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My 383 TBI data logs

ok so I noticed my truck wasn't getting up to temp and when I tore the thermostat apart I found the thermostat stuck open. Truck was running really really good and the BLM's where just about spot on.

So I stuck a 180 thermostat in there and now the thing runs like poop. Knocks more easily now and stutters and dies when I step on the throttle.

I'm posting both tunes up to see if anyone has some suggestions
Tune E is what ran great when the motor was running cool.

Tune F was an attempt to get rid of the knocking but now the truck runs like total poop.

Also posting the data captured with Tune E after the 180 thermostat.

My base timing is set to 6 degrees.
 

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ok so I noticed my truck wasn't getting up to temp and when I tore the thermostat apart I found the thermostat stuck open. Truck was running really really good and the BLM's where just about spot on.

So I stuck a 180 thermostat in there and now the thing runs like poop. Knocks more easily now and stutters and dies when I step on the throttle.

I'm posting both tunes up to see if anyone has some suggestions
Tune E is what ran great when the motor was running cool.

Tune F was an attempt to get rid of the knocking but now the truck runs like total poop.

Also posting the data captured with Tune E after the 180 thermostat.

My base timing is set to 6 degrees.

I did a quick .bin compare between Tune E and Tune F, I did not see any differences in Base Pulse Width, Fuel Tables or Spark Table. I noticed a difference in the initial spark advance, that should retard the timing by about 4 degrees. Basically, with the distributor set to 6 degrees, and the chip programmed to 4 degree the actual advance is 2 degrees.

dave w

Compare.jpg
 
I did a quick .bin compare between Tune E and Tune F, I did not see any differences in Base Pulse Width, Fuel Tables or Spark Table. I noticed a difference in the initial spark advance, that should retard the timing by about 4 degrees. Basically, with the distributor set to 6 degrees, and the chip programmed to 4 degree the actual advance is 2 degrees.

dave w
Ya I think the thinking was that the fuel looked fine but the timing was retarded to try and remove the detonation.

My base timing is set to 6 degrees cause the thing hates to start with anything less.
 
Brian saves the day again!! :thumb: Just wish I would have caught the thermostat problem earlier.

So looks like when it got warm it went lean and made the car run like poop. Kinda crazy what 20 degrees can do. At 160 it ran excellent at 180 things just went down hill.

Enriched the fuel curve and now it runs excellent again. Time to get it on a dyno.
 
Choke is still on at 160. Should not data log for tuning VE table until engine is warmed up...
 
Choke is still on at 160. Should not data log for tuning VE table until engine is warmed up...

I'm assuming when someone is tuning a motor they change those values to the appropriate values. And I assume that's a metaphorical choke that just enrichens the fuel more when cold.

I went back to the 160 thermostat. 180 it ran good but felt like it was being held back. 160 just has such a drastic difference in how the thing runs. If I end up rebuilding the thing sooner so be it. I run synthetic in the thing anway so should hold up to running cooler better.

This seems to be a huge debate on the internet. A lot of people swear by the 160 and have logged thousands of miles and then when they tore down found minimal wear. You also see people swear by 180 and above with some chart and specs that state wear at different temperatures. But then don't really state what oil was used and from what year the oil was produced for those charts. Oil has come a long way since the old days. I couldn't find anything conclusive. Since this truck isn't a daily driver just a toy and I use it to tow my boat I'm going to go with what works the best in my motor.
 
ASS U ME is not good... had the tuner known then yes it can be done. Daily driver and the standard 180 T stat is really a better option, not so on built engines which are usually for power and racing. But then a race engine would get an oil change with filter dismantled and filter elements checked for metal debree each race day. It's not a wear issue with lower T stat temps.

Really no debate you can make more horsepower with 160 T stat, also no debate on better fuel economy and lower emissions with 180 T stat. Also no debate on engine wear with either using same oil. It can be debated, but facts are clear.

Daily driver gets oil and filter changed, with no inspection at 3,000 miles ish?

The 20 degree difference brings oil temps up over 212 degrees which boils out moisture in oil from engine heating and cooling causing condensation and engine being vented with outside air through PCV system bringing in moisture. No condensation/moisture issues on race engine with oil changed daily and no PCV system...

Oils have come a long way. But for flat tappet cams there is no oil on shelf at parts store with properties sufficient for flat tappet cam motors. Let alone one with aftermarket cam and increased spring rates so valves don't float at high RPM.

Since all new cars are roller lifters this is something us guys with old flat tappet motors should know or cam wear is accelerating to point of failure... good synthetic helps but still does not have additives old oil had for flat tappet cam motors.

For instance the last flat tappet cam engine made was in 2006 and way behind the curve, I believe the last one before it was 5 years earlier. It was the 4.0L engine in jeeps, last year. It had a special oil made by Chrysler who by them owned Jeep. Warranty void if you did not use their oil... it was a synthetic blend with added phosphorous and zinc.

