Cummins exhaust and air intake
Tim Dolan
automatic, 355 rear end. Luv the truck.... but dissappointed in the MPG.
Finally had it checked/dyno'd at Cummins ...results everything within specs
including the 13.5 MPG.
Had a 4" exhaust system put on and a high volume air intake box installed along
with a fuel boost pump because the original lift pump was tested to be bad.
Just got back from a trip with camper and MPG is less than MPG with camper
before the additions.
Here's my question. If I had a stock air intake box and stock exhaust and then
opened up the exshaust and opened up the air intake doesn't the engine have to
be adjusted for this?? What would cause the enging to be more efficient if it
was originally set up for stock intake air amounts and exhaust.
Obvioulsy, I'm not a mechanic but help me anyway.
Tim,
Looking to expand Seniors (55 + ) Daytime Pool League
MAX340
>including the 13.5 MPG.
Not sure how they can "spec" an MPG figure, since this is due to driving
conditions and the driver. More info about what you are doing and the
conditions while you are doing it would help in figuring out if the 13.5 is
unreasonable. Personal experience tells me that around town and "beatin it"
gets me 13.5-14.5MPG avg. Long trips I get 18.7-19.8MPG avg.
>Here's my question. If I had a stock air intake box and stock exhaust and
>then
>opened up the exshaust and opened up the air intake doesn't the engine have
>to
>be adjusted for this??
No.
>What would cause the enging to be more efficient if it
>was originally set up for stock intake air amounts and exhaust.
A diesel engine takes in the same amount of air on each revolution, no matter
how fast it turns. The only limitation is the intake and exhaust. By making the
delivery and removal of air easier, you have increased the efficiency of the
engine, particularly at higher RPM, since now it is assured of getting 100% of
its intake charge each time.
However, if the original setup already provided enough air to burn all the
injected fuel in all RPM ranges, making it able to move more air will not
necessarily result in an increase in power. You may want to look into power
chips for the injection pump, or injectors, for added power.
Max
The mention of Tom Bonini and EG Powers in this line is simply to see if they
will jump through the hoop and head off for more spin.
Proud supporter of the Tom and Eric show!!!!
Jerry
Tim I think your trying to compare your diesel to a gas engine. As is
from the factory the Cummins gets plenty of intake air with the stock
air box. I'm not sure what you mean by "High Volume" air box unless
your talking about the Scotty system and if so then there is no
advantage with a stock engine. As for the 4 inch exhaust system there
are people on both sides of this but personally I don't see any gains
from the 4 inch on a stock engine except to maybe lower the exhaust
temperatures a little. You need to be a little more specific about your
mpg, loaded, unloaded, city, freeway and so on. One thing is for sure
and that is if your boost pump is going out and you know it you had
better get that changed right away before it's failure causes a
injection pump failure because your talking big dollars then.
Jerry
Roy
doesn't sound quite right if you are getting 13.5mpg light. I'll get a range
0f 17-19 light on my 2K 2500 4X4 with 4:10's. Might drop to 15 in the city.
What did Jannetty's people have to say about it?
Also how are you computing the mpg? Don't use the on board toy. Do it the
old fashion way, and do the miles and the gallons.
Roy
"Tim Dolan" <timseni...@aol.com> wrote in message
news:20020721135736...@mb-fc.aol.com...
Tim Dolan
Jerry, I did what I did because it was recommended to improve performance AND
mpg. I'll ask more questions of the shop that did the work.
As is
>from the factory the Cummins gets plenty of intake air with the stock
>air box. I'm not sure what you mean by "High Volume" air box unless
>your talking about the Scotty system and if so then there is no
>advantage with a stock engine.
They called it a new "cold air box". Essentially, it replaced the stock air
intake plastic box with a completely exposed air filter wrapped in a K & N pre
filter. Believe me, it draws in A LOT of air.
As for the 4 inch exhaust system there
>are people on both sides of this but personally I don't see any gains
>from the 4 inch on a stock engine except to maybe lower the exhaust
>temperatures a little. You need to be a little more specific about your
>mpg, loaded, unloaded, city, freeway and so on.
