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Dyno Fright!


futurewa
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The car, once owned by WilliamsF1 (Ben), details here

Well, after enjoying the vehicle for two months on WA roads I've just had the car serviced. I asked for a dyno power run only to be informed that the car was running so lean and with so much advance in the timing that a proper power run would be dangerous. The car is now booked in for a day of tuning! This scared the shit out of me considering that the car has been driven reasonably hard since I bought it.

Ben (WilliamsF1) assures me that the car was tuned on RON98 (same fuel I'm using) by Jim at CRD and that it should not need retuning.

Below, is the Dyno run that supposedly shows shockingly lean fuel. As I'm not trained in tuning cars, your comments are appreciated. The car seems to run pretty well, so I'm loath to have it retuned unless really necessary.

dyno.jpg

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I think you are getting ripped off on the tune.

Have you asked the original tuner whether he tuned it that way or if it has changed afr? If it wasn't too long ago you might want a second tuner who is willing to listen for ping for you.

might check exhaust gas temps, is it overheating? What is your temp gauge showing? And if it isn't pinging, it may be fine, and just a really agressive fine tune!! with better fuel efficiency.

Ask the original tuner first, since you know it was Jim at CRD then call him and check if he did it that way and see if its ok to just leave as it is, since you don't want to waste money. He would be able to check the tuning chart for the car from the last time on his dyno.

In my oppinion it is probably ok, the boost isn't too high, just check for ping and watch the water temp gauge for signs of overheating.

Don't waste your money on another tune before you check out ping or knocking and at least see some signs of overheating.

have you done your own power run (accelerated all the way in third gear with the pedal to the floor up to 180kph), if nothing went wrong then you should be fine for a power run cause that is almost exactly the same thing just on the dyno.

Don't be scared to get a power run with that ratio, it isn't going to melt in the mere 30 seconds it takes!

It is unlikely to be overheating at this afr (you would notice it on your water temp guage) and it takes waaaay longer than 30 seconds to melt it, seriously go somewhere else (pay them) to listen for ping or knocking if its too advanced, you will HEAR it if there is a problem! Get your power run!

In general watch the water temp guage, that should do it but if you are still worried get an exhaust gas temp reading done. I think you are getting ripped off on the tune.

In general for everyone with concerns about tune should keep an eye on the water temp - if it goes above normal get it checked, if it goes redline turn off your car immediately!

If you were going for 14:1 ratio ie. very close to stoicmetric 14.7:1 (perfect burn) you might want to get a exhaust gas temp gauge.

Your tune is still sufficiently on the rich side to be safe so long as it is not pinging with that advanced timing.

DO NOT BE SCARED TO GET SOMEONE ELSE TO LISTEN FOR PINGING (to see if it is too advanced timing wize before you waste money on retuning it).

Lastly how the hell did they get that chart without doing a power run in the first place?

edit - I just had to add this - it looks like it was deliberately tuned for 13:1 and max fuel efficiency. It doesn't spike into lean ratio at all! And it makes sense to go up to 14.0 at off boost and idle speeds. And it looks like a low gear power run to me, couldn't have got the graph without one.

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I agree with edge's last comment, from the bit of the grapg I can see it was probably tuned to 12.8-13:1 down low, and almost certainly gets richer as the revs get higher.

it is leaner than many people would choose but not necessarily a disaster. You need to do and graph a full power run to see what it shows.

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I have seen many results of Jim's tuning, and I have never seen them run as lean as 13.x:1... That said, it's probably okay at low RPM, and you can see that it's getting richer very quickly. It's really at the mid-to-top end where you want it to run richer to protect the engine.

The other option is that the exhaust sensor that they throw into the end of the exhaust could be faulty, or thrown in sideways, or whatever.... and not reading accurately. The reason I say this is because of the rollercoaster AFR line. Jim's tunes usually result in very smooth and straight AFR lines.

Options from here:

Talk to Jim, ask for a copy of the dyno graph from when he tuned the car and compare them with this one.

Get another opinon (take it to another workshop in WA)

If the car is running fine, and you can't hear any detonation, chances are that it's okay. Don't rush into this and throw money at this guy.

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Agree with most of whats said. Contact Jim.

