Lower EGT'S

[jlwelding]

Here's what I have, ambient temps have drop pretty good around here. From 108 to 94 today, a pretty good drop, enough to lower egt's? Probably not. I adjusted valves Sunday from 10 - 20 to 8 - 18. Here's the kicker, my egt's have droped overall 150*. My weight is 11k so I am used to seeing high egt's as a norm. I am driving a usuall route when I notice my gauge is lower than normal, I think its stuck so I give it the gas it goes up and I think this is strange. I am thinking this is big news, so I call Mike, he's like yea yea man I like your new found temps but I got to go, can I call you later Kicked to the curb! Just kidding Mike no biggie. I noticed the turbo spools faster no doubt, but you think it would make that much diff? I am cruising at 60 flat road and egt's 575 that has never been before, it should have been at least 675.

[ISX]

Here's what I have, ambient temps have drop pretty good around here. From 108 to 94 today, a pretty good drop, enough to lower egt's? Probably not. I adjusted valves Sunday from 10 - 20 to 8 - 18. Here's the kicker, my egt's have droped overall 150*. My weight is 11k so I am used to seeing high egt's as a norm. I am driving a usuall route when I notice my gauge is lower than normal, I think its stuck so I give it the gas it goes up and I think this is strange. I am thinking this is big news, so I call Mike, he's like yea yea man I like your new found temps but I got to go, can I call you later Kicked to the curb! Just kidding Mike no biggie. I noticed the turbo spools faster no doubt, but you think it would make that much diff? I am cruising at 60 flat road and egt's 575 that has never been before, it should have been at least 675.

Why do you think I run 6/15... Its incredible. Still not sure what it does to mileage. I beat the crap out of it, blowing smoke every chance I got, tonsss of city driving and drove more like 65-70 on the highway and still got 24mpg.

[Mopar1973Man]

Here's what I have, ambient temps have drop pretty good around here. From 108 to 94 today, a pretty good drop, enough to lower egt's? Probably not. I adjusted valves Sunday from 10 - 20 to 8 - 18. Here's the kicker, my egt's have drooped overall 150*. My weight is 11k so I am used to seeing high egt's as a norm. I am driving a usual route when I notice my gauge is lower than normal, I think its stuck so I give it the gas it goes up and I think this is strange. I am thinking this is big news, so I call Mike, he's like yea yea man I like your new found temps but I got to go, can I call you later Kicked to the curb! Just kidding Mike no biggie. I noticed the turbo spools faster no doubt, but you think it would make that much diff? I am cruising at 60 flat road and egt's 575 that has never been before, it should have been at least 675.

Well sorry about that but I saw you name on the caller ID I figured I'd let you talk to me a for a little bit before I left the house... I'm also running 8/18 setting too and saw about a 3 MPG gain hauling 16,000# GCW weight. I can't speak for the EGT's because of my stock injectors it was much higher that typical that the RV275 hence why I got busy fixing the RV's again... So I'm getting itchy to haul the TT again and see what it will do...

[jlwelding]

That was with stock inj., my ddp 50's need to go back to the shop. I was on the same road again today and I cant belive that just the valve adj did that. I dont know why I didnt notice it before, I have done this on the old eng.- well never mind I just answered my own thought. Anyway, I may try 7 n 17 some time.

[AH64ID]

You didn't pull the DDP 50's out at the same time did you?Opening the exhaust valve sooner should give you higher EGT's, as it would have a similar effect on EGT's as retarding the timing, less time for the exhaust in the cylinder. With the ramp rate of our valves based on the tappet size I am really surprised that there is any change at all. The stock cam opens the valve at a very steep rate and a few thousandths on the valves may only relate to a degree or so on the amount of open time, hardly enough to get more of a charge into the cylinder. When all the variables are kept constant but boost, a general rule of thumb is 10° for each 1 lb of boost.. very general! But 150° is a large difference.

[ISX]

When I was testing with valve lashes between the min and max tolerances one thing can definitely say is that tighter lash does not in any way increase the EGT. I can see why it would possibly, but it just doesn't happen.

[jlwelding]

You didn't pull the DDP 50's out at the same time did you?No I pulled the ddp's afew months ago. Opening the exhaust valve sooner should give you higher EGT's, as it would have a similar effect on EGT's as retarding the timing, less time for the exhaust in the cylinder. With the ramp rate of our valves based on the tappet size I am really surprised that there is any change at all. The stock cam opens the valve at a very steep rate and a few thousandths on the valves may only relate to a degree or so on the amount of open time, hardly enough to get more of a charge into the cylinder. When all the variables are kept constant but boost, a general rule of thumb is 10° for each 1 lb of boost.. very general! But 150° is a large difference.

I dont have a clue as to what is going on here. I am headed to the fuel pump in the morning, I will keep yall informed.

[jlwelding]

Ok I am back, it took longer to run through that tank than I thought. 16.23 mpg and I have done nothing. This motor came from a donor truck, it has 210k on it and been in my truck for 9k miles. I ran it stock for a long time just so I could go thru the motions again. I cleaned the injectors and serviced the fuel system along with setting the valves at 10 - 20. Ran this way for several months and fuel mileage stayed around 14.50 and 14.75 like clock work. I reinstalled edge ez about a 6-8 weeks ago, one fuel mileage was 14.75 and I thought that suc's. Ran another and 15.0 ok better. I know what the motor before ran and this one ran the same temp. About 6-7 days ago I posted here wow where did this come from, a big decrease in egt's. No change in driving, no change in weight, I weigh 11k. So where did this come from? I read a post that read something like it took a while before they saw increase in fuel mileage after running 2 stroke.All I did is change valve adjustment from 10-20 to 8-18. I will be the first to say that alone does not sound like it alone would do that much. Ok here we go again, same road same mph everything the same (100 degree day) and egt's are hotter. I will check mpg after this tank. Something is weird, egt's usually run 650 to 800 shifting gears and level off at 625 on flat road. When egt's went lower I was shifting and temps were 600-625 and level of at 575. I know everybody is going to say ambient temp cant make that much change and I will agree. But thats all that was diff. I will stay on this and see where this goes. Mean while could timing in vp make this kinda change?