'Performance' engine maps
Discussion
Hi Guys,
With my increasing understanding and tinkering with the mapping on my car, i'm becoming curious as to what exactly is different about the canned performance tunes kicking around (Wortec etc.).
If the car is still running the MAF then unless the intake path has changed the MAF transfer function shouldn't need adjusting, which only really leaves the PE commanded fuelling and Spark maps.
Are these tunes optimising the timing, or merely bringing the fuelling back to better levels through the PE table? Unless the injector fuelling tables are being mucked around with....
Excuse any ignorance i'm sure i've still plenty o gaps in my understanding but trying to see where the key gains are from a canned tune.
Meanwhile i'll keep chasing my stoichometric tail with my MAFless tune
With my increasing understanding and tinkering with the mapping on my car, i'm becoming curious as to what exactly is different about the canned performance tunes kicking around (Wortec etc.).
If the car is still running the MAF then unless the intake path has changed the MAF transfer function shouldn't need adjusting, which only really leaves the PE commanded fuelling and Spark maps.
Are these tunes optimising the timing, or merely bringing the fuelling back to better levels through the PE table? Unless the injector fuelling tables are being mucked around with....
Excuse any ignorance i'm sure i've still plenty o gaps in my understanding but trying to see where the key gains are from a canned tune.
Meanwhile i'll keep chasing my stoichometric tail with my MAFless tune
MadMaxHSV said:
Hi Guys,
With my increasing understanding and tinkering with the mapping on my car, i'm becoming curious as to what exactly is different about the canned performance tunes kicking around (Wortec etc.).
If the car is still running the MAF then unless the intake path has changed the MAF transfer function shouldn't need adjusting, which only really leaves the PE commanded fuelling and Spark maps.
Are these tunes optimising the timing, or merely bringing the fuelling back to better levels through the PE table? Unless the injector fuelling tables are being mucked around with....
Excuse any ignorance i'm sure i've still plenty o gaps in my understanding but trying to see where the key gains are from a canned tune.
Meanwhile i'll keep chasing my stoichometric tail with my MAFless tune
air, fuel spark With my increasing understanding and tinkering with the mapping on my car, i'm becoming curious as to what exactly is different about the canned performance tunes kicking around (Wortec etc.).
If the car is still running the MAF then unless the intake path has changed the MAF transfer function shouldn't need adjusting, which only really leaves the PE commanded fuelling and Spark maps.
Are these tunes optimising the timing, or merely bringing the fuelling back to better levels through the PE table? Unless the injector fuelling tables are being mucked around with....
Excuse any ignorance i'm sure i've still plenty o gaps in my understanding but trying to see where the key gains are from a canned tune.
Meanwhile i'll keep chasing my stoichometric tail with my MAFless tune
The only real changes you can make with the tune for power is spark and fuel.
Idle is another story and needs air, which you can control with IAC or ETC.
So therefore a lot of power is gained from ending up at a more optimal AFR. Id shoot for 13:1 or maybe 13.2:1 at WOT you can experiment with a little richer at peak torque, not because richer makes more power, but because richer will allow more spark, which might get your timing closer to MBT (max torque).
For instance. Untuned ar SRR I did a 453rwhp, this was with AFR around 11:1 with almost no changes but fueling at 13:1 this went to 496rwhp. I think saw a little knock at WOT, so pulled a degree or two out and run a 502rwhp. I was running under 20* at WOT
So my next task is high octane fuel and a ported throttle. Id like to think Ill end up with 520rwhp. But we will see.
There are some tunes around if you are interested. I think I have a "predator" handheld tuner "performance tune". Basically its rubbish. Ive seen most peoples tunes around here and its pretty much the same approach. Spark and fuel
Get your MAFless tune sorted so that commanded afr tracks actual afr to within a couple of points. Then check with the maf enabled you are still in the same zone, if not adjust maf.
THEN go and pay Charile or someone with a dyno some money to do your experimentation with spark timing. I think an hour or two will tell you a lot. The dyno operator usually will give you some hints or tips for more power too. You can compare 12.8:1 to 13:1 as well and see what works best etc.
