Just Got Off The Dyno...

[lukes146]

Hey guys!

Just got off the dyno with the R33, and guess how much power it's making with front mount, 3.5" cat back exhuast, turbotech boost controller running 10psi and a high flow panel filter!

A quality 104rwkw!! WOO haha. Not really, actually quite frustrated Luckily we know the cause of the problem, it's running WAY too rich 11.4% or something if that makes sense to anyone, apparently it's meant to be at 14% (though i could be wrong with the % i think its actually a ratio of something) Whats funny is that i've told 2 mechanics already that it's running too rich and they've said it fine, I told this one and he decided he'd put my theory to the test and i was right, for once haha.

Hopefully it's going to only be the O2 sensor, i've just hit 40,000kms now and apparently they go every 40,000km. so right now it's making about 80kw less than what it should be! I just cant wait to get it running properly

On another note, after installing the turbotech ive noticed that when im on full boost and back the throttle off suddenly the needle hits like 15-20psi very very quickly and drops straight back, is that spiking, or just normal?

[Wink]

With your mods and running at 10psi no way should it be as low as 104rwkw.

The AFR you want is 12.

I suggest you get a picture of your dyno graph for us to look at.

[WazR32GTSt]

when you say 11.4% you mean the air to fuel ratio is 11.4

BUT... that is NOT the reason you are making only 104rwkw

i have an rb20det and with 10.5 AFR make 132rwkw. that is much more rich than you and more power also

i'd be looking at other reasons for your loww in power..

have you checked the timing?

cheers,

Warren.

[lordsnipe]

does it feel slow? 104rwkw would be a very sluggish r33...

[lukes146]

yeah thats it, the air to fuel ratio, im not sure what it is off boost but on boost its 11.4...I've only owned it for a month and from the moment i started driving it i've always thought it felt way too slow for what it is. So i asked a few mechanics, they drove it and said it was fine..Finally one knew what he was talking about!

It doesnt feel OVERLY slow though, but not quick by any means. I won't be able to get a copy of the dyno sheet until next week unfortunately, today was just a quick freeby 20min dyno run to fit the turbo tech.

I'm hoping theres nothing too wrong with it! what else could be causing a big loss in power, theres no wierd noises, its making proper boost, no leaks or anything..And no the timing hasnt been checked, i'll make a note for him to check that though.

cheers

Edited March 23, 2006 by lukes146

[WazR32GTSt]

when i first put my rb20 on the dyno, it only made 106rwkw.. it drove fine so i thought nothing of it

then i found out that the timing belt was on tooth out on the intake side!

the CAS (thing on the front of the engine that controls timing) had been wound around fully to compensate, so the car drove ok and i never knew until i played around with the timing.. it pinged when the CAS was set to the centre...

if a memchanic checks the timing he could identify this straight away (hopefully)..

of course, this may not be your problem, i am just sharing my experience in the faint hope that it might account for your lack of power

cheers,

Warren

[sl33ek]

i think at the very least you should be running 150rwkw with your mods

[MY33]

hey i had my R33 run on the dyno, and all i got is a 3.5" turbo back exhaust and a blitz pod and that came up wit 170rwkw. so i think that ya have a problem. goodluck wit it.

[RBFIRE]

my mod is similar to urs,

tho i dun have a FMIC, I got R34 intercooler, and split dump pipe,

I got 196kw, with AFR 11. at 10 PSI

Dyno varies but cant be that much different.

get ur 1 check, something isnt rite.

compression check maybe??? GL

Edited March 23, 2006 by RBFIRE

[MerlinTheHapyPig]

11.4:1 afr isn't too bad, it wouldn't explain the low power reading, i wouldn't be too worried about running a bit rich, heaps better then running lean. Post a pic of your dyno chart with the AFR reading on it and we'll have a look

[Al]

If this tunner told you the AFR should be 14:1, piss him off and go elsewhere. My mate blew his GTR motor because the dyno person had no idea about turbo engines and thought 14:1 was normal.

With a whole bunch of mods my car has a AFR that hovers around 11.2:1 and makes 274rwkw. Even though it kill a little power, it is better to be safe. The AFR you have is definately not the reason for the low power figure, get a second run on another dyno.

[lukes146]

ah thanks for the advice boys, i'm going to go to RX Engineering here in Newcastle, they have a pretty big rep so hopefully they can sort it out, hopefully my wallet can too lol.

Cheers..

Luke

[MerlinTheHapyPig]

generally N/A motors can be tuned leaner, around 13-14, but for turbo's you generally aim at around 12 or slightly richer.

if your tuner thinks 14 is an ideal af ratio ask him if he'll replace the motor when it blows up...

Edited March 23, 2006 by MerlinTheHapyPig

[chrissso]

Are you getting 11.4 AFR on wide open throttle? Or just crusing and Idle? 11.4 on full power is not bad. However, 11.4 at cruising is rich.

Pretty much what ^^^ said

[TTT]

new O2 sensor will fix nothing on your car

[Interloper]

If this tunner told you the AFR should be 14:1, piss him off and go elsewhere. My mate blew his GTR motor because the dyno person had no idea about turbo engines and thought 14:1 was normal.

lol, Al. Who was this dyno operator? and i blame you for not pointing your mate in the right direction

poor Rb26

[Mr Italy!]

The motor's shagged, get a compression test and leakdown test done and see what conditions she's in...

Might be time to start saving for a rebuild.

Correct me if im wrong but isnt this the car that recorded a 190rwkw on the dyno, and this year its down to 104rwkw... ouchie.

[Al]

lol, Al. Who was this dyno operator? and i blame you for not pointing your mate in the right direction

poor Rb26

A un-named guy who is a gun when tunning commo's, but obviously doesn't know shit about forced induction. I was not aware of the dyno runs till it was too late, and the owner should have known better himself .

Poor, previously health, original N1 block

[morlock]

new O2 sensor will fix nothing on your car

Actually if the O2 sensor is faulty then it will cause the ECU to dump a load of fuel in and make it run very rich.

Happend to my car and could feel a dramatic loss of power.

However if the AFR's are within acceptable range and the car revs out cleanly during dyno runs and car still makes no power then it is likely something more terminal.

[MerlinTheHapyPig]

The o2 sensor is only used in closed loop mode, i.e. when cruising. It won't explain a lower than normal dyno result.