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Author Topic: Fuel Injection?  (Read 12547 times)

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Offline ScreamingEagle82

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Fuel Injection?
« on: February 19, 2012, 02:54:45 PM »
So I am a new owner of an 87 Sedan and I was wondering, if I wanted to convert to a fuel injection system, where would I start? What I mean is, does anyone have any idea where I could find the system to use. It's the in-line 6, and currently has a carb. Would it be difficult to do this conversion? Has anyone done this before? Any and all advice would be welcome and appreciated. Thanks.
Tom K.
'87 Sedan DD/Work in Progress

Offline kajsdf

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Re: Fuel Injection?
« Reply #1 on: February 19, 2012, 03:20:52 PM »
i am not 100% on it but i know it involves pulling the intake, fuel rail and computer from an early-mid 90s donor jeep cherokee or wrangler. there is a write up contained in the 4.0 head swap article in the eaglepedia. personally i feel the motorcraft carb swap is the easiest option to improve general driveability and fuel economy.

there is a thread on some other jeep forum that goes into a lot of detail, but it too is a 4.0 head swap article
1985 eagle wagon limited
now more limited...
2150 swap...tf727/np229 swap...258 megabuild in the works...

Offline captspillane

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Re: Fuel Injection?
« Reply #2 on: February 19, 2012, 03:30:12 PM »
All the information is here if you start cruising through the threads. The cheapest and simplest way to make your Eagle run well is Gronk's Motorcraft 2150 Carb conversion. Then there is the Howell TBI (Throttle Body Fuel Injection) kit. That is fairly simple but it costs $1200 dollars. Then there is the Jeep Cherokee version that is called MPI "Multi-port Fuel Injection." That is available in a kit for about 2500 dollars. It can be built from junkyard parts for considerably less.

I suggest reading through these two links.

http://forums.amceaglenest.com/index.php?topic=37553.msg306794#msg306794

http://www.amceaglenest.com/images/PDFS/Joshs%204.0%20Walkthrough.pdf
Currently Inspected and Insured as of Jan 2013:
-1985 Eagle Station Wagon 258 T5 Stickshift
-1980 Eagle Station Wagon 258 Auto Fuel-injected with GM TBI

Minor Repairs Underway:
-1982 Eagle SX4 258 T5
-1981 Kammback 2.5L Iron Duke T5

Restoration Efforts Near Completion:
-1982 SX4- 401 NV3550
-1983 SX4- 4.5 MPI NSG370 (6 Speed)

Restoration Efforts Underway:
-1985 SW- 4.0 MPI AX15
-1982 SX4- 4.0 AW4
-1981 SX4- SD33T NV4500 (Turbodiesel 5 speed)

Future Rescue Efforts- '85 Maroon SW, '87 Limited SW, '84 Limited SW, '87 4 door Sedan, '81 2 door Sedan, '88 White SW, '77 4 door Hornet, '74 2 door Hornet, '79 Spirit AMX, '81 Kammback.

RIP- Red '81 SX4, '84 4dr Sedan, '84 SW, '81 SW, '80 Spirit, '83 SW, '83 4dr Sedan

Offline maddog

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Re: Fuel Injection?
« Reply #3 on: February 19, 2012, 07:57:42 PM »
if i remember right that is brownbear's old Eagle which already has gronk's kit on it so the only thing he can do to get better mpg and power is to go fuel injection.
1998 CHEVY S10 (DAILY DRIVER/PROJECT) INTIMIDATIN'
1980 AMC EAGLE WAGON (PROJECT) EAGLE EYES
http://forums.amceaglesden.com/index.php?topic=30758.0
1983 AMC EAGLE LIMITED WAGON-SURVIVOR (gone)
http://forums.amceaglesden.com/index.php?topic=32372.0

Offline ScreamingEagle82

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Re: Fuel Injection?
« Reply #4 on: February 19, 2012, 08:31:45 PM »
Maddog is correct. It used to be BrownBears and already has the Gronk on it. I personally feel I could get more power, or at least more responsive power from the fuel injection system. Let alone better mpg's. I figured it was going to be expensive, at least for a kit. I appreciate the links and I'll be sure to check them out. My fuel economy is terrible right now. I'm not expecting miracles though.
I know there are some purests out there, but it's already been modded, and I think making it more economic wouldn't be too blasphemous. lol.
Tom K.
'87 Sedan DD/Work in Progress

Offline kajsdf

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Re: Fuel Injection?
« Reply #5 on: February 19, 2012, 09:56:18 PM »
even a carbed 4.0 head swap would help out with efficiency and power. fairly economical...i would especially do that if you were doing the efi upgrade to maximize benefits
1985 eagle wagon limited
now more limited...
2150 swap...tf727/np229 swap...258 megabuild in the works...