Jerry, there isn't much that I can say. I can drive fast. I can drive slow.
City. Freeway. With the camper without the camper. I've gotten between 10.8 and
14.2 MPG. I've never gotten 15mpg !!!!
One thing is for sure
>and that is if your boost pump is going out and you know it you had
>better get that changed right away before it's failure causes a
>injection pump failure because your talking big dollars then.
Yes, I did. You' right about that. Thanks.
>
>Jerry
Tim Dolan
Roy, I've got Michlen LTX A/S LT 218/85 R16 tires.
Something
>doesn't sound quite right if you are getting 13.5mpg light. I'll get a range
>0f 17-19 light on my 2K 2500 4X4 with 4:10's. Might drop to 15 in the city.
>What did Jannetty's people have to say about it?
The counter person thought that my MPG was low but the owner said that because
of the weight and drag of the duallies, fenders,
quad cab, etc that my MPH was not bad.
>
>Also how are you computing the mpg? Don't use the on board toy. Do it the
>old fashion way, and do the miles and the gallons.
>
Yes, because the truck is in metric I multiply the kilometers by .62 and then
divide by the gallons used.
Hogan Whittall
>
> As is
> >from the factory the Cummins gets plenty of intake air with the stock
> >air box. I'm not sure what you mean by "High Volume" air box unless
> >your talking about the Scotty system and if so then there is no
> >advantage with a stock engine.
>
> They called it a new "cold air box". Essentially, it replaced the stock
air
> intake plastic box with a completely exposed air filter wrapped in a K & N
pre
> filter. Believe me, it draws in A LOT of air.
>
His point was, and still is, it's drawing no more air than the stock airbox
since you have a stock engine. The stock airbox and filter aren't
restrictive until you starting making the big power.
--
Hogan Whittall
1997 Dodge 2500 - Cummins, NV4500, etc
1982 Jeep CJ-7 - Chevy 3.8 V6, T5, etc
Roy
those fenders sticking out don't help. What do you get around town?
Roy
"Tim Dolan" <timseni...@aol.com> wrote in message
news:20020722091618...@mb-ba.aol.com...
Tim Dolan
>since you have a stock engine. The stock airbox and filter aren't
>restrictive until you starting making the big power.
>
Thanks Hogan, but my point was and still is, is to simply answer his question
as to what I did. Thanks for stepping in though.
Tim Dolan
>those fenders sticking out don't help. What do you get around town?
I get 11+ to 12+.
Coming home from Canada (Quebec) on interstate 91, with the camper on the
truck, I took it out of overdrive and set the cruise on 70. It held at 70
steady as a level road.
I just got fuel and it calculated out to be 10.8 mpg.
Roy
Wow!! I was getting a little less than that with my 2K 4X4 V10 with 4:10's
Don't blame ya for being a little upset. How many miles on it?
You probably should go to www.turbodieselregister.com and see what those
folks have to offer. Let us know what you come up with. Sorry I couldn't
have been more help.
Roy
"Tim Dolan" <timseni...@aol.com> wrote in message
news:20020722155752...@mb-ba.aol.com...
Jerry
Tim 11-12 mpg with a cab over camper isn't all that bad in my opinion.
The last cab over I had I got 18-19 with it on the truck as long as I
was in town and running around at city speeds. Seems the weight just
didn't matter to the Cummins but as soon as I hit the open road and ran
it up to 65-70 mph I dropped to 12-13 mpg and in a head wind I could get
as low as 9-10. With the camper you have a lot of wind resistance above
and to the sides of you and I see no way of over coming that except to
slow down. If your getting 11-12 with the camper off the truck then
there is a problem.
BTW, if I were in a position to hold 70 mph with a cruise control I
would leave it in 4th gear lockup for better fuel economy. Of course if
I dropped in speed and rpm then I would turn the overdrive off but at 70
mpg and not lugging, I'd personally leave it on.
Jerry
AC458
>Coming home from Canada (Quebec) on interstate 91, with the camper on the
>truck, I took it out of overdrive and set the cruise on 70. It held at 70
>steady as a level road.
