Drive pressure question
- Thread starter SteveFord
- Start date
also depends on stock turbo steve. while us with the cheetahs might not run all that much more boost i.e. 43lbs on mine our drive pressure at that much boost is much lower. so when i run that much boost i have only about 50 lbs of drive pressure. much more efficiant
Ok. This is why I am asking. After putting on the medium duty up pipe and manifold on the driver side along with my turbo sock I went out and logged a run up to 85 mph to compare my logs from before. What I got now is before at 75mph my vains was at 28.6% and at 80 it was at 30.2% running 32 psi of boost. Now I got at 75 mph 17.3% and at 80 mph 19% also running 32 psi of boost. I logged it twice yesterday to make sure. This is the same tunning as before also. I also ran my truck up to 95 mph and the egts peaked at 1600 when before I stopped looking
. Where I logged this at is the same place I do it everytime so everything pretty much stays the same.
. Where I logged this at is the same place I do it everytime so everything pretty much stays the same.
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Vane position changes like yours are not a direct indication of drive pressure changes. They are encouraging though. Less restrictive manifolds and up-pipes should increase your flow and decrease the pressure measured at the manifold. However, insulating the pipes/turbo retains heat in the exhaust gasses and thus there velocity. So even with the vanes open more, there may be no decrease in the actual drive pressure.
Bottom line, you need to install a gauge.
Bottom line, you need to install a gauge.
Ok thanks Fingers. I'm not to concerned about it since my egts don't go past the 1600-1650 degree mark and the vains are more open than before at the same boost. I posted before I got more boost at crusing speeds and maintain peak boost more than before. If I had something other than a stock turbo I'd get a drive pressure gauge. Thanks for your input guys!
