I want to be able to check, and see cylinder pressure in real time. What are guys using to do this?
Question: Internal Cylinder pressure - How to see while running?
- Thread starter monster50iii
- Start date
A 5000psi gauge and some good stainless tubing :roflmao:
Only thing I've been around was from AVL. It's expensive to say the least, if all you want to see is peak pressure you can get away cheaper. But to run a setup that will let you map the pressure waves relative to crank angle it's not worth it just to run on your personal rig. And then if you have software like IndiCom it'll let you hook into the injector lead to see the latency between command and pressure spike, and be able to visualize pilot / post injection effects.
Only thing I've been around was from AVL. It's expensive to say the least, if all you want to see is peak pressure you can get away cheaper. But to run a setup that will let you map the pressure waves relative to crank angle it's not worth it just to run on your personal rig. And then if you have software like IndiCom it'll let you hook into the injector lead to see the latency between command and pressure spike, and be able to visualize pilot / post injection effects.
I dont like to bug Mark more than I have to 
If it is crazy expensive stuff to be able to see cylinder pressure in relation to crank angle I wont worry about it. Thought it'd be really interesting though for fine tuning the timing!!
If it is crazy expensive stuff to be able to see cylinder pressure in relation to crank angle I wont worry about it. Thought it'd be really interesting though for fine tuning the timing!!
The setup I run here cost me $8,500. complete with everything I needed to use it on the engine dyno and chassis dyno(longer cables and stuff). Honestly it is more info than the average person needs and really not worth your time for what you are wanting to do. It won't pay for itself that's for sure! At the end of the day it still takes x-amount of fuel to make a given amount of hp to move a given amount of weight and that won't change unfortunately.
http://www.duramaxdiesels.com/forum/showthread.php?t=10897&highlight=cylinder+pressure
http://www.duramaxdiesels.com/forum/showthread.php?t=17969&highlight=cylinder+pressure
Honestly, one of the coolest things Ive had happen relative to my Dmax hobby was the day Jon and I sat in his truck at Merchant's and he attempted to explain the cyl pressure monitor to me.
http://www.duramaxdiesels.com/forum/showthread.php?t=17969&highlight=cylinder+pressure
Honestly, one of the coolest things Ive had happen relative to my Dmax hobby was the day Jon and I sat in his truck at Merchant's and he attempted to explain the cyl pressure monitor to me.
Right, it can only be so efficient! Btw, if you get a chance check your email, Mark
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Looking at cylinder pressures is like looking at an EKG chart. What is what on the graph takes a bit of learning and one heck of a lot of trial and error. So, unless you are really into tuning, you are wasting your money. But that never stopped me.
As Mark has found, you don't have to have stupid pressures to make power. That in turn keeps the wear and tear on the mechanical parts down. The big thing, IMO is to keep the pressure spikes in check. The smoother, the pressure rise, the better.
I have not make a cylinder pressure setup for anyone in many years now.
As Mark has found, you don't have to have stupid pressures to make power. That in turn keeps the wear and tear on the mechanical parts down. The big thing, IMO is to keep the pressure spikes in check. The smoother, the pressure rise, the better.
I have not make a cylinder pressure setup for anyone in many years now.
Don't think finding out where the peak pressure is at say 35 degrees then moving timing and changing pulse to center that peak on said degree would aid in tuning? I would think that would be easy to help you figure the best tune in a timely matter so you finish with the absolute best tune in 1 day on engine dyno
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You would find that the timing of the peak pressure (PPT) doesn't change a whole lot and is the wrong criteria. PPT is more of a function of how fast the fuel is getting into the cylinder compared to piston velocity. Changing timing WILL affect magnitude of the peak pressure.
Like I said, it is like reading an EKG. The shape of the curve tells you how well you are doing.
Mark has done a lot of good work developing tunes that minimize peak pressure yet make great power. However, his insight has come from endless hours on the dyno, and, well, maybe a little of my experience with my system. I need to stop by and catch up some day.