[Brian_RO]

here's a run down, i found a 1991 dakota short bed 2 wheel drive that i'm thinking about playing with street/strip. i just don't know if i should keep the pcm with the OD trans or old school this thing.

i know the rear end will need to go so what interchanges with these year dakotas?

i think i read you can change the rotors to an early dakota 5 bolt rims instead of the 1991 factory 6 bolt rims. but what is the pattern size on that early 5 bolt rotors?

what about the stock trans, is there a high stall convertor around 3k rpm and will it hold roughly 650 hp?

do they make a fuel injected intake to fit W2 heads?


here's the specs on the engine.

"X" block engine, block casting # is 4104230-318-6 casting date is 5-7-79 it is a 4 bolt main block, bore is 4.071.

Bill Miller aluminum rods and Bill Miller forged pistons with 12.5-1 compression with total seal rings.

Chrysler forged radiused billet 3.51 stroke crank with 8 bolt flange.

oil gallery sleeved for roller cam.

Engle solid Roller cam int. lift is .660 ex. lift is .671 duration @.050 int. is 278 and ex. is 287 with 108 centerline.

new-W2 cast iron heads ported & polished and flowed.

Edelbrock Victor jr. intake that has also been ported & polished.

intake valves are 2.08 and exhaust valves are 1.60 and they are the long stainless type.

10* titaniam retainers and 10* locks.

Norris stainless roller rockers 1.6 ratio steel rocker shafts stands and harden rocker shafts.

Crane 3/8" special length heat treated heavy wall pushrods.

 

[hemichuck]

The bolt circle on the 5 lug Dakotas is 4 1/2 inches which fits Mopars fords and amc's.I have installed a 8 3/4 out of a 1973 Roadrunner in my 92 Dakota and the width is almost identical,just had to weld on the shock mounts.Some of the C bodies like the Newports and New Yorkers had this same rear.You might have to move the spring perches.If you go to the 8 3/4 be sure and grab the 11 by 2.5 backing plates and drums,they really help your braking on the far end of the track.You want to keep the pcm even if its carbuerated because your voltage regulator is built into it.I always wire a Mopar electronic ignition into mine when I swap an older motor.You could find a non lockup 518 trans which uses the same stall converter as a 727 but I'm not sure how much HP the overdrive unit itself can stand.Or you could just swap in an old 727,it's a bolt in deal.The fuel injected W2 intake will probably have to be a custom piece,I dont know of anybody who has one off the shelf.

 

[Brian_RO]

hemichuck, thanks for the helpfull information. this is the first for me on this type of project and to be honest i'm not 100% sure i'm going to go through with it but i wanted to ideas what i was going to be getting into.

You could find a non lockup 518 trans which uses the same stall converter as a 727

now i didn't know such a trans was out there.

what were they used in and how do you tell them apart from the lockup version and do they have the same spline count as the older 1967-1978 727's along with how much trouble would it be to work that into that 91 year truck?

if i decide to go with a less built engine combo, i have a 1973 coronet parts car that has an 8 1/4 rear end. if the axles where the same length could they be used in that 1991 housing?

The fuel injected W2 intake will probably have to be a custom piece,I dont know of anybody who has one off the shelf.

i was afraid that would be a problem with trying to use the fuel injection so i was sorta figuring on that one.

 

[Dakotah18]

I'd love to see this project when it's finished, sounds like it will be one hell of a truck!

 

[hemichuck]

They used the non lock up 518 in a lot of the heavier duty vehicles like one ton vans and trucks as early as 1987.The way to tell when they are out of the truck is to look at the front of the input shaft and the lock ups will have the front inch or so machined down to fit in a bushing where the non lock ups are splined all the way to the end.If they are still in the vehicle you can look at the option tag under the hood and see if it specifies lockup or non lockup.I think there is an extra wire also but I will have to verify that.The spline count is the same as the 727. I am pretty sure if you pull the axles from the Coronet and set them next to your Dakota axle they will be the identical length. Keep in touch, my e-mail is [email protected] if you need to get in touch. I dont check the forums everyday,just when I have some time to spare.

