My Rolling road result - diagnosis?

[Kalle]

Took my facelift Legnum Type V (auto) to a rolling road and got some dissapointing results..

I have read the following threads:

http://www.clubvr4.com/forum/showthread.php?t=23431&page=2&highlight=rolling+road

http://www.clubvr4.com/forum/showthread.php?t=24608&page=2&highlight=dyno

http://www.clubvr4.com/forum/showthread.php?t=23350&page=3&highlight=dyno

Here is a picture of the sheet:
http://www.soederman.se/Leggie/dynoresult1.JPG
http://www.soederman.se/Leggie/dynoresult2.jpg

Other:
http://www.soederman.se/Leggie/rollingroad.JPG
http://www.soederman.se/Leggie/rollingroad.MOV (Quicktime, 20 MB)

Run 1:
147,6PS ATW /Grrr
237PS ATF (does not seem to be counting the same as I have read in the previous threads)

Run 2:
154,1PS ATW
234,9PS ATF (hmm more PS in this run ATW but lower PS ATF???)

Torque seems fine though.. max: 315Nm in both runs, with an average of 300Nm between 2400RPM and 5800RPM

Did both runs in 4th gear.

I have 3" exhaust all the way with a racecat, otherwise nothing is changed.

Why do I get these low numbers??

WTF happens at 5400 RPM in run 1???

[bradc]

In the first run at 5400rpm it looks like they lifted off the throttle, then hit it again or something like that. Strange.

The overall low power could be due to bad air/fuel ratio, the ecu being in safe mod, and low boost levels.

What octane are you running, do you have a cold air box, what boost levels are you running?

[Kalle]

Running on 98
No changes to boost (don't know what the previous owners have done though)
Don't have any boostcontroller.

Still have the original cold air box

[bradc]

ok, the only thing I could suggest would be to reset the ecu by disconnecting the battery, and trying again, but make sure you have a boost reading and an Air/Fuel reading done too

[Wodjno]

Does it make difference which gear the run is done in ??

As far as i know ! All the other RR Runs are done in 3rd ??



I think ??:thinking:

[Nutter_John]

On run 1 not sure what happend but i don't think he lifted as normaly you get a spike when they do that .
Does seem a little low as I work it out to be around 233 bhp , when a facelift should make around 260 or more .

Would suggest as brad says do an ecu reset and get them to log the afr .

[Nutter_John]

Does it make difference which gear the run is done in ??

As far as i know ! All the other RR Runs are done in 3rd ??

It does make a difference depending on the Rolling Road , for instance my local one uses 4th as it is the preffered one on it . where as the Dyno Dynamics ones try and calibrate to be between 60 and 90 mph on full chat

On an auto it would make a difference cos doesn't the TC lock up in fourth ???

[Wodjno]

It does make a difference depending on the Rolling Road , for instance my local one uses 4th as it is the preffered one on it . where as the Dyno Dynamics ones try and calibrate to be between 60 and 90 mph on full chat

On an auto it would make a difference cos doesn't the TC lock up in fourth ???

Yes TC locks up in 4th n 5th !

What gear was used at last RR Day ??

[bradc]

john - if you're in tip mode in 4th and floor it at 2000rpm, the torque converter jumps into play and the revs go up quite high. If you do the same thing at 4000rpm, the rev's don't go up at all, so I beleive that at some point it does lock up

[Wodjno]

WTF happens at 5400 RPM in run 1???

Without Boost and AFR data as a minimum to compare alongside your BHP, RPM and Torque graphs !! Theres no real way having any idea of what happened..

But there could have been a rise in boost or a change in AFR's ?? Either Leaner or Richer !

We don't know if your running normal AFR's or Richer than Normal ? Or even a lot Leaner than Normal ? Aso you could have a Boost leak or weak actuators or failing turbo's ????

But as i say ! Without more data, it can't be figured :inquisiti

You might have even started running on 6 Cylinders from 5400rpm :D

[Kenneth]

I don't see boost or AFR on the graphs?

A bit hard to make any observations without them, as both can influence the power output significantly.

The torque graph does indicate boost fluctuations though.

[Kalle]

Thanks for all your replys! :)

I do not think resetting the ECU will help since I have done it recently. I don't have TC on my Type V so 4th gear should not be a problem.

Thinking of doing a complete map at a lokal tuner. Or is it a bad idea before knowing what the fault is? Maybe it's better first to solve the problem, then to upgrade some parts (IC, BOV, Fuel pump, fpr and maybe some pipes for better breathing) and then do a map..

