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I need help to improve gas mileage...
11-17-2010 | 12:11 PM
#17
☠ CF Sheriff ☠
Joined: Nov 2009
Posts: 15,197
Likes: 17
From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
Stay away from Bosch plugs. The standard Champion Copper Plus are what the engine seems to like best. RC12LYC
11-17-2010 | 12:18 PM
#18
Member
Joined: Oct 2010
Posts: 204
Likes: 1
From: NY
Year: 2001
Model: Cherokee
Engine: 4.0L
Clean your stock injectors and dont bother upgrading. Your clogged.. Look at this.. I just spoke with http://www.mrinjector.us/ Bill.. I bought Filters and O rings for my stock units and for some used injectors Boche 784's that are on the way.. He told me for this style Intake spray pattern is not critical if not relevant at all. Thats why Jeep kept using these injectors that shoot gas like a water gun. Spray pattern is critical in OTHER applications but not on the 4 liter because, according to Bill, this style intake will put gas in a READY mode for use during driving and that gas can SIT inside the motor/ head/ cylynder until its used.. So spray patter is meaningless.. Somehting like this he told me.. Im no motor genius.. These guys have all the rebuild parts for the stock injectors. Anyway, I now have in my possession the fords stated here, I have 2 sets of stock injectors that will be refurbished to new, and I have a set of 784's that Im rebuilding with new rings, filters and caps, I will also be ordering the c4b's. When I am done I will have mileage specs on ALL 4 sets of injectors.. I will run two tanks out on each style to see what gas mileage I get.. When im done the results will be exacting.. Right now im lucky to get 15mpg with these fords Im running as stated in this thread. By the time Im done I will have spend hundreds of dollars to rebuild and buy injectors.. So much so i will begin to sell them off.. I even bought a Jewlry cleaner to clean the tips. lol.. All in the persuit of better gas mileage.. Im starting to spend so much on injectors that I wont make it up on gas..
11-17-2010 | 12:30 PM
#19
☠ CF Sheriff ☠
Joined: Nov 2009
Posts: 15,197
Likes: 17
From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
that doesn't sound right at all. Many people have have good to great improvements using the 4 hole injectors. You do NOT want gas to "sit" in the cylinder of an engine. The intake has nothing to do with the injectors on this engine since the injectors are direct injection into the cylinders rather than the intake/TB like on some vehicles.
It's simple engine/fluid mechanics that a finer "mist" of fuel will ignite more completely and easily than a stream of fuel or a drip. It results in much better combustion and power, and less fuel consumption to produce the same amount of power.
It's simple engine/fluid mechanics that a finer "mist" of fuel will ignite more completely and easily than a stream of fuel or a drip. It results in much better combustion and power, and less fuel consumption to produce the same amount of power.
11-17-2010 | 12:48 PM
#22
Member
Joined: Oct 2010
Posts: 204
Likes: 1
From: NY
Year: 2001
Model: Cherokee
Engine: 4.0L
that doesn't sound right at all. Many people have have good to great improvements using the 4 hole injectors. You do NOT want gas to "sit" in the cylinder of an engine. The intake has nothing to do with the injectors on this engine since the injectors are direct injection into the cylinders rather than the intake/TB like on some vehicles.
It's simple engine/fluid mechanics that a finer "mist" of fuel will ignite more completely and easily than a stream of fuel or a drip. It results in much better combustion and power, and less fuel consumption to produce the same amount of power.
It's simple engine/fluid mechanics that a finer "mist" of fuel will ignite more completely and easily than a stream of fuel or a drip. It results in much better combustion and power, and less fuel consumption to produce the same amount of power.
All you have to do is buy a service kit for the Siemans Deka thats in the truck STOCK from this company and your good to go.. YOUR INJECTORS ARE DIRTY! changing to 4 hole is uselss. USE YOUR BRAIN! WHY DID CHRYSLER NOT GO 4 HOLE IN 2001?? NEONS WERE USING THEM THE SAME TIME THEY WERE PRODUCING JEEPS RIGHT? WOULDN'T THEY HAVE SAVED MILLIONS USING ONE KIND OF INJECTOR FOR JEEPS, NEONS AND CARAVANS?? CHRYLSER ENGINEERS ARE MORONS?? COMON!! INSTEAD THEY USED THESE STOCK INJECTORS BY SIEMANS DEKA ALL THE WAY TO 2004.. WHY DID THEY NOT RUN THE 784'S IN JEEPS FROM 2001 TO 2004 THEN?, DID YOU EVER ASK THAT QUESTION? THEY ARE NOT GOING TO MAKE A DIFFRENCE AND ILL PROVE IT IN MY LONG TEST OF ALL 4 STYLES.. I HOPE IM WRONG SINCE IM PAYING 320 PER GALLON NOW FOR GAS HERE IN NY!! IM GOING TO SELL THE JEEP IF I CAN'T GET IT TO 18MPG.. my best hope is the c4b's to improve gas which flow less. IM wasting my time but I will get the best set for my truck.. I could be wrong and I hope that the 784's work better! I doubt it though
11-17-2010 | 01:02 PM
#23
☠ CF Sheriff ☠
Joined: Nov 2009
Posts: 15,197
Likes: 17
From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
To save money? A 4cyl 2.0L engine is more sensitive to combustion levels to produce power.
