05-02-2014, 03:02 PM
Ruan,
I know a chap who has constructed his own small programmable PID controller for a VNT. It uses 16x16 maps for everything in 16bit, no checksum support yet though but could have a simple CRC I suppose to check for corruption.
I'll have to get back in touch, but that might be a nice way to deal with things on the 1.9's... or even on a HDi90 with VNT without all the other maps/limiters and possible stuff getting in the way. Just full raw open unlimited control for a VNT turbo.
I'm not sure on the MAF + MAP in the end. I always wondered about having MAF post intercooler. You can get a nice smooth run into the meter, the air temp is accounted for when the inter-cooler output temp varies etc etc. Maybe it'd exacerbate lag a bit more as the compressor flow wouldn't be seen for longer and after the inter-cooler. Hmmmm
As for the bigger sensor, yeah they just strap right in, and with appropriate tweaks work properly over their entire range on a HDi90. Just fit, map appropriately and away you go. There is no reason why you can't run fully MAF controlled fuelling out to 300bhp on one of these.
The big issue is all the other stuff in the ECU that doesn't range well beyond 140bhp, but can be kinda bodged into the 200bhp region 'ok'...
The biggest reason I say 'bodged' is that beyond 140bhp of fuelling you are using the same advance parameters for all injections at that point as you are out to whatever power you run to.
Anyone who has changed these axis without rebuilding ALL the injection maps (including all the 2d adjustment maps that are stacked one after the other), is then just running loads of other stuff incorrectly too.
And when we are coming to 200bhp and 4000rpm, injection timing is crucial unless you want to pop a leg out of bed! You could argue that at this point the old mechanical pump is nicer again hehe!
Steve,
Wow that isn't a good result on the old MAF failure rates. I guess when I saw a lot of these cars they were much younger and newer and probably more likely to be maintained.
Personally I'm surprised people embark on tuning work and buying mods etc, but will skimp on something like the MAF. If you can't get the basic system of a car working right to begin with then what else is gonna be skimped on? A remapped car will never work right when corners are cut. It's those exact reasons why the standard power is so modest, to cover for people who don't maintain the cars properly hehe.
As per cone filters etc, I was never a big fan mainly due to intake air temps. I've got hundreds of logs from 306's with OEM and cone filters and the cone ones ALWAYS soak badly, take ages to cool back off when driving again, and are generally just not so good.
In summer for example the standard air box might read 2degC above ambient when stood still etc, and within about 100m they read ambient air temp.
A cone filter might read 15-20degC higher than ambient and take about 10mins of road driving to get it down near ambient.
If we assume IAT is 20degC in summer, and we move to a cone and get 30deC IAT, then we get (273+20 / 273+30) times less power, or about 97% perhaps. At 150bhp that might be dropping us down to 145bhp potential.
Obviously a *working* MAF will spot that and meter appropriately. So we might still get 150bhp but we might need more turbo speed to get there, so more lag, more heat generated as it's running harder and hotter generally too.
Also we have a ram air effect with the OEM intake, so we might essentially get our intake and MAF restriction 'free' because of the presence of a ram air intake. Take that free ram air away and it's work we then ask the turbo to do instead, so again more heat and less efficiency.
A ram-air enclosed filter is surely the way to go then...?!
I know a chap who has constructed his own small programmable PID controller for a VNT. It uses 16x16 maps for everything in 16bit, no checksum support yet though but could have a simple CRC I suppose to check for corruption.
I'll have to get back in touch, but that might be a nice way to deal with things on the 1.9's... or even on a HDi90 with VNT without all the other maps/limiters and possible stuff getting in the way. Just full raw open unlimited control for a VNT turbo.
I'm not sure on the MAF + MAP in the end. I always wondered about having MAF post intercooler. You can get a nice smooth run into the meter, the air temp is accounted for when the inter-cooler output temp varies etc etc. Maybe it'd exacerbate lag a bit more as the compressor flow wouldn't be seen for longer and after the inter-cooler. Hmmmm
As for the bigger sensor, yeah they just strap right in, and with appropriate tweaks work properly over their entire range on a HDi90. Just fit, map appropriately and away you go. There is no reason why you can't run fully MAF controlled fuelling out to 300bhp on one of these.
The big issue is all the other stuff in the ECU that doesn't range well beyond 140bhp, but can be kinda bodged into the 200bhp region 'ok'...
The biggest reason I say 'bodged' is that beyond 140bhp of fuelling you are using the same advance parameters for all injections at that point as you are out to whatever power you run to.
Anyone who has changed these axis without rebuilding ALL the injection maps (including all the 2d adjustment maps that are stacked one after the other), is then just running loads of other stuff incorrectly too.
And when we are coming to 200bhp and 4000rpm, injection timing is crucial unless you want to pop a leg out of bed! You could argue that at this point the old mechanical pump is nicer again hehe!
Steve,
Wow that isn't a good result on the old MAF failure rates. I guess when I saw a lot of these cars they were much younger and newer and probably more likely to be maintained.
Personally I'm surprised people embark on tuning work and buying mods etc, but will skimp on something like the MAF. If you can't get the basic system of a car working right to begin with then what else is gonna be skimped on? A remapped car will never work right when corners are cut. It's those exact reasons why the standard power is so modest, to cover for people who don't maintain the cars properly hehe.
As per cone filters etc, I was never a big fan mainly due to intake air temps. I've got hundreds of logs from 306's with OEM and cone filters and the cone ones ALWAYS soak badly, take ages to cool back off when driving again, and are generally just not so good.
In summer for example the standard air box might read 2degC above ambient when stood still etc, and within about 100m they read ambient air temp.
A cone filter might read 15-20degC higher than ambient and take about 10mins of road driving to get it down near ambient.
If we assume IAT is 20degC in summer, and we move to a cone and get 30deC IAT, then we get (273+20 / 273+30) times less power, or about 97% perhaps. At 150bhp that might be dropping us down to 145bhp potential.
Obviously a *working* MAF will spot that and meter appropriately. So we might still get 150bhp but we might need more turbo speed to get there, so more lag, more heat generated as it's running harder and hotter generally too.
Also we have a ram air effect with the OEM intake, so we might essentially get our intake and MAF restriction 'free' because of the presence of a ram air intake. Take that free ram air away and it's work we then ask the turbo to do instead, so again more heat and less efficiency.
A ram-air enclosed filter is surely the way to go then...?!
