New Bolt in turbo... FP White Rabbit.
Originally Posted by MalibuJack
This is a bit offtopic so I'm reluctant to make a very technical post.. But I wanted to point out that two turbos at the same pressure, can indeed have different MAF readings, given one is more efficient than the other at that pressure, then the air density would be higher, and that should result in the slightly higher reading.
I suspect at 19-21psi, the stock turbo is at the tail-end of its efficiency window, and the white rabbit is just getting into its window, so given that overlap, its likely the numbers would be the same in that range. Where the WR would shine is beyond that point where it can still provide a decent cooler/denser air charge at higher boost levels, and maintain that level of pressure through a higher RPM, so at readline at higher boost, you'd probably see MAF readings over 2000hz where you might see a max of 1990hz or so on a stock turbo (I've seen over 2000hz but not by much)
I'm by no means a thermodynamics or fluid dynamics expert, so I can't argue too much about what or why this works the way it does, but there are some obvious differences between the two compressor wheels which would indicate to me its efficiencies are at different points.
I suspect at 19-21psi, the stock turbo is at the tail-end of its efficiency window, and the white rabbit is just getting into its window, so given that overlap, its likely the numbers would be the same in that range. Where the WR would shine is beyond that point where it can still provide a decent cooler/denser air charge at higher boost levels, and maintain that level of pressure through a higher RPM, so at readline at higher boost, you'd probably see MAF readings over 2000hz where you might see a max of 1990hz or so on a stock turbo (I've seen over 2000hz but not by much)
I'm by no means a thermodynamics or fluid dynamics expert, so I can't argue too much about what or why this works the way it does, but there are some obvious differences between the two compressor wheels which would indicate to me its efficiencies are at different points.
I saw in the mid 1900hz in my 03 with the stock turbo and the 9.8 hotside?
Originally Posted by evo 8 ya
I saw in the mid 1900hz in my 03 with the stock turbo and the 9.8 hotside?
Originally Posted by evo 8 ya
I saw in the mid 1900hz in my 03 with the stock turbo and the 9.8 hotside?
Differences in compressor efficiency will change the amount of air mass moved at a given pressure, but the difference is slight. Especially since most poeple are talking about running these two turbos in the meat of thier efficiency range. Its like comparing a 20g to a 56 trim at 25 psi on my 2g. 48 lbs/min in both cases. At 30 psi the 20g would be dropping boost since its over its max flow range (50 lbs/min), while the 56 trim would be moving a solid 55 lbs/min. Max the two turbos out and the better one will start to pull away 
Another thing to consider is intercooling. Any difference in compressor efficiency will be further cut down by intercooler efficiency. To use the extreme example for the sake of illustration, with 100% intercooler efficiency, compressor efficiency would be irrelavant, as far as charge temps/density go
MAF frequencies are also more likely to vary with temperature changes, while actual mass flow rates can remain similar. A given Hz number does not equal a given airflow. Temp and Baro have to be accounted for as well. I have yet to measure these things in the EVO however. This is from my DSM experience... But the airflow meters are very similar, and the same principles apply. The fact that airflow readings can change when changing the intake is correct. This mostly applies at low airflow levels though, like idle. I just installed an open filter. When I have the means to do so, I'll swap back to the stock airbox and log the change just for fun.
Another thing to consider is intercooling. Any difference in compressor efficiency will be further cut down by intercooler efficiency. To use the extreme example for the sake of illustration, with 100% intercooler efficiency, compressor efficiency would be irrelavant, as far as charge temps/density go
MAF frequencies are also more likely to vary with temperature changes, while actual mass flow rates can remain similar. A given Hz number does not equal a given airflow. Temp and Baro have to be accounted for as well. I have yet to measure these things in the EVO however. This is from my DSM experience... But the airflow meters are very similar, and the same principles apply. The fact that airflow readings can change when changing the intake is correct. This mostly applies at low airflow levels though, like idle. I just installed an open filter. When I have the means to do so, I'll swap back to the stock airbox and log the change just for fun.
Good explanation, thats actually what I was eluding to..
My car is a bad example for efficiency, I've spent the past year getting the most efficiency out of everything I can.. For me it might be hard to do a true apples-to-apples comparison that would closely apply to other cars.
My car is a bad example for efficiency, I've spent the past year getting the most efficiency out of everything I can.. For me it might be hard to do a true apples-to-apples comparison that would closely apply to other cars.
Originally Posted by pyrovice
So how much more efficient is the WR? In laymans terms please.
Originally Posted by EVO8LTW
What intake/filter and what boost level? I understand that the intake can make a big difference. Out of curiousity I reinstalled my stock MAF pipe last night (still with the Buschur filter) and while the car ran much richer in the low and mid range, above 5000 rpm or so the MAF readings were about the same as with the Buschur MAF pipe. Still under 1800. Maybe my boost gauge is reading way low?
I remember I was really happy because I had to run race gas and like 22-23psi with my old eclipse with a 20g strapped to it to get anything in the 1900hz range.
Correct me if I'm wrong but isn't there suppose to be a couple WR equipped EVOs going on the dyno this weekend? Im dying to see some numbers with cams/reflashes - especially before my WR goes on...!
Originally Posted by spoolingEVOx
How is the BB conversion in terms of reliability compared to the standard WR or OEM TD05?
Just out of curiosity, can the WR produce power up to 8000/8500?
Just out of curiosity, can the WR produce power up to 8000/8500?
