BSR Stage 3 Boost?

[irf]

seems soooo obvious now lol

[pyaap]

Originally Posted by NarkyMark

No why?

Just curious because for the majority of rolling roads, power runs are done in 4th gear. The last time I had my car run on a Dyno Dynamics RR, it too was run in 3rd gear but refused to make more than 1.55bar boost which resulted in an extremely rich AFR and hence much lower power figures than expected; as a matter of fact it was over 40bhp down from the figure I had obtained from another outfit round the corner just a couple of hours earlier!! When the car came off the dyno, back on the road, it instantly made the 1.8bar it normally does, so something was not quite right with the run. When I asked why the run was done in 3rd gear, I was told that in "shootout mode" Dyno Dynamics stipulate the run must be done in 3rd gear, with tyres inflated to 50psi etc., because the data acquisition software had been calibrated for and demanded that certain variables be adhered to for consistency. For me, consistency and accuracy (within reason) are two completely different things (cue systematic errors etc.) so whilst I'm not stating that Dyno Dynamics RRs are unreliable, for my car in particular, I've not had a proper technical explanation as to why we encountered the scenario which we did.

[NarkyMark]

Originally Posted by pyaap

Just curious because for the majority of rolling roads, power runs are done in 4th gear. The last time I had my car run on a Dyno Dynamics RR, it too was run in 3rd gear but refused to make more than 1.55bar boost which resulted in an extremely rich AFR and hence much lower power figures than expected; as a matter of fact it was over 40bhp down from the figure I had obtained from another outfit round the corner just a couple of hours earlier!! When the car came off the dyno, back on the road, it instantly made the 1.8bar it normally does, so something was not quite right with the run. When I asked why the run was done in 3rd gear, I was told that in "shootout mode" Dyno Dynamics stipulate the run must be done in 3rd gear, with tyres inflated to 50psi etc., because the data acquisition software had been calibrated for and demanded that certain variables be adhered to for consistency. For me, consistency and accuracy (within reason) are two completely different things (cue systematic errors etc.) so whilst I'm not stating that Dyno Dynamics RRs are unreliable, for my car in particular, I've not had a proper technical explanation as to why we encountered the scenario which we did.

Thanks for that info!
Funny you should say this as the car does drive lovely on the road although the boost figures do match what the Dyno says, I have noticed that in 4th/5th gear, on the road, the car does seem to sustain slightly higher boost momentarily, but seems then to gently slip back to a boost it can attain around 13psi under WOT....

Anyhow I have ordered all new silicone vac hoses. As my motor is the 4 hose version for the Turbo/Intercooler side, I am going to measure the sizes needed and order the bits separately, as I can't seem to find the 4 hose kit available in the UK? Only the 5 hose kit, with the extra pipe near the Throttle Body...And the pipes on the 5 hose kit look slightly different shapes/lengths too, (so I don't think I could just buy this one and then disregard the 5th pipe?) Maybe some could advise me on this?


Edit:
My pipework configuration:

[foggyjames]

Ashok - why was your car running rich with lower boost pressure? Surely that shouldn't happen if it's mapped correctly. As I explained last time I saw you, you should know my tongue is firmly in my cheek when I talk about things being mapped correctly...

280lbft / 230bhp sounds like a major imbalance to me...i.e. torque is probably about right, but peak horsepower is down significantly. On that basis, we're looking for something which will compromise output at high RPM, but not in the midrange. That could be a lot of things...but it's a starting point. I prescribe a healthy 'stage 0'!

cheers

James

[NarkyMark]

Originally Posted by foggyjames

Ashok - why was your car running rich with lower boost pressure? Surely that shouldn't happen if it's mapped correctly. As I explained last time I saw you, you should know my tongue is firmly in my cheek when I talk about things being mapped correctly...

280lbft / 230bhp sounds like a major imbalance to me...i.e. torque is probably about right, but peak horsepower is down significantly. On that basis, we're looking for something which will compromise output at high RPM, but not in the midrange. That could be a lot of things...but it's a starting point. I prescribe a healthy 'stage 0'!

cheers

James

Sorry Bud but who the hell is Ashok and who the hell are you?
think you're getting me mixed up with someone else, as I ain't met and spoke to anyone to do with my Volvo, only the guy I bought it off and the guy who Dyno'd it!

Like I stated it's because it's low on boost it's running rich, (less air more fuel?)
Thanks for the info, either way....
Mark

[Nunchukhamster]

Originally Posted by NarkyMark

Sorry Bud but who the hell is Ashok and who the hell are you?

The forum member known as Pyaap is Ashok, one of the nicest, most helpful chaps you could ever meet

[NarkyMark]

Originally Posted by Nunchukhamster

The forum member known as Pyaap is Ashok, one of the nicest, most helpful chaps you could ever meet

Well surely he should know me not he then?

[pyaap]

Originally Posted by foggyjames

Ashok - why was your car running rich with lower boost pressure? Surely that shouldn't happen if it's mapped correctly.

Hi James,

Don't worry, the car's definitely correctly mapped and I'm in the process of composing a post to comment on the truly excellent service I received from MTE / Kalmar Union during their recent tuning visit.

Well, to best demonstrate the answer to your question, imagine disconnecting the electrical connector on the BCS/TCV on a T5 and then driving it at WOT. Undoubtedly, it will be making relatively little boost, will be running stupidly rich, and will be down on power. That is pretty much what happened to my car on the Dyno Dynamics dyno. I do not wish to go into the intricacies of the EMS2000 system because I do not wish to post up confidential information which MTE have shared with me. Now, if the car's mapped to run an AFR of say 0.8lambda at 1.8bar boost and with all other parameters being equal the car is only making 1.5bar boost, it will fuel the car more or less the same. The same amount of fuel with significantly less boost will result in an overly rich mixture and as I'm sure you're aware, that will compromise both power and torque, and possibly "bog" the engine down and possibly even cause it to misfire.

Now that is probably a gross oversimplification of what actually is going on but it is the most suitable analogy / explanation I can think of. For me, the bottom line is the dyno operator was unable to give me a proper technical explanation as to why the car refused to make full boost (be it load related or not) and also why it was that runs had to be done in 3rd gear (apart from "the software requires that").

[NarkyMark]

Got ya...Doh..I thought...Oh WTF....It doesn't matter...Sorry guys...my Bad!

[Engineer]

Here’s a few thoughts Ashok which won’t give any of Marco’s secrets away as they are mine when considering higher than normal output engines run on a chassis dyno the rollers can’t or are not set correctly to load the wheels during a shorter timed run which is normally the case the lower the gear and as all turbo engines rely on the correct load to develop max boost (not just ME7 or more up to date bus systems) not enabling max boost to be obtained could also cause a lower AFR to be recorded during a short timed run/span, as fuel is heavy compared to air the ECU calculates this and makes allowances so if the boost measured against absolute air pressure not gauge is not as expected it may be possible to catch the fuel map out be it open loop or a combination of both closed and open as on systems such as ME7. I can make my old girl do it on the road

As regards the T5 which is also failing to reach max boost on the road and also giving low bhp but good torque figures another thing to consider apart from those mentioned might be exhaust gas back up to the turbo turbine which will kill the max bhp but still give respectable torque figures.

Cheers