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cordes
06-26-2008, 09:04 PM
I know that many of our heads were spinning during the tech session trying to keep up with all the incredible information that was presented to us. I thought that perhaps a thread to post a couple of things you took away from the session was in order. I am sure a discussion of the various points will come up, and I think that will be good. Perhaps I misunderstood what was being said etc. Here are my top things I recall.

1. Temprel sells thermocouple probes for cheap. http://www.temprel.com

2. Always weld in the bung as air will most likely get in otherwise and lower EGTs dramatically.

3. Tune for around ~1600*F preferably measured every 500RPM for at least a couple of seconds by dragging the brakes.

4. Weld the bung in the inlet to the turbo about where the Turbonetics logo and .63 are stamped while making sure it is centered in the housing.

5. A company called biwax made the potting compound for the boards. I did a search and it looks as though they were bought out by felpro who is apparently owned by federal mogul. I could not find a page for them.

6. The charge temp sensor is accurate so long as you are using one of the sensors with the exposed wires on it rather than the enclosed ones which apparently came stock. It was suggested by Bucar that a small zip tie was used to keep the wires from fatiguing and breaking off. 5 Digits suggested that a tiny dab of RTV would accomplish the same thing also.

7. modifications to the intake manifold are one of the key elements that will effect EGTs in the different cylinders and it was highly recommended to use as many thermocouples and instruments as possible to determine how evenly the intake is flowing as some cylinders could lean out due to the uneven flow. It was suggested that the exhaust manifold does not play nearly as significant a part in this process and should not be a problem.

8. There really shouldn't be much more than a 50* difference in the exh. gas temp from 1" away from the head in the runner to the inlet of the turbo.

9. ~40* variation in EGTs between cylinders is considered normal even under perfect conditions and anything closer is rare.

10. Getting a baseline for the knock that a given motor generates with a scanner at every 500RPM will help to outline a knock table for the cal. Take that value, add 10% because noise increases with cylinder pressure and anything above that value will be considered knock.

11. A 7* taper from the inlet of the runner in the intake manifold to the opening of the port is considered ideal. Making molds of the runners and taking cross sections of said mold is a good way to make sure the runners are the proper shape and volume.

12. Although premitive by today's standards the knock sensor and tables should not be delted as they are a great safety measure.

13. If a car is tuned for maximum performance on the drag strip it will probably not live at the road course due to the increased time under load. It was stated that when doing the tests on motors the Chryco guys would take the readings at a given RPM after one minute under load.

That is all I can think of right now. Post up what you took away from the session or just a comment.

Clay
06-26-2008, 09:24 PM
I was late to the tech session, then when I headed that way some people came out (about 7:20) and said no one was there, and no one knew what was going on, so they were leaving. I never went back.

Found out later it was on, and GREAT! My only wish is that someone would have video taped the whole thing to post on the web.

cordes
06-26-2008, 09:29 PM
I was late to the tech session, then when I headed that way some people came out (about 7:20) and said no one was there, and no one knew what was going on, so they were leaving. I never went back.

Found out later it was on, and GREAT! My only wish is that someone would have video taped the whole thing to post on the web.

I don't know how many guys I have heard say that they wished they had a video camera. I was told who would be presenting before hand, but I am to new to have known just how great it was going to be since I hadn't heard of the other presenters before.

If by chance there is a tape of it, I would love a copy.

mcsvt
06-26-2008, 09:43 PM
Brian I think you covered most of what I can remember.

The tech session was great! I am at the point where all of the tuning suggestions will help me immensely.

MiniMopar
06-27-2008, 12:51 AM
2. I believe he said the air leak would raise the EGT because it would cause any unburnt fuel to burn in the manifold.

12.5. The best knock sensor setup was the TIII as it had the sensor mounted to the block instead of the intake. Moving the sensor to the block is not a good idea because it is not practical to retune the knock voltage threshold tables. The tables from the TIII cal would not match the dynamics of an 8V setup.

14. The pre-SBEC cals did not have charge temperature compensation for spark advance. It was unclear if the SBEC-I cals had it either.

15. While the pre-SBEC cals did not have 3D tables, the same functionality was achieved by factoring together the results from multiple 2D tables.

16. Finding the right timing and fueling is tricky as knock enters the picture. Keeping the advance ideal can be delayed with more fuel, but eventually it will cause high EGTs due to fuel burning in the exhaust manifold. This can lead to confusion when interpreting the readings and making changes. They seemed pretty convinced that EGTs are one of the more useful pieces of information, even more so than a WB O2.

That's all I can think of....

sdac guy
06-27-2008, 04:35 AM
I was late to the tech session, then when I headed that way some people came out (about 7:20) and said no one was there, and no one knew what was going on, so they were leaving. I never went back.

Found out later it was on, and GREAT! My only wish is that someone would have video taped the whole thing to post on the web. It did get started a half hour or so late. We gathered in the room on time, but I can't really remember why we got off to a late start. Sorry for the confusion surrounding that.