This is why I use Amsoil 10w/40 synthetic clearly marked on bottle Added Phosphorus and Zinc. It covers my 1990 Suburban flat tappet, 1972 IH flat tappet, more than needed in my 1994 LT1 roller cam. It also covers my lawn mower! So I only keep one oil around for everything. These additives to oil have been severely reduced in all shelf oil. This was phased out of oil due to emissions regulations.

Only other Dino oil I know of sufficient for flat tappet cams is Comp Cams Break in oil, Brad Penn racing oil which are both made from Pennsylvania crude and labled for Off Road Use Only! Close to best oil out of ground in the world. Brad Penn racing oil is the old Kendall oil that is always found in VW air cooled shops for dune buggys. Was also oil of choice for Harleys. Harley Davidson brand oil back then was Kendall oil...
 
The 20 degree difference brings oil temps up over 212 degrees which boils out moisture in oil from engine heating and cooling causing condensation and engine being vented with outside air through PCV system bringing in moisture. No condensation/moisture issues on race engine with oil changed daily and no PCV system...
I agree that seems to be the general consensus and it seems to be a very heated debate on a lot of forums. But try and find some RECENT data with modern oils to back up those claims. I've tried and wasn't able to find anything just a lot of what people thought. Which isn't completely bad but what used to be doesn't always hold true as time goes by. I found a couple charts with data without a source of who created the chart and what oil was used or when it was created. It's kinda like using wikipedia as a source to turn in a homework assignment. :) Just not going to fly.

Oils have come a long way. But for flat tappet cams there is no oil on shelf at parts store with properties sufficient for flat tappet cam motors. Let alone one with aftermarket cam and increased spring rates so valves don't float at high RPM.
I don't have a flat tappet cam I have a roller cam and full roller rockers. Lunati 60120 is a roller cam.
 
Question: I found a section that says Coolant temp Spark Correction.

Now what this does seems to be self explanatory. Now the question I have is we have Main Spark Advance table. Seems to me you would set up that table to the best possible conditions for whatever temperature you intended to run. So for me 160 then you could possible remove the advance by sticking in a hotter thermostat say the 180 and look to see how much it detonates then remove the appropriate amount of spark to reduce detonation. Then you could stick in a 195 and remove more.

Now to me that seems to be a fairly simple way to look at it. But I assume many other things change as the temperature of the motor changes.

Anyone try this and get any results they care to share?
 
Question: I found a section that says Coolant temp Spark Correction.

Now what this does seems to be self explanatory. Now the question I have is we have Main Spark Advance table. Seems to me you would set up that table to the best possible conditions for whatever temperature you intended to run. So for me 160 then you could possible remove the advance by sticking in a hotter thermostat say the 180 and look to see how much it detonates then remove the appropriate amount of spark to reduce detonation. Then you could stick in a 195 and remove more.

Now to me that seems to be a fairly simple way to look at it. But I assume many other things change as the temperature of the motor changes.

Anyone try this and get any results they care to share?

It's my understanding that the Coolant Temp Spark Correction does exactly what it describes; adds or subtracts timing from the main spark table based on engine temperature and engine load (Kpa).

Basically, I have not needed to modify the Coolant Temp Spark Correction Table. Typically the chips I do, the engine has a 180 degree thermostat. I think your logic is solid, with a 160 thermostat the Coolant Temp Spark Correction Table could gain some benefits from some minor modifications. I would think several cold start data logs would be required to construct a baseline to figure out what modifications are a benefit!:waytogo:

dave w
 
Question: I found a section that says Coolant temp Spark Correction.

Now what this does seems to be self explanatory. Now the question I have is we have Main Spark Advance table. Seems to me you would set up that table to the best possible conditions for whatever temperature you intended to run. So for me 160 then you could possible remove the advance by sticking in a hotter thermostat say the 180 and look to see how much it detonates then remove the appropriate amount of spark to reduce detonation. Then you could stick in a 195 and remove more.

Now to me that seems to be a fairly simple way to look at it. But I assume many other things change as the temperature of the motor changes.

Anyone try this and get any results they care to share?
Yeah that would work, just depends what the tables says it will do at what temp.

Like Dave said, I don't touch them. They work fine on all motors. You make your timing adjustments to engine in Main Spark table and let all the other qualifiers do there thing.

But if you change engine running temp on a good tune then you need to retune for that temp. Temps of engine change everything.
 
It's my understanding that the Coolant Temp Spark Correction does exactly what it describes; adds or subtracts timing from the main spark table based on engine temperature and engine load (Kpa).

Basically, I have not needed to modify the Coolant Temp Spark Correction Table. Typically the chips I do, the engine has a 180 degree thermostat. I think your logic is solid, with a 160 thermostat the Coolant Temp Spark Correction Table could gain some benefits from some minor modifications. I would think several cold start data logs would be required to construct a baseline to figure out what modifications are a benefit!:waytogo:

dave w
What I'm thinking is a really hot 100 degree day and towing the boat up a steep long hill. I know that stock radiator won't keep up. On the stock motor temps would climb past 195 on the same conditions. I'm thinking this would be a good way to create a safety net.
 
