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d.h.
05-19-2008, 21:49
Took fifth wheel out this long weekend.Had new "heath"pcm installed last week.They told me to remove my boost fooler as engine would over boost with it on.
I left on for a bit as I just don,t give that much throttle to apply that much boost
Truck as said easily went to 15lbs with little effort.So I let run for a bit 12-15lbs.I noticed egt,s never rose above 700deg.This trip was 60 miles or so.About half way there I pulled into rest area to remove boost fooler.The boost was to hard to control and I was having to back off all the time.

I noticed right away better control of engine but... everytime I climbed a hill of any length egt,s would rise to 900deg.Same on the way home.Fifth wheel weighs about11000lbs.
My old 23:1 with i/c did far better than this engine is doing. Outside air was only about 55-60 deg so this wasn,t issue.I,m getting nervous abot going over the coke(3000ft) this summer as I don,t think it will do it.
I,m wondering why it was so much cooler with the overboost as apposed to say 10-12lbs? Do I need a differant turbo?
Thanks Dave

ronniejoe
05-20-2008, 04:37
Frankly, in my opinion (which is probably not shared by many), you need a different ECM. I tested Heath's programming on my Suburban and found significantly higher EGT with his programming as compared to what I normally run.

If you want to keep the ECM, leave the boost fooler on. More boost = more air = cooler EGT. You'll be perfectly fine at 15 psi.

Robyn
05-20-2008, 06:40
I agree with RJ

If the sucker likes the extra air and runs good, let it have it.

More air = cooler engine. :D

I have the Heath prom in my 95 and it seems to get plenty of air and runs cool even under a hard pull.

Like daddy used to say, if its working, dont fix it.

Best
Robyn

d.h.
05-20-2008, 09:37
Ron I was concerned about throwing to much boost to new engine.Boost guage only goes up to 15lbs.I ,ll pick up another that goes a little further as guage will pin itself to 15lbs
What level is safe for 18:1.
Thanks for replies Dave

ronniejoe
05-20-2008, 10:20
Actually, I think that running high boost on a new engine is a good thing...it helps to seat the rings quickly.

With the GM-X series of turbos, you won't be able to get any more than about 18 psi maximum and this will only occur below about 2600 rpm. The best I could ever do at 3600 rpm with the GM-4 was about 10 psi. EGT's were climbing and I couldn't stay there very long. To get to these numbers, I ran the waste gate accuator right off of the vacuum pump and took the computer completely out of the loop.

I now run between 20 and 25 psi, depending on conditions, when towing heavy, flat out at 3600+ rpm. I would feel safe with more if I could get there...still working on that. My engine is completely blueprinted with head studs, though. A typical Peninsular 18:1 is likely safe at 20 psi and below.

TAG
05-20-2008, 17:16
Ron, i was wondering if you were getting any closer to having a better turbo setup for sale. I think a more efficient turbo is the last piece of the puzzle on my truck & have been waiting patiently for you to sort one out. If you have one or a time estimate, you could pm me. Thanks.

Jochen Woern
05-21-2008, 21:32
I read some of you guys saying that 15 psi is safe? However, I read before that one should not go higher than 12 psi on a 6.5? Mark Rinker once informed me that at 15 psi, he was using a lot of oil, after backing her down to 10 - 12 psi, the oil usage went back to normal?

I am asking, because I am taking my trailer out for the first time since I have done ALL of my mods (see my signature) this weekend. While towing bone stock last season, the Burb did terrible, 25 mpH was the norm at a steep grade going uphill and the little Bugger got quite hot.

I am now running with Heath's ECM/PCM upgrade as well as the Heath Turbo Master. Empty (not towing anything) at full throttle, I am seeing about 10-11psi of boost, but when kicking this thing in the butt hard off the line, it will hit 1000 degrees EGT. So, what shall I do? Try it out pulling as is, or should I already increase my boost to 15 psi?

