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Hybrid K04 Turbo Discussion
- Thread starter J@mes
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- discussion hybrid k04 turbo
It seems to be a characteristic of this hybrid. Its not like its requesting the spike so i can't see how mapping will eliminate it, unless the map requests a very low value to compensate.
I wonder if the DV could be utilised to vent off unwanted boost with an additional suitably rated map sensor, creating similar conditions to that of gear changes when excess boost is measured.
They do its called custom settings and I use it.
load scale factor %
Its not a question of upping the boost tho, if only that simple! lol
I've been scratching my head wondering why everyone keeps the existing MAP sensor when the maximum value it reads is below the boost levels people can run.
Is there nothing available?
Apparently you can use the MAP sensor from a PD150! Which can read higher! Well i say higher but it actually reads less! It out by around 0.5BAR so at 1 BAR in VAG-COM its actually at 1.5BAR! So would probably have to be mapped to suit or turn the load right down and log then slowly increase it!
Will need the ECU to adapt to first though!
Will need the ECU to adapt to first though!
I'm using a PD map sensor. Reads to just over 2 bar absolute. I believe APR use it on their stage 3+ motorsport stuff.
Unlikely that anyone will release or write code for the general public requesting more than about 1.5 bar, so generaly a different map sensor isn't necessary. When the engine goes bang because said owner hasn't kept an eye on boost, egt's etc how much will they bitch and cause damage to whichever tuning house they have used.
I'm sure if bills engine goes pop, he'll accept that it's because he's way past what is sensible on standard fuels. It only takes a sensor, a fuel pump, a fuel injector or an actuator to take a dump on you and it's bye bye engine at these boost levels.
Tuning should be able to iron out boost control issues. The speed at which the ECU chases requested boost can be adjusted across the rev range, so boost spikes can be ironed out. 18g spools quickly, and with the code for my IHI, boost control was awfull. Overboost city.
3rd gear boost log from mine. The turbo is flat out (well 95% duty cycle from 6000rpm on.
Unlikely that anyone will release or write code for the general public requesting more than about 1.5 bar, so generaly a different map sensor isn't necessary. When the engine goes bang because said owner hasn't kept an eye on boost, egt's etc how much will they bitch and cause damage to whichever tuning house they have used.
I'm sure if bills engine goes pop, he'll accept that it's because he's way past what is sensible on standard fuels. It only takes a sensor, a fuel pump, a fuel injector or an actuator to take a dump on you and it's bye bye engine at these boost levels.
Tuning should be able to iron out boost control issues. The speed at which the ECU chases requested boost can be adjusted across the rev range, so boost spikes can be ironed out. 18g spools quickly, and with the code for my IHI, boost control was awfull. Overboost city.
3rd gear boost log from mine. The turbo is flat out (well 95% duty cycle from 6000rpm on.
drops to 1.5bar max'd boost from just over 6500rpm.
Is your scaling on the graph manual or are you getting the 3000mbar out of logged scaling.
How does your 18g compare to the VF34 previous?
Is your scaling on the graph manual or are you getting the 3000mbar out of logged scaling.
How does your 18g compare to the VF34 previous?
The scaling on the graph is a calc. But It ties up with the boost guage, and at tickover I'm seing 820mbar vs 1000mbar on same day. Makes max reading about 3100 on new map. Boost guage on higher boost just about pegs the 30psi guage and nearly pegs the map sensor, so it all ties up.
It drops to 1.7 bar at 6500 and 1.5 bar at 7000. Holds better in higher gears. Will hold 1.7bar at 7000 in 4th.. In 3rd, the wastegate just can't close fast enough to spin the turbo up.
I've updated the graph above with IHI lines (done in 4th)
I was getting 245g/s peak from the IHI and I'm seeing a little over 300g/s with the 18G. There is a bit more in the turbo, as when we let it go to 100% duty cycle, we saw 10-15g/s more of air. It's now limited to 95% in the upper rev range. You know my history with IHI's bill.
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Does it not run lean John as the ECU is seeing less boost? I'm guessing it will adjust the fuelling accordingly from the airflow.
But I'm thinking if i fit the pd sensor the ECU will get confused as I'm running the larger MAF housing to compensate for the 4Bar FPR.
So if the ECU is seeing less than actual boost as well as less than actual airflow, the fuelling is going to be difficult to control no?
But I'm thinking if i fit the pd sensor the ECU will get confused as I'm running the larger MAF housing to compensate for the 4Bar FPR.
So if the ECU is seeing less than actual boost as well as less than actual airflow, the fuelling is going to be difficult to control no?