Also make sure you get no intake vacuum under WOT (ie Barrometric = MAP). That will tell you if your engine is restricted and needs something sorting out in the intake dept. (like mine)
I'll keep going with the VE tuning. Getting a little frustrating where most of the map tracks stoichy AFR to 1.00 or 0.99 BEN one day, take it out the next and its bouncing around high 15's AFR!!! Put this down to IAT but doesn't always correlate on my logs, but surely it should be getting richer with higher IAT's...
The drag day sorted out part of the WOT areas of the map, just need to work on ironing out some of the glitches I still have at part throttle.
While on topic, logs of my AFR when lifting off from WOT goes off the chart. No knock or anything nasty at the same time, but is this a normal symptom of the wideband/headers or something to be concerned about . By VE entries at the low pressure end of the chart are still much higher than the stock map, and the DFCO is disabled as per AutoVE intructions.
The drag day sorted out part of the WOT areas of the map, just need to work on ironing out some of the glitches I still have at part throttle.
While on topic, logs of my AFR when lifting off from WOT goes off the chart. No knock or anything nasty at the same time, but is this a normal symptom of the wideband/headers or something to be concerned about . By VE entries at the low pressure end of the chart are still much higher than the stock map, and the DFCO is disabled as per AutoVE intructions.
MadMaxHSV said:
Put this down to IAT but doesn't always correlate on my logs, but surely it should be getting richer with higher IAT's...
The drag day sorted out part of the WOT areas of the map, just need to work on ironing out some of the glitches I still have at part throttle.
While on topic, logs of my AFR when lifting off from WOT goes off the chart. No knock or anything nasty at the same time, but is this a normal symptom of the wideband/headers or something to be concerned about . By VE entries at the low pressure end of the chart are still much higher than the stock map, and the DFCO is disabled as per AutoVE intructions.
Make a map of IAT vs BEN use that in either an injector modifier table etc. My E38 has an injector flow vs IAT table, where I do that. In theory intake charge blend factors deal with it, but they are multi dimensional and harder to get right. But whatever works best for you.The drag day sorted out part of the WOT areas of the map, just need to work on ironing out some of the glitches I still have at part throttle.
While on topic, logs of my AFR when lifting off from WOT goes off the chart. No knock or anything nasty at the same time, but is this a normal symptom of the wideband/headers or something to be concerned about . By VE entries at the low pressure end of the chart are still much higher than the stock map, and the DFCO is disabled as per AutoVE intructions.
That should help sort out any weird stuff with higher intake temps etc. The inverse relationship you mention is probably down to the charge blend action.
You need to sometimes use common sense in some areas of the map. Low pressure should be low values, that will drop your fuel. It can also be how the injectors work. My idle area is a bit off because the injectors are 72lb so cant meter small amounts. I just got it close and went back to closed loop. Email me your tune Ill have a look at the table shape.
What puzzles me with these is what is sacrificed? Presumably emissions. Why don't the manufactures get them more right from the start? Monkfish do a remap for £500 which they told me adds 38BHP to the 354ps LS1. Lots of pestering failed to yield a before and after dyno print though so I haven't had it done.
I do notice my car falters - a sort of partial miss fire - occasionally and wonder if this would be corrected with a richer at full load tune. Or is it the anti knock stuff at work.
I do notice my car falters - a sort of partial miss fire - occasionally and wonder if this would be corrected with a richer at full load tune. Or is it the anti knock stuff at work.
You would need to look at some logs mate.
FWIW the VYII 285kw HSV LS1 is only a tune away from the 225KW LS1 tune from 1999
Main changes are fuel and spark.
You can download the tunes from www.holdencrazy.com and compare them if you like. Its quite interesting.
The software is free from efilive.com
FWIW the VYII 285kw HSV LS1 is only a tune away from the 225KW LS1 tune from 1999
Main changes are fuel and spark.
You can download the tunes from www.holdencrazy.com and compare them if you like. Its quite interesting.
The software is free from efilive.com
and if you really get into it ringram can do you a good deal on the full product. he's not allowed really to plug the fact he's the UK distributer because he doesnt pay to advertise on here but he's one of the good guys normally and one of the most helpful people I've come across when it comes to supporting the product he sells. Be prepared for lots of reading though if you choose to map yourself.
