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thats a decent result, I got 250 on mine standard 6463. I think the rollers that I used are a bit suspect with the way the work out the power at the flywheel for a haldex equiped car. They were MAHA rollers,

never the less I'm happy with 250
 

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Discussion Starter · #6 ·
The power curve is lovely and smooth....

I am going to take a trip back to my local rolling road and get a post 6463 run...

That way we will all know if there is any improvement.
 

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take your cubic capacity (3.2l) times it by 75lbft/l and thats the max torque your engines going to make normally aspirated. If a dyno says more it's wrong.

So any dyno that says appreciable more than 240lb ft on an R32 is wrong.

If you don't believe me go and look at any engine from any manufacturer that makes appreciably more than 75lbft/l normally aspirated.

BMW's M series engines just break into the 80lbft/l but they spend huge amount of time and money making their heads flow extremely well.

Very high octane fuels will give a slight increase again toward the 80lbft/l region, or a major head job.
 

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Quote: posted by sutherlandm on 10/03/2005 12:26:05

Wilko "R32 hater(!!)" - True enough but the bhp figures are possible.

If the torque reads too high, power readings will also be high, as they're a function of torque.

I'm not an R32 hater, just a 'lack of understanding' hater.

R32's make 236hp. Period!

With electronic throttles, there are all kinds of tricks you can play to improve throttle response, and make a car feel faster.

Stick 3 degrees of timing advance in over VW's standard, and you might gain 5-10HP, but you'll get a lot more knock sensor activity.

De-restrict the intake and exhaust, and you may gain a few HP, but nothing huge, but you won't gain peak torque.

Same dyno, same day there was a TT with just a chip did 288hp. And an IHI ibeza that pretty much matched Jabbas figures. LOL.
 

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So are all these Dyno's wrong then?

Do they need you to recalibrate them all?

Where's a "proper" one?

Are your figures of a million horsepower actully right?

Does sticking a turbo on a car mean you can quote any bhp figure you fancy?

How come some cars have very low torque but high bhp and vice versa then if bhp is a fuction of torque?

The 6364 update cures an oversensitive knock control sensor - So the timing has not been advanced.

Basic questions following over complex answers.
 

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Quote: posted by Wilko on 10/03/2005 12:36:44

Quote: posted by sutherlandm on 10/03/2005 12:26:05

Wilko "R32 hater(!!)" - True enough but the bhp figures are possible.

R32's make 236hp. Period!

With electronic throttles, there are all kinds of tricks you can play to improve throttle response, and make a car feel faster.

Stick 3 degrees of timing advance in over VW's standard, and you might gain 5-10HP, but you'll get a lot more knock sensor activity.

De-restrict the intake and exhaust, and you may gain a few HP, but nothing huge, but you won't gain peak torque.

I agree with what your saying wilko but you have only told half the story about the ignition timing with a remap, what about adaptation on injection timing and how much adaptation the ecu is having to do to keep the engine as close perfect as possible surely this is as big if not bigger factor than timing

I pinched this from one of Uwes pieces on fuel trim here http://www.ttguy.com/maf-vag-com.html

"So, now that we know that the ECU wants to be able to control the A/F ratio. It has a prescribed set of values (maps) for a given RPM, Load, etc. So, the ECU tells the injectors to pulse for exactly XX.X milliseconds and that SHOULD get us the proper A/F ratio that we want. Well, if you tell an employee to go do something, you want to make sure they actually did it, right? The ECU has some snitches (the front O2 sensor and the MAF, for the most part) that will report back whether or not the desired mixture has been attained. The rear O2 sensor is used mostly to monitor the condition of the catalytic convertor, although in some applications it also contributes to trim information."
 

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Quote: posted by sutherlandm on 10/03/2005 12:50:07

So are all these Dyno's wrong then?

The vast majority of them, Yes!

Do they need you to recalibrate them all?

No. They just need to give standard figures, give or take, for standard cars to be believable.