>I just got fuel and it calculated out to be 10.8 mpg.
>
>Tim,
>
I get 17 mpg with an 8 1/2 Lance camper and 10,500# GVW......22 pulling an 18'
carhauler empty at 65 mph. Worst was pulling an empty 14' Pace trailer into a
sub-zero headwind...12.7 Heaviest load - about 18,000# (camper, loaded Pace and
waverunner) 14 mpg through the rockies in the summer heat.
That AT might be killing your mileage.
4:10 gears??
01 Dodge Cummins QC HO 6sp
Tim Dolan
>Tim, you mentioned a camper in your post - is the 13.5 mpg with or
>without it?
Greg, it's 13.5 without a camper.
How many miles on the truck? Has it always been this way
>or is this a recent development?
60,000 miles and yes, it's always been this way. And the dealer, and Cummins,
and a performance shop says thsat 13.5 MPG is not all that bad.
>
>I hate to say it, but if you are only getting that kind of mileage
>WITHOUT the camper, there is still a problem that is not yet properly
>diagnosed and all you did was try to put a band-aid on it with the
>intake/exhaust mods.
>
>Greg
>
That's how I feel Greg, but the feedback that I'm getting is not supportive.
Tim Dolan
>Wow!! I was getting a little less than that with my 2K 4X4 V10 with 4:10's
>Don't blame ya for being a little upset. How many miles on it?
60,000.
>You probably should go to www.turbodieselregister.com and see what those
>folks have to offer. Let us know what you come up with. Sorry I couldn't
>have been more help.
>
>Roy
>
Tim Dolan
>The last cab over I had I got 18-19 with it on the truck as long as I
>was in town and running around at city speeds. Seems the weight just
>didn't matter to the Cummins but as soon as I hit the open road and ran
>it up to 65-70 mph I dropped to 12-13 mpg and in a head wind I could get
>as low as 9-10. With the camper you have a lot of wind resistance above
>and to the sides of you and I see no way of over coming that except to
>slow down. If your getting 11-12 with the camper off the truck then
>there is a problem.
Jerry,
I have never gotten above 14 MPG with this truck...period.
>BTW, if I were in a position to hold 70 mph with a cruise control I
>would leave it in 4th gear lockup for better fuel economy.
I'm not sure whate you mean. What is 4th gear lockup? Is that with the
overdrive off or on?
Of course if >I dropped in speed and rpm then I would turn the overdrive off
but at 70
>mpg and not lugging, I'd personally leave it on.
>
It can hold 70 on pretty level interstates but topography like from Canada down
through Maine into Vermount it will only hold Cruise at 70 if the overdrive is
off.
>Jerry
Tim Dolan
>18'
>carhauler empty at 65 mph. Worst was pulling an empty 14' Pace trailer into
>a
>sub-zero headwind...12.7 Heaviest load - about 18,000# (camper, loaded Pace
>and
>waverunner) 14 mpg through the rockies in the summer heat.
>
>That AT might be killing your mileage.
Yeah, maybe so.
>4:10 gears??
No. 355 gears
>
>
>01 Dodge Cummins QC HO 6sp
>
>
>
>
RedNeck TookOver Hell
trying to feed you BS
Diesel Power
running 65 mph. Running biodiesel only costs me 2mpg. You should be
floating right around 20, give or take. I'd say find out why the mileage is
so low, and don't take "it's normal" for any kind of an answer. If I got
your mileage, I'd be pissed. I can do that with a V10, and get the sports
car power to go with it.
Bryan
--
1975 Mercedes 240D
1988.5 Suzuki Samurai Hardtop (for sale)
1999 Dodge Ram 2500 Cummins Turbodiesel
2002 Saturn SC2
Yanmar diesel tractor
"Tim Dolan" <timseni...@aol.com> wrote in message
news:20020723150020...@mb-mv.aol.com...