What I'm thinking is a really hot 100 degree day and towing the boat up a steep long hill. I know that stock radiator won't keep up. On the stock motor temps would climb past 195 on the same conditions. I'm thinking this would be a good way to create a safety net.

I have a screen shot of the .bin you posted earlier in this tread. Basically, the table is set to ZERO for the towing temperatures you expect to experience. From my towing experience, I think adding auxiliary electric cooling fans to come on at 210 F is a better safety net. Adding or subtracting timing in a towing situation does not seem like a good plan in my humble opinion.

dave w

Coolant Temp Table.jpg
 
I have a screen shot of the .bin you posted earlier in this tread. Basically, the table is set to ZERO for the towing temperatures you expect to experience. From my towing experience, I think adding auxiliary electric cooling fans to come on at 210 F is a better safety net. Adding or subtracting timing in a towing situation does not seem like a good plan in my humble opinion.

dave w
Ya I haven't made any changes. Just wanted to understand the tables first. I'm just thinking if I were in an over heat condition it's better to run like crap then detonate.
 
What I'm thinking is a really hot 100 degree day and towing the boat up a steep long hill. I know that stock radiator won't keep up. On the stock motor temps would climb past 195 on the same conditions. I'm thinking this would be a good way to create a safety net.
Get a radiator that is sufficient for needs. Or do like factory does in a towing package and add an oil cooler. This also removes heat from engine putting less strain on cooling system.

195 is not near a hot or close to overheating engine. It is barely close to what newer engines run.

Couple of things to note. Water boils at 212 degrees and causes a cooling system to overheat because the water turns to steam.

Add antifreeze which is also an anti boil and boiling point rises. Add a 15 pound pressure cap to cooling system with a 50/50 mix of antifreeze and boiling point is now 265 degrees f. So your cooling system is still cooling if you hit 265f. Which I would never let an engine get that hot but running 220 up a long hill towing won't hurt a thing. Certain parts of the cooling system like near head may be up to 265f inside but won't turn to steam.

Water turning to steam is what causes overheat of cooling system like when it's bubbling and puking out fluid into your overflow tank. Cooling system will stop cooling/taking heat from engine when boiling occurs because steam does not flow.

Taking away spark when an engine is warm (195) not close to hot yet... won't help it run cooler. If you want the engine to start to run cooler change AFR lower... at 220 degrees....
 
Ya I haven't made any changes. Just wanted to understand the tables first. I'm just thinking if I were in an over heat condition it's better to run like crap then detonate.

Adjusting the Spark Compensation Table is more like a research project. Unfortunately, the $42 data log does not show spark advance.:eek1: The data log would not show what the SA was, given a specific RPM / Kpa!:eek1: I can't think of an option that would fix the no SA data in the data log! It would be impossible to know how much SA to adjust without knowing the SA was in the first place.:doah: Personally, I would not risk engine damage on a SWAG (Scientific Wild A$$ Guess) when it comes to timing.:waytogo:

dave w
 
Unfortunately, the $42 data log does not show spark advance.:eek1: The data log would not show what the SA was, given a specific RPM / Kpa!:eek1: I can't think of an option that would fix the no SA data in the data log!
dave w
We are working on that right now! Won't work with stock chip, must modify ALDL output in bin first, but then you would have timing in ALDL. But as a tuner you could simply burn a chip or emulate with simple change then data log with spark advance numbers!
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?547-42-adding-spark-advance-to-Data-Stream
 
Adjusting the Spark Compensation Table is more like a research project. Unfortunately, the $42 data log does not show spark advance.:eek1: The data log would not show what the SA was, given a specific RPM / Kpa!:eek1: I can't think of an option that would fix the no SA data in the data log! It would be impossible to know how much SA to adjust without knowing the SA was in the first place.:doah: Personally, I would not risk engine damage on a SWAG (Scientific Wild A$$ Guess) when it comes to timing.:waytogo:

dave w

SA? Sounds like work that term means System Agent to me :haha:
*edit* I see you shortening Spark Advance

The idea I was thinking of wouldn't actually be a guess. Since I operate at 160 normally sticking a 180 thermostat in and driving it around would show how much the motor detonates at those temperatures. I should be able to dial back the timing at those temps and get the detonation to stop. Since there isn't a significant number of adjustments it would seem easy enough just to dial back small amount until it goes away.
 
Adjusting the Spark Compensation Table is more like a research project. Unfortunately, the $42 data log does not show spark advance.:eek1: The data log would not show what the SA was, given a specific RPM / Kpa!:eek1: I can't think of an option that would fix the no SA data in the data log! It would be impossible to know how much SA to adjust without knowing the SA was in the first place.:doah: Personally, I would not risk engine damage on a SWAG (Scientific Wild A$$ Guess) when it comes to timing.:waytogo:

dave w
Actually you can with my xdf and adx file set up with data tracing. I do it! Although it is not in the data log output 9yet were are working on that too).

While data logging or after a data log has been recorded you just click the Data Trace button, then open Main Spark table and a bubble roams around the cells exactly where the spark advance is.
 
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