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Old 02-26-2009, 11:34 PM   #1
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Default Tuning EGTs, very high on low load, butterz in boost.

After wiring up the symtech labs circuit and egt sensor im getting way to high of cruising egts. In boost is another story of good egts.

Things i know:
Advancing timing= lower egts
too lean= high egts

Questions, why in the heck are my egts under 1500* in boost with such low timing, and out of boost driving around town its higher?

MSQ attached, sav will up the datalogg we took.
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File Type: msq Nick 2-26-09.msq (35.2 KB, 138 views)
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Old 02-26-2009, 11:40 PM   #2
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Datalog showing a couple of boosted pulls and a bunch of cruising attached.

Spark map:



Looks really shitty in boost but it just detonates if I add any more advance than that.

Setup is a '95 Protege block, JE pistons, GTX rods, GT2560R on BEGi hotside parts with an MSPNP, 550cc Rx7 injectors, and a Walbro 190.
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File Type: xls map5.xls (662.0 KB, 44 views)
File Type: msq map5.msq (35.2 KB, 111 views)
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Old 02-27-2009, 01:19 AM   #3
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havent had a chance to look at your msq, but what afr's are you running when experiencing 1500 deg EGT?
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Old 02-27-2009, 01:29 AM   #4
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I think you need to do a couple things. FIRST, build set of det cans and tune that spark map. I think your knocksense is lying to you. If the engine truly detonates in boost at any higher number than those, then there's something wrong with the engine. You should be able to advance at least 2-3 degrees from peak torque to peak power no prolemo. That map is just weaksauceville. And it is rather retarded in cruise too. I can run more advance on 87 octane.

EDIT: Should or more less look like this.

Name:  timing1-18-09.jpg
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Old 02-27-2009, 02:24 AM   #5
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Quote:
Originally Posted by patsmx5 View Post
I think you need to do a couple things. FIRST, build set of det cans and tune that spark map. I think your knocksense is lying to you.
No knocksense on this car. On my spark map, which is around 12-13 degrees at 15+psi, the detonation is clearly audible from 3500rpm to redline.

Quote:
Originally Posted by patsmx5 View Post
If the engine truly detonates in boost at any higher number than those, then there's something wrong with the engine.
Timing is correct, timing belt is set correctly. I'm starting to think this is a high-compression motor, honestly.

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Originally Posted by patsmx5 View Post
You should be able to advance at least 2-3 degrees from peak torque to peak power no prolemo. That map is just weaksauceville. And it is rather retarded in cruise too. I can run more advance on 87 octane.
The rest of the map is my timing map, which I haven't changed since Jerry Hoffman tuned my car in June of 07.

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Originally Posted by patsmx5 View Post
EDIT: Should or more less look like this.

My motor would ping on that timing map on CA91.
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Old 02-27-2009, 03:53 AM   #6
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run 40-47 degrees timing in cruise, its the best efficenty range and should lover egts a little.
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Old 02-28-2009, 11:09 PM   #7
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Don't know what to tell you then. That map is terrible and it's the cause of high EGT's at cruise. Why do you drop 10* as soon as you go into boost? If you can run 15* at 5k and 156kPa, then you should be able to run 17-18* at 7k and 156kPa. Several reasons for this. If it knocks when you try, you have other problems. Can't tell you what they are, but I'd try to figure it out quick.

Do a compression test and see what you get. What heatrange plugs and what do they look like after a pull through boost? This thing's aftercooled right? (doesn't say in his sig, just making sure)
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Old 02-28-2009, 11:12 PM   #8
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Quote:
Originally Posted by cardriverx View Post
run 40-47 degrees timing in cruise and it should destroy the engine in short order.
Fixed.
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Old 03-01-2009, 12:38 AM   #9
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What's up with your AFR target table? Are you sure the WBO2 is readying correctly? I agree that something is fucked up.

I really recommend det-cans. You will hear detonation that you can't hear with the naked ear.

If you've put a timing light on it, and checked the cams too...then I think you should put a compression test on it. Good luck. Let me know what happens.

my ultra-safe, conservative spark map for nasty track floggin:
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Old 03-01-2009, 03:01 AM   #10
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Quote:
Originally Posted by patsmx5 View Post
Don't know what to tell you then. That map is terrible and it's the cause of high EGT's at cruise. Why do you drop 10* as soon as you go into boost? If you can run 15* at 5k and 156kPa, then you should be able to run 17-18* at 7k and 156kPa. Several reasons for this. If it knocks when you try, you have other problems. Can't tell you what they are, but I'd try to figure it out quick.
That's beside the point, though. We didn't try to advance timing post-torque peak because I didn't have a Knocksense backing my ears up; all we did was pull timing until we couldn't hear detonation anymore. I want to get that motor CC'd to see what the compresion really is; if it pops out at 10:1 it wouldn't surprise me in the least.

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What heatrange plugs and what do they look like after a pull through boost? This thing's aftercooled right? (doesn't say in his sig, just making sure)
BKR6Es, IIRC, and it's intercooled, yeah.
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Old 03-01-2009, 12:14 PM   #11
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Quote:
Originally Posted by cardriverx
run 40-47 degrees timing in cruise and it should destroy the engine in short order.


Quote:
Originally Posted by patsmx5 View Post
Fixed.
how short, cuz I've been running mid 40s at high rpm light load for evAr.

example from a datalog:
77mph cruise
3450 rpm
40-50kPa MAP
15:1 AFR
immeasurable knock
I'm running 40 degrees...

I think my EGTs are around 1200-1300ish during cruise.
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