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Knock problem with ECMlink data! Please HELP!

Dark_Horse

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Joined
Sep 6, 2010
Messages
303
Location
Morrison, CO
IMHO, you should drop your fuel pressure down to 37psi and drop your injector global to -53%. Then tune the global till your gram/rev is hovering around 25-26 and your combined FT at idle is +/- 2% or so. That will give you a better starting point.

Also, for pump gas, 11.8:1 is pretty lean.
 
Last edited:

throughfaith323

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Sep 24, 2008
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530
Location
Forked River, NJ
Thanks so much for the input guys! I'm learning a lot through this process. This knock will be a huge benefit in the long run.

So here is what I've done. I lowered the fuel pressure to 37psi using the ECMlink diagnostic mode. I then set my global to -53 and deadtime to 330. Started the car up and fuel pressure was at roughly 39psi. Left it at that for now (getting eatin alive by mosquitos and was running out of time /ubbthreads/images/graemlins/banghead.gif) until I really learn how to tune....when I do, I will then start from scratch. I then played with global and deadtime a little, since FP was not exactly 37, and got the idle A/F's and part throttle pretty decent Averaging 14.9ish over a period of time.

From here I tweaked MAFcomp a little to bring down my A/F ratio to low 11's. I know I am missing some steps in my tuning process, but I am in the learning process and have huge overload from all the reading I've been doing. I have questions about tuning with ECMlink and will get to that in my next post. After adjusting MAFcomp to enrichin the A/F ratio, this is what I ended up with:



From this log you can see that the knock dropped to almost zero counts across the board!! The 3 logs right before this one (as I was adjusting the MAFcomp) showed similar signs of knock to the knock I was getting before these fuel adjustment (richer), but was improving after each adjustment towards low 11 A/F ratios.

ALSO I MUST NOTE: All of these logs were done with 92octane gas from WAWA(cheap gas). I will be filling up with Sunoco 93 octane fuel only from this point on and now that I'm actually learning to tune and do things right.

Tuning/coolant questions to come......
 

throughfaith323

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Sep 24, 2008
Messages
530
Location
Forked River, NJ
Now for the engine cooling questions.....

Engine Cooling (thermostat):

I've read a TON of threads on people going back and forth about running a colder thermostat. My question is, what do you guys recommend? Keep in mind I do have ECMlink, so I WILL be able to force my car into closed loop IF coolant temperatures are below 180degF (stock thermostat temp).

My driving conditions: I do not daily drive my car nor do I often get stuck in traffic when I am driving my car. I live in New Jersey and do not drive in the coldest times of the year (when the roads have been salted). When I am driving my car I usually "get on it" a lot (not every chance I get, but enough).

Some of the pros and cons I've either thought about or read about when using a lower temp thermostat (correct me on anything I may be wrong about):

Some PROS could be:
-Safety margin with headgasket concerns
-Lower chance for detonation/knock to occur
-Lower under-hood temperatures
-Lower intake temp in some cases due to lower under-hood temperatures (haven't gotten to optimal intake pipe routing yet /ubbthreads/images/graemlins/banghead.gif)

Some CONS could be:
-Mainly lower engine efficiency
-Decreasing fuel atomization (20 degrees shouldn't affect it too much right?)
-Winter coolant temps being too low when cruising (could be adjusted with some airflow blockage to the radiator like trucks/buses do)
-Others, but I am drawing a blank right now.


This all being said, what temperature thermostat do you guys suggest I use? If you are very knowledgeable and have experience with this question, please chime in! Please point out any CONS that I may have left out and would be of some concern.
 

beaner

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Jun 22, 2005
Messages
1,562
Location
b'ham, mi
Just keep it between 190 and 205. I think it comes down to how good the radiator is. I have a civic half radiator in mine and experimented with a few thermostats to keep it where I wanted. It hovers in the low 200s but it for sure doesn't have a 200+ thermostat in it.
 

MuffinMan7580

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Aug 6, 2011
Messages
142
Location
Fort Bragg, NC
Quoting throughfaith323:
I lowered the fuel pressure to 37psi using the ECMlink diagnostic mode. I then set my global to -53 and deadtime to 330. Started the car up and fuel pressure was at roughly 39psi.




Fuel pressure should be set at 0 vacuum/Boost (@ atmospheric pressure). Set it with engine off, only running the fuel pump, or you can start your car, disconnect the vacuum line on your AFPR, set fuel pressure, then re-attach.

Coldest thermostat I would run would be 180*. If you run anything much colder than that, oil temperature could possibly not come up to operating temperature. If you're worried about underhood temps, you can raise the rear of the hood a bit (washers underneath the hinge), and if there's weatherstripping there, you can take that out (I haven't looked on mine, although I know 1g DSM's have it).
 
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throughfaith323

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Joined
Sep 24, 2008
Messages
530
Location
Forked River, NJ
Quote:
Fuel pressure should be set at 0 vacuum/Boost (@ atmospheric pressure). Set it with engine off, only running the fuel pump.



That is what I did. I turned the pump on using ECMlink and set the pressure to 37. I then set global/deadtime and then turned the car on. I checked the base fuel pressure by taking off the vacuum line to the FPR. the FP gauge was then reading 39 /ubbthreads/images/graemlins/dunno.gif. I will change it sometime soon before I get into too much tuning. I have a lot to learn first.

Quote:
Coldest thermostat I would run would be 180*. If you run anything much colder than that, oil temperature could possibly not come up to operating temperature.



This is why I am unsure what to do. I have read about many people suggesting running a thermostat 10* (170*) or even 20* (160*) cooler. The other suggest what you have suggested here....stick to stock and run the 180*. I do not know what to believe because both stock t-stat and cooler t-stat have have their advantages and disadvantages.
 

Dark_Horse

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Joined
Sep 6, 2010
Messages
303
Location
Morrison, CO
There's no reason to run a colder thermostat unless you're having problems with your car running hot. And even then, there are other things you should do before jumping into a colder thermostat. Did you do a radiator flush? Is your rad cap holding pressure? What coolant mix are you running? Did you bleed the system properly? Does your rad core have a bunch of fins that are all bent up? Is your AC condenser still in the vehicle?

Plenty of stuff that can be addressed before running a really cold thermostat.
 

thecman02

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Joined
Nov 3, 2007
Messages
918
Location
Kalamazoo,MI
I'd recommend sticking with stock thermostat. When your car is running too hot and the thermostat is for sure opening the problem is a lack of heat exchange between the radiator. Make sure the radiator is clear of debris, make sure the coolant is flushed out well. Also make sure it is a 50/50 mix and that it isn't straight coolant. Check to make sure the radiator cap is holding correct pressure.

As far as tuning you should really be at 11:1. You need to post logs too, that is 1000x more useful then a screen shot. We can go into the log and see all the settings you have your car set to.
 
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