I'v known a few people to make HUGE gains from a CRD tune. He runs em lean with lots of advance in low load conditions; 1/2 throttle, low revs etc... so if your graph was wasnt done at WOT....

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Paid $36k for the car.

Just took the car out to warm her up with a few back to back acceleration runs and I saw75degrees on the Apexi FC Hand Controller, centre guage thermo sat 2 mil under the first line. Most I've seen on a really hot day with a little warmth in the engine is 78degrees. She takes ages to get warm and my 15 drive to work is not enough to get full temp.

I've run high revs in a top gear on 16 bounds of boost on a warm day, and she is still running mint, so I guess the engine is still ok.

Hmmmm. I'll call Jim on Monday.

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Your tuner is scared at 12lbs boost and 12.8afr??? wot da??

Even the factory ecu sometimes runs leaner at 4000 than that and then richens up towards the top end.

Bet he'll richen it up till it smokes like a diesel.... "yeah its nice and 'safe' now!!"

We regularly run circuit race engines at 13:1 AFR 20lbs boost 400kw and they dont melt...

The world is running out of oil....no need to waste it.

Find a tuner that knows more about tuning than a 'safe' 11:1 AFR.

cheers

Ben

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that dyno graph is absolutely shocking.

That AFR is all over the place, and it doesn't look like an experienced tuner has done that.

This is my AFR, after doing about 1 hour of 310rwkw ROAD tuning. And trust me, road tuning is much harder.

Its funny that people actually charge to do tunes that bad? How much was it? $600 - $800?

Oh, and some advice - I don't recommend ANYONE to run anything higher than 12.4:1 AFRs without water methanol injection.

Ignore the bit between 105kmph and 125kmph, as I was only tuning the top end for the dyno day that was on the next day. I have since made that full load AFR straight enough to put a ruler against.

314rwkw-2.jpg

Edited by The Mafia
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Ben spent a lot of money on that car, and used only the best engine and tuning workshops here in Sydney so you can have complete faith in what he told you.

I would be considering taking the car to another workshop.

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Ok, thanks guys.

The same workshop is running a Perth Dyno day in a couple of weeks. Is it worth putting the car in just to get the Dyno print out? If so, I can then see a complete graph perhaps at higher boost & revs. Considering the car has had the equivalent on the road, is it worth the risk?

Ben is going to send me the original graphs so I'll stick em up when I get them. I'll also call Jim at CRD.

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FUTUREWA its fine do not stress

MAFIA your is way to rich especially in the mid range

It says 12.4:1 to 12.6:1 in the mid range.... why do you think that is "way to rich"? If you thank that is way to rich, then you need to re-think your idea of tuning..

Seriously, a safe tune is 11.7:1 to about 12:1 afrs..

12.5:1 and above is considered very dangerous, but I can get away with it due to a fairly obvious reason - WMI

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AFR tuning is different from car to car - you can run some engines leaner than others it depends upon many factors - fuel density, chamber shape, piston dwell at TDC, piston diameter, spark plug postion, intake and exhuast design, exhaust backpressure - the list is endless. The main premisis behind AFR tuning is to find the minimum amount of fuel that reduces the onset of knock.

Edited by rob82
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It says 12.4:1 to 12.6:1 in the mid range.... why do you think that is "way to rich"? If you thank that is way to rich, then you need to re-think your idea of tuning..

Seriously, a safe tune is 11.7:1 to about 12:1 afrs..

12.5:1 and above is considered very dangerous, but I can get away with it due to a fairly obvious reason - WMI

im talking low to mid (75-108k's) to be exact... you could lean on yours at least a ratio in those initial dips safely.... as im guessing the a/fs are taken from the tailpipe and not the dump..

Your tuner is scared at 12lbs boost and 12.8afr??? wot da??

Even the factory ecu sometimes runs leaner at 4000 than that and then richens up towards the top end.

Bet he'll richen it up till it smokes like a diesel.... "yeah its nice and 'safe' now!!"

We regularly run circuit race engines at 13:1 AFR 20lbs boost 400kw and they dont melt...

The world is running out of oil....no need to waste it.

Find a tuner that knows more about tuning than a 'safe' 11:1 AFR.

cheers

Ben

^^^

that there is gospel...

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