As for video, it would have been nice, but nearly the whole discussion that would have been on the tape was concerning knock sensor dynamics, as that is what the formal session centered on, started by a question from the audience.

What was funny in a way, was that as the knock sensor questions started to die off, Ken asked if there were other questions, nobody raised their hand so he closed the formal session. As soon as the session ended, he was mobbed by 12-15 guys with questions. Duh!

Most of the other details listed here came out in the 1.5 hours Ken, Mark, & Dave spent talking to folks one on one. A video camera would have only shown about 15 guys surrounding Ken, and nothing would have been heard on it.

As a side note, Ken really enjoyed talking to everyone. He called the following morning to thank me for getting him involved in the session. Mark Musial and Dave Zelkowski being there were just added bonuses that were not planned. They just happened by and stopped in. You never know who will show up at an SDAC event!

Craig told me that Dick Winkles was at the Viper plant to speak to those on the tour. That was a complete surprise too!

Barry

ShelGame
06-27-2008, 07:41 AM
Wow, wish I had gone, now.


14. The pre-SBEC cals did not have charge temperature compensation for spark advance. It was unclear if the SBEC-I cals had it either.

FWIW, Russ, none of the cals thru '91 used the Charge Temp sensor for spark compensation. I'm trying to extract the T3 cal from Kelly's '92 SBEC-II he loaned me (been working on it of and on for 8 months). It might have some temp compensation. I've looked at some of the later Mex SBEC-II cals, but they are so different from the earlier stuff it makes my head spin.

spyder
06-27-2008, 08:57 AM
Craig told me that Dick Winkles was at the Viper plant to speak to those on the tour. That was a complete surprise too!



Ran into Dick & Ben from Viper on Woodward Friday night , told them about the show on Sunday . They both showed up @ the museum , driving the ACR & pilot Vipers , seemed to enjoy seeing all the old school Turbo Mopars . Good guys...

MiniMopar
06-27-2008, 10:18 AM
Thought of another one:

1.5. Don't use 1/16" EGT probes as they erode quickly and will break off and go through the turbine. While a 1/8" probe has a slower reaction time, it is still much faster than the thermal mass of everything else the gases come into contact with (ports, manifold, etc).

7.5. While discussing the subject of different EGTs from the 4 cylinders, they seemed a little surprised to hear that some have seen significantly higher EGTs coming from #4. They didn't comment directly, but the discussion that came before seemed to suggest that the problem is more likely to be uneven intake manifold performance than an issue with the head cooling.

dodgeshadowchik
06-27-2008, 12:45 PM
I think you guys summed it up quite well! I sure learned alot.... and the speakers were awesome! I wish I could've stayed for entire thing!

minigts
06-27-2008, 12:54 PM
I thought it was interesting about the knock sensor and what went into proper placement. It REALLY made me think of all the custom intakes out there and where that sensor is. I'm not sure if any of you remember, but he made it very clear that multiple sensors were used in multiple areas of the block to locate the best placement of that sensor. In other words, don't just MOVE it to wherever you feel it would be best suited, the research and work has already been done. And this may have been another conversation I had with someone, but I THINK one of the guys made another point about what the engines are capable of without a ton of changes electronically, but with spark and fuel and monitoring the EGTs.

It was great stuff and just added more questions to the brain about things to do to my car as well as confusion! :)

Russ Jerome
06-28-2008, 10:09 PM
7.5. While discussing the subject of different EGTs from the 4 cylinders, they seemed a little surprised to hear that some have seen significantly higher EGTs coming from #4. They didn't comment directly, but the discussion that came before seemed to suggest that the problem is more likely to be uneven intake manifold performance than an issue with the head cooling.

I've run 4 EGT probes in 3 seperate powerplants, in a few different configurations per powerplant. My experience's were the same as
Gary D had discoverd when we spoke at SDAC/Cinci:

Moving the T-stat does equalize the #4 cylinder EGTs. Maybe the
cooling effects the intake temps as well Im not sure but there is
definately higher EGTs on #4 stock. A simple 1/8" NPT bleed does
well enough they all apear the same on 4 analog gauges.

Im adding a 5th one just prior to the turbo on my new equal length
header, I'd like to prove what they said about temp drops as the
exhaust travels away from head towards the turbo, good stuff.

MiniMopar
06-29-2008, 11:57 AM
Yeah, I agree that there is empirical evidence to support the #4 problem. I'm probably going to do the simple bleed mod on both my cars when the head is off. I was just documenting what I remember hearing.

turbovanmanČ
09-28-2008, 01:16 AM
Bookmarked to read and absorb.

FYI, the TIII knock sensor is on the HEAD, dead center under the intake runners of the head, not the block or intake. ;)

GLHNSLHT2
09-28-2008, 05:46 PM
Masi knock sensor is on the block

CSX321
09-29-2008, 12:04 AM
Masi knock sensor is on the block
2.4L is, as well.

BadAssPerformance
09-29-2008, 12:22 AM
2.4L has a knock sensor? ;)