Small block differences per application

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EvanS

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Hi, I am looking to replace the /6 in my valiant with a small block V8, and I really haven't decided to go one way or the other, but I think I want to buy something that is complete and running , then rebuild it. This is going to be more of a budget build but want it to be reliable.

With that said, I want to buy a small block 318/340/360, and I have seen engines out there that come from RV's and trucks that are either 318 w 727 or 360 w 727.

So, what is the difference in these engines when built for an RV or truck vs a car?

Please pardon my ignorance, I'm a GM convert and trying to stay away from putting an LS motor in my mopar.
 
On the cheap find a 318 and a attached 904. If you want a hot rod, find a 360 and you can still use a small block 904. The 727's arebigger, heavier, and don't fit the trans humps of the ealy A bodies well. You will still need exhaust, mounts,driveshaft, possibly rear end and the like to complete the transformation.
 
Truck engines have a different oil pan than cars. Of course, the different pan would have a different pickup tube
 
Get a 5.9 Magnum. Find an LKQ in your area. They offer good used engines with a warranty at very reasonable prices. Add a four barrel intake, carburetor and headers and you're there. No need to rebuild, unless you just like wasting money.
 
Get a 5.9 Magnum. Find an LKQ in your area. They offer good used engines with a warranty at very reasonable prices. Add a four barrel intake, carburetor and headers and you're there. No need to rebuild, unless you just like wasting money.


I don't know about going too new. I think i like the idea of keeping it closer in age to the car. BTW its a 68 valiant signet.

On the cheap find a 318 and a attached 904. If you want a hot rod, find a 360 and you can still use a small block 904. The 727's arebigger, heavier, and don't fit the trans humps of the ealy A bodies well. You will still need exhaust, mounts,driveshaft, possibly rear end and the like to complete the transformation.

Would a 727 work in a 68 valiant hump? Would it be hard to use my 904 with my /6 with a 318 or 360?

Truck engines have a different oil pan than cars. Of course, the different pan would have a different pickup tube

Could i just replace the oil pan/pickup to fit?
 
727 fits the 68 with no problem...the problem is 66 and earlier.

yes..oil pan and pick up can be replaced.

/6 904 do not fit the small blocks.....different bolt pattern
 
Would a 727 work in a 68 valiant hump? Would it be hard to use my 904 with my /6 with a 318 or 360?
It would probably work with a little trimming and modification. The 904's came with most all A body v8's. The slant 6 case won't bolt to a v8 block.
 
What you may want to do is search around the site for threads about /6 to V8 swaps. Use the search box to help. Buy a "How to hot rod a small block Mopar" book or the like and study up. Then you can ask a few questions and get the answers you need to do the swap right.
 
Would a 727 work in a 68 valiant hump? Would it be hard to use my 904 with my /6 with a 318 or 360?
It would probably work with a little trimming and modification. The 904's came with most all A body v8's. The slant 6 case won't bolt to a v8 block.

Nope. No trimming needed. His 68 has the same hump as the 68 340 cars. 340 car = 727. It will fit fine. ;)
 
One of the members in this forum, 4speedragtop, advertised a few 318s a while back. I would contact him. A slightly warmed over 318 would be a great engine.
 
I don't know about going too new. I think i like the idea of keeping it closer in age to the car. BTW its a 68 valiant signet
Do some more research. Rusty is right. Starting from scratch kind of a no brainer not to go with a 5.2/5.9 Magnum, Plentiful and reasonable. Better power, Better compression ratio, better flowing closed chamber heads, roller cam, and they suffer significantly less wear then an LA engine with similar mileage. Installed they look nearly identical and no worries of wiping out the cam. LKQ guarantees the engine run. With a cam and 4bbl can make some respectable power. Or source an older LA 360 with an overly optimistic 8.5:1 compression and start throwing money at it. If you end up in someones backyard don't buy anything you can't hear run and holds water. Now way to tell if it's been over heated, cracked, froze what have you.
 
I'm a GM convert and trying to stay away from putting an LS motor in my mopar.

Please don't hold us hostage like that. We'll do anything to help. The difference between a truck and a car engine is slight. Probably just the cam. The heads may be different but probably not. If I had to do it all over again I'd avoid the 727 for any number of reasons. They're heavier, it takes a little more to turn them and finding a junk yard drive shaft for an 904 will be a lot easier.
 
Please don't hold us hostage like that. We'll do anything to help. The difference between a truck and a car engine is slight. Probably just the cam. The heads may be different but probably not. If I had to do it all over again I'd avoid the 727 for any number of reasons. They're heavier, it takes a little more to turn them and finding a junk yard drive shaft for an 904 will be a lot easier.
This and a basic (See post 12,for explained ,a 318/"5.2 Magnum would be a sweet swap here) look at late model Magnums,make sense.FWIW: LKQ ,has a main office in Sacramento. I have bought, and sold...their parts. I actually like a 5.2 Magnum,with a 904 here.Unless you are doing heavy hot rod work. Just an opine.
 
