confirmation ? Dakota fuel injection on a 318 ?

marko

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got 2 questions here about using late 90s Dakota fuel injection on a 70s 318 and on an 81 Imperial......

a friend had asked me about using a 98 Dakota fuel injection set up on a 72 dodge 318, i didnt know enough to answer him.

and then ive just been offered an 81 imperial that hasnt been started in 10 years - its still fuel injected.
i will be very surprised if we get it running.
ive had 2-3 carb converted 81 imps but never a fuel injected 1.

so is the dakota set up a viable thing to do on either of these cars ?
1 person has told me yes but he has never done it of course.....

just trying to get our ducks in a row in case i accept the offer of the imperial and my buddy tries to do the 72

tx

mark
 
ONLY IF the complete Magnum EFI system is transplanted into the 318 vehicle. Would be better to use an Edelbrock 4bbl intake and one of the self-learning TBI EFI systems, I suspect, but that might be more money (initially) to be spent.

The Magnum EFI might yield a fatter torque curve (lower and middle rpm), but it was the head improvements which got the power increase at the top rpms, as I recall.

On some years, Dodge did use a Holley 2bbl TBI unit on the pickups, as I recall. But that would still need the support mechanisms to run it, from a donor vehicle.

An AVS2 and matching 4bbl intake might be a better deal, to me, than using an OEM EFI unit. All things considered.

As for the Imperial, check the recent threads on the Imperial's OEM EFI system in here.

Just some thoughts,
CBODY67
 
As noted by CBODY67, you will need the ECU and all of the supporting sensors and wiring harness. Next question would be if the '95 system is still functional, a rebuilt ECU starts at over $200, so the conversion could turn into a money pit pretty quickly. The Holley Sniper EFI 2300 2BBL system would be another option if you desire to have an injected system. It is self tuning so the setup is not usually difficult. Otherwise you will be time and money ahead to convert to a carb of your choice.

Dave
 
TBI, maybe? TPI, no? What are you gonna use for the intake manifold? Magnum manifolds have the bolts run differently than earlier LA engines. Without the factory intake, where are you going to put the factory sensors?

I'd go for something like a Sniper kit before going thru the effort to swap over a factory system. Too much effort to make it work with minimal improvement. And since the modern Hemi has come out, the aftermarket has all but forgotten about the 3.9, 5.2, 5.9 Magnums. And don't be fooled thinking stock parts are easier to source. My daily is a '93 Dakota, GREAT little truck, but I can tell you right now electrical components will be its downfall, not overall mileage. Things are getting hard to find. Mine needed an IAC (Idle Air Control Valve) last year. The ones available from the parts houses would NOT play well with the factory computer. Had to hunt for a month for a factory one finally finding one on ebay. Computers are getting to be a 'hunt for' deal too.

After the issue with the IAC on mine, I wonder how well ANY aftermarket component will work with the stock computer.
 
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got 2 questions here about using late 90s Dakota fuel injection on a 70s 318 and on an 81 Imperial......

a friend had asked me about using a 98 Dakota fuel injection set up on a 72 dodge 318, i didnt know enough to answer him.

and then ive just been offered an 81 imperial that hasnt been started in 10 years - its still fuel injected.
i will be very surprised if we get it running.
ive had 2-3 carb converted 81 imps but never a fuel injected 1.

so is the dakota set up a viable thing to do on either of these cars ?
1 person has told me yes but he has never done it of course.....

just trying to get our ducks in a row in case i accept the offer of the imperial and my buddy tries to do the 72

tx

mark
The 90's injected 318's were Magnum engines and not LA Teens. The heads and intakes were different between the two and without major modifaciin, they will not interchange.
 
You would have to switch the heads also, definite hassel, just to end up with a crap intake and a overly complicated fuel and ignition system. The Imperial would be better as a 2 bbl fuel injection system. I'm not sure what you will lose on/in dash function. Or just put a carb and normal distributor on it.
Wish I could come across a '81 Imperial for cheap.
 
You would have to switch the heads also, definite hassel, just to end up with a crap intake and a overly complicated fuel and ignition system. The Imperial would be better as a 2 bbl fuel injection system. I'm not sure what you will lose on/in dash function. Or just put a carb and normal distributor on it.
Wish I could come across a '81 Imperial for cheap.
And the Magnum rockers oil through the pushrods so you have to replace the lifters and pushrods.
 
thanks everyone for the advice, i was skeptical of what i had been told about the dakota set up being an easy swap over.
i will pass that on to my friend and if i accept the free imperial i think a carb conversion will be in order

cheers
mark
 
If the Imperial's existing system hasn't been ruined by the methanol in the fuel, I'd give it a shot to try to get it running. The FSM has some good diagnostics on checking over the system using a standard meter. A friend of mine bought a dead one years ago and was able to get it running again with minimal investment.

Jeff
 
with the imp i will try and get it running, its been pointed out to me that since it was used til about 10 years ago it might have alot of the gremlins solved..... we shall see. kevin mccabe has advised me that an 88 to 91 dodge ram setup will work on the imp.
my friend can make up his mind what he wants to do with his project.
thanks all
 
with the imp i will try and get it running, its been pointed out to me that since it was used til about 10 years ago it might have alot of the gremlins solved..... we shall see. kevin mccabe has advised me that an 88 to 91 dodge ram setup will work on the imp.
my friend can make up his mind what he wants to do with his project.
thanks all
If you try the 88-91 Ram truck TBI, I would try to find a parts truck with everything you need.
 
