-
#300
by
theman53
on 21 Sep, 2013 05:27
-
-
#301
by
Jetmugg
on 21 Sep, 2013 08:58
-
All righty then. Thanks for the information and links. I have some homework to do now.
I need to get all my dyno reports as well, since I can't remember the exact HP numbers when running 16 Lbs boost.
My gut tells me that somewhere between 16 and 30 is a sweet spot where I can make good power, not have the turbo "hit" really hard, and hopefully avoid any surging or barking.
Steve.
-
#302
by
libbydiesel
on 21 Sep, 2013 09:02
-
It would not be particularly difficult to create an electronic wastegate controller that would limit boost based on rpm to keep below the surge point.
-
#303
by
Jetmugg
on 21 Sep, 2013 09:53
-
It sounds too tough for me to accomplish before next weekend, however.
I am thinking about running the mechanical boost controller to my switch panel instead of in the engine compartment.
In theory, I could reach over and adjust the maximum boost during a run if necessary.
Any more thoughts on maximum EGT for a flying mile?
I completely agree that 1250F is a safe number to run over the course of a 3 mile run, but I think I may have to push harder than that.
How about 1400F for a mile at something above 110 mph? (roughly 35 seconds)
Steve.
-
#304
by
Jetmugg
on 21 Sep, 2013 10:05
-
The ball, spring, and seat type boost controller looks like it may be a better option than the "pressure regulator" type I currently have.
If I'm understanding the ball, spring, and seat type, it is basically acting like a pop-off valve. It doesn't allow any air to pass until the pressure on the "supply" side is higher than what is required to keep the ball on the seat.
I think I might go ahead and order one from ebay today, with the hopes of having it with my for my departure next Saturday.
I checked the TDI forum - the kind of EGT numbers those guys are throwing around seem WAY too high for what I've read about the IDI engines. I am a rookie at this stuff, but from what I've heard, the limiting factor for our engines is the precups coming loose from excessive EGT's. I just don't have a good feeling for how hot is too hot.
Steve
-
#305
by
theman53
on 21 Sep, 2013 10:23
-
I agree with the EGT thing. I think a constant 1200f is good, peaks of 1600f and back down to 1200f wouldn't scare me as that is what I had on my last engine that lasted 40,000 miles before dropping a precup. Also with the 1.9 head you have a bigger precup which I think is part of the problem in performance 1.6 builds with 1.6 heads. The precups are built for a 52hp engine not a 200hp engine. IMHO anyway. I think the bigger precup the better down to around 16:1 compression. I have little build knowledge but if you look at pulling tractors this is where they strive to be. Less than that they have running issues, more and the egt and boost fights peak performance.
Yes you are exactly right on the ball and spring setup. If you wanted to run 25psi and had it set for that there could be 20psi on the input side and 0psi on the wastegate side. I cannot tell you how accurate it is but usually once it is set I don't mess with it. You can get it close with an air compressor. If they come with 2 springs as mine did use the bigger one. The little one you will never see over 12psi with it.
-
#306
by
RabbitJockey
on 21 Sep, 2013 11:00
-
Also, there are 2 basic types of regulators, bleedin and non bleeding, perhaps only one or the other works as a boost controller.
-
#307
by
Jetmugg
on 21 Sep, 2013 11:02
-
Thanks. I guess those regulators are tune-able by adjusting the preload on the springs, then?
Tell me if this sounds like a reasonable idea....
While I'm on a record attempt, keep the boost on the low side (say 18 psi), until I get past the possibility of surging, then adjust the controller to allow 30 psi once I'm up in the rpm range higher (say above 4000 rpm or so).
Does that seem reasonable?
Steve.
-
#308
by
Jetmugg
on 21 Sep, 2013 11:12
-
Also, there are 2 basic types of regulators, bleedin and non bleeding, perhaps only one or the other works as a boost controller.
Talking to the instructor at the Tech College where I ran the dyno test, he said that it depends mainly on the type of wastegate that is being used. They had a Camaro drag car with a turbo LS1 in their shop at the time I was there. Their wastegate had some kind of air bleed built into it.
The wastegate actuator on this Garrett GT2056 is sealed, no bleeder. It stands to reason, then, that the regulator must provide the path to bleed off excess boost, unless one of the ball and seat type controllers is used.
Steve.
-
#309
by
justiz00
on 21 Sep, 2013 11:25
-
-
#310
by
theman53
on 21 Sep, 2013 12:06
-
I think the surging will go away to a point if you shift further up the rpm. You had all that load and no rpm so in theory if you shifted at 4500rpm and got back on it the engine will be eating up some of that volume of air that was possibly making it surge. By the looks of the map there is nothing you will be able to do to make it completely go away.
Yes the ball and spring *at least mine did* have the spring inside itself. You don't have to touch the waste gate. The rubber hose in the pic below you would cut in two and add it in there. I would add enough hose so you could adjust it in cab as it is sucky to have it under hood as I do. I would set it to your max boost and leave it, if it were me.
-
#311
by
theman53
on 21 Sep, 2013 12:09
-
Steve, what I meant about the wastegate setting was to shorten the actuator length to reduce the preload on the wastegate flapper. Only needed if you see some surge. Hoping your head will flow enough so that it is avoided.
That generic manifold was used on the 173whp Franken dyno 
tubular manifold, bigger turbo and ported head going in for this season. I have a sequential compond setup on the way for this season so I guess we will see how much our Dieselmeken pumps will dyno
Looks like Alcaid already had a method for your surging too.
-
#312
by
745 turbogreasel
on 21 Sep, 2013 14:24
-
Its pretty easy to have 2 stage ball and spring by having a vacuum switching valve either bypass, or switch between 2 of them.
Mine the case halves are fine thread with a locknut to adjust spring preload...the ebay one an external bolt does the same thing
Restrictor and bleed style works too. The mechanical Cummins guys all seem to go that way.
My D24 hits 1450 at full load for the last few years, and I haven't had to look at the pistons in awhile. I do have to back off a bit on long grades, or my coolant heats up. i can run at 1250 all day, and the gauge sits in the middle.
-
#313
by
CRSMP5
on 21 Sep, 2013 14:56
-
thats a fail IMO to not mount the boost controller so you can adj while driving...
now how to set a boost controller.... stop with what you think... and relearn...
you know how to set your regulator on your oxy-acetaline torch? you light it up.. then adjust to the flow you seek?
same thing on the boost regulaor... your looking for the spot you want i tto open at... once you get there.. you have to reduce the boost pressure to close it.. or tun up the regulator for more boost...
if it were mine... id mount it to the shifter.. point it to the side so it works like a throttle on a bike.. that way as you cruize.. you can adjust it and even put stop points on it so you can dial down the boost and increase it as you do your pull and with end points made up you can readjust between shifts.. never having to look at it.. or "reach" for it per say...
i have mine mounted by my knee... out oi the way yes.. but i can grab i with little effort i fneed be..
-
#314
by
libbydiesel
on 21 Sep, 2013 15:04
-
By the looks of the map there is nothing you will be able to do to make it completely go away.
If you made an electronic control with an n75 controller for the wastegate and rpm and boost inputs you could open the wastegate to prevent surge and place that line on the compressor map right up the middle of the efficiency islands.