VE Tables & efficiency ??
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Car: Devastating Droptop
Engine: 355 Supercharged
Transmission: Auto 4L60, Built for 700hp
VE Tables & efficiency ??
I was just wondering where the best rpm to cruise at would be in
Reference to Volumetric efficiency.
For example my car is supercharged and the cam .560int .570exh lift With .230int .235exh duration @ .050 114 LS.
After tuning to 128blm , my VE table shows a dip at 2400 rpm from 30kpa to 90kpa.
2000rpm has higher VE numbers from 30kpa to 90kpa indicating a more Volumetric efficiency.
So is it better to cruise at 2000 rpm or 2400 rpm, 2000 has higher VE numbers.
That equals more air & fuel that equals more power, but 2400rpm has lower #’s
That’s less fuel.
Timing tables are the same for 2000 to 2400 rpm,
Question, should I have a dip there and why is it there,
maybe because thats the point my cam comes alive.
Or Do I need to change the timing?
Reference to Volumetric efficiency.
For example my car is supercharged and the cam .560int .570exh lift With .230int .235exh duration @ .050 114 LS.
After tuning to 128blm , my VE table shows a dip at 2400 rpm from 30kpa to 90kpa.
2000rpm has higher VE numbers from 30kpa to 90kpa indicating a more Volumetric efficiency.
So is it better to cruise at 2000 rpm or 2400 rpm, 2000 has higher VE numbers.
That equals more air & fuel that equals more power, but 2400rpm has lower #’s
That’s less fuel.
Timing tables are the same for 2000 to 2400 rpm,
Question, should I have a dip there and why is it there,
maybe because thats the point my cam comes alive.
Or Do I need to change the timing?
Last edited by LBSZ28BLOWN; 03-27-2004 at 02:22 PM.
#2
With a 230@ .050 cam and a 350 at 2000. You maybe fooling your 02 sensor. Try open loop tuning VE with the tps % at those lower rpms. Less tps means more power at a constant rpm. One of Grumpies methods I picked up. Also, some exhaust systems can cause a dip like that. Usually around 2500 to 3000 though. Has to do with primary length. To minimize the dip that is.
The torque peak is an engines most efficient point IIRC. Not that you want to cruise at 4k. As a guess, I'd say as low as possible and just above where the cam cleans up. That where my carbed cars get their best mileage.
The torque peak is an engines most efficient point IIRC. Not that you want to cruise at 4k. As a guess, I'd say as low as possible and just above where the cam cleans up. That where my carbed cars get their best mileage.
Last edited by Z69; 03-28-2004 at 11:36 PM.
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