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engine theory/easy simple mods

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3 different grades of Diesel?????

cummins ism overhaul

to start off much of my focus will be on the 12v since that is the truck i own, however all dodge cummins, and diesels in general would be great, i am always interested in theories used in heavy duty applications. thats why i am putting this in the general diesel forum.



anyways, due to the economic times a conflict of interests have come up. many if not all of us have all felt the pressure of our slow economy, for myself, it has increased my drive in the search for peak efficency, but as many of us are aware of, if we modify our trucks for better fuel mileage while increasing or at least not sacraficing power, it often is not very cost effective. example new injectors and or f. a. s. s. both do improve fuel mileage (in most cases) but it is a long time before we recover our costs. in good times this was not a problem, but for many of us we cannot swing those costs anymore. so i would like to talk about any and all ideas/theories, that people have, and obviously personal experience weighs more than just theoretical.



so lets get started, my current project/idea is wrapping the exhaust. i have been focused on preturbo since i think that post turbo would have at best no change, and at worst a negitive effect.



i have already wrapped the exhaust manifold, and today installed the turbo heat blanket. i ordered heat products 1"x50' 2000* insulating tape and the turbo blanket. my results at the moment are strictly the exhaust tape around the manifold. all the results are very early, only 200 miles or less, so what i am seeing, cruising: egt's have stayed the same, it is hard to say exactly sometimes it seems higher, sometimes, believe it or not it seems lower. prior to install boost was below 4 (bottom of my gauge), now boost is hovering right at the bottom, in other words it seems to have picked up some boost (1 or 2 psi) for all the other conditions being the same. acceleration (mild/moderate, daily driving): boost comes up a little faster, not much but some. egts stay low, this however might be attributed more to the intake work i have recently done (will discuss later). i do feel more power based on seat of the pants meter. the truck also seems happier cruising then before. lastly its looking like i am gaining some fuel mileage but i cant be sure yet. just the exhaust wrap alone, but the turbo wrap too, really lowered the amount of heat that soaks into factory air box, a rule of thumb i was told by a reputable source states for every 1 dergee of intake temp change equals 3 degrees of exhaust temp change, this i think was manifold temps not ambient air temps. the intake is probably 30 degrees cooler, im sure this is having a big effect on the egt temps. under hood temps are also drastically reduced, and im thinking that contrary to popular opinion, the exhaust manifold life will be extended, my theory is, the insulation will slow the cooling and even more evenly cool the manifold with the engine off, this reduces the thermal stress brought on by constant change of hot to cold. my own experience in this is my cousin's truck broke an ear off the head where the manifold bolts to it, what happened is a 4th gear high load burnout, the truck stalled and we could not restart it fast enough, the manifold rapidly cooled from 600+ degrees and shrank enough to break the mounting tab. as for rust, i live in cali so its not much of a problem, though i do not think that moisture is really much of a concern, durning operation the heat will evaporate the water plenty fast to not have any issues, so it is constantly drying, when the engine is shut down, what ever moisture is still left in the wrap will evaporate quickly with the remaning heat, and when the truck is not running the water should not be able to reach the manifold anyways and so should not be a convern. in all i am satisfied with these early results, i will report back more as i learn more. i do have one thought i want input on, heat products suggests 50% overwrap, to me it is looking thin especially compared to heat products turbo blanket, i have heard that too much insulation will cause problems, but no explanation as to what problems, anyone have any ideas? im thinking about wrapping it up a little thicker for more insulation. inputs please.



now for the other side of the turbo, i have spent a few dollars upgrading some different parts, i installed an afe drop in air filter in the factory box, i also installed a while ago a tag I that seemed to help but not tons, recently i installed the afe torque tube, this i modified to fit the tag, the results of that have been impressive. i think it is the combo of the torque tube and the tag that made a difference. what i have noticed is significantly lower cruise egts, and a lot slower rise in egts during acceleration. also the turbo comes on noticeable faster. i have a hx35 14cm2 non-wg housing. before intake work cruise egts were 600 to 700*, after install its now 500 to 600*, all of that depending on ambient temps. have only had one tank of fuel with the intake work done, it was up about 1 to 1. 5 mpg, weather conditions have been consistent and not a factor at the moment. its not enough for me though to say solidly that it is effecting that number. i do suspect it is though.





ok so now on to some of my thoughts and ideas for future benifits, up till now my mods, i would say that the cost of the mod vs the gain, while both are small it is probably about the same as a more expensive mods, we will know once i get some better fuel mileage numers.



for the moment this is all i have, i really do want to hear feed back and critiques to my thoughts, ideas, and actions, but be ready for me to defend it, not because i think im right and you are wrong, i just think that if we are forced to defend a position, more of the real truth comes out and we all gain from it.



as i mentioned before anybody else with other ideas for cheap easy mods that will boost performance, please chime in with it so we can all gain from the idea.
 