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mine was tuned on an s4 maf and a pd map.
I woulld expect it to run too much timing if you just changed the map with no other adjustments.
The only way your car will run lean is if you max out the injectors, or your 02 probe is knackered. The ECU will adjust fueling many times a second based on the 02 readings in the exhaust. Maf and map just give a heads up, and adjust ignition timing.
If you're running more than 14psi then the fueling will be 0.8-0.83 lambda. The diesel map would effectively under read by 18% so at 21psi it would think you were at 17. Fueling would still be 0.83, but you'd have more advance.
I woulld expect it to run too much timing if you just changed the map with no other adjustments.
The only way your car will run lean is if you max out the injectors, or your 02 probe is knackered. The ECU will adjust fueling many times a second based on the 02 readings in the exhaust. Maf and map just give a heads up, and adjust ignition timing.
If you're running more than 14psi then the fueling will be 0.8-0.83 lambda. The diesel map would effectively under read by 18% so at 21psi it would think you were at 17. Fueling would still be 0.83, but you'd have more advance.
that sounds very promising..
when you next going to jump on a dyno and get some figures?
Would logging the duty cycle of these hybrid turbos determine whether there is more left in them and its just the loading thats needs adjusting to up the power output.
Could you make manual adjustments to the timing (SPS or V Tune etc) to compensate. Would this keep the knock sensors and CF's happy. As long as your running a stand alone boost gauge you'll always know what true boost is anyway.
Does anyone know what a pd150 map sensor costs.
I dont understand the need for a new map sensor really unless your mapper wants to request more than 1.54bar. It doesn't matter though because he can still request 1.54 bar, but it doesn't limit the turbo in anyway, the turbo will still boost beyond that if it is capable of doing so. Its just vagcom wont be able to measure it. Your boost gauge can though
I dont think its needed in our case Carl. On BT's yes as the mapper might want 1.7-1.8bar requested but its highly unlikely a tuner is going to map our turbos further than requested 1.54bar. There's no need as they only spike above 1.54bar, they cant hold above that, well not for long. Mine can hold 1.54+ only for about 500-750rpm max.
I dont think its needed in our case Carl. On BT's yes as the mapper might want 1.7-1.8bar requested but its highly unlikely a tuner is going to map our turbos further than requested 1.54bar. There's no need as they only spike above 1.54bar, they cant hold above that, well not for long. Mine can hold 1.54+ only for about 500-750rpm max.
vag-com wont read it as me7 wont read it either - saturated sensor 5v MAP signal for the 1.55+pressure
its the table relationships and dependancies which relate around MAP and fueling, ign and a host of other tables. change the effective scaling same as bigger MAF tubes, injector sizes, and its then balancing the respective tables to keep it all running happily (but in complete ignorence of real world figures or those logged and reported by vag-com and the likes)
its the table relationships and dependancies which relate around MAP and fueling, ign and a host of other tables. change the effective scaling same as bigger MAF tubes, injector sizes, and its then balancing the respective tables to keep it all running happily (but in complete ignorence of real world figures or those logged and reported by vag-com and the likes)
PD map sensor is about 60 quid, but you guys don't need it, and don't need bigger maf tubes etc.
I wouldn't want to run with a saturated map sensor (for more than just a spike) unless I had something other than the ECU controlling boost.
On the hybrid, tuning should be able to control the boost spike to something reasonable, and should be able to max the turbo out at higher rpm.
On a small port 1.2bar at the limiter is about 225g/s. The head won't flow much more at 1.5bar and will only get up to 245g/s ish. From what I have read, the turbo just isn't capable of shifting that much air. VF34 wont shift more than that either.
It looks like it wil give you a solid 20hp over the standard one. I don't know how much you people expect.
You're all stuck in the same boat as billy and I. You fit a turbo and then 2 days later think 'I should have gone bigger'. I've only done that 4 times.
I wouldn't want to run with a saturated map sensor (for more than just a spike) unless I had something other than the ECU controlling boost.
On the hybrid, tuning should be able to control the boost spike to something reasonable, and should be able to max the turbo out at higher rpm.
On a small port 1.2bar at the limiter is about 225g/s. The head won't flow much more at 1.5bar and will only get up to 245g/s ish. From what I have read, the turbo just isn't capable of shifting that much air. VF34 wont shift more than that either.
It looks like it wil give you a solid 20hp over the standard one. I don't know how much you people expect.
You're all stuck in the same boat as billy and I. You fit a turbo and then 2 days later think 'I should have gone bigger'. I've only done that 4 times.
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