Will try to get boost and AFR readings later this summer. It was only like 45£ so I won't be ruined :)

[Kenneth]

I would say best to get AFR and Boost graphs so you know where to look.

Could be something really simple like a tired BOV not allowing you to hold boost... dickytim had this and he noticed the improvement immediately after fitting an after market recirculating BOV.

AFR is important also, as you could see if the MAF adjustment would be dangerous or not. (If you haven't done it already)

In my opinion, it is always best to start mods from a known state of correct operation. This way if something misbehaves you know it was something you have done, and can un-do what you did to see if it comes right again.

[VR4 MAD]

AFR is important also, as you could see if the MAF adjustment would be dangerous or not. (If you haven't done it already).

What's this......."MAF adjustment"........am I missing something here. :speechles

Kenneth, please elaborate for the unnatually stupid........namely me. /pan /pan

I'm sure everyone elso knows what you mean............but errr........I don't understand what's being adjusted here and how. /Grrr

Sorry.

/toycar

[Kenneth]

What's this......."MAF adjustment"........am I missing something here. :speechles

Kenneth, please elaborate for the unnatually stupid........namely me. /pan /pan

I'm sure everyone elso knows what you mean............but errr........I don't understand what's being adjusted here and how. /Grrr

Sorry.

/toycar

The MAF has an adjustment screw at the bottom (covered by silicone unless someone has played with it already). If you look through the maf you will see that as it winds in/out it raises/lowers a blockage in the un-metered part of the MAF.

The MAF works by metering a certain per cent of the air passing through. This number combined with the un-metered part make the MAF calibration.

The ECU has a fixed calibration for the MAF, this means that if the air that is metered in the MAF is above a certain per cent of the total air passing through, then the AFR will be rich. (If below it will run lean)

Due to the nature of the MAF, it tends to run this way (and it is safer)
So you can usually safely wind out the adjustment screw and lean the mixture out a bit.

[VR4 MAD]

Cheers for that Kenneth.

Yea, have read about that screw on here before now that you mention it.

It's a bit of an 'un-official' adjustment screw then.............. :evilgrin:

/toycar

[Eurospec]

You cant really say what has gone on there without the boost and afr curves.

I ran my 7g vr4 on the dyno last night and i will try to post the graphs later, as you will see how much more can be told when you have the boost and afr info.

Bottom line it made 154bhp at the wheels (its an auto) but the boost dropped right off (0.3bar only) after about 4k, and the afr took a nose dive and dissapeared off the bottom of the graph! So now i know the car is running very rich, and it isnt holding boost, so at least i know where to start looking.

Cheers,

Ben.

[djwarden]

Does it make difference which gear the run is done in ??

As far as i know ! All the other RR Runs are done in 3rd ??



I think ??:thinking:

Yes it does make a difference which gear the car is dyno'd in. When I had my prelude i dyno'd it in 4th and got much better results than in 3rd but an S2000 owner (it was a Honda Revolutions meet) got better results in 3rd than in 4th as the ratios are different/rally

[Kalle]

I was a little bit disapointed with the fault analysis made by the rolling road.. No nice curves of AFR and boost.. just a single value of lambda at 4000RPM reading 0,681 (running a bit rich?)
HC 129
CO 11,8
CO2 7,33

boost was 0,6Bar at full throttle (manual reading)

So I guess there's some fault related to boost (it should be 0,8 or 0,9 for the facelift right?)

So first I will try to plug the BOV to see if I notice any differences. Any other suggestions other than getting a full graph over AFR, boost, BHP and torque?

[Kieran]

Your boost seems okay - Prefacelifts seem to be around 0.5/0.55, whereas post facelifts are around 0.7 as standard, so that is okay.

Your lambda readings... Assuming that VR-4 sensors have a typical voltage range( with 1 volt reading as 14.7 AFR), then your car would appear to be running too rich, but they do this anyway - the problem is that different sensors output different voltages for a given AFR, so although to me a lambda reading of 0.681 seems VERY rich - it could be normal - Can the rolling road not supply you with the reading as an AFR ratio, rather than a Lambda reading?

[Wodjno]

the problem is that different sensors output different voltages for a given AFR, so although to me a lambda reading of 0.681 seems VERY rich - it could be normal - Can the rolling road not supply you with the reading as an AFR ratio, rather than a Lambda reading?

