960 replies to this topic

[CHILL Gone DUTCH]

The reason Haggis flows well is because of the additional porting. Vocky only did a mild port of the exhaust side on your Saab head. With additional porting of both the inlet and exhaust it would flow much better.

Yep when I go to see vocky next possibly to have chains done and checked ( 2 years I think at least ) I will speak to him about opening up more on the inlet side and maybe a touch more on the exhaust side as I have some very big primaries on the exhaust which is a bit wasted at moment

[The Batman]

You want them to be gasket matches

[siztenboots]

it would be interesting to see how different the compression of the 2.2 and 2.0 (saab and z20let) compare with the target lambda and ignition. do the saab heads have better exhaust valves, or better head cooling?

[Exmantaa]

 

 

  nobody in there right mind would put the time in that i seem to   

  That's because it is not really clear how much wiggle room there is between a basemap and your optimised one. NO ONE has pulled so much out of the 80mm as you have, which paves the road of what can be done, besides chucking on silly pullies.    

It's very difficult to pick out what is false knock from road and bangs and what is engine ping/ knock As the knock sensor basically pics it all up What is very good if your in doubt and I'm now using more and more is after adding ignition and optimising it I go and do a full fuel learn session and tick the knock box on the table and see what is being picked up more often as it can be a little temperamental in the power runs Also to watch out for if the Ecu does pick up knock when you process the measurement it pulls that area of ignition extremely low which then you have build it back up again I have found very little knock being picked up in these sessions compared with the power runs and using this has gave me a lot more confidence with in adding the ignition It's also worth saying o think adding ignition in areas is a waste of time as power is not increased And this is why my ignition runs in waves rather than linear I've spoke briefly to frank about this as his runs very linear compared to mine but I have concentrated almost a figure at a time in the ignition tables which is very time consuming It quite interesting that the knock that I do pick up in the learn sessions is from areas with relativity low ignition to start with 15-17 degrees So I think these setting are far to low especially for my engine

 

 

As you are finding; optimizing ignition is very time consuming and quite difficult on the road. But I have to say that my 2.0 (LSJ) ignition settings are far from optimised, as I only removed possible knock areas's and then hand smoothed the timing table.

Really the best to do this is on a brake dyno where you can fix the revs and simply search for max torque by live altering the ignition. (OBD should be able to do this) Much quicker and safer process. And probably cheaper too in the end with less fuel bills.

 

Regarding the head porting; there is not much to win with inlet porting as they are pretty big. And you can mess up the low/midrange if you port that wrongly... Stock exhaust ports are really tiny for an SC and the throat area needs a lot of work. Hogging out the gasket side is not enough.

 

PS; I have an E85 pump at 3km from my house. Really want to try that once, as the Harrop seems to love the corn juice.  

[Exmantaa]

 

The reason Haggis flows well is because of the additional porting. Vocky only did a mild port of the exhaust side on your Saab head. With additional porting of both the inlet and exhaust it would flow much better.

Yep when I go to see vocky next possibly to have chains done and checked ( 2 years I think at least ) I will speak to him about opening up more on the inlet side and maybe a touch more on the exhaust side as I have some very big primaries on the exhaust which is a bit wasted at moment

 

 

Ehhh... This is a bit in contradiction with the too-much-power statement and possible going back to the M62 charger...

 

Fit better tires and if it's still overpowering you; go and book Spa.

[CHILL Gone DUTCH]

Was thinking about trying to reduce the manifold pressure I suppose all this will do is move the pressure on to the valves Surely there would be advantages even when I go back to m62

Edited by CHILL Gone DUTCH, 29 March 2016 - 12:07 PM.

[Exmantaa]

You are already running a lower MAP thar ours, due to your bigger 2.2 engine volume.

 

But yeah, if your ports are de-restricted, it simply moves on to the next bottleneck; so valves and valve/cam lift & duration. Probably also intake manifold. I would focus more on chargecooling to keep IAT's low and so maintain your power during a summer track day.   

[TFD]

No something utterly stupid: Put on a larger pully to reduce boost = lower power (you want) = less heated air/IAT (you want)...

Something that occurs to the VXT boys as well. Tiny turbo pushed to about 1.5 bar of boost gaining huge torque spikes and shitloads of heat.

 

A bit bigger turbo or SC that is less pushed seems to me like a better solution all together 

[CHILL Gone DUTCH]

No something utterly stupid: Put on a larger pully to reduce boost = lower power (you want) = less heated air/IAT (you want)...