Here's why they are better, regardless of the reason jeep decided not to use them:
I am NOT saying you are wrong about them being dirty - i'm sure a lot of people do indeed see a huge improvement because they swapped their dirty injectors from clean ones. I'm saying that you will likely see a decent 2-3mpg improvement from having injectors that better atomize the fuel going into the cylinders. If you purchasing cleaned/refurbished injectors, and sending them your old injector cores anyways, why not upgrade at the same time?
Here's why they are better, regardless of the reason jeep decided not to use them:
The EV1 (pintal type) & EV1.3 4 hole injectors are inferior to the newer EV6 injectors for a number of reasons.
Pressure sensitivity Ev6 injectors can be used over a wide range of fuel rail pressures the EV1&1.3 can only be used at there nominal design pressure.
The earlier bodies are made of metal and plastic, which can leak or even brake at the join, and due to the metal are more prone to heat soak, Ev6 injectors are constructed of a single plastic casting.
Response time of the injector is quicker in the EV6 injectors than the older designs. Atomization of the fuel is also better / more complete.
Extract from bosch fuel injector pamphlet: http://www.cannell.co.uk/Bosch_Techn...linjectors.pdf
Effects of Fuel Pressure on Pintle Type Fuel Injectors.
Fuel velocity through a pintle type fuel injector [type code EV 1] can dra-
matically affect its ability to atomise fuel. The profile of the pintle used in a
fuel injector has a direct relationship to the operating pressure it is designed
to operate under. Whilst Bosch produce various fuel injectors that may flow
the same amount of fuel at a given specification, the system operating pres-
sure will influence the pintle profile. Correct pressure will result in a well
atomised spray, while insufficient pressure will result in a “hosing” effect.
Excessive pressure will result in either “hosing” or a spray angle that is too
large for the targeted area dependent on the pintle profile.
The consequence of excessive fuel pressure on a pintle type injector may
well be that as the pressure is increased the mixture values of the engine
may appear to get leaner. This is of course not the case, but the fuel being
injected is no longer atomised and is entering the cylinder as a liquid mass.
This will typically cause the Hydrocarbon [HC] values to rise due to the raw
fuel exiting the cylinder, and the Carbon Monoxide [CO] to drop due to
insufficient combustion.
Later design fuel injectors [type code EV 6] use “director plate” multi-ori-
fice technology to better atomise fuel across various operating pressures.
These injectors allow more flexibility in relation to operating pressures with-
out compromising spray efficiency or fuel atomisation.
Pressure sensitivity Ev6 injectors can be used over a wide range of fuel rail pressures the EV1&1.3 can only be used at there nominal design pressure.
The earlier bodies are made of metal and plastic, which can leak or even brake at the join, and due to the metal are more prone to heat soak, Ev6 injectors are constructed of a single plastic casting.
Response time of the injector is quicker in the EV6 injectors than the older designs. Atomization of the fuel is also better / more complete.
Extract from bosch fuel injector pamphlet: http://www.cannell.co.uk/Bosch_Techn...linjectors.pdf
Effects of Fuel Pressure on Pintle Type Fuel Injectors.
Fuel velocity through a pintle type fuel injector [type code EV 1] can dra-
matically affect its ability to atomise fuel. The profile of the pintle used in a
fuel injector has a direct relationship to the operating pressure it is designed
to operate under. Whilst Bosch produce various fuel injectors that may flow
the same amount of fuel at a given specification, the system operating pres-
sure will influence the pintle profile. Correct pressure will result in a well
atomised spray, while insufficient pressure will result in a “hosing” effect.
Excessive pressure will result in either “hosing” or a spray angle that is too
large for the targeted area dependent on the pintle profile.
The consequence of excessive fuel pressure on a pintle type injector may
well be that as the pressure is increased the mixture values of the engine
may appear to get leaner. This is of course not the case, but the fuel being
injected is no longer atomised and is entering the cylinder as a liquid mass.