Offline ScreamingEagle82

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Re: Fuel Injection?
« Reply #6 on: February 19, 2012, 10:09:01 PM »
It's kind of funny to admit this, but this is the first Carbed vehicle I've ever owned. By the time I was old enough to drive, they were unheard of. So I guess I'm kind of paranoid about keeping it carbed. I guess I just need to weigh my options and figure out which would work best for me. Thanks for the advice guys. I'll be sure to keep you posted.
Tom K.
'87 Sedan DD/Work in Progress

Offline doc65

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Re: Fuel Injection?
« Reply #7 on: February 19, 2012, 11:14:22 PM »
Young'uns :)

Offline kajsdf

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Re: Fuel Injection?
« Reply #8 on: February 20, 2012, 01:25:43 AM »
its my first carbed car too...honestly, i like it...keep it analog, no computers. frustrating at times, but overall simpler
1985 eagle wagon limited
now more limited...
2150 swap...tf727/np229 swap...258 megabuild in the works...

Offline maddog

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Re: Fuel Injection?
« Reply #9 on: February 20, 2012, 03:43:30 AM »
By the time I was old enough to drive, they were unheard of.
the same is true for me but i think carbs are better than injection as there is less to go wrong but that's just my opinion.
1998 CHEVY S10 (DAILY DRIVER/PROJECT) INTIMIDATIN'
1980 AMC EAGLE WAGON (PROJECT) EAGLE EYES
http://forums.amceaglesden.com/index.php?topic=30758.0
1983 AMC EAGLE LIMITED WAGON-SURVIVOR (gone)
http://forums.amceaglesden.com/index.php?topic=32372.0

Offline Pat

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Re: Fuel Injection?
« Reply #10 on: February 20, 2012, 09:37:36 AM »
1995 Jeep Cherokee "Bleep"



No pic here - BlackBird - My '86 AMC Eagle wagon

R.I.P Old Rusty - My '91 F150

Offline GRONK

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Re: Fuel Injection?
« Reply #11 on: February 20, 2012, 10:39:08 AM »
If this is Brownbears old eagle I can help.  I remember we had a few issues working through the install but I can definitely get you going in the right direction and make sure everything is as it should be.  I have Jeeps and eagles getting low 20's at sea level and high teens at elevation (I average 19mpg in a CJ5 running strong as can be)

My direct email is: [email protected]

Send me some good pics and info on what you currently have and I'll help make sure everything is right.
"Bucket" 1983 Limited Wagon
"Tootie" 1984 Wagon
Owner - GRONK Performance

Offline txjeeptx

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Re: Fuel Injection?
« Reply #12 on: February 20, 2012, 03:11:37 PM »
I'll assume your car has a 3-speed automatic, which would mean it has no overdrive gear in the transmission, so the engineers at AMC opted for high ratio axle gears to give the car a better highway-cruising engine speed at a sacrifice of acceleration performance getting up to highway speed. If you seldom drive long distances at highway speeds, then this trade-off that the engineers made has a large negative impact on your fuel mileage and acceleration performance.

Check your axle gear ratio to see what it is(small tag on one of the differential cover bolts will have stamped numbers, one of them is a X.XX format, which is the axle ratio). AMC liked to put gears that are way too high into the axles to try to get better fuel economy at highway speeds, but this sacrifices city driving fuel economy, since it hurts acceleration performance. If your car has high axle gears(2.53 or 2.73 were common for automatic trans cars), but is rarely driven on the highway, and/or has larger tires than the stock size, then you will see more improvement in fuel economy with a gear ratio change than you will from anything else. If you really want better fuel economy, you'll benefit much more by swapping in a 5-speed manual transmission with overdrive and lower ratio axle gears to improve acceleration. Really really really want economy? Wrong kind of car - buy an import econo- :censored: -box or a bike.

