Engine/Transmission (1998.5 - 2002) Value of "special" aircleaner ducting...

[Gary - K7GLD]

Gary, frankly I don't see how that "test" proves any theory of yours. You have yet to get out and work your truck, under load, and report the temperatures. It has already been submitted that a 55 MPH cruise isn't going to yield much of a difference.



Let us know what the difference is when you get out there and really put a load on your truck. The only thing you're doing now is repeating what you've already claimed.

No, I have provided ADDITIONAL proof for the benefit of previous critics who insisted my test equipment and methods were flawed - the SAME critics who NOW must rest all their remaining hopes on the results of a heavy haul/steep grade scenario - and that's OK too, because in about 14 days, I get to yank THAT rug out from under you all as well, I have NO doubt that the heavier towing situation will result in essentially the same results! :-laf :-laf



Get those objections ready, your time is running out! :-laf :-laf

 

[rweis]

I think he is going to take the thermometer "RV'ing" for a week. We'll see what that yields.



Bob Weis

 

[I-6DZL]

Gary the starting point to your thread was to see the actual air temperature going into the turbo... ... CORRECT ???



Does your latest temperature probe have a long enough shank to actually stick through the air filter somehow ? Maybe a pic of the end, please.



Gary nobody doubted you or your readings. LsFarm was simply stating it is better to actually monitor the air temp during the same scenario that our trucks are built for *TOWING, HAULING, WORKING* The way i took he only wanted to see more accurate readings for the above conditions.



While your *MEAT THERMOMETER* may have been accurate enough for around town driving, is it accurate for the above mentions conditions. We'll only know from your findings. *THANK YOU*



G-Day



Curtis

 

[ThrottleJockey]

Hey Gary,



Hasn't this issue already been addressed?



#ad

 

[rweis]

I have a Scotty II with the hole cut an I will find a temperature probe that I can put at the intake end to the Scotty II and drive that around some to see what the input air for the Scotty II is. I will try to find a temp gauge that I can also put a probe under the hood (where a BHAF would be) at the same time so I can get both temps simultaneously under various driving conditions.



Might be a couple of days though, other projects (fuel cooler) has a higher priority right now.



Bob Weis

 

[Gary - K7GLD]

Curtis wrote:

====

Gary the starting point to your thread was to see the actual air temperature going into the turbo... ... CORRECT ???



NO, that is INCORRECT - it is to determine underhood temperature under varying conditions AVAILABLE to the aircleaner and intake tract. I have no safe or easy way to determine turbo inlet temperatures - and given the temperature of air immediately adjacent to the aircleaner, that should be sufficient for my purpose!



Does your latest temperature probe have a long enough shank to actually stick through the air filter somehow ? Maybe a pic of the end, please.



You already HAVE a pic of the end probe, up there in my last picture post!



Gary nobody doubted you or your readings.



HAH!



LsFarm was simply stating it is better to actually monitor the air temp during the same scenario that our trucks are built for *TOWING, HAULING, WORKING* The way i took he only wanted to see more accurate readings for the above conditions.



While your *MEAT THERMOMETER* may have been accurate enough for around town driving, is it accurate for the above mentions conditions. We'll only know from your findings. *THANK YOU*



UMMMm - you musta MISSED my last picture post up above clearly showing the digital remote reading thermometer I used for my last test run... And it WASN'T a damn "meat thermometer" I was using earlier - it's an air conditioner test thermometer used by A/C techs to test A/C temperature differentials



G-Day



Curtis



====



OK guys, I have been largely just been giving you a hard time - hopefully, we are all friends here - and no hard feelings on my part - just a slight annoyance that my methods and motivations should be so agressively questioned and resisted just because some don't like results that differ from long held assumptions!



IF, when I started this test, I had asked in open forum under what driving circumstances special intake ducting to outside air benefitted engine performance, I'll flat out GUARANTEE you the overwhelming response would have been "why, under ALL driving conditions of course!"



Now that THAT seems to have been largely disproved, NOW the cry is, "well, the GREATEST benefit is under HARD work, heavy loads up steep grades, yeah man, that's it"...



Well, even if that WAS true, how often do you actually USE your trucks in those scenarios? Would you REALLY pay the $$$ for a product or mod that only delivers marginal gains over extremely LIMITED conditions that the vast majority of us only rarely see, percentage wise, in daily or towing use?



Face it, the VAST MAJORITY of typical truck operation is lightly loaded around-town and freeway driving - where the special ducting SEEMS shown to be pretty worthless as a performance booster, at least as compared to other commonly used intake filter setups that are far less expensive and physically intrusive to the vehicle!



