if all the factors are displayed

[series2r33]

Dynos can be calibrated differently therefore showing that some cars have less powerful then they do on a different dyno. The stainless steel intake pipe shouldn't have made any difference as the only problem i've heard of is with the stock plastic one contracting under suction and limiting air flow so if anything the s/s one should be better. my suggestion would be to go back to dyno A and get a re-run on that

[lows_13]

I reckon i'll go back to Dyno A this weekend coming and try again.

One person has said that 163rwkw sounds more likely can anyone else confirm.

[mr_rbman]

looking at the rb20 mods section i would have guessed around the 180rwkw mark, everyone at 'dyno b' was reading low and i have heard 'dyno a' is a dyno thats known for reading a little high.

[Simon-S14]

most Rb20's with the 25 turbos make any where from 160 to 180 ish rwkw, even more if they are pushed to 14 psi. but for the sake of it we'll assume 12 or so psi.

dont be too fussed about different dyno reads out tho, does the car feel any different on road compared to both dynos?

[lows_13]

No i guess not, it would be nice to get an accurate idea of what power i'm producing though.

On both dyno runs i was running boost at 14 psi

[lows_13]

Here is the sheet from Dyno B's run.

They reckon that peak power was made at 5000rpm and then it droppped off......

Edited April 29, 2007 by lows_13

[Beer Baron]

maybe the stainless inlet pipe has made your car slower/less powerful? I mean if that's the only thing you've changed and your power has gone down... how does it feel to you?

[lows_13]

  Beer Baron said:

maybe the stainless inlet pipe has made your car slower/less powerful? I mean if that's the only thing you've changed and your power has gone down... how does it feel to you?

Power feels about the same after the S/S inlet mod.

Theres a lot more turbo sucking sound, thats about it.

[blind_elk]

The ambient temps clearly show the 2 runs weren't done on the same day, probably not even the same month! Is it any wonder then that you encountered differences. Although I would expect the colder day to produce better power.

Are both dynos the same model? Same manufacturer?

[lows_13]

The dyno sheet above is from 'Dyno B's' run.

2 consecutive runs about 30 seconds apart.

I havn't got a dyno print from 'Dyno A' that i can post up

[WazR32GTSt]

160rwkw sounds about right

[Lithium]

193rwkw sounds about right for those mods on a lot of the dynos you get over here - think of different dynos as different measurement standards. Stick to the same one and it SHOULD read the same.

[xRHETTx]

They say that each 3 degree increase in intake air temp makes a 1% reduction in power.

So for a 20 degree (at least) increase in temp thats probably 8% power just there, compounded by the hotter air going through the intercooler...

So more like 10-15% power drop from increased temp and your getting to be in the same ballpark kW reading.

Rhett

[Bumblebee]

im going with the 160 mark because near on 200kw? on 14psi with a tiny 2lt engine?? hahah no chance... not with a standard r33 turbo.. ive driven one of those b4 and damn they are torqueless and slow sorry dude but theres no chance urs makin near on 200rwkw