possible engine swap

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MercuryMac

Builder Junky!
Joined
Jan 18, 2013
Messages
4,919
Location
Northern Alberta, Canada.
A friend of mine wants to swap an LA 318 V8 onto the bellhousing of a 3.9 V6, with a Newprocess 5 speed. The 3.9 is of the same family as the 318 so I think it will work, but I have not tried this swap. Have any of you done this Chrysler engine swap? He is putting a '39 Fargo truck on a 1990 Dakota and wants to swap in the 318 for V8 coolness.
 
I swapped the auto trans that was behind a 318 into my 87 Dodge Dakota with the 3.9 v6. Later swapped in a 360 and bolted to the same transmission. Everything fit just fine. Had to fab some motor mounts and hammer some clearance for the distributor into the firewall and make an exhaust system. Other than that the 360 was a bolt in.
 
Thanks, sc, that tells me the bolt pattern is the same. Good. I was hoping the flywheel off the 3.9 would bolt onto the 318 and that the ring gear would reach out to the starter.
I guessed we'd have to make motor mounts, exhaust, pilot bearing hole, but it was the bell bolt pattern and the flywheel that was bothering me.
Thank you.
 
guys,, a quick question please.

I would love to run a old time hemi in my coupe,

however affordability is driving me to an LA318. noting your comments above,, how does the '90 Dakota 5 speed compare to a early 90's jeep Cherokee ?

the Jeeps are plentiful here in New Zealand, not so much the Dakotas ..

thanks Crate
 
I know how you feel on running a Hemi.:cool::cool::cool:
The transmission in this 1990 Dakota is a New Process A535. Sometime in the early nineties New Process sold out to New Venture Gear, I think, but they kept making this transmission and still called it A535. I bet Jeep would use that transmission for a while too. It's looking like if you found a Jeep with that trans and a 3.9 litre or a LA318 you'd be laughin' all the way to the bank. Good luck, but do some more information searching and don't completely trust me.
 
Hi again, Crate. I did some more digging around and didn't find that Jeep used a 3.9L motor or an A535 New Process or the renamed version NV2500. Jeep did use a 318 though with a newer heavier NV 5 speed, which would work nicely.
The pictures are #1 a baby Hemi to brag about, going in my 34 Plymouth, with an A833 bolted to the back. Most people will tell you that that can't be done. Where there's a will there's a way.
pic#2 is tips to watch out for when mixing motors and transmissions. Pilot bearing size and look to see if you have a female opening in the back of the crankshaft or flywheel centre, or do you have to make one.
pic #3 measure length of clutch shaft and depth of bell housing.
 

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Great info M Mac, thanks for your time !,,

im a wee way off yet but its very good to have something to go on , plus will give me plenty of time and having the gearbox codes for foraging - brilliant - to see what is available locally ..

Was talking to a friend at a local swap , who also suggested a late model hemi , cheaper to run (we are paying the equivalent of US $5.46 per gallon ! ) - with fuel injection yet still has the hemi look .. so options are expanding .

great lookin engine room you have there, ive been following your build thread, good to see something a little off the ordinary being built

Thanks again Crate
 
And speaking of off the ordinary, I've been thinking about you all day and I've come up with another possible Mopar entry that could be found nearby. How about a poly 318 wide block. There should be some of them around there in pickups and bigger trucks up to 400's and 500's, [I believe you call them 4 and 5 tonners]. They will have a NP435 four speed or a NP five speed, [without overdrive, though] behind them. Those Polies were make from 1956 to 1966 or 67. I'm with you on putting a Mopar in a Mopar. Good hunting.
 
M Mac,, you have given some great food for thought..
during the 80's I knew a chap who set up a tow truck business . Using upwards to 5 dodge at4 1 ton p ups.. he pulled the 225 slopers and a 245 hemi six and bolted a 318 up to the original 4 speed. just bolt and go, aside from exhaust etc.
that could be worth pursuing (!) those pick ups were quite plentiful here.

As were those big old polys, in fact a lot of guys passed them over for 318s or just swapped them for a chevy .. the impression I have from then was the polys were underpowered lumps not much good for anything. however recently a chap from the Hamb offered me this link - (which I found wow'd me) here was a seemingly untapped source of hemis. at the risk of further increasing the prices of second hand old school hemi heads.....

http://www.hotrod.com/how-to/engine/0805sr-vintage-engines/

I am aware of a what was once a good poly sitting in car tucked away for a good 20 years un started.... + numerous other mopars certainly the owner may be a good place to start..

thanks again
Al - crate
 
Crate, here's some more dreaming. Dreaming with no logic at all. I have a poly 318 that turns over and a 354 Hemi that is really seized, well sir, I've measured and sat on a five gallon pail imagineering and scheming trying to stick those Hemi valve covers on that Poly. So far I'm battin' zero.
I think the Poly might have the same bellhousing pattern as the LA 318 which is good news.

