swap out the slant 6

[James]

hey, so im thinking of swapping my /6 to a 318. I have a 71 valiant 225cid, and i want to put in a 318 A block poly built from 1956-67. would this still work even tho its a different era? would everthing line/match up? im thinking i may also want to get rid of the 3-spd auto(lame) and put in a 4 spd. would doing this make the task easier? is the swap worth it money-wise to performance? or should i just put that money into the 6. i just wanna shred the tread! anyone have a comment? (ps: im only 17 so its a low-budget.)
(pps: tuners and ricers suck!)

 

[IndianaDodge]

Check out a Mopar Muscle or Mopar Action Magazine you can find at any magazine stand... A company offers the motor mounts needed to install a Small block 318 into your 6 cyl car. This could make it much easier for what your looking for. Build your 318 stock with a four barrel and a set of headers maybe a mild cam! should be what your looking for! you will also need to find a 904 or 727 transmission used for a small block... I would bet your car has a 904, I would find a late model Chrysler product with a 904 used behind a small block 318! The 727 if used will require a diff drive shaft! using a 904 your small block and tranny will bolt right in with the special motor mounts you can buy!, I would buy a new set of U-joints for the drive shaft since you plan on tearing up some tires!
Some other details may be in order to make this project work! nothing serious but some small details will need to be made with equipment change such as! Engine linkage, distributor Points/Elec ign, header's/stock A-body Ex manifolds, a stronger rearend such as an A-body 8 3/4 or 9 1/4, I am not sure what years these little rearends were used, but your car could have the 7 1/4 or 8 1/4rearend which is not very strong when burning your tires, so your current rearend will work but could give you problems after a few burnouts, anytime you start building somthing to tear up tires stronger parts are needed. If your not sure of what rearend your car has, find the numbers near the front of the center housing near the drive shaft, someone on this site can help you... you could be lucky and already have something strong already. I did see an 8 3/4 in a 1970 four door A-body 6 cyl car once. the car was ordered that way or changed at dealer to be used for hauling a small boat or camper! Good luck and I hope my info can help!

 

[rumblefish360]

Ohh, this is only the 4rd time trying to post this F$%^*( response, so bear with me, heres a short version;

No one I know of makes a poly swap kit. I think the "LA" mounts would work though. IMO, skip it in favor of a "LA" because of the plentyful over the counter part selection and save money while your at it. Not to mention weight.
The swap to 4spd doesn't make it easier. Just alot of fun once you get it right.

I did this here; http://www.forabodiesonly.com/mopar/showthread.php?t=10508&page=1&pp=20 Click it and read on.

 

[dartley]

Ohh, this is only the 4rd time trying to post this F$%^*( response, so bear with me, heres a short version;

No one I know of makes a poly swap kit. I think the "LA" mounts would work though. IMO, skip it in favor of a "LA" because of the plentyful over the counter part selection and save money while your at it. Not to mention weight.
The swap to 4spd doesn't make it easier. Just alot of fun once you get it right.

I did this here; http://www.forabodiesonly.com/mopar/showthread.php?t=10508&page=1&pp=20 Click it and read on.

Yeah, if you have the old poly engine for sure (you're sure that's what it is, right?) you have a pickle of a job on your hands and unless you are really an amazingly good mechanic for 17 years of age I'd vote a definate no on that!

Check the AllPar site for details on the size and weight of the poly engine. The old Direct/Connection hotrod books don't even offer any advice on hot-rodding this engine ... while they do for the /6. Advice in general will be major hard to come up with.

On the other hand, advice for the /6 is right here ... http://www.slantsix.org/
... so, before you do anything at all ... I'd look at this site. This will be much easier on your time and budget, you'll stay with a better handling car with almost perfect front/rear weight distribution and save yourself alot of parts chasing. Not to mention that, at 17 years old, it should help keep you out of some trouble ... I was 17 once and can recall all too clearly where my head was at ;o)

If you do go with any V8 at all - that rear axle will have to go too ... so plan on that in the budget.

 

[66dartman]

If your on a budget and want to shred tread, ditch the 318 poly, go down to a salvage yard and get a 360. Rebuild it stock with a 4bbl and headers and it will be plenty for your 71. 360's are still plentiful and cheap and offer great bang for the buck.

 

[rumblefish360]

Great point and advice.

Heres a thought....Low mileage Magnum 360 engine with these parts swapped out/