Jerry
>
> That is a load of bull. I get a full 10 mpg better than you on the highway,
> running 65 mph. Running biodiesel only costs me 2mpg. You should be
> floating right around 20, give or take. I'd say find out why the mileage is
> so low, and don't take "it's normal" for any kind of an answer. If I got
> your mileage, I'd be pissed. I can do that with a V10, and get the sports
> car power to go with it.
>
> Bryan
Six wheels on the ground, auto trans, 3:55 rear end is what he has but
20 mpg might be a little stretch. However unloaded he certainly should
get better than 13.5 but the more I read his posts the more I think
there is nothing wrong with the truck. He is doing 70 mph, in hill
country with overdrive turned off and cruise control turned on. The
truck is now trying to hold 2,900 rpm up and down hills with a load, no
way are you going to get decent mileage under those conditions. It's
normal probable meant the engine checks out okay. I think he was sold a
bill of goods with the 4 inch exhaust and the K&N filter setup though,
especially the latter.
Jerry
Tim Dolan
>trying to feed you BS
>
Ok, thanks.
Tim Dolan
>running 65 mph. Running biodiesel only costs me 2mpg. You should be
>floating right around 20, give or take. I'd say find out why the mileage is
>so low, and don't take "it's normal" for any kind of an answer. If I got
>your mileage, I'd be pissed. I can do that with a V10, and get the sports
>car power to go with it.
>
>Bryan
>
Yup, Bryan that's what I'm trying to do.
Diesel Power
running 65 mph , or the maximum posted limit, whichever is lower, driving
between Decatur, TX and Denver, CO in my truck. The route I take has me
driving over Raton pass, which is a hard 6% grade on the NM, CO state line,
and is a very hilly drive - generally uphill the whole way. My
understanding is that he is getting this 13.5 mileage figure empty as well.
I don't expect him to get my figures with the auto and extra two wheels
worth of rolling resistance, and the extra bit of speed. However, a 10 mpg
drop is way outta line.
Now getting that loaded, out of OD, running 70, in hilly terrain, and with a
heavy load, then the figure would be correct. The Cummins does NOT like
running north of 2000 rpm while cruising.
So far, the worst I've logged was 17 mpg with a loaded car trailer, still
holding to my maximum 65 rule. My last trip to Austin logged 18 with a
Mercedes on the trailer.
Bryan
--
1975 Mercedes 240D
1988.5 Suzuki Samurai Hardtop
1999 Dodge Ram 2500 Cummins Turbodiesel
2002 Saturn SC2
Yanmar diesel tractor
"Jerry" <jerr...@earthlink.net> wrote in message
news:3D3E27B7...@earthlink.net...
RedNeck TookOver Hell
get 13 pulling a trailer and having a cab over camper over the "hills" to
Boise.
Yeah, I got the dually, auto., & 4 X 4 and yeah, I run around 70
.>well.
Roy
people,super work. Cummins Northeast is the name. I'd give them a call and
make an appointment.
They are about 20 minutes north of the RI/MA line.
Here's the phone # 1-781-329-1750
Maybe there is one closer?
Roy
"Greg Surratt" <glsu...@att.net> wrote in message
news:0gjrjuks1evsm9ese...@4ax.com...
> On 23 Jul 2002 19:00:20 GMT, timseni...@aol.com (Tim Dolan) wrote:
>
> >60,000 miles and yes, it's always been this way. And the dealer, and
Cummins,
> >and a performance shop says thsat 13.5 MPG is not all that bad.
>
> Ya know, Tim, I could understand a "performance shop" saying that
> because those are the guys that are willing to sacrifice mileage for
> speed.
>
> I could understand the dealer saying that because their diesel
> mechanic may be "trained" but not "experienced".
>
> But shame on Cummins. They should know better. Hell, I had an
> International Cabover Class 8 pulling a 13'6 high, 42' moving van that
> did almost as good as your pickup running empty.
>
> If I remember right, you are in New England? Have you checked with
> another Cummins factory dealer not in the same franchise chain as the
> first one you took the truck to?
>
>
> Greg
Diesel Power
with my typical load. I *know* that my loads are not all that heavy for
what I drive. C'mon man, 10.8 mpg running loaded with a similar rig to
yours, where you're getting 13 in the same type of conditions? Don't you
get the point that we're getting at?