Fuel injection should be swapped in to improve driveability/start-ability & to improve performance, not so much for fuel economy. If you go through the trouble of installing fuel injection without addressing the possibility of an overly high final drive ratio, you will not see any improvement in fuel economy. Tire size is a big part of final drive ratio, and oversize tires make for poor economy based on increased rolling resistance and weight, not just the increase in final drive ratio due to the increase in diameter. Want economy? Try smaller and lighter tire and wheel combos. Want to look cool with big tires? Forget about economy. You can get some of the economy lost on big tires back by swapping in lower axle gears, but this doesn't address the increased weight and rolling resistance, it only corrects the final drive ratio to put the engine back into its most efficient operating speed.

That said, fuel injection can be a huge improvement in driveability and performance-ability over a carbureted system. The 4.o HO head is a better flowing design, and, coupled with the 4.o's fuel-injection-designed cam, is the real driving force behind why the 4.o makes nearly a hundred more horses than the 4.2, not just the fact that one has fuel injection and the other has a carb. Just swapping in fuel injection without swapping in the better head and camshaft will make only a small gain in performance over the MC2100 carb, which is a great carb, vastly superior to the factory Carter.

If you want to improve performance, I'd recommend swapping in a 4.o head, and a 4.o camshaft, if you're really ambitious, but its nearly impossible to swap in a camshaft with the engine in the car. Swap in fuel injection only if you aren't capable of learning the nuances of carburetor tuning(or don't care to bother with learning the lost art of tuning), and just want to be able to turn the key every day and have a computer do the tuning for you.

One last note - usually when you start making performance a priority, economy goes out the window. Dammn the MPG, full speed ahead!
'82 Eagle SX/4 "Golden Eagle", '89 YJ 2.5L '93 MPI-converted rock-crawler, '79 Jeep Cherokee Golden Eagle "FSJ", 'o7 F150 Supercrew FX/4 daily driver

Offline ScreamingEagle82

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Re: Fuel Injection?
« Reply #13 on: February 22, 2012, 11:51:08 PM »
Thanks for the info TxjeepTx. I've thought about it for a few days and I think I'm going to go with the 4.0 swap and leave the carb. It seems like a workable option and since I don't plan on driving it long distances that often, it should be ok for me. I think I'm also going to check out this gear ratio issue and see what I can do from there. It's like spiderman says, with great power comes a great lack of economy.....or something like that. lol. Seriously though, thanks for your suggestions.
Tom K.
'87 Sedan DD/Work in Progress

Offline EagleW

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Re: Fuel Injection?
« Reply #14 on: January 01, 2019, 06:02:47 PM »
I have a factory 1983 Eagle Wagon with a I6 258.  The carb is also factory.  I am wondering what gains in HP or reliability I would see if I did the following and what what it would take to do as far as electrical: (using parts from a 4.0 jeep engine)

option A:  Swap the head and cam shaft. 

option B: Swap the manifold, injectors, and throttle body.

Option C: all of the above.
 
also if it's possible and what years I could scavenge from?



Offline rmick

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Re: Fuel Injection?
« Reply #15 on: January 01, 2019, 09:02:18 PM »
The head and cam swap should get you close to 55 hp increase. May be able to get more with different cam.

Not sure how much the fuel injection will get you but it defiantly improves drivability. I have a Gremlin I have done a complete 4.0 swap and my Eagle I have done the head and added fuel injection kit made from a 4.2 chevy throttle body set up.
72 Javelin AMX
72 Javelin SST
72 Gremlin with 4.0
81 SX 4

Offline EagleW

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Re: Fuel Injection?
« Reply #16 on: January 01, 2019, 10:50:13 PM »
thanks for the info.  It is very helpful.  I was glad to find a forum that was dedicated to AMCs.   

Offline vangremlin

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Re: Fuel Injection?
« Reply #17 on: January 02, 2019, 08:55:35 AM »
I've done the head, cam, and fuel injection to my Kammback.  Very noticeable improvement after the cam and head swap, then several years later I added the GM TBI, which to me greatly improved the acceleration and driveability.  Not sure the acceleration improvements would have been possible without the cam and head swap.  The throttle body kit came from Performance Fuel Injection Systems, they have their own web site and also sell on eBay.  It's a nice kit.

Good luck!
1981 Kammback 258 - "Pepe"
1980 Coupe 258 - "Ginger
1972 Gremlin X 304
1978 Gremlin 4 cyl 121 - sold
1964 TBird 390 - sold

 

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