Any help is greatly appreciated.

ronniejoe
05-22-2008, 03:18
Ultimately, you must decide what to do for your own rig. What I'm telling you is fact based on my experience. I suspect that Mark's trucks were tired with weak rings. i didn't see a correlation with oil consumption. I ran my stock compression engine at well over 15 psi for a long time. I run my 18:1 at over 20 psi.

With Heath's programming, at 12 psi, your engine will see excessive EGT. As I stated before, that is what I saw with my testing and has been supported by the findings of two of you now in this thread alone. Heath's programming with only 12 psi of boost is a dangerous combination in my opinion.

Turn the boost up or slow down or cook your engine. It is your choice.;)

Now, for those who will want to point out that I broke a piston in my stock compression engine, I will respond that my engine saw multiple extreme excursions beyond 1400F EGT. Many before I had the gages to know what was happening. Driving in a similar fashion after the gages, WOW!:eek: This was with stock programming as well. It had 160,000 miles at time of failure.

rustyk
05-22-2008, 21:02
Well, his engine is 18:1 - I suspect he could safely spool the turbo up to 15 psi - I have a non-wastegated turbo on my AMG/Peninsular (18:1), and according to Peninsular, 15 psi is just fine. EGT is the first clue you're easing into Dangerous Territory, and if the little darlin' likes lotsa air, it should have it.

d.h.
05-23-2008, 17:59
I,m starting to lean towards the more boost is better theory.I installed my boost fooler again.I just have to be carefull:D
I think this ecm is not programmed for 18:1 as no one asked any questions about this.They just wanted to know if I wanted a tow or race program.
That being said I think I should have waited and talked with JK as I think a better program is available.I,m going to install a boost guage that goes to 20psi,hook up my fifth wheel and go play:D. I,m tired of throwing money to the wind.....:D

Robyn
05-23-2008, 19:55
As long as the EGT stays within reason and out of the crispy zone then you are fine.
If you start seeing too much heat just back your boot off the loud pedal a tad.

Too much boost and related intake air temp will translate to EGT and you will know when to back out.
A water alky squirter can do wonders for long grades.
A 5 gallon aluminum tank stuffed into a little corner someplace and used to hold a mix of water and alcohol could help a lot on long grades.

Have fun

Robyn

Jochen Woern
05-26-2008, 20:42
Well, I took the Burb and trailer out this weekend for a Memorial Day Weekend Camp Trip.

I can not explain WHAT a HUGE difference the towing was since I have installed my upgrades:

- Air Intake
- 4" inch exhaust
- Mandrel bend cross over pipe
- Heath Max-E-Tork
- Heath Turbo Master

I ran the boost as per Bill Heath's direction at 14 - 15 psi, and the truck towed better than ever before. EGT's NEVER went above 1100 degrees, even when the boot was giving it all it had. Grades I used to run at 30 - 35 mph, I easily did this time around 55 - 60 mph.

I myself am completely satisfied with the Heath Max-E-Tork programming and adjusting the Turbo Master/Boost with a wrench is a breeze as well.

Based on what I read here on the page, 1250 degrees EGT for a 6.5 should be the max., so hopefully you guys out there can verify that running at 1100 degrees does no harm to the engine.

I would also like to point out that I had no cooling issues at all, the hottest I got was about 220 degrees, but mostly stayed within 195 - 210 degrees. (I did clean my radiator as it was suggested here on the page, flushed all the old goop out of it and cleaned the bottom, removed a lot of dirt and debris. This seemed to help quite a bit as well.

It was fun taking the truck out this weekend with no worries of overheating or being a danger on the freeway due to being to slow.

d.h.
05-26-2008, 22:08
I,m hoping I don,t need to resort to that. I think I just need to dial it in a bit and possibly another pcm may remedy this.I noticed my downpipe rattling against my frame today.Not sure how this started but not much clearance on it .A little heat and a small hammer and that should fix that.
I,ve always backed off on throttle at 900deg as my probe is post turbo and was under assumption that it would read 100-200 hotter down there is this pretty accuate?

Dave

ronniejoe
05-27-2008, 03:38
I,ve always backed off on throttle at 900deg as my probe is post turbo and was under assumption that it would read 100-200 hotter down there is this pretty accuate?