Bryan
--
1975 Mercedes 240D
1988.5 Suzuki Samurai Hardtop
1999 Dodge Ram 2500 Cummins Turbodiesel
2002 Saturn SC2
Yanmar diesel tractor
"RedNeck TookOver Hell" <mopa...@aol.comedyhour> wrote in message
news:20020724035049...@mb-fy.aol.com...
Jerry
>
> But shame on Cummins. They should know better. Hell, I had an
> International Cabover Class 8 pulling a 13'6 high, 42' moving van that
> did almost as good as your pickup running empty.
>
> If I remember right, you are in New England? Have you checked with
> another Cummins factory dealer not in the same franchise chain as the
> first one you took the truck to?
>
> Greg
I agree with you 100% if Cummins actually said 13.5 mpg unloaded is
normal. Kind of wondering if they might have actually been talking
about the engine itself checking out normal with no problems
noted?????? I didn't know Cummins could run a mpg test for you.
Jerry
Roy
hour and factor in the wind and rolling resistance. It isn't to the tenth
but it's darn close.
Roy
"Jerry" <jerr...@earthlink.net> wrote in message
news:3D3EE857...@earthlink.net...
RedNeck TookOver Hell
Tim Dolan
>worth of rolling resistance, and the extra bit of speed. However, a 10 mpg
>drop is way outta line.
>
>Now getting that loaded, out of OD, running 70, in hilly terrain, and with a
>heavy load, then the figure would be correct. The Cummins does NOT like
>running north of 2000 rpm while cruising.
>
Thanks Brian,
The running out of OD in cruise control was an experiment.
But, if 10.8mpg is reasonable under those conditions: why wouldn't the MPG go
up significantly when I run below 2000rpm empty?
Tim Dolan
>get 13 pulling a trailer and having a cab over camper over the "hills" to
>Boise.
>Yeah, I got the dually, auto., & 4 X 4 and yeah, I run around 70
>
That's what get day to day empty.
Tim Dolan
>Ya know, Tim, I could understand a "performance shop" saying that
>because those are the guys that are willing to sacrifice mileage for
>speed.
>
>I could understand the dealer saying that because their diesel
>mechanic may be "trained" but not "experienced".
>
>International Cabover Class 8 pulling a 13'6 high, 42' moving van that
>did almost as good as your pickup running empty.
>
>If I remember right, you are in New England? Have you checked with
>another Cummins factory dealer not in the same franchise chain as the
>first one you took the truck to?
>
Yes, I'm in New England. No, I don't know of any Cummins factory
dealer. It seems that Cummins really cops out here by saying how they don't do
much with pick-ups etc and they kind of dump it on Dodge.
I'll look to see about another Cummins dealer. I'll have to go to
another state probably, but Connecticut isn't that big.
Diesel Power
seems more in line with what you should be getting loaded to the gills.
Bryan
--
1975 Mercedes 240D
1988.5 Suzuki Samurai Hardtop
1999 Dodge Ram 2500 Cummins Turbodiesel
2002 Saturn SC2
Yanmar diesel tractor
"Tim Dolan" <timseni...@aol.com> wrote in message
news:20020725082337...@mb-fi.aol.com...
Ashley Holgate
set for average power but you can turn it up or down and get results of more
power and/or more fuel mileage.
I have a 01' HO QC Long box w/3:54(5) gears and a six speed. Here are my
figures for mileage.
First I have a TST Stage 3 installed with a remote from 0 - 9, zero being
stock or off. With it on zero or off I and babying the truck doing about 65
going from Portsmouth, NH to our farm in Ithaca, NY traveling on 95>88>206
which is all hill I get from 18 - 20. Now when I turn on the remote and set
it to 1 which changes the timing I will get about 22 - 24 MPG. My best
mileage is from Rochester NY to Syracuse, NY doing 70 (w/255-85-16 Dunlop
Rover AT's) I got 26 on cruise. Now I have found that cruise hurts me as it
will do everything it can to maintain speed. When I am in control I let the
truck loose some speed and when I see a hill I gently and slowly increase
throttle and then let it slow down gradually. Maybe my driving style but I
have had two Cummins my first being a White 99' Sport QC Long Box and I got
the same mileage but this was with an automatic and same tires.