A true cold air intake is going to help a lot but is hard to achieve if you like your hood.



I need to check into the torque tube by the sounds of your gains.



Stuff I learned from drag racing bikes:



Synthetic oils in everything will help.



Engine ice coolant is no joke, it frees up a little horsepower. Not enough for what it costs but.....



Ceramic bearings rule. If you can replace your wheel bearings with ceramic bearings it will be more efficient. Don't know about an 8,000# truck but on bikes it helps



Weight, weight, weight. How much crap is behind your seat? How about that

milk crate full of log chains sliding around the bed since last November?



Unhooking your alternator and taking a good crap is good for almost a tenth.



Ok back to the real world, if it's 2wd lower the front and or install chin spoiler/air damn to control air drag underneath truck.



Slow down 5 mph. Best mpg gains in the world, couple that with a grandma stoplight takeoff and you've got a slam dunk.



Run the narrowest tire possible at the highest pressure possible.



Check the timing. Miles add up and so does gear lash. Ensure your timing is set for your average cruise speed.



Check the injector pop off pressure and spray pattern. If pop off is not to spec your not getting full potential.



Electric cooling fan and ac delete will reduce paracitic drag, at least for winter months



And last but not least I think a hotter thermostat will help mileage. Used to be 195 degrees was starting to be hot. Now most otr trucks run 200 and the fans don't kick in until 215-220.



YMMV :)
 
Hannick you and I have the same truck except yours is one year newer. What kind of mpg are you getting? My all time best is 22 empty, that was a looong tank. Worst was 14 mpg, empty. In my defense there was this duramax that thought he was fast.
 
A true cold air intake is going to help a lot but is hard to achieve if you like your hood.

with this i was thinking my next mod will be some reflective heat mat on the side of the air box that is facing the exhaust, also planning to install the factory fender snorkel back in to help force the intake of cooler air from outside the engine bay. personally looking at the air box itself i dont think it is all that restrictive, hence my desire to modify, ideally i would like to install an ice cold air box, but the gains at 200 bucks will not pay off fast enough for me at the moment.



also i was thinking about trying to draw air from behind the bumper to the air box, the passenger side air bag sensor would have to be removed or relocated, the battery box will have to be trimmed, and its going to take some work to get around the lower rad. hose and a/c line. looking at it i would imagine that it would take minimum 3" preferably 4" piping to support the airflow needed/desired without getting too much velocity, and for maximum effect the pipe would be insulated from the engine heat.



anyone have other ideas for supplying more cold outside air without it being obvious, i have thought about the firewall behind the air box, but i dont like the idea as i am worried it will take away from the hvac operation, plus there is no good way to connect it to the air box.



I need to check into the torque tube by the sounds of your gains.

i think its worth the 80 bucks, the turbo air guide i think only helps it out.



Stuff I learned from drag racing bikes:



Synthetic oils in everything will help.

thats for sure, i run schaeffer syn, in everything, truck runs really well, their supreme 9000 ful syn high moly 5w-40 oil gave me about 1 to 1. 5 mpg gain.



Engine ice coolant is no joke, it frees up a little horsepower. Not enough for what it costs but.....

i run redline water wetter, will be switching to schaeffers version soon, is that what you are talking about? i like the way it runs in my truck



Ceramic bearings rule. If you can replace your wheel bearings with ceramic bearings it will be more efficient. Don't know about an 8,000# truck but on bikes it helps

i have never seen ceramic bearings for our trucks, probably due to weight as you mentioned, though i can see the gains is it could be done.



Weight, weight, weight. How much crap is behind your seat? How about that

milk crate full of log chains sliding around the bed since last November?

here i dont think your totally on the mark, in racing every once counts, in street use, focus should be paid to rotational weigh and unsprung weight. except the engine, if i were building a daily driver engine i would increase the rotational mass as much as possible, acceleration would be hurt, but once its up and running the increased mass will actually help the engine turnover and propel the truck.



Unhooking your alternator and taking a good crap is good for almost a tenth.



Ok back to the real world, if it's 2wd lower the front and or install chin spoiler/air damn to control air drag underneath truck.

it would work on a 4x4 too but thats sort of contradictive, anything that can push the air around the truck instead of under it will help, i actually tried to talk about this here but i cant figure out how to word my ideas in an ordered fashion.



Slow down 5 mph. Best mpg gains in the world, couple that with a grandma stoplight takeoff and you've got a slam dunk.

another good one, i already drive as slow as i dare which is still too fast for my gearing, also slow easy acceleration while shifting in the power band makes a big difference.