BUT, in 2 weeks, we'll be towing our 15,000 lb GCWR RV setup over several pretty decent grades on our way to the Oregon coast - and we'll SEE what differences in temperature differentials occur when we do. I suspect precious LITTLE difference from that already seen locally and out on the open road!



And if I'm wrong, I'll simply have to publicly eat my words!



(been there, done that - it ain't fun OR tasty!)



NOW, if any here still question my tools, integrity or methods, these digital remote thermometers are pretty common and inexpensive - why not go buy your own, run lots of tests under varying conditions, document your findings and post them, complete with supporting pictures here on this board. Shucks, I'm SURE you will get enthusiastic welcome and support for your info - just as *I* did...

 

[Lsfarm]

Test Results

Thanks Gary for doing the work to set up a real time reading temp gauge.

Seeing a similar 10* over ambient during your very low power 55 mph test runs verfies your previous data.



Now I'm still very intersted to see what happens when you are pulling a long steep hill at say 55-60mph with 20-30 psi boost, A/c on and the fan clutch engaged. This will be the interesting reading. Even more interesting will be if you get stuck behind an eighteen wheeler doing say 40 mph and you have very little ram air mixing with the heated under-hood air!!



I suspect that you will see about 30* above ambient at 55-60 mph, but this will vary with road and airspeed [head wind or tail wind] Since what you are actually reading is how much the under hood air is heated by all the heating devices [condenser, intercooler and radiator] as the air makes it back to your airfilter.



There is also cool ambient air from the fender-well factory vent hole and air getting in past and around the headlamp. This air will vary in volume with airspeed [ram effect on the front of the truck]. The volume of this cool air will greatly effect your air filter readings. I believe that you could measure a temp drop if you just removed your pass side headlamp. The additional fresh air from the ram effect is probably measurable at the airfilter.



If you read my posts on this thread, the only objection I have had is the assumption that what you are seeing at a 55 mph empty cruise was valid information to base you blanket opinion about cowl induction air intake systems.



NOW that you will have some readings during the more extreme conditions that our trucks can be operated under you will have good data to base an opinion on.



Food for Thought:

Yes most of us use our trucks for mostly light duty transportation, and a cowl induction air intake is probably overkill.

But some people remove the silencer ring just to hear the turbo better, so a cowl induction air intake is just a step up for the turbo-noise crowd. Don't knock it it, it is their truck and hearing.



When a truck makes back-to-back dyno runs with no changes between runs, the results almost always show a measurable drop in HP on the second and third run. This is from preheating the intercooler. Now a few HP drop may not be significant, but it shows that there is a valid reason to keep intake air temps as cool as possible to keep the charge air density as high as possible.



Most people may not care that they loose a few percent HP as the under hood air temps rise, but there is a valid reason to keep the air as cool as possible. Just as 'mspero' stated in a post above, Dodge has not eliminated an outside air duct and air box for cost savings, so there are valid reasons to have cool outside air.



Would you try a run with the fender-well factory hole sealed with duct tape?? I'm very curious just how much this air duct has on your readings.



Your aluminum heat shield may make a measurable difference too, once you have a base line for hill climbing, high boost, fan clutch engaged, then it would be even more interesting to see what you see with the shield removed, maybe you can dispell the belief that the heat shields are usefull too!!. Many folks just install a BHAF and don't make any attempt to shield it from the turbo's heat



If you find only a minimal rise in temps at the air filter with the engine working hard and the fan clutch engaged then all of us who have not spent the $ for a cowl induction system can breath a sigh of relief that we are not running our engines on overheated air. And that a BHAF or AFE Mega filter is not feeding our engines a lot of preheated air.



Looking forward to your data, I hope to have some soon too from my trucks.



When Bob [rweis] gets and posts his date then we will have even more 'food for thought'



Greg L

 

[I-6DZL]

If i had a digital thermometer like yours gary i could have very well gave you all kinds of different readings. Pulling roughly 4k today, which isn't hardly enough for the cummins to break a sweat but still something.



Although i will gladly jump in and offer my readings as well. I plan on pulling the camper down to toledo in a month. If you can or will wait that long i'll have my data as well.



BTW i did not intend on getting your shorts in an uproar by saying Meat Thermometer, it was merely intended to bring a chuckle. I also have A/C thermometers, from when i was a tech.



Curtis

 

[Gary - K7GLD]

No problem Curtis - as I stated, I'm having fun with this, both due to what I am learning from these tests, and then giving some of the diehard guys a bad time.



It hasn't been all that long since I too thought typical underhood temps were higher than what they are checking out to be - but past tests done by others tipped me off, and motivated my own testing done here.