Ashley Holgate
"Tim Dolan" <timseni...@aol.com> wrote in message
news:20020725083123...@mb-fi.aol.com...
Tim Dolan
>long fifth wheel. I run a consistant 60 mph without Overdrive, so I'm
>running about 2200 rpm.
>
>The absolute worst mileage I've ever gotten with my truck was 10.72
>mpg for a 272 mile stretch from Amarillo Texas to Calumet Oklahoma. I
>attribute this low mileage to the fact that the wind doesn't blow, it
>SUCKS the MILEAGE out of a rig in Oklahoma.
>
>Same truck and trailer got 14.98 for 443 miles between Ephrata, PA and
>Oxford, MA.
>
>Without the trailer, the best I've ever gotten was 21.42 mpg for 482
>miles from Haw River, NC to Norfolk, VA.
>
>Average is about 12 mpg with the trailer on road trips.
>
>Average is about 19 mpg without the trailer on road trips.
>
>I'll stand by my recommendation to find another Cummins shop run by a
>different franchise owner to have them check the truck out.
>
>Greg
Greg, I've taken your recommendation. I have an appointment for August 12th. I
wanted to wait intill the new Fuel pump was installed (warantee)
Tim Dolan
>seems more in line with what you should be getting loaded to the gills.
>
>Bryan
>
Yup,
that's why I'm going to another Cummins shop to get another olpinion.
Tim Dolan
>Has anyone looked into the timing of this motor? I know that the timing is
>set for average power but you can turn it up or down and get results of more
>power and/or more fuel mileage.
ashley,
I didn't know it has "timing" as such..
>
>I have a 01' HO QC Long box w/3:54(5) gears and a six speed.
HO ? QC quad cab. 3:54(5) gears?
Here are my
>figures for mileage.
>
>First I have a TST Stage 3 installed with a remote from 0 - 9, zero being
>stock or off.
What is a TST Stage 3? remote?
With it on zero or off I and babying the truck doing about 65
>going from Portsmouth, NH to our farm in Ithaca, NY traveling on 95>88>206
>which is all hill I get from 18 - 20. Now when I turn on the remote and set
>it to 1 which changes the timing I will get about 22 - 24 MPG. My best
>mileage is from Rochester NY to Syracuse, NY doing 70 (w/255-85-16 Dunlop
>Rover AT's) I got 26 on cruise. Now I have found that cruise hurts me as it
>will do everything it can to maintain speed. When I am in control I let the
>truck loose some speed and when I see a hill I gently and slowly increase
>throttle and then let it slow down gradually. Maybe my driving style but I
>have had two Cummins my first being a White 99' Sport QC Long Box and I got
>the same mileage but this was with an automatic and same tires.
>
>Ashley Holgate
Tim Dolan
>Here's hoping the fuel pump solves the problem and you don't need
>anything else.
>
>Greg
>
I'm still working a a tank of fuel since the cruise control experiment. It's
looking pretty good. The inbetween boost pump on maintains 8psi I think, and
I'm a little over 500km at the half tank mark. As you know it's not half a tank
because it goes down really fast now. But during the experiment I think it was
less than 400km at the half tank mark.
Tim Dolan
>I'm still working a a tank of fuel since the cruise control experiment. It's
>looking pretty good. The inbetween boost pump on maintains 8psi I think, and
>I'm a little over 500km at the half tank mark. As you know it's not half a
>tank
>because it goes down really fast now. But during the experiment I think it
>was
>less than 400km at the half tank mark.
>
>Tim,
OK, on that tank I got 15.2 MPG that's the best ever. But this tank may be back
to where it was. May or may not hit 400km at half tank mark. I don't think I,m
driving differently.
but I'll get the pump installed an have it checked out at that Cummins shop.
Damn I've got to find that posting. VBG