 

[Brian_RO]

hemichuck thanks for taking the time to walk me through all of this and for your email address.

i'm lost after 1973 so i'm really old school.

let me pick your brain alittle more.

since i'm going to have a problem finding a fuel injected intake for those W2 heads and having to hunt down extra parts i'm starting to consider going with another engine i have sitting back which should work with just about everything in the truck with out doing any mods at this time.

i have a 1971 340 that is .030 over with 10.1 compression and a crane .470/270 cam.

correct me on my thinking on this but if i use that 1971 340 then i can use everything from the 318 and even convert the 340 intake to run the throttle body fuel injection and also use the stock trans and convertor for now as well.

now if i do something like that then what can i get by with on the factory pcm, meaning can i still use the stock pcm with out reprogramming it and just use an early electronic conversion distributor or will there be a problem with that idea?

is there a difference between that 1971 340 and the 1991 318 as far as the engine mount brackets or does that 1991 318 still have the engine bracket lugs on the side of the block as compared to the older LA engines?

the reason for this thinking is so i can just us the stuff i have laying around instead of investing money into this project.

i sorta threw out the idea of that "X" block when i seen just how heavy those boogers are, i can see that engine eating up alot of parts moving that weight.

 

[hemichuck]

The mopar factory pcm's dont respond well to performance applications.I havnt had any experience with the earlier(87-91)injection setups but I ran a 4 inch stroke 5.9 magnum with around 518 lift hydraulic roller on a stock 1995 5.9 van computor.We had to do a little tweaking on some of the sensors but it ran. There are a ton of aftermarket FI setups that would be better fit for your truck. Or you could just stick a carb on it until you find a FI system that you like!

 

[Brian_RO]

i looked at the truck and i noticed the engine brackets are different then the older LA engines.

did you have to build your own mounts or just extend the factory ones toward the front of the engine for the older LA?

do you know of anyone that could reprogram the stock PCM where it would work with that 1971 340 set up?

i'm thinking of building the 71 340 and using everything from the 91 318 including the 318 fuel injection setup to make it look stock on the outside, except for the heads.

 

[OLDSCOOL12]

Edelbrock makes a complete stand alone multi port system for older Dodge engines which is completely tunable through a keypad (included with the system). Good to 450 hp may be a bit pricey.

 

[Brian_RO]

Edelbrock makes a complete stand alone multi port system for older Dodge engines which is completely tunable through a keypad (included with the system). Good to 450 hp may be a bit pricey.

if it's anything like the MP unit they are a bit pricey. i want to say the MP unit is over $2k.

i'm going for a low budget build but yet i want to use as many good parts as possible.

 

[hemichuck]

Yes the mounts are different.There are a couple of places that make the mounts but they are real pricey($300-$400) My cousin and I are working on making some mounts that we can reproduce and sell in the $150 range,I think these would be very popular.The motor that I stroked was a 1993 model so it had the mounts already. If you are good at wiring and have an indepth understanding of injection setups you could go with a GM style pcm which is pretty common in junkyards and adapt your wiring to the sensors or use all the GM sensors and tthrottle body on your intake.There are a bunch of companies that will flash the GM computors for other uses.The cheapest and easiest solution if you want a throttle body injection might be a Holley Pro-Jection 2bbl which is reasonable and can be found at swap meets used pretty cheap sometimes.

 

[B-300]

The 2bbl projection unit will only feed about 320HP due to injector size. Also the older injectors are hard to find if needed.
I put a 700cfm 4bbl comander 950 on my van because in the longer term I could use the same sensors and ECM to convert to MPI, reusing the throttle body as an air valve to save money... You would need a larger unit to support 650HP.

 

[03DakStampede]

the 1991 dakotas with the 318 are A500 trans based on the A904. you can build them to hold power. I have my A500 in my 91 built for racing by a performance shop in Charlotte, MI called JPT and absolutly love it. As for the computer on this truck deffinalty dump it it is a TBI system which really SUCKS!!! not much if anything you can do to it. If you have the 8.25in rear i dont see why you wouldnt be ok with a 400hp mill but if you can get a 8.75in from an 70-73 E-body you would be even better off. If you run the A500 trans let me know i can dig thgough the wiring so you can still keep the od and lockup converter if memory serves me correctly you dont need to keep the computer for the od or the lockup. I also think that the 91's were the lightest year built with the v8 mine with me and a 1/4 tank and a fiberglass topper on it weighed in at 3900lbs and im not no stick (230) and i know the topper weighed at least 100-150lbs. I have seen some of the pro stock elim guys coming in at 3200lbs with the interior but no insulation etc. you have a great platform for a fun truck. Also its not hard to wire in a external voltage regulator i did this as a temporary repair when the on in the computer went bad. its wired the same as one of the old challengers or any other care before computers. I origanally wanted to do the same thing but build a 408 stroker for it. would have been real fun but Life happens. good luck and keep us updated

