EGT's
Post Fiend
Joined: Mar 2007
Posts: 9,010
Likes: 5
From: Johnson City, TN.
c00n I have gotten confused on ths several times and have been set straight. The less resistance the more fuel/power. Trust me. Someone help me explain. I quoted this from the linked website. see below:
A 10k ohm resistor will raise the injection oil pressure approximately 200 psi. Increased injection pressure will deliver more fuel and will deliver more fuel sooner. This increase in fuel deliver and advance will yield higher combustion temperature but your exhaust gas temperature will remain almost steady. Such an efficient burn has it's down side. It will cause an idle rougher than stock. It may also cause the production of nitrous oxides. Thermal efficiency is a function of the high(absolute)temperature divided by low(absolute)temperature. In other words, the higher the peak combustion temperature in comparison to the exhaust temperature the more efficient is your engine.
http://pages.prodigy.net/stevebaz/_i...az/index3.html
A 10k ohm resistor will raise the injection oil pressure approximately 200 psi. Increased injection pressure will deliver more fuel and will deliver more fuel sooner. This increase in fuel deliver and advance will yield higher combustion temperature but your exhaust gas temperature will remain almost steady. Such an efficient burn has it's down side. It will cause an idle rougher than stock. It may also cause the production of nitrous oxides. Thermal efficiency is a function of the high(absolute)temperature divided by low(absolute)temperature. In other words, the higher the peak combustion temperature in comparison to the exhaust temperature the more efficient is your engine.
http://pages.prodigy.net/stevebaz/_i...az/index3.html
Post Fiend
Joined: Apr 2004
Posts: 12,835
Likes: 3
From: Silver Lake Dunes, MI
Less resistance equals more power. I have a 1K resistor in mine but its for helping out with my lope idle that I can't figure out. It doesn't affect my idle either. But anyway back on topic
Casey those temps seem too high to me. With just a 10K mod you might have something else going on. Was the engine luggin when you saw those temps? the engine will create more heat luggin at low rpm then it will high rpm. Usually dropping a gear will help reduce EGT's. How is your air filter and fuel filter? have you checked fuel pressure lately?
Casey those temps seem too high to me. With just a 10K mod you might have something else going on. Was the engine luggin when you saw those temps? the engine will create more heat luggin at low rpm then it will high rpm. Usually dropping a gear will help reduce EGT's. How is your air filter and fuel filter? have you checked fuel pressure lately?
FOREIGN GURU
Joined: Jul 2006
Posts: 7,655
Likes: 7
From: Celaya, Gto. MX
Originally Posted by caseydudem
My gauge is installed pre turbo. Going 70-75 mph I think the rpms were between 1500 and 2000 rpms in overdrive. The egt level was 1200 degrees on hills. That is were it starts to go in to the red danger zone.
TJ, do you have a 1K or a 10K resitor??
Post Fiend
Joined: Apr 2004
Posts: 12,835
Likes: 3
From: Silver Lake Dunes, MI
its a 1k, 1000 ohms. Don't ask why cause I don't know other than it makes my truck not lope like a pulling truck at start up. It has a 10K pot hooked up when I bought it and it would lope in anything higher than 1k so I just put in the 1k resistor like a 10k mod and it works. I think its a quirk of running split shot injectors on single shot programming. So I just got in some AO injectors to DIY into some stage 1's when I get some time and money.
Thread Starter
|
More Turbo
Joined: Mar 2007
Posts: 708
Likes: 0
Correction
My RPM numbers were too low. I was moving at about 70-75 MPH and that puts my rpm at about 2200 give or take some. I dont think it was lugging. It actual seemed to be running really smooth. When it gets up that high she really purs, but that dosn't answer my question. The fuel filter is brand new. The air filter comes due for replacement at the end of the year. I dont have any suggestions but I dont think those are doing anything to hinder flow. I have not checked fuel preasure. I guess I need to get the right tool and do it.
Posting Guru
Joined: Dec 2005
Posts: 1,034
Likes: 0
Originally Posted by caseydudem
My RPM numbers were too low. I was moving at about 70-75 MPH and that puts my rpm at about 2200 give or take some. I dont think it was lugging. It actual seemed to be running really smooth. When it gets up that high she really purs, but that dosn't answer my question. The fuel filter is brand new. The air filter comes due for replacement at the end of the year. I dont have any suggestions but I dont think those are doing anything to hinder flow. I have not checked fuel preasure. I guess I need to get the right tool and do it.
Do you still have the stock down pipe and CAT???
Senior User
Joined: Jan 2004
Posts: 254
Likes: 2
From: Bakersfield, CA
Awhile back I did a test about stock EGT's, before I had an intercooler. I towed the same hill with the same load two weekends in a row, so the second weekend I put the tuner back to stock to see what the EGT's would be. I could still run over 1300* at will once I was about halfway up the hill. This was with only a Tymar intake and a 4" exhaust, no other mods. It surprised me that I still had to back out of it with the stock tune.
I think folks with no gauges run temps like that and don't even know it. I also think we can run higher temps than most are willing do without any damage.
The lower RPM's will have an effect on EGT's, down shift and they'll go right down.
I think folks with no gauges run temps like that and don't even know it. I also think we can run higher temps than most are willing do without any damage.
The lower RPM's will have an effect on EGT's, down shift and they'll go right down.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Posting Guru
Joined: Dec 2005
Posts: 1,034
Likes: 0
Originally Posted by caseydudem
My foot wasn't in it at all. It was on CC. I have a full flow exhaust system. No cat, no restrictions. My dp is 3.5".
Thread Starter
|
More Turbo
Joined: Mar 2007
Posts: 708
Likes: 0
Okay so even if my rpm was at 2200 already I should take it out of over drive for the hills then put it back after. I'm not sure if that would work. My rpm's are going to be pretty far up there. Maybe this will just have to be my excuse to get an IC.
Posting Guru
Joined: Dec 2005
Posts: 1,034
Likes: 0
Originally Posted by nighthawk285
I hate to say this, but you could always slow down once you shift down
1. your cruising at 75mph
2. your pulling up a hill.
3. your pulling a trailer(even though its not meeting your max load rating, still is a larger drag)
Thread Starter
|
More Turbo
Joined: Mar 2007
Posts: 708
Likes: 0
Yeah
You guys are right I probebly shouldn't be towing at that speed, but I was trying to get home for prior engagments. Anyways thats not the question. The question was why my egts are so high when the truck is only stock. I can see this happening easily on a chipped or programed truck, but mine is stock and has full flow capabilities on both ends(intake and exhaust). This is what doesn't make any sense. I normally dont even pull close to that speed. It hurts my fuel millage too much, but I should be able to and I know a lot of guys who do. That is the problem I would like to resolve.
Posting Guru
Joined: Dec 2005
Posts: 1,034
Likes: 0
Originally Posted by caseydudem
You guys are right I probebly shouldn't be towing at that speed, but I was trying to get home for prior engagments. Anyways thats not the question. The question was why my egts are so high when the truck is only stock. I can see this happening easily on a chipped or programed truck, but mine is stock and has full flow capabilities on both ends(intake and exhaust). This is what doesn't make any sense. I normally dont even pull close to that speed. It hurts my fuel millage too much, but I should be able to and I know a lot of guys who do. That is the problem I would like to resolve.