This will typically cause the Hydrocarbon [HC] values to rise due to the raw
fuel exiting the cylinder, and the Carbon Monoxide [CO] to drop due to
insufficient combustion.
Later design fuel injectors [type code EV 6] use “director plate” multi-ori-
fice technology to better atomise fuel across various operating pressures.
These injectors allow more flexibility in relation to operating pressures with-
out compromising spray efficiency or fuel atomisation.
I am NOT saying you are wrong about them being dirty - i'm sure a lot of people do indeed see a huge improvement because they swapped their dirty injectors from clean ones. I'm saying that you will likely see a decent 2-3mpg improvement from having injectors that better atomize the fuel going into the cylinders. If you purchasing cleaned/refurbished injectors, and sending them your old injector cores anyways, why not upgrade at the same time?
11-17-2010 | 01:20 PM
#24
Member
Joined: Oct 2010
Posts: 204
Likes: 1
From: NY
Year: 2001
Model: Cherokee
Engine: 4.0L
To save money? A 4cyl 2.0L engine is more sensitive to combustion levels to produce power.
Here's why they are better, regardless of the reason jeep decided not to use them:
I am NOT saying you are wrong about them being dirty - i'm sure a lot of people do indeed see a huge improvement because they swapped their dirty injectors from clean ones. I'm saying that you will likely see a decent 2-3mpg improvement from having injectors that better atomize the fuel going into the cylinders. If you purchasing cleaned/refurbished injectors, and sending them your old injector cores anyways, why not upgrade at the same time?
Here's why they are better, regardless of the reason jeep decided not to use them:
I am NOT saying you are wrong about them being dirty - i'm sure a lot of people do indeed see a huge improvement because they swapped their dirty injectors from clean ones. I'm saying that you will likely see a decent 2-3mpg improvement from having injectors that better atomize the fuel going into the cylinders. If you purchasing cleaned/refurbished injectors, and sending them your old injector cores anyways, why not upgrade at the same time?
11-17-2010 | 01:40 PM
#25
CF Veteran
Joined: May 2010
Posts: 3,405
Likes: 2
From: Fort Collins, CO
Year: 1996
Engine: 4.0L HO
My brother's diesel instructor at wyotech claims he has a turbocharger running 2lbs of boost on his 4.0L XJ and gets 38mpg. I won't believe it until I see it but if he isn't bull****ting, that is pretty amazing.
11-17-2010 | 01:42 PM
#26
Junior Member
Joined: Nov 2010
Posts: 79
Likes: 0
Model: Cherokee
not to hijack but i just got a 94 with a 99 engine, would these injectors work here too? i have a long hwy treck to work but every bit helps im working on my foot problem big difference from supercharged car to lifted jeep lol
11-17-2010 | 01:44 PM
#27
Member
Joined: Oct 2010
Posts: 204
Likes: 1
From: NY
Year: 2001
Model: Cherokee
Engine: 4.0L
Wow please keep us posted.. lol.. sounds like bull.. Can you imagine! At 320 a gallon here in NY for gas and i get 15mpg.. Well lets see.. I would be saving 23mpg!!
Ill buy it if it works
11-17-2010 | 01:47 PM
#28
☠ CF Sheriff ☠
Joined: Nov 2009
Posts: 15,197
Likes: 17
From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
12-02-2014 | 05:13 PM
#29
Newbie
Joined: Dec 2014
Posts: 1
Likes: 0
Model: Cherokee
Link or part number?
I replaced every fluid from front to back, replaced the spark plugs, found optimal air presure, and installed more efficient injectors. I went from 12ish to a reported 19.5 on the highway from the on board computer. It is a 2000 Sport with 27" tires.
for injectors, do a search on "Neon Injectors", they are 4 port instead of the older 1 port and atomize the fuel better.
for injectors, do a search on "Neon Injectors", they are 4 port instead of the older 1 port and atomize the fuel better.
12-02-2014 | 05:21 PM
#30
Senior Member
Joined: Jan 2011
Posts: 842
Likes: 5
From: Escalon, Ca
Year: 1996
Model: Cherokee
Engine: 4litre
You mentioned you make 450 stops per shift? If that's true that's why your fuel milage is so bad, it probably won't improve much no matter what you do. Internal combustion engines are only effecient once the vehicle is up to speed, hence why hybrids use the electric motor from a stop and around town, and the gas engine while at hey speeds.
Not trying to **** in your Cheerios, I simply don't see it getting better.
Not trying to **** in your Cheerios, I simply don't see it getting better.
Last edited by Gary Briggs; 12-02-2014 at 05:33 PM.