Where's a "proper" one?

I believe VW have some rather accurate engine dynomometers at their factory.

Are your figures of a million horsepower actually right?

I don't claim a million horsepower, and am extremely skeptical of a lot of the big turbo kit makers claims. I just know that Subaru use my turbo on 300hp PPP'd stis. The limitation of the turbo is how much air it can move, and thus power it can make. From fairly extensive data logging I can tell you that I have maxed out this turbo, so all I claim is that the car is somewhere between 300 and 320hp.

Does sticking a turbo on a car mean you can quote any bhp figure you fancy?

No. It's just that torque is about airflow. You can only get so much air into a normally aspirated engine, and therefore maximum torque is fixed. Forced induction gives you the ability to effectively increase the cubic capacity of the engine to whatever the maximum airflow volume of the turbo dictates.

How come some cars have very low torque but high bhp and vice versa then if bhp is a function of torque?

As I've said torque is a function of cubic capacity. If you want to make high power from a normally aspirated engine, you have to increase it's volumetric efficiency at higher rpm's to produce peak torque at higher rpm, at the cost of low down torque.

All small engines producing high power have torque peaks at much higher engine speeds than the R32 does.

To improve volumetric efficiency, you need to keep pressure drop in the intake and exhaust system to an absolute minimum, and if you play with intake tract and exhaust length you can actually achieve slightly more than 100% VE. This is using the momentum of the air in the intake tract and gasses in the exhaust to effectively force air into the combustion chambers, instead of relying entirely on atmospheric pressure.

You might notice that most production engines other than highly tuned engines from Honda, BMW, Ferrari and a few others, all produce 75lbft/l and 75hp/l give or take.

This gives a tractable engine with a 6-6.5k redline that is flexible for normal drivers who don't want to rev the knackers off their cars.

Some examples

alfa 2.0lJTS engine 76lbft/l, 82hp/l. 16v variable valve timing, twin spark etc gets it to a little over 75hp/l

astons 6.0 v12 engine -70lbft/l, 75hp/l, big lazy low revving V12. Slightly down on torque but it's torque peak is produced low in the rev range.

Audis 2.0l fsi -74lbft/l, 74hp/l. Clever new FSI technology.

Bmw's 3.0l -74lbft/l, 77hp/l

Mercedes 3.2l - 72lbft/l, 68hp/l

I can't be bumd to pick any more for you, But do you see a pattern forming.

Now for the high revving screamers

Bmw M3 engine 84lbft/l, 107hp/l. Flat as a pancake until 5000rpm, them hold on.

Honda 2.0 (type R) 72.5 lbft/l, 98.5hp/l

ferrari 3.6l 76lbft/l, 111hp/l.

Now which of the two categories do you think the r32 engine falls into? Low revving plodder with a 6.5k rev limit, or high revving screamer with a 9K rev limit.

You might see how clever the M3 engine is now as well. Shame they go bang so often.

The 6364 update cures an oversensitive knock control sensor - So the timing has not been advanced.

If the update has gained any timing at all I will be surprised, especially if the cars are run on 98ron fuel. They will however have played with the throttle response and exhaust switchover valve to get rid of the odd torque dip in the mid range. Something the remappers did quite successfully.

Basic questions following over complex answers.

Simple questions, and fairly simple answers.
 

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Quote: posted by Wilko on 10/03/2005 12:36:44

Quote: posted by sutherlandm on 10/03/2005 12:26:05

Wilko "R32 hater(!!)" - True enough but the bhp figures are possible.

If the torque reads too high, power readings will also be high, as they're a function of torque.

I'm not an R32 hater, just a 'lack of understanding' hater.

R32's make 236hp. Period!

With electronic throttles, there are all kinds of tricks you can play to improve throttle response, and make a car feel faster.

Stick 3 degrees of timing advance in over VW's standard, and you might gain 5-10HP, but you'll get a lot more knock sensor activity.