Run the narrowest tire possible at the highest pressure possible.

i have done this too, went from a 16x10 rim with 33 or 35 12. 5 tire to a 16x8 with 285's



Check the timing. Miles add up and so does gear lash. Ensure your timing is set for your average cruise speed.

i just did readjust my timing, was set too low from the last time i was in there, not from wear.



Check the injector pop off pressure and spray pattern. If pop off is not to spec your not getting full potential.

did this as well, installed a new set of injectors recently, saw big gains from it.



Electric cooling fan and ac delete will reduce paracitic drag, at least for winter months

im not sold on the cooling fans, yes i think they work about as advertised, however i ocasionally tow too heavy for them and i dont want to over heat on the grades, when i get in the truck i dont stop till i reach my destination



And last but not least I think a hotter thermostat will help mileage. Used to be 195 degrees was starting to be hot. Now most otr trucks run 200 and the fans don't kick in until 215-220.

have you done something like this? ive been thinking about it for my truck and have been wondering, probably would not work without the fan engagement temp being adjusted, i do know the powerstrokers claim significant increases, eventually im sure i will get around to doing it to ours but have not yet to date.



YMMV :)



Hannick you and I have the same truck except yours is one year newer. What kind of mpg are you getting? My all time best is 22 empty, that was a looong tank. Worst was 14 mpg, empty. In my defense there was this duramax that thought he was fast.



mine has always been a little low, when i bought the truck at 150k miles i got between 16 and 17, average for the year in 2008 was 16. 03 mpg, in 2009 i installed 315 tires and the mileage dropped to 15. 48 mpg for the year. lost 2 mpg after installing the tires. 2010 fuel mileage was 14. 18 for the year, this was the first full year with the 315's. finally this year, due to changes in commute and other factors its been a little hard to see exact changes but, jan. was 14. 81, feb. 15. 12, march 14. 05, april was 14. 98, easter i installed the smaller rim and tire combo, may, june, july mileage was 13. 74, 13. 07, 14. 73 mpg respectivly. however these months saw a lot of heavy trailer towing, and if not towing it was driven about a mile a day, not very good for fuel mileage. in this time i have upgraded the fuel system, these made a big difference, but could not really be seen till august, which was 15. 04 mpg, mid august i started school and so i now have a good and consistent commute for acurate mileage. september had some of my best mileage at 16. 39 mpg. my best all time high was 17. 6 mpg, my low is somewhere around 10 that was with a trailer and my buddy who was driving had a heavy foot. my best monthly high is 16. 68 mpg the lowest 13. 74 mpg. i can post my complete records if you would like to look at them more closely, also all of these number are uncorrected, the speedo and odo are off by at least 6. 7% or more depending on the tire size.



my goal is to break into the 20's probably going to have to switch to 3. 54 gears to do it, but i love playing with these ideas with intake and exhaust along with other small things that can pick up some gains, get enough of them to work together and you can have some real gains that make it all worth while. its a bit of a science experiment for me which is what i like to do in my free time.
 
that really didnt add in the way i wanted it to, does it make sense to everyone or should i edit it so its clearer what i quoted and what my responce was?
 
ok so im wanting to focus on heat for the moment, i have just read and seen some ideas about other things to insulate, they are in order of air flow, intake tube, charge line to cac, charge line to intake, and i think even the intake was wrapped, how do these things sound to you? i could see the intake tube and the charge line to the intake horn but not the charge line to the cac, i think there is too much heat in there. thinking though maybe not when you are crusing (most of the engine hours) it could be getting heat soak then, im positive at full power it might be an issue. thoughts?



also back to the exhaust manifold, im probably going to install another layer of wrap, i was also wondering what affects plain old aluminum foil might have on everything when combined with the wrap. almost all heat managment products are aluminized, is there anything special to it, or could i wrap a couple sheets around my insulation for a small gain. my reason for asking is admittidly while so far i like my precieved gains, it does look ugly, im thinking if im slow and careful i might be able to make it a little prettier with the foil, at least it would be shinny which is a good thing, but im not going to add it if its not really going to help me, and for those who are concerned, i can be a sticler about how things look, mainly does it look professional, if i do add some alum. foil it would not be a cheap looking wrinkle job.
 
I bought my stuff from ATP. The guy there really knows his stuff when it comes to insulating things. I think his site is Advanced Thermal Products

He actually does Dodge wraps as more of a sideline. He is mostly in the aerospace and industrial end of things, and happens to own a Dodge...

While he sells turbo and exhaust wraps (not cheap) he will have some insight for you.