0.681 is Very Standard fueling for a Standard VR4 at WOT

[Kieran]

0.681 is Very Standard fueling for a Standard VR4 at WOT

So .68 lambda is about 10:1 AFR for our sensors then?

[Wodjno]

So .68 lambda is about 10:1 AFR for our sensors then?

What i'm saying is that 10 AFR is normal for our cars at Wot.. Think i recall as low as 9.5 been logged at WOT.. 9.8 to 10.2 is factory standard..

[bradc]

To me it sounds as if an air fuel controller and increasing the boost would go a long way to getting good results.

[Kieran]

What i'm saying is that 10 AFR is normal for our cars at Wot..

Sure, I know that - what I'm asking is that does a lambda reading of 0.68 correlate to an AFR of 10:1? If it does, then I too agree that this reading is normal.

Thing is, if it is normal then it doesn't explain though why Kalle's wheel power readings are so low - standard prefacelifts usually manage around ~170ish ATW.

Mind you... having said all that - looking at this old post Kalle -

http://www.clubvr4.com/forum/showpost.php?p=150880&postcount=9

I notice (albeit with a Gtech) that you've recorded a 15.3 second 1/4 mile @ 95mph. This isn't too bad for a standard car - Maybe the rolling road hasn't given you an accurate power measurement?:inquisiti

[Wodjno]

Sure, I know that - what I'm asking is that does a lambda reading of 0.68 correlate to an AFR of 10:1? If it does, then I too agree that this reading is normal.



10.01 !

Basic Math ??

14.7 AFR x 0.681 = 10.0107 AFR /pan

[Kalle]

Sure, I know that - what I'm asking is that does a lambda reading of 0.68 correlate to an AFR of 10:1? If it does, then I too agree that this reading is normal.

Thing is, if it is normal then it doesn't explain though why Kalle's wheel power readings are so low - standard prefacelifts usually manage around ~170ish ATW.

Mind you... having said all that - looking at this old post Kalle -

http://www.clubvr4.com/forum/showpost.php?p=150880&postcount=9

I notice (albeit with a Gtech) that you've recorded a 15.3 second 1/4 mile @ 95mph. This isn't too bad for a standard car - Maybe the rolling road hasn't given you an accurate power measurement?:inquisiti

I got the same numbers later with a proper reading at 1/4 mile

[Kieran]

10.01 !

Basic Math ??

14.7 AFR x 0.681 = 10.0107 AFR /pan

Oh, I've learnt something today! Never thought of doing that! /thankyou

[Kieran]

I got the same numbers later with a proper reading at 1/4 mile

Well, assuming your car is standard, then this suggests all is about okay. Generally speaking, you can expect around 15 seconds out a VR-4, with up to 0.5 second either way, depending on the car and how well you get off the line. At Santa Pod, Wayne (white lightning) knocked 0.3 secs off by getting a good launch, for example.

I am thinking that maybe there's not too much wrong?:inquisiti

[Wodjno]

Well, assuming your car is standard, then this suggests all is about okay. Generally speaking, you can expect around 15 seconds out a VR-4, with up to 0.5 second either way, depending on the car and how well you get off the line. At Santa Pod, Wayne (white lightning) knocked 0.3 secs off by getting a good launch, for example.

I am thinking that maybe there's not too much wrong?:inquisiti


I agree with your thinking /yes

1 Mahoosive factor here is air temperature :)

Running at the Pod on a Warm June Day will deffo be slower than running on a Cool and Damp October morning, with the same car in the same state of tune /rally

Also air temp is a telling factor on a rolling road as well /yes

Especially with the OE IC..

I reckon you could probably see a difference of 20 bhp or more from a hot summers day to a cold winters day !

[Kalle]

But something must be wrong with that dip in the graph, right?



I bought an EVO6 BOV after reading somewhere here that it would fit the VR-4.

I realized today, when I tried to fit it, that it is not the same size.. :(
The Evo6 BOV has 25mm connections while the VR-4 BOV have 34mm connections /Grrr

Will try to use another rubber hose between the hose from the car and the EVO6 BOV. Or is that a bad idea? Everyone with a EVO6 BOV, how did you mount it?

The annoying thing is that the standard BOV broke at the vacuum connector, apperently the previous owner tried to glue it or something because it looks quite strange..

http://www.soederman.se/Leggie/BOV1.JPG
http://www.soederman.se/Leggie/BOV2.JPG

BTW which side is the inlet and which is the recirc?