De-restrict the intake and exhaust, and you may gain a few HP, but nothing huge, but you won't gain peak torque.

Same dyno, same day there was a TT with just a chip did 288hp. And an IHI ibeza that pretty much matched Jabbas figures. LOL.

Aren't you being a bit s elective with your pickings from that rolling road shoot out John

weren't there plenty of cars that made less than expected as well

how can you say its reading high when alot of cars got less than expected

wasn't that 288 an AMD car that could have something else done that he wasn't telling
 

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Quote: posted by andymac on 10/03/2005 13:07:29

I agree with what your saying wilko but you have only told half the story about the ignition timing with a remap, what about adaptation on injection timing and how much adaptation the ecu is having to do to keep the engine as close perfect as possible surely this is as big if not bigger factor than timing

I pinched this from one of Uwes pieces on fuel trim here http://www.ttguy.com/maf-vag-com.html

"So, now that we know that the ECU wants to be able to control the A/F ratio. It has a prescribed set of values (maps) for a given RPM, Load, etc. So, the ECU tells the injectors to pulse for exactly XX.X milliseconds and that SHOULD get us the proper A/F ratio that we want. Well, if you tell an employee to go do something, you want to make sure they actually did it, right? The ECU has some snitches (the front O2 sensor and the MAF, for the most part) that will report back whether or not the desired mixture has been attained. The rear O2 sensor is used mostly to monitor the condition of the catalytic convertor, although in some applications it also contributes to trim information."

ECU has a set of tables, at a certain measured airflow (maf) it knows it needs a certain amount of fuel to hit the required AF ratio for the prescribed engine load.

It uses the 02 sensors to keep this at 14.7:1 during cruising and light throttle openings to maintain maximum efficiency of the cat.

At high throttle openings, it uses airflow values to calculate injector period.

Because fuel varies slightly in density, and maf's go off and are not 100% accurate, though generally linear, the fuel trims are used to adjust for these variations.

The only other thing the ECU has to think about is spraying the fuel in while the intake valve is open.

Ignition timing is about how early the fuel air mixture is ignited, to make sure that the maximum pressure rise of the mixture occurs when it can be best utilised. Obviously if the piston is still rising, pressure rise would be a bad thing (knock)

The tick is to get the major pressure rise to happen as soon after TDC as possible, and to make sure that as much of theat pressure rise has occured before BDC.
 

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Quote: posted by LIAMH on 10/03/2005 13:38:54

Aren't you being a bit s elective with your pickings from that rolling road shoot out John

weren't there plenty of cars that made less than expected as well

how can you say its reading high when alot of cars got less than expected

wasn't that 288 an AMD car that could have something else done that he wasn't telling

Not realy Liam, most cars seemed to make good-high power figures, with just a couple with problems being low.

Some of the cars were run with too little load and produced low peak torque, with the torque peaks being too high in the rev range. Load based turbo ECU's need enough load to generate boost (torque), but this generaly doesn;t effect the peak power, as its produced at lower boost, high in the rev range.

Load would not effect a NA car though.
 

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here is the link to the wells lane RR day TOPIC from seatcupra

http://www.seatcupra.net/forums/showthread.php?t=51050&page=4&pp=20

the 288 bhp tt was an exception most recorded less than expected so i don't see how you can say just because the IHI made the same as Jabba

its reading high.... hows that work then

If anything there is an odd difference between the FWD remaped 225 engines and the 4wd.... with the 2wd cars recording lower than expected.... which makes the IHI result more impressive
 

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Not enough load on the FWD cars as I said.

IHI'd beeza runs a boost controller, so the ECU isn't controlling boost from the N75 anymore, so it's unaffected by load. Low load will have helped it out by minimising heat soak.

Some of the TT's were run with too little load also, which is why their torque peaks were too low, at too many revs. One curve I saw had peak torque at over 5000rpm.

All in all a bunch of dodgy results.
 
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