Attention: TDR Forum Junkies I put a drive pressure gauge on my truck. At low boosts I see a minimum of 2-5 psi drive over boost. The ratio scales increasing. At 35 psi of boost I have seen 15-20+ psi. This is for, "more or less", steady state conditions. If I romp on it, I have seen 50+ psi drive at very low boost pressures. This is during the period of time when the turbo is spooling, or the turbo lag.
From what I can tell drive / boost ratio is never 1. 0, but closer to a 1. 2 ratio steady state driving. I would guess the ratio's would be 1. 5 - 2. 0 under easy acceleration and ratio's as high as 10+ under hard acceleration.
Sound about right for a HX35 and my mod's?
Jim
BTW ... .
For those people interested that run exhaust brakes. At idle, with the brake on the drive pressure is about 12 psi. In third gear under hard braking I have seen about 45-50 psi. This is with the truck empty.
I need to work on my set up a bit more, because the with the brake on the exhaust pressure hammers the gauge bad. The pressure spikes are pretty severe. So I am not using the brake too much until I get that resolved and have not used it with the truck loaded at all.
From what I can tell drive / boost ratio is never 1. 0, but closer to a 1. 2 ratio steady state driving. I would guess the ratio's would be 1. 5 - 2. 0 under easy acceleration and ratio's as high as 10+ under hard acceleration.
Sound about right for a HX35 and my mod's?
Jim
BTW ... .
For those people interested that run exhaust brakes. At idle, with the brake on the drive pressure is about 12 psi. In third gear under hard braking I have seen about 45-50 psi. This is with the truck empty.
I need to work on my set up a bit more, because the with the brake on the exhaust pressure hammers the gauge bad. The pressure spikes are pretty severe. So I am not using the brake too much until I get that resolved and have not used it with the truck loaded at all.
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