Wortec usually dont do rolling road tunes hence why they wouldnt supply a graph. They normally map a car using realtime mapping on the road which they claim is the better technique. Seems reasonable argument as most of us drive our cars on the road as opposed to on a dyno. But there have been a number of people recently who have since had a dyno tune and would appear to have seen gains both in the graphs they've been given and in how they feel the car drives. If you've read the threads you'll know the discussions that ensue from them so I wont try convince you either way.
Mark at Rapid will do you a dyno tune if you choose to go that way and will provide before and after graphs. It was what I had done years ago and it transformed the car.
Roger at Monkfish will get you a Wortec road tune and from many people on here reporting back you can be sure that you will not be disappointed at the gains you will see whether it makes some number or other or not on a bit of paper. Bonnie I think may have had it done recently as part of her package of mods - ask her how she feels it changed her car.
Basically a tune from either will transform your car - chose one and go get it done, you wont regret it.
Wortec usually dont do rolling road tunes hence why they wouldnt supply a graph. They normally map a car using realtime mapping on the road which they claim is the better technique. Seems reasonable argument as most of us drive our cars on the road as opposed to on a dyno. But there have been a number of people recently who have since had a dyno tune and would appear to have seen gains both in the graphs they've been given and in how they feel the car drives. If you've read the threads you'll know the discussions that ensue from them so I wont try convince you either way.
Mark at Rapid will do you a dyno tune if you choose to go that way and will provide before and after graphs. It was what I had done years ago and it transformed the car.
Roger at Monkfish will get you a Wortec road tune and from many people on here reporting back you can be sure that you will not be disappointed at the gains you will see whether it makes some number or other or not on a bit of paper. Bonnie I think may have had it done recently as part of her package of mods - ask her how she feels it changed her car.
Basically a tune from either will transform your car - chose one and go get it done, you wont regret it.
Its impossible to tune timing on the road and get any empirical data. You need a dyno for that.
Also changes in power output from AFR will also need a dyno.
Road tuning is only ok for getting an accurate afr, but knowing what it is wont tell you if it is for best power.
As per the recent contraversial thread regarding AFR ratio's
95% of my time is spent on road tuning. But you need to do the last bit on a dyno otherwise you will not be optimised IMO.
Also changes in power output from AFR will also need a dyno.
Road tuning is only ok for getting an accurate afr, but knowing what it is wont tell you if it is for best power.
As per the recent contraversial thread regarding AFR ratio's
95% of my time is spent on road tuning. But you need to do the last bit on a dyno otherwise you will not be optimised IMO.
granada203028 said:
What puzzles me with these is what is sacrificed? Presumably emissions. Why don't the manufactures get them more right from the start? Monkfish do a remap for £500 which they told me adds 38BHP to the 354ps LS1. Lots of pestering failed to yield a before and after dyno print though so I haven't had it done.
I do notice my car falters - a sort of partial miss fire - occasionally and wonder if this would be corrected with a richer at full load tune. Or is it the anti knock stuff at work.
Cars are tuned for emissions primarily yes. Not fuel efficiency, nor power. Also for saftey. That means rich AFR. Timing interestingly enough isnt so bad stock in general anyway. Early Monaro's were a bit off but the later stuff is pretty good. Id say main gains on the vxr8 etc are from fueling. Monaro its a combination.I do notice my car falters - a sort of partial miss fire - occasionally and wonder if this would be corrected with a richer at full load tune. Or is it the anti knock stuff at work.
As for faltering, it could actually be too rich. Or as you say something like Burst knock retard, or even torque management etc. Lots of options. Burst knock retard can be a bad boy. Its designed to pull timing not when knock is detected, but when airflow delta exceeds a certain value. So any high performance engine will experience it even without knock. Its preventative. Needless to say it will need tweaking to stop it messing things about.
All good stuff. I'm sure tweaking on the road must be useful but a rolling road is always going to be more definitive.
The guy I spoke to at wortec said the remap made the most difference in the low to middle speed ranges. I can perhaps understand this as at low speed the valve overlap/scavenging effects make the engine the most dirty so making emissions is more difficult and more torque has to be sacrificed.
I see the remap is now £690. I'm afraid for that no graphs simply isn't on. I remember seeing rapid GP offering a dyno on your car remap for £250 - a bit more like it.