Years ago, when the Magnum heads were the new 'hot ticket', there were references to a drilling-jig tool that would allow you to drill LA heads to the vertical orientation of the Magnum bolts, and vice versa. Hughes engines also sold heads with both patterns, and/or could drill yours for a fee.

Hughes also makes a nice 'airgap' upgrade intake, but it is pricey nowadays.

The Magnum engine has a number of advantages over the LA, so a whole engine swap would be more beneficial while avoiding the intake hurdle. But if doing it on a budget, the OEM stuff on an LA would still be an improvement.

Don't forget that you need to upgrade the fuel system to feed it. Some folks say an in-tank pump is mandatory, but I've read testimony from folks that it isn't 100% required.
 
When TBI came out on GM light-duty trucks in '87, we went through trying to find adequate fuel pumos for the saddle tanks some owners had. NO dice, except for the Walbro inline pump that would hit the marks for fuel pressure and volume. Not even the biggest/baddest Holley race elec fuel pump would work . . . as many tried to use it. So it was the Walbro pump which we had to get from a truck conversion vendor, at the time. On the GM TBI units, it took 53psi min pressure for the injectors to work. Less than that, just cranking happened.

Seems like somebody now makes a 4bbl intake (other than a race-oriented one from Mopar Perf) for the Magnum heads? IF SO, the Holley Sniper self-learning EFI would be the deal to use. Along with a new air cleaner unit. Let it also control the ignition activities, too.

At least when you take the air cleaner top off with the Holley Sniper unit, the engine doesn't die. As the OEM Imperial EFI engines did.

Enjoy!
CBODY67
 
Yeah, saw many discussions where that old Holley 'blue pump' caused many a novice's EFI system to not work.

Do you have a typo in the 53 psi?
IIRC the GM TBIs use around 15 psi, and the later-model 454 TBI used injectors from the 4.3 engines but ran them at 30 psi to get required flow.

From my memory, most MPFI injectors were rated at 43 psi, with 58psi becoming a more common rating point somewhere in the 2000s?
 
Yeah, saw many discussions where that old Holley 'blue pump' caused many a novice's EFI system to not work.

Do you have a typo in the 53 psi?
IIRC the GM TBIs use around 15 psi, and the later-model 454 TBI used injectors from the 4.3 engines but ran them at 30 psi to get required flow.

From my memory, most MPFI injectors were rated at 43 psi, with 58psi becoming a more common rating point somewhere in the 2000s?
I thought the same thing, early GM truck TBI was 9-13 psi, around 92 it was 13-15. The only ones I have seen higher were some of the Medium duty trucks with the later TBI, they had high 50's to 60 psi. Most multi port systems were 30 psi regulated, modern systems are around 45-60 psi
 
The Magnum engine has a number of advantages over the LA

Define advantage.

My ex drove a black Durango for a few years, blown engine, blown transmissions, a wheel fell off on a trip with my kid sleeping in the back seat, etc, etc, lemon from the word go.
 
Define advantage.

My ex drove a black Durango for a few years, blown engine, blown transmissions, a wheel fell off on a trip with my kid sleeping in the back seat, etc, etc, lemon from the word go.
Any particular vehicle can have its problems, and having an LA is no insurance against a wheel coming off.
I'm merely talking about putting Magnum EFI on an LA, that it isn't as 'good' as an entire Magnum engine would be.

I used to know this list by heart, but here is foggy memory. Many of these items are to reduce friction and increase efficiency, which give more power and more mpg.

I believe the reciprocating assy is lighter, I'm pretty sure the rods are narrower.
I think the rings are narrower - reduced friction.
Narrower valve stems that allow more flow.
Cylinder heads have significantly superior airflow and combustion efficiency, from the ports to the shape of the chambers. Yes, the Magnum heads are known to crack between the valve seats, but it is also known that the engines still run that way with apparently no known symptoms to the driver. The TBI-era LA heads were a pre-cursor to Magnums.
Magnum has a roller cam (less friction), although some late LAs did also.
Obviously, the port-EFI and ECU timing control gives better MPG and drivability.
Magnums also have higher CR than most any 318 (except for 1960s).
Exhaust manifolds that are nearly on-par with the best 340 manifolds (Magnum manifolds can bolt onto LA heads, though)

5.2 Magnums were rated at 220-230 hp depending on year, roughly a 50hp increase over the highest 175hp rating of the 318-4 copcar engines. 60s-70s 318s aren't anywhere close to compare.

A 5.2 or 5.9 Magnum is a main piece to turn an 81-83 Imperial into the equivalent of a Lincoln Mark VII LSC. Having owned 2 LSCs, and tweaking them a bit, they are a fabulous driver's machine.
 
5.2 Magnums were rated at 220-230 hp depending on year, roughly a 50hp increase over the highest 175hp rating of the 318-4 copcar engines. 60s-70s 318s aren't anywhere close to compare.

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