My friend stuck his LA 318 onto the bellhousing of his 3.9 and NP535. It bolted up just fine, the flywheel bolted onto the crankshaft and there was a pilot bearing the right size already in place. The starter bolts onto the bellhousing so it should still fit the ring gear on the flywheel. The trans mount is the same so fit nicely, but the motor mounts are about 4" ahead of the 3.9 mounts.
 
Mac.. ha imagineering, I like that !,, im sure if it could be done....

i'll share this with you... 3 equal parts turpentine, brake fluid and 20/40 engine oil. strip the block till all you have is block and seized pistons in place. ( No crank + a rag tied around the crank end of the con rod... at this point best to do each cylinder one at a time or it gets somewhat messy..
ok.. so pour in enough to keep the top of the piston under about 1/8" liquid, and let sit for 1/2 hr or a beer. then a piece of 2 x 3 (wood ) and FBH ( fairly big hammer - 2lb ballpein I used ).
empty the bore and anywhere between a couple light taps on to the wood, through a good couple of whacks and It should let go..

save that 354 ! :D

this worked where a local engine reco company gave up and had wrecked the bore with a flat screw driver !

I think you are right about the poly and LA 318 bellhousing, think that is what they've been doing here too.

great so other than V6 to V8 motor length for mounts this seems perfectly do-able,, possibly as im going to end up building a scratch build frame that difference may not affect me as much as firewall shape...

Thanks Crate
(Al)
 
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Thanks Crate, I'll try that.
Yes the V8--V6 swap worked out nicely.
Chrysler pistons don't stick much in cylinders, but sometimes valves can be annoying.
My 354 is stuck but I haven't even tried to free it up. I will not throw it away.
 
Attention all Mopar guys, here's some great chevy-spanking news. There's a small new company cranking out speed equipment for the 318 Polysphere motors. They are advertising aluminium dual plane four barrel intake manifolds, long headers, aluminium finned valve covers, and new core camshafts to be ground to your pleasure. I'll bet you could be the first on your block to put a Poly in your hotrod, all blinged up too. :cool::cool::cool: If you got started right away.

PolySuperPac is the place to go.

Crate this might be your ticket to heaven.
 
roger that Mr Mac,, Great find !!!

I will buying some of those finned rocker covers first , man they good !!,, just as soon as I locate a motor !!
 
The PolySuperPac is part of the ChryslerPowerMagazine operation. Check for some back issues for details on the new parts.

Word of caution on swapping 318P engines.
The pre-62 engines have the same crank flange design and bellhousing bolt pattern as the EarlyHemi. The easy way to spot these is the 8-bolt crank.
62-66 (67 in Canada) engines have the same layout as the LA engines.

Depending on what you are working with one may work easier than the other.

Stroker crank? 402 cubic inches??? Yes, but only with the post-62 block. Yes, the crank will fit the early block but you will gain a huge headache dealing with the bell bolt pattern.....don't be tempted.
 
Thanks Way, I think I remember reading something on the '62 and older poly blocks having the same bolt pattern as the Hemis. I am keeping my eye out for one bellhousing to fit on my 354 as I only have a big old truck bellhousing on it now. The bolt holes may line up but the centering dowels don't, I think.
 
If you are trying to minimize the 'special' parts the look for one of the oem bells from about 57-59, usually found on the 230-I6, that also has the v-8 block bolt pattern. They do exist.
This would allow the use of all oem parts including the flywheel and starter.
The best part of this bell is that with minimal work you can bolt-up an A-833 if that is the route your are going.
 
Good thinking, Wayf. I just got a bellhousing for a 230 I-6, but it's a tractor one so has no bolt holes in the back. I know where there are quite a few flathead six belhousings so you might have saved me much scouring the countryside. Thank you.
 
Here's a hiccup note on the LA318 to a 3.9L swap. I told you that my friend slid his 318 on there likity-split. Well, that part is true. Over the next couple of weeks while he did little side chores, it kept bugging him that it went together that easy. We measured everything we could think of [and reach] while it was all assembled. Finally we took it apart again and found that the pilot shaft had only reached the pilot bushing and was not resting in its place with 5/8ths" of mating surface touching. Maybe 1/32" was penetrating [not good enough]. He went to town and got another brass bushing machined that was longer and installed it. That fixed the problem.
 

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