I'm on a 10% pay cut this year and have seen colleagues made redundant. The credit crunch is very real. I can't understand how companies can put up there prices so much?
The guy I spoke to at wortec said the remap made the most difference in the low to middle speed ranges. I can perhaps understand this as at low speed the valve overlap/scavenging effects make the engine the most dirty so making emissions is more difficult and more torque has to be sacrificed.
I see the remap is now £690. I'm afraid for that no graphs simply isn't on. I remember seeing rapid GP offering a dyno on your car remap for £250 - a bit more like it.
I'm on a 10% pay cut this year and have seen colleagues made redundant. The credit crunch is very real. I can't understand how companies can put up there prices so much?
I agree, most gains in how the car feels are felt in the low pressure midrange area where you spend most of your time.
In this area closed loop ensures that AFR doesnt mean much. There is little overlap in the stock cam for emissions reasons.
So its all down to spark timing. Thats where realtime spark changes on the dyno are invaluable. I think most of the wortec development has been done on the dyno and therefore with a package the same baseline can be used and checked on the road.
Thats not so bad. If you do some diy or beskpoke mods of course that baseline is less relevant.
As with anything, if you can get a drive in someones car, that helps. Dyno days and track days dont tell you anything about how the car drives 95% of the time at part throttle. In that area, timing is everything.
In this area closed loop ensures that AFR doesnt mean much. There is little overlap in the stock cam for emissions reasons.
So its all down to spark timing. Thats where realtime spark changes on the dyno are invaluable. I think most of the wortec development has been done on the dyno and therefore with a package the same baseline can be used and checked on the road.
Thats not so bad. If you do some diy or beskpoke mods of course that baseline is less relevant.
As with anything, if you can get a drive in someones car, that helps. Dyno days and track days dont tell you anything about how the car drives 95% of the time at part throttle. In that area, timing is everything.
Edited by ringram on Thursday 9th July 09:34
One thing to bear in mind and I'm not saying any of the reputable tuners often mentioned here do this but an "easy" way to market a tune as performance is to simply map the drive by wire throttle a little more aggressive. I have seen this snake oil on other marques.
Hell, it's all the "sport" button does on 99% of most cars.
Hell, it's all the "sport" button does on 99% of most cars.
ads_green said:
One thing to bear in mind and I'm not saying any of the reputable tuners often mentioned here do this but an "easy" way to market a tune as performance is to simply map the drive by wire throttle a little more aggressive. I have seen this snake oil on other marques.
Hell, it's all the "sport" button does on 99% of most cars.
Hell, it's all the "sport" button does on 99% of most cars.
This is what worries me, hence I must see graphs and numbers. I'm not going to rely on my senses. I want the throttle to remain nice and progressive. I hate cars with light long travel accelerators where the first bit does everything. My 3 litre Granada was like that. It had a twin choke synchronous carb with a direct linkage. Butterfly valves are highly non linear. The later 2.8 was much better with smaller butterflies (but bigger chokes) and a variable radius pulley for the cable.
Trying another cars is not going to help much. Remember I have a stock VZ CV8 with the M12 ratio set. Unique in the UK as far as I know. So it will be difficult to separate the effect of that compared to a remap.
granada203028 said:
ads_green said:
One thing to bear in mind and I'm not saying any of the reputable tuners often mentioned here do this but an "easy" way to market a tune as performance is to simply map the drive by wire throttle a little more aggressive. I have seen this snake oil on other marques.
Hell, it's all the "sport" button does on 99% of most cars.
Hell, it's all the "sport" button does on 99% of most cars.
This is what worries me, hence I must see graphs and numbers. I'm not going to rely on my senses. I want the throttle to remain nice and progressive. I hate cars with light long travel accelerators where the first bit does everything. My 3 litre Granada was like that. It had a twin choke synchronous carb with a direct linkage. Butterfly valves are highly non linear. The later 2.8 was much better with smaller butterflies (but bigger chokes) and a variable radius pulley for the cable.
Trying another cars is not going to help much. Remember I have a stock VZ CV8 with the M12 ratio set. Unique in the UK as far as I know. So it will be difficult to separate the effect of that compared to a remap.
Spose you don`t have your old M6 going spare do you?
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