Unichip

[Darth Paul]

Interesting stuff Paul, how did you feel on that result?

PISSED.

I presume they used fans but still your going to lose some cold air flow compared to on the road.

They had an enormous fan blowing on the front of the car, and another blowing down into the engine bay.

How can there Dyno be out by 10% out? Why haven't they corrected it if they know it's out?

They said it's because they have hundreds of maps in there...

I'd be wary of how accurate that dyno is..  s:? :? s:?

Indeed.  s:? :? s:?   Now I want it on another rolling road, but I really don't want to fork out another £250...  s:x :x s:x

[markiii]

it won't cost you £250 just to get a dyno done, whether you decide it needs retuning or not will determine if it's that expensive.

was teh figure quoted at teh wheels or at teh crank?

[Darth Paul]

Crank.

[markiii]

I'd be expecting that kind of figure at teh wheels,

so assuming it was a true rolling road, are you sure they corrected the reading to get a true corrected reading?

[Darth Paul]

I'd be expecting that kind of figure at the wheels,

so assuming it was a true rolling road, are you sure they corrected the reading to get a true corrected reading?

Well, that's the 65,000 dollar question isn't it.  s:? :? s:?   When they first told me I thought it was at the wheels. I almost died when they said it was the crank.

[Anonymous]

My dyno is costing just £57 FYI

[Slacey]

My dyno is costing just £57 FYI

Yes, but Paul had his tuned as well which is where the extra cost came in.

[Anonymous]

Interesting stuff Paul, how did you feel on that result?

PISSED.

No wonder   s:cry: :cry: s:cry:

[GSB]

A fan into the engine bay is all very weel, but its not blowig air over the car at 120 mph, which is what it would be doing in the real world... I would guess that unless the fan blowing your engine bay was hurrican ivan, you'll be losing a little power due to the intake that would be restored under normal driving conditions...

I have to confess, at first glance those gains dont look that impressive, especially given the local METAR weather data for the morning you had it done gives an air temperature of only 1degC, and a pressure of 1024mBar. It  shows 100% humidity too, but I cant remember offhand how humidity effects performance of Naturally aspirated engines. Of course these figures refer to the outside world, what was the intake air temp on your engine at the time?

The bit that really spells it out for me though, is that fact that you mapped the car on 50/50 95-97 RON fuel... You'd have had far more impressive results running on 100% 97 RON. Still, you got 12bhp from a fairly crap mix of fuel, which can't be sniffed at...

Also, someone mentions tyre slip being a casue for losses on the dyno, I'm going to point out those bloody great wheels you have on there at the moment as a possible cause of further losses?

[markiii]

a very good point ref the wheels, howeverfor comparison I beleive they were exactly the same wheels that Martin had on when having his unichip dyno done.

which definately makes me wonder how they corrected for drivetrain losses.

Did they take any info specifically from your car? or do they have a stock assumption that they used.

[crankshaft]

Hi !

Mine was dynoed at 144bhp at the wheels before AND after fitting the UNICHIP, there was no noticable or measurable increase in BHP in fitting the UNICHIP, except for a tiny spike at near maximum RPM which could have been a glitch.

I have to point out however that these figures are taken at maximum throttle throughout the rev range, i.e. the engineer floors the accelarator and the curve is based on that as the engine works itself through the rev range.

I was hoping for a 5 - 10 BHP increase so was a bit disappointed when I did not see it. It does seem more driveable however with some improved low down torque !

Crankshaft

[GSB]

Another good point, many dyno operators "guestimate" transmission losses on the run down after a full power run, by measuring the amount of power required to drive the wheels with the rollers, its a shit way of doing things though...

The major problem with dyno's that no operator seems to ever explain to you, is that they dont actually measure horsepower. They measure speed, time, and torque applied to the rollers by the tractive effort of your tyres, and then calculate the amount of horsepower that would have been required to accelerate the rollers, or the amount of power required to apply a known torque value to the rollers. Both of these are dependant on your tyres and wheels for the transfer of force.

The only "real" way to interpret a dyno result is to forget the ultimate numbers and compare one run against another. You can then work out the % gains or losses between the 2 runs, and have a far better indication of whats going on...

[markiii]

so arguably that equates to anything betwen 12 and 14% increase and torque to match,

not so shabby after all.

ref teh intake and exhaust

TTE exhaust is purely a cosmetic mod, so no BHP here, figure on loosing 1BHP for the Apexi, though it's arguably worth it for teh noise.

[Darth Paul]

so arguably that equates to anything betwen 12 and 14% increase and torque to match,

not so shabby after all.

ref the intake and exhaust

TTE exhaust is purely a cosmetic mod, so no BHP here, figure on loosing 1BHP for the Apexi, though it's arguably worth it for the noise.

Yeah, I appreciate the 12-14% power gain. It's just I wanted a figure for 'pub talk'!  s:wink: :wink: s:wink:    s:oops: :oops: s:oops:

[GSB]

For a "pub talk" dyno figure, get the operator to stick the intake air measurement probe next to the exhaust manifold. When the software calculates "corrected" power (to ISO, SAE, or whatever other standard) you should have a nicley inflated power figur to impress all the guys in the pub with...

Personally though, I prefer to say I have "only" 138bhp, and the trounce every one of them one the drive home...  s:twisted: :twisted: s:twisted:

[MRMike]

This is exactly why I bought the Gtech.  Because you really can't guage anything by the numbers Dyno's put out, the difference is what's important, and as has been said 12-14% is significant.  If you really want a number for pub talk, why not work up 12-14% of 138 and add it. Admitedly you have no idea what it was putting out before, but at least you know what 'difference' it has made. To assume that your car was putting out the manufacturers BHP is a fairly safe assumption.

But I can imagine in the same situation that I'd be a bit annoyed with having a dyno session and not being any wiser after it. I would look at it this way, you had to have a dyno to map the car anyway.  You now know your car has 12-14% more power.

[Jap GT300]

So as an approximate start figure you are in the lead with 158 BHP

Time for everyone else to try and beat you

[Anonymous]

Indeed.  s:? :? s:?   Now I want it on another rolling road, but I really don't want to fork out another £250...  s:x :x s:x

it won't cost you £250 just to get a dyno done, whether you decide it needs retuning or not will determine if it's that expensive.

My dyno is costing just £57 FYI

Yes, but Paul had his tuned as well which is where the extra cost came in.

 s;) s;)

[Anonymous]

So as an approximate start figure you are in the lead with 158 BHP

Time for everyone else to try and beat you

How does that work?   s:?: :?: s:?:

[Darth Paul]

So as an approximate start figure you are in the lead with 158 BHP

Time for everyone else to try and beat you

How does that work?   s:?: :?: s:?:

Stock power + 138hp

14% of that is 20hp

Add them together.  s:wink: :wink: s:wink:

[Anonymous]

Yeah i got that much but where did the 12-14% come from?

[Anonymous]

Yeah but the engine power may not have been 138 BHP stock - power output can vary from engine to engine.

[Liz]

Did they not do a pre-chip dyno reading, the garage I am taking mine to said that they would do it? Or is that going to be extra!

[LeeUK]

I'm hoping to take mine to Millways in a few weeks time to get a proper dyno run, from what I've heard from speaking to them, these lads seem to be pretty clued up on both MR2's and Unichips.  Hopefully they'll get the most from what modifications I have already.  They can do 2 cars in a day if anyone wants to come with?   s:) s:)

[SimonC_Here]

When mine finally arrives (anyone from the "second" batch been asked for the rest of the payment yet?) I will be taking it to Millway hopefully. So I would be interested in how it goes for you.

Simon