 

[03DakStampede]

One more thing if you are wanting to use a 318 then just use the block thats in the truck its not a magnum so all the internal parts/heads from any of the old LA engines will work. Stroke IT!!!!! 390 Stroker!!!!! SMR also builds these transmissions they do both the A500 and A518

 

[B-300]

Somewhere out there (on the web) is a place that builds HP transmissions, using torrington thrust bearings. I came across it about a year ago and it was something like "Rollerised 518 transmissions"... I didn't bookmark it since it was for racing.

 

[1baddak]

i did this swap back in 92 in my shelby dakota. put a 340 in and used the stock 318 tb . it ran pretty good but not to impressive. when i rebuilt it i changed over to a edelbrock perf. intake and a fastman 360 tb bored out to a 55 1/2 mm . this worked out good for me.iam running a stroked 340 and this worked for me. I tried a used holley kit and didnt like it.

 

[Brian_RO]

thanks everyone for the great information.

03DakStampede= One more thing if you are wanting to use a 318 then just use the block thats in the truck its not a magnum so all the internal parts/heads from any of the old LA engines will work. Stroke IT!!!!! 390 Stroker!!!!! SMR also builds these transmissions they do both the A500 and A518

03DakStampede, i had actually thought about just using the 318 that's in it but i have that 1971 340 just sitting in the corner of the garage and it's ready to go and only needs a set of bearings and gaskets, so it would be cheaper for me to go with the 340 instead of having the 318 sent to the machine shop and buying pistons and such.

1baddak= i did this swap back in 92 in my shelby dakota. put a 340 in and used the stock 318 tb . it ran pretty good but not to impressive. when i rebuilt it i changed over to a edelbrock perf. intake and a fastman 360 tb bored out to a 55 1/2 mm . this worked out good for me.iam running a stroked 340 and this worked for me. I tried a used holley kit and didnt like it.

1baddak, can you give me an idea what you had to do to run a PCM and that EFI system and how much of it was the stock pieces?

i managed to find an e-body 8 3/4 rear end, which the only reason i wanted it is for easier gear changes so i can take full advantage of different gears to see how all of this combo is going to work togeather.

as far as hp the 1971 340 should be in the neighborhood of 350-360 hp which the specs on it are .030 over with 10.1 compression with stock 1.88 intake valves and 1.60 exhaust, the cam is .455 lift and 270 advertised duration. so it isn't anything like the "X" block W2 engine i posted in the first part of the thread.

i figured the trans was very simular to the 904 trans and i have seen some of them take some pretty big hp with the right kit in them.

 

[03DakStampede]

http://engine-swaps.com/

engine mounts for the 340.

 

[Brian_RO]

http://engine-swaps.com/

engine mounts for the 340.

03DakStampede, thanks for that link. i was looking through it and noticed that the swap kits are for an original 4 cylinder or 6 cylinder truck to small block or big block V8.

it dosen't mention anything about going from a original 318 engine truck to the LA style 318/340/360 engines. :huh:


Now Available!
'87-96 Dakota 2WD 4-banger and V6 to small block and big block conversion kits are now available for 273/318, 340/360 and B/RB engines.


The kits feature two perches, left and right brackets with insulators, mounting bolts and instructions. This installation requires no welding and is a direct bolt-on using existing holes.
Tech Tips for the Dakota swap.
$385+$26 S&H.

Add to your shopping cart (4 Cylinder to B/RB)
Add to your shopping cart (4-Cylinder to 340/360)
Add to your shopping cart (4-Cylinder to 273/318)

Add to your shopping cart (V6 to B/RB)
Add to your shopping cart (V6 to 340/360)
Add to your shopping cart (V6 to 273/318)

 

[03DakStampede]

give em a call and check. i dont see why it wouldnt work the mounting position on the frame is the same for the 4,6,&8 t think its just changing them from a pad mount on the truck to a tab mount like the 340