[QUOTE="EvanS, post: 1971842809,
With that said, I want to buy a small block 318/340/360, and I have seen engines out there that come from RV's and trucks that are either 318 w 727 or 360 w 727.
So, what is the difference in these engines when built for an RV or truck.[/QUOTE]

Besides the oil pan and pick up the exhaust manifolds are different, they use a bigger flywheel with the manual transmissions, the 727 that are used are heavy duty. The intake manifolds usually have an EGR block off plate on the four barrel manifolds used on the 360 s. Usually the heads and short blocks are the same as used in the cars until you get into the industrial motors which are usually Big Blocks. The early 318 used in the trucks had the forged steel crankshaft that everybody wanted at one time.
If you can find a E58 360 motor like used in the little red express that is a car engine that was used for cop cars.

Don't forget you'll have to get the aftermarket engine mounts or else change the K member if you were running a slant 6.
 
you'll never know it was a newer engine looking at it in the car.


Especially if you bolt on a pair of old Mickey Thompson valve covers or a nice pair of old originals. Then put on a dual snorkel air cleaner nobody will know the difference.
 
you'll never know it was a newer engine looking at it in the car.

Put the Mickey Thompson's on it an the snorkel nobody will know the difference and you tell people hey I've a roller cam in this motor, Plusl it runs like a bat out of hell.
 
By chance. Do you have a picture of your engine for us to see.
Later today,maybe. I reused the stock ten bolt Magnum v.c. gaskets,sealed the unboltable holes up ,with Permatex Ultra Grey.Let it dry,overnight...no leaks...
 
Hi, I am looking to replace the /6 in my valiant with a small block V8, and I really haven't decided to go one way or the other, but I think I want to buy something that is complete and running , then rebuild it. This is going to be more of a budget build but want it to be reliable.

With that said, I want to buy a small block 318/340/360, and I have seen engines out there that come from RV's and trucks that are either 318 w 727 or 360 w 727.

So, what is the difference in these engines when built for an RV or truck vs a car?

Please pardon my ignorance, I'm a GM convert and trying to stay away from putting an LS motor in my mopar.

Excuse me while I get my "AJ" on.

This is generally a common swap. There are a few things (caveats) you'll need to know about.

Generally speaking, exhaust manifolds and oil sump locations, there all the same. Except trucks. A 318 is a 318 is a 318 in no matter what it came in. There are special packages on some engines that have upgraded items that IMO ain't worth it because of age and/or material used.

The slant 6, small block and big block have there own transmission bolt patterns. That means that you need the matching transmission to what ever block your using.

All the cars (for the most part, not every case) use a K frame designed for that engine. So your A body car w/a /6 has just that K frame in it.

In the old days and sometimes still today, a K frame swap was/is done. This is a chit ton of work. An easier way is the Schumacher Creative Services for a kit. I have used them several times. Easy to follow instructions with minimal tools needed. Perhaps a drill and proper sized bits and a cut off wheel to trim some metal.

Another PIA thing about the Mopar's that may or may not be on other makes in the transmissions mention above, is one more thing. The 904 and 727 have different lengths to them. To keep things on the K.I.S.S level, stay with the same trans you have behind the /6 now, just the small block version.
FWIW, the 904 is lighter and uses less power to operate.

Again as above with rear ends, the mopar camp uses several rear ends sizes that are also wide and varied in width.
The 7-1/4 is most likely behind the /6. It should be considered weak for moderate V8 use.
The 8-1/4 is a very good (& highly underrated unit) that will be very good for most street strip duties.
The 8-3/4 (like the Ford 9) is a good strong rear and also a good bit more expensive. All of these rear ends have a different lengeth as well as there width.

In short, save the driveshaft to be cut down.

Engine wise, since your a ex-GM guy you can be look at the MoPar engines like this;

318, cheap, sometimes free. Very similar to a 327. BxS = 3.91-3.31
340, similar to the 350, expensive due to low numbers and legendary performance. BxS = 4.04 x 3.31
360, also similar to the 350 but with more stroke. The mopar crowd was slow to look at this engine for any other than people move due to low compression and mostly 2bbl. carbs. Known as "A Dig motor" ,the mopar crowd is finally starting to wake up to these much cheaper and plentiful power plants. BxS = 4.00 x 3.58
The 360 is externally balanced.

Magnum series engines offer better heads and are normally found cheap & in excellent condition. Due to the FI package. Edelbrock offers a RPM carb intake. MoPar used to have offered a pair of intakes. 1- an aluminum 340 copy and a single plane race intake.

IMO, go with a 360 Magnum engine, rpm intake, 650 carb & small upgraded cam. You can install the older valve covers. No problem.

(Edit, spelling & grammar)
 
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One of the members in this forum, 4speedragtop, advertised a few 318s a while back. I would contact him. A slightly warmed over 318 would be a great engine.

4spdragtop is in Canada, quite a far stretch to go from California...

Hell, I have a running 318 sitting on the side of my garage for a year and a half, but I'm kinda far for him also...
 
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