Need Tips For Setting Wastegate

4x4dually

4x4dually

Moderator
What I "think" I'm seeing on my logger is the drive pressure causing the wastegate to flutter back and forth. I would assume this may be detremental to the turbo or not? I've heard the optimal boost to drive pressure ratio is 1:1, but if I lower the drive pressure by reducing the pressure at which the wastegate opens, at what point will I suffer boost pressure?

Can someone put this into perspective for me so I can understand it?

This is what my latest plot looks like. The drive pressure maxes out at 58.52. At this point, the boost pressure is 43.64, a difference of 14.9 psi.

RPMvsPressures.jpg


I'm pretty sure my WG is set to open at 40 psi from II. It appears that once it pops above 40 and goes to dancing, I lose my top end boost. That plot is of 5th gear and then shifted into 6th gear.

Can someone smart tell me some good info? :D
 
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Dammit. Everyone is busy reading the political section or bashin' vendors or bashin' noobs. :hehe: O well, I'll check back tomorrow. :D
 
Everything I have read suggests keeping waste gate closed as long as possible and using your tuner to control max psi. Looks like your drive pressure is a little high, can you close the waste gate a little more?
 
24vriviera said:
Is it a spring style actuator or diaphragm style?
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Diaphram

duck_04 said:
meh, wastegates are for nitrous. LOL
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So just turnbuckle it closed? I may have to swap that 60 psi sensor out for a 100 psi. LOL

James Stevens said:
Everything I have read suggests keeping waste gate closed as long as possible and using your tuner to control max psi. Looks like your drive pressure is a little high, can you close the waste gate a little more?
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Huh? Leaving it closed longer will make it higher. Also, the higher the drive pressure, the harder it is for the enginer to get rid of heat and exhaust.
 
Just wondering if trying to back the opening pressures down is a waste of time or not. It is nearly impossible to get in there. I'd pretty much have to just pull the SOB and do it on the floor with an air line and a gauge. Not the best design for tunin' on the fly.
 
Those s300's are a pain in the arse to mess with, it would be easier to put an adjustable restriction on the air side, but that's not going to help you lower opening pressure LOL
 
stlcummins said:
Air compressor regulator in the cab for on the fly adjustment. Or am I missing the picture here?
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A regulator could be installed to delay the opening, but I need to speed it up. So...I wonder if I could adjust it all the way mechanically and use the regulator to tweak it...I'll have to think about it. Not too "savvy" on this. LOL
 
Make sure enough tension is left on to hold the flap closed. Otherwise loosen is up some and add some form of boost contoller. T valve, boost elbow, manual/electronic controller.
A particle trap/drive pressure might be a better option seeing that your DP is high.
 
Unhook the boost line and actuator and install an old hand brake lever in the cab with linkage attached to the wastegate arm. When your drive pressure goes up just give an adjustment with the hand brake lever. Post pictures when completed.
 
RonA said:
Unhook the boost line and actuator and install an old hand brake lever in the cab with linkage attached to the wastegate arm. When your drive pressure goes up just give an adjustment with the hand brake lever. Post pictures when completed.
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Of all the "smart" people on this forum that could give intelligent answers.....I get this ^^^^. :hehe:
 
Wouldn't a spring gate take away the spikes? Mostly because you're just adjusting dp instead of boost and dp.

Sent from my DROID X2 using Tapatalk 2
 
I've had real good luck with spring wastegates on twins. Getting ready to do one on a single he351 soon.
 
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