You're guessing with the probe post turbo. The difference in temp will vary based on the amount of work that the turbo is doing. Move the probe to a pre-turbo location for best results.

DennisG01
05-27-2008, 05:19
You're guessing with the probe post turbo. The difference in temp will vary based on the amount of work that the turbo is doing. Move the probe to a pre-turbo location for best results.

Also, you'll notice a MUCH quicker response time in the pre-turbo location. I used to have it post-turbo - after I moved it to pre-turbo, I couldn't believe how much faster the gauge needle moved.

Robyn
05-27-2008, 06:21
I have a question here.

I have two Banks EGT gauges one on the truck and one sitting on the shelf.
Niether one ever goes to the zero peg. Do these gauges ever drop much below the 300F mark

I am begining to think maybe my gauge is hinky???
The pyro in my big truck goes from the pin at 200 to 2000 at the other end.

What do you guys see on your gauges???


Robyn

DennisG01
05-27-2008, 07:22
Mine will drop to zero when the key is off. The lowest I've seen it while running is probably somewhere under 200 (I'm not sure exactly, as that is not the end of the scale I typically worry about :p.

Robyn
05-27-2008, 07:29
The Banks units do not have any power wire (12V) going to them, just the two leads from the probe.
Not counting lighting.

Robyn

DmaxMaverick
05-27-2008, 09:10
If your gage is a microvolt system (no 12V power to it), it is always on. It should never go to zero, unless the location of the probe is actually zero degrees or below. These probes/gages are not all that accurate, from an exact calibration point. They are accurate where the mfg has calibrated them (usually around 800-1000°), and vary accuracy departing from that. These systems are aerospace grade, which is reflected in the price. You can get a range calibrated system, but $100 wouldn't touch the harness assy, which is another issue. If the harness length, material, connections or splicing varies from the calibrated configuration, it varies the range and linear accuracy, as well. For our purposes, only trend tracking is critical, which they do well. They only need to be accurate near the critical temp range, which is usually the case. A microvolt system is inherently less accurate than an amplified system, but are less expensive. Ambient (underhood or underdash) temps can also effect the accuracy of them. Conductor temp also effects conductivity, which is critical on a microvolt system.

d.h.
05-27-2008, 09:10
My guage is an isspro(not sure on spelling).Guage starts at zero as well,with just slight movement at idle.Normaly runs at around 300 deg,without foot in it.The only readon its post turbo is because the downpipe came with it like that.
Robyn I remember the old 425 cat pyro they could get to 900 and beyond with ease.My ISX565 you really don,t need a pyro as the computer will never let it get hot.The new truck we have with an ISX550 doesn,t have a pyro.Those pyro,s were mouted post turbo as well,just a little closer.
I,ve never had a problem before with guage. Iv,e run all my class 8 stuff with the same thought.Once you get to 900 if your not near the top of the hill it,s time to grab a gear.I,ve never had a problem in 23 years of diving the big stuff. I,ts the little stuff:D

Dave

Jochen Woern
05-29-2008, 23:37
Any answers to my below max. EGT question???????

d.h.
05-30-2008, 07:26
I personally would not run at that temp for a very long time.I,ts getting a tad on the hot side in my opinion.

DennisG01
05-30-2008, 08:03
Any answers to my below max. EGT question???????

Pre or Post turbo (your signature doesn't mention it)? If it's post, it's definitely too hot. If it's pre, you're in the range where you'll get varying opinions.

"I did clean my radiator as it was suggested here on the page, flushed all the old goop out of it and cleaned the bottom, removed a lot of dirt and debris"

That right there was more than likely your main problem to start with.

ronniejoe
05-30-2008, 13:17
Based on what I read here on the page, 1250 degrees EGT for a 6.5 should be the max., so hopefully you guys out there can verify that running at 1100 degrees does no harm to the engine.

If your probe is pre-turbo, you will be fine at 1100 F. You are safe to run sustained 1250 F egt with transient excursions above that.