I suspect varying engine types and engine bay layouts contribute greatly to potentially widely varying differences in these type teadings. V8's tend to fill engine bays and block free flow of underhood air, whereas we are sorta blessed with the Cummins, where we get a pretty decent open area surrounding the engine, and free exhausting of underhood heat.



In my case, I have pretty significant power mods that will allow easily maintained road speeds when traveling uphill and loaded, and typically low EGT's as well - and also permit good purging of underhood heat buildup - that's why I expect pretty much the same results towing as around town lightly loaded.



By all means, run your own tests, post them here or in a thread of your own - there's no such thing as too MUCH info - and an open mind and willingness to grasp and accept unexpected or unwelcome results helps too!



Peace!

 

[Gary - K7GLD]

Thanks for the nice post Greg - and sure, as time passes and our RVing trip is completed and data gathered, I can continue to take readings from other underhood areas.



It would be VERY helpful if others here could also do some testing and post their results - might sort out variations, depending on various truck setups...



Yeah, I sure HOPE that BHAF shield is doing SOME good, otherwise I wasted my time there as well - might remove it for a few runs after some of the other runs are complete.



Also thanks for going out on a limb with a guesstimate of temps in a towing situation - it's far better than sitting silently with no committment - then doing the "Monday morning quarterback" bit and picking actual results apart after the fact, as some prefer...



Personally, I predict more like a 15 degree average difference up the grades, primarily due to the Dodge's superior underhood air scavenging ability as mentioned in my previous post.



I figure the intercooler and related temps WILL rise, but that the substantial flow of underhood air will minimize that increase, as long as I can maintain decent road speed - and that usually isn't a problem with my other engine mods.

 

[Lsfarm]

You are welcome

You're welcome Gary.

If you are blessed with no tailwind, and a clear road, you may only have 15* rise. Depends on way too many variables OAT, wind [airspeed], %grade, actual load etc. If you are on only a moderate grade, you may only see a few degrees rise for the intercooler working. Again too many variables



Too bad Bob [rweis] couldn't pull along with you and have a direct comparrison.



Thinking back to last year, towing about 11K GCVW about 18. 5K heading south on I-75, just crossed the Ohio river and started up the long grade into Kentucky. I was in the next to left lane, running about 70 mph, 25psi, 1250 egt. I was passing all the trucks in the two right lanes, mostly keeping up with the left lane car traffic. It was too good to last.



Then an eighteen wheeler pulled out in front of me doing 40 mph, the left lane was solid trafic at about 75 mph. I was stuck. Down into 3rd locked, but too low rpm egt's hit 1400+. I dropped into 2nd, and locked the TC, pulling 1250* 35 psi boost, then the fan kicked in, and the egt's climbed up till I had to drop back on the speed. I was in a real bad spot. There was NO WIND, if anything a tailwind and I was bracketed by trucks.



Needless to say I believe the EGT's climbed like they did due to underhood temps climbing. The engine temp climbed to 220*, I was using a LOT of power! I wish I had good instrumentation for underhood temps at that time, but more I wished for a clear shot up the hill so I could get some air through the grill. !!!



If you get boxed in like I've described, I'll go for underhood temps to climb to as much as 100* over ambient. But again, very extreme circumstances.



Have a safe trip, looking forward to your results



Greg L

 

[CSnyder]

I have already done the test Gary is about to do just for curiosity sake. I also have an indoor/outdoor thermometer and I hooked it under the hood to my BHAF once to see what underhood temps got up to when my coolant temps were hitting 220 and my fan kicked in on a very hot summer day while towing. And anybody that knows me knows I tow VERY heavy with my truck(even hauled entire combines on my gooseneck... . don't ask what they weigh because I don't know... but they are HEAVY) I can't remember what the readings were now but they were outragious and went up drastically under high boost and high EGT's. I totally believe in cowl induction and forced air induction to reduce air temperature going into my motor. I can't wait to purchase a forced air induction hood to help my truck out. Maybe anyone questioning the temps should pop their hood up to the safety catch and run the same hill twice to see what the temp differences are... . you won't believe your eyes! Chris<--on Gary's ignore list

 

[rweis]

On my 02 there is a rubber strip at the firewall lip. It appears that it makes an air seal with the hood. IF you removed that strip would it make the hot air easier to exit from under the hood up along the windshield?



Bob Weis

 

[Lsfarm]

Would you post

CSnyder, would you post some of your temp readings you see ?? Maybe even over a few different situations?



An easy 55-60 mph cruise, then maybe various loads up and down those Iowa 'yo-yo' hills on I-80?



We would be very appreciative and since Gary has you on his ignor list I'm sure someone can quote your readings in a post so Gary can see them.



Thanks for the information



Greg L

 

[Valv]

Interesting thread, a little too long, but interesting.