Be forewarned... he is a bit of a weirdie... in a good way, though.
 
wrapping the exhaust will keep the gasses expanded and help with spooling the turbo. . not sure if you would be able to measure the increase as I would think it wold be a small increase in engine response, not necessarily max hp...

At the same time, it would keep underhood temps down some. . On an intercooled engien though, I would think the CAC would have enough efficiency to scrub off that little bit of exrta heat being generated by the unwrapped pipe. maybe not...

Too bad we dont have a couple of mules and dynos available for testing. .
 
I bought my stuff from ATP. The guy there really knows his stuff when it comes to insulating things. I think his site is Advanced Thermal Products



He actually does Dodge wraps as more of a sideline. He is mostly in the aerospace and industrial end of things, and happens to own a Dodge...



While he sells turbo and exhaust wraps (not cheap) he will have some insight for you.



Be forewarned... he is a bit of a weirdie... in a good way, though.



The ATP ex manifold blanket will insulate some noise and some underhood temps but I don't think as much as the header wrap.
 
Bob, it's hard to say... I have header wrap on my down pipe between turbo and cat, and it still gets HOT! I'd like to see testing between header wrap and a manifold blanket/shroud.
 
Did you persue this any further?



i have done more, i wrapped my intake box and tube to the turbo, made a snorkel just like the factory one, put a small amount of adhesive wrap inbewteen the radiator and intercooler, also a little on the charge pipe to the cac, completely wrapped the charge pipe from the cac to the intake, and a little on the horn itself (will probably do more). in all i am happy, no fuel mileage numbers that i can claim but the engine seems to run a little better. more responsive and more consistent day to day.



wrapping the exhaust will keep the gasses expanded and help with spooling the turbo. . not sure if you would be able to measure the increase as I would think it wold be a small increase in engine response, not necessarily max hp...

At the same time, it would keep underhood temps down some. . On an intercooled engien though, I would think the CAC would have enough efficiency to scrub off that little bit of exrta heat being generated by the unwrapped pipe. maybe not...

Too bad we dont have a couple of mules and dynos available for testing. .



it seems exactly as you say as far as wrapping the exhaust. no max gains that i can feel but more responsiveness and more bottom end. the under hood temps are way down and i think thats a good side effect from it. all of the wrapping really made a difference in helping the different components do their job.



Are you still running the factory ex manifold?



i dont know if that was to me, but i am yes.



The ATP ex manifold blanket will insulate some noise and some underhood temps but I don't think as much as the header wrap.



i agree here, i wrapped mine tight and i am happy with the results, a blanket i dont think is as effective. i am tempted to do both though to keep more heat in the exhaust, but that might not really be worth it.
 
i forgot to mention too that i am planning on doing some work on the inside of the air box. i need to trim and "tune" the snorkel and then i am going to put some bondo inside and shape the box for better flow. i think that with the bondo it will reduce the volume some and increase velocity. that combined with smoother walls and less turbulance will increase flow in the stock box, at least i think it will. ill let you know what it does when i get time to do it and test it.
 
The 12 valve manifold doesn't flo as well as the aftermarket

Pieces

I did experiment on an egr version, spent way too

Many hours porting. good results though. I added a mild toque

Plate at the same time the owner reported back the egt's were lower

On the cajon pass towing at a higher speed than previosely. On my

94 I spent a couple hours porting before installing every little bit helps
 
The 12 valve manifold doesn't flo as well as the aftermarket

Pieces

I did experiment on an egr version, spent way too

Many hours porting. good results though. I added a mild toque

Plate at the same time the owner reported back the egt's were lower

On the cajon pass towing at a higher speed than previosely. On my

94 I spent a couple hours porting before installing every little bit helps



your talking about the exhaust manifold? i agree, eventually i will get a good aftermarket one, for now though its working and i cant afford a new one.
 
your talking about the exhaust manifold? i agree, eventually i will get a good aftermarket one, for now though its working and i cant afford a new one.



Pull your stocker and port away. You will spend a bunch of time and have to get creative in your tool choice but it is a low $ mod if you have the time and tools.
 
i have thought about it, problem is time. i have too much going on and the truck cant be down that long other wise i would. maybe i will have time this summer but for now it will have to wait.
 
I just put on an ATS ex manifold on my 97 yesterday. I'm always scepticle but this manifold actually works. It lowered my cruise egt about 125 on average and raised boost about 3-4 pounds at cruise. It lowered my spool up time, boost starts about 75-100 rpm before the swap. It seems to have changed my exhaust note a little as well.
 
i have thought about it, problem is time. i have too much going on and the truck cant be down that long other wise i would. maybe i will have time this summer but for now it will have to wait.



Maybe some one local to you can donate a good used manifold for your project;)
 
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