34 replies to this topic

[rokkan]

Hello all, I'm after dome feedback on some rolling road runs. Hopefully I've attached two images below showing the results (from Europsec in Guildford). 
 
The car is a VXT, with a miltek system, airbox mod and an AMD remap. 
 
I bought the car earlier in the year and the previous owner had it re-mapped at AMD. At the time he posted the graph as it looked some-what strange and I was interested to find out what's what so I had it tested at Europsec (recommend via Back On Track).
 
So, in summary it does not look right. I've got the car already booked into Courtney at the end of the month to get it re-mapped but I'd like to get a sense of what could be going on. 
 
The car did multiple runs and only two are shown on the graphs. Peak power 194 at the flywheel (my understanding).
 
I'll answer any question I can with my limited knowledge. I guess what I'd like to do is as much pre-work as possible before the car gets to Courtney.
 
Mark

VX220 Rolling Road Eurospec p2 by mkr2009


VX220 Rolling Road Eurospec p1 by mkr2009

[Raptor]

I'll send you a separate PM but just briefly - do not necessarily trust the eurospec rolling road - I was there last Friday and my run is very suspect.. I believe it may be at least 40BHP down..  I am at Surrey RR tomorrow morning for a quick run.

Edited by Raptor, 30 August 2016 - 09:14 PM.

[rokkan]

Hello Raptor, I'll keep my eye open for your email. It could explain a lot but I'd be damn disappointed if that proves to be the case. I've not driven a standard turbo for a long time so I'm lacking a decent comparison for power outputs.

[Raptor]

PM Sent. - rolling roads are generally never consistent anyway and factors such as weather affects results but I'd guess you are at least 20 bhp down?

[Nev]

How sure are you that the tyres were not slipping? Thats the only way I can think the RR could error and show such a woefull mid range drop (regardless of +/- 40 BHP at the top end). Some RRs struggle to strap the car down successfully.

 

Edited by Nev, 30 August 2016 - 09:53 PM.

[Raptor]

In my case i asked if my tyres were slipping but was told deffo not. I hope to get a 2nd opinion tomorrow

Edited by Raptor, 30 August 2016 - 09:49 PM.

[Nev]

In my case i asked if my tyres were slipping but was told deffo not. I hope to get a 2nd opinion tomorrow

 

It might be a genuine car problem then, as such a mid range drop is not likely to be a RR fault IMO.

Edited by Nev, 30 August 2016 - 09:58 PM.

[Raptor]

Mark is there any way you can log intake temperatures? Looks a bit rich to me higher up but that could be due to the ecu pulling back if temps are going crazy.

[rokkan]

Hello Nev, I'm not sure at all about tyre slip - however Eurospec didn't mention any problems with slip after running the car. What we did discuss was whether the car was creating and holding sufficient boost (2nd graph). On the 1st run the car gets upto 1 bar but then falls away. On the 2nd run the boost starts at approx 0.7 but only gets upto 0.8. Mark

[Raptor]

In my case i asked if my tyres were slipping but was told deffo not. I hope to get a 2nd opinion tomorrow

  It might be a genuine breathing/engine problem then, as such a mid range drop is not likely to be a RR fault IMO.

Yep could be Nev. hence the 2nd rr opinion on a rr i trust.

[Nev]

It's common for cars to have severe undiagnosed problems (which are often easy to fix) but strangle power considerably. This is such a dramatically poor graph that I expect it will be easy to diagnose.

 

Edited by Nev, 30 August 2016 - 10:03 PM.

[rokkan]

Hello Raptor, I have OPCOMM but I'm not sure if it can log intake temps. I was going to log a couple of runs this week to see what useful data I could collect. When I was speaking to courtney they made me aware of the importance of inlet temps and keeping them under control. From what I mentioned over the phone, he thought it could be running rich. Not sure if relevant but I have been running the car on low octane fuel and the standard plugs (courtney have convinced me to run high octane stuff). Mark

[chickendippers]

Hello Raptor, I have OPCOMM but I'm not sure if it can log intake temps.

 

Yes intake temps is one of the parameters you can log on Op-com.

If you disable the majority of other parameters for logging too, it'll update a lot faster

[Nev]

I don't think IATs or rich mapping will explain that graph, as the effect is very severe and inconsistantly in the mid range.

 

I think it's far more likely to be some sort of failure to make boost or losing boost, possible things are sticking wastegate, cracked wastegate valve, bad solenoids, bad vaccuum pipes, bypass valve leaking, bad MAF sensor, bad MAP sensor etc etc.

 

Edited by Nev, 31 August 2016 - 05:45 AM.

[Raptor]

First thing i looked for was boost spikes based on that 2nd graph. Does the turbo engine have knock sensors?

[ayresyy]

 Yes there is a knock sensor, its also easy to check if its pulling timing due to the knock sensor using op-com.

[garyk220]

Looks like it is running way too rich past 4500 rpm on both runs,. This coincides with the big drop in torque from the same point. So it could be a dodgy map, but the inconsistent boost pressure on the runs points to a mechanical problem like those suggested by Nev.

 

Could also be the intake pipe collapsing under maximum boost pressure at mid revs and then partially opening up again as air flow picks up?

[badgerade]

I'll send you a separate PM but just briefly - do not necessarily trust the eurospec rolling road - I was there last Friday and my run is very suspect.. I believe it may be at least 40BHP down..  I am at Surrey RR tomorrow morning for a quick run.

 

Assume you told them what car you were taking?  I tried to get them to do a run for me but they told me they weren't happy to do VXs/Elises etc as they were too hard to strap down 

[Raptor]

 

I'll send you a separate PM but just briefly - do not necessarily trust the eurospec rolling road - I was there last Friday and my run is very suspect.. I believe it may be at least 40BHP down..  I am at Surrey RR tomorrow morning for a quick run.

 

Assume you told them what car you were taking?  I tried to get them to do a run for me but they told me they weren't happy to do VXs/Elises etc as they were too hard to strap down 

 

 

Yep - Charlie is OK with NA but has a problem with Turbo VX's for some reason.

[siztenboots]

the big drop to rich in AFR is the component protection map kicking in because the calculated EGT has gone too high.

 

the boost control looks like a failed actuator or solenoid

 

yes you can monitor intake air temp and pressure using OBD tools