Something that occurs to the VXT boys as well. Tiny turbo pushed to about 1.5 bar of boost gaining huge torque spikes and shitloads of heat.

 

A bit bigger turbo or SC that is less pushed seems to me like a better solution all together 

 

orddred a bigger pulley a few days ago 

[smiley]

 

orddred a bigger pulley a few days ago 

 

 

You run about 1.1 bar atm.

What pully are you thinking about, and what boost are you aiming for?

 

[CHILL Gone DUTCH]

I'm not aiming for a boost level In aiming for a level of performance which I can extract the most out off ( car in general not power ) It a handful at the moment

[Arno]

It's also worth saying o think adding ignition in areas is a waste of time as power is not increased

This is key. Your ignition advance may be knock-limited in various load sites and you can not reach the (theoretical) 'optimum' ignition timing, however there will also be various sites in the map where the 'optimum' is much lower than the maximum advance that's attainable and  'more advance' does NOT translate to 'more power'. Can be quite the opposite acctually. For every load area on an engine there is a sweet spot as far as ignition goes to get the best efficiency if you were to take a theoretical perfect fuel that does not knock. At each side of this sweet spot (either lower or higher) the efficiency tapers off. In some areas (esp. at high load with boost) you will likely run into knock before even getting to the (theorerical) optimum ignition advance, so there you have to make do with that's doable or change physical conditions like charge/boost pressures, (static) compression, temperatures, etc. to get closer to the optimum.

 

Keeping in mind that some changes like lowering static compression lose you power in some areas so overall it may not be the best solution.. But that's simply reality where you need to make some compromises.. In lesser loaded areas where you are not knock-limited it's quite possible to advance to >40 degrees while on a dyno you may well see that the torque perhaps already peaked at around 32 degrees and any added advance is just losing you power. IMHO it's quite doable to road-tune a 'safe' ignition map so it's not knocking all over the place and which will be fine and safe in itself, but to optimise the timing you really need a dyno afterwards and do a 'once over' on all the cells to see if there are (usually part-load) sites that are actually way under- or over-shooting the optimal ignition timing and adjust these to get to the peak output/efficiency again. Won't do much/anything for HP peak load/power 'pub talk' figures as you're often knock-limited as far as ignition goes in the full throttle and high load sites, but it can make an engine/car feel a lot more 'alive' in the part-load areas and a much nicer drive alltogether.

 

This is a step that's often not done on race cars as they tend to spend their life in the upper 25% of the maps, but for a combined road/track car it can be a good investment of some money and time to take a car onto a dyno for some fine-tuning especially for the part-throttle areas. Bye, Arno.

[TFD]

A little addition to Arno:

 

The partial loaded area's cannot be tuned powerwise by OBD-tuner as far as I can tell. The only power you can measure is the full throttle run which will give information only in the high load area.

Tuning the partial load area for more power/better delivery must therefor be done on a dyno (or the old butt-dyno..). OBD-tuner does a knock learning session for the lower area's but this is based on knock rather than power or powerdelivery.

 

One of the bennefits of a turbo with in-car boostcontroller is that I can adjust boost on the fly when tuning.

So first I do a run on 0.5 bar and tune the timing/fuel in that boostarea.

Then a run on 0.6 bar etc. etc.

 

This way I can setup my entire boost area.

 

This should be transferred tot the OBD-tuner thread I think??

[CHILL Gone DUTCH]

Yes it can If you add ignition on partial followed by a fuel learn but tick the knock function you don't get figures but you can maximise the ignition this way

[TFD]

In my understanding it was to prevent knock and not to optimise timing. As Arno said, optimum timing and no knock can be two different things.

[CHILL Gone DUTCH]

But preventing knock is more important If you have as much ignition as possible without knock -1 degree your power will probably still be at peak You could even reduce it by 2 degrees and be at peak

[ultimate]

This might be true for WOT but not in low throttle areas

[ultimate]

In low throttle areas ignition can be too early for maximum power but without knocking

[CHILL Gone DUTCH]

In low throttle areas ignition can be too early for maximum power but without knocking

Then it would have to be done on a RR then but I do stand by my tactic on the road as it's as good as I've been able to get without RR

[Exmantaa]

on a good (brake) RR the whole process is simply much quicker and easier. And probably just as expensive in the end with all the fuel saved.

 

 

Edited by Exmantaa, 31 March 2016 - 08:32 AM.