I always wondered about intake temp before and after intercooler in hot days.



My solution to temp discovery is..... temporarily move temp gauge sending unit from front of grill to BHAF. You will have instant temp reading without "turkey roaster" thermometers involved. Or if you want to waste few $$ buy another sending unit and wire it with a switch in the cab, you can also use it for other issues later.



Now my debate is different. Will air temp from BHAF be higher than after intercooler ?



Let's have a test at 95* outside temp, pulling a 10,000 trailer int stop and go traffic and with air conditioner at full blast.



Anybody interested in this test ?

 

[NIsaacs]

Gary, I think under high power and lower speeds as in up hill pulls you will see some higher under hood temps. However the higher temps will not change your motors power out put enough to ever tell the difference. You will also not see any difference in EGT's under full power with the higher under hood temps.



I have driven big trucks for years with outside mounted air cleaners and have seen no difference in power or EGT's when under full throttle. If the temperature is 100* or 20* below zero the full power EGT's are the same.



If you were to put the trucks on a dyno under this temperature extreme there may be a small difference but you can't tell by driving them. However under cruise power or cool down you can see a difference in EGT's. Since EGT's only matter under full power, cruising doesn't count.



Getting back to high speed driving and under hood air flow, I have noticed on my transmission temp guage (I have a 6spd) that at 65 mph running empty or loaded it will get up to 180*. This temp seems to come from heat sink off the engine more than the transmission itself, cuz at 75 mph loaded or empty the trans temp goes down to 140*. Maybe the air fow at higher speeds?



On the motors in our trucks, the higher the exhaust manifold temp gets,up to a point, the better the turbo works, as in more boost. This is because the head has no water jacket next to the exhaust ports. This was done for cooler water temps and higher exhaust temps, and better turbo spool.



So I guess what I am saying is, I agree, intake temps don't make much difference under full power.





"NICK"

 

[pro99]

Gary, I think under high power and lower speeds as in up hill pulls you will see some higher under hood temps. However the higher temps will not change your motors power out put enough to ever tell the difference. You will also not see any difference in EGT's under full power with the higher under hood temps.



I have driven big trucks for years with outside mounted air cleaners and have seen no difference in power or EGT's when under full throttle. If the temperature is 100* or 20* below zero the full power EGT's are the same.



So I guess what I am saying is, I agree, intake temps don't make much difference under full power.





"NICK"

WTF?



Well then NICK why do we have a intake temp sensor on our motors then if air temp doesn't matter? The hotter the air is at the temp sensor the less fuel it injects. That why we put the temp sensor in the air cleaner. The cooler the sensor the more fuel it gets. Less fuel means less power. My dad is a retired truck driver from 29 years till 2 years ago temps do matter. Hell lets get ride of the intercooler then if temps don't matter. It would be nice to see someone put the engine temp sensor in the hose after the filter on a scotty and a BHAF then see what the temp is.

 

[CSnyder]

Greg, I would love to give you some readings when I get my truck back up and running this week, but I only ran the thermometer for a few days for curiosity sake and never recorded any readings. I just remember them being very high as I pulled the hills with about 33 pounds of boost and 1300 degrees on the pyro. I will have my new transmission in on Monday and will be on the road again Tuesday and will try to find time to get the thermometer set up again before I head out. We have been seeing 80 degree weather and I run A LOT of 8 and 12 degree hills in my area living next to the Mississippi and I run those hills a couple times a day... of course I do it at WOT! I'll post back if I can get you some readings so you can pass them onto Gary. Later, Chris

 

[NIsaacs]

Geeez, Proturbo easy, I didn't say intake manifold temp didn't matter, and on naturally asperated motors the air temp at the filter does matter. However the temp after the turbo and after the intercooler doesn't react to the airfilter temp much. Then after it is burned in the motor the EGT's react very little to the air filter temp. That is all I said.





"NICK"

 

[pro99]

Oops sorry Nick just got caught up in all the post. I think the cooling down the temps is really in the intercooler more than say the air cleaner. Someone chime in on this for me for what I am about to say. It's the turbo it's self that raises the temp from the sheering of air when it hits the impeller up to 300 degrees or more someone chime in? I think we need to look more after turbo than before, but we do need to get cooler air to start with. We need to get more air to the intercooler to cool down intake temps. But you got to start were you can and that is the air cleaner first. I had the Scotty II, mega canon, and a stock air box with a k&n with 3 two inch holes cut in the bottom. I will say this out of all 3 the only one that lowered my egt's the best under full power and loaded with an 8500 trailer was the Scotty II. I will say that in all my test or playing around that it only lowered my egt’s by 45 to 47 over the other setups. This is no bull and I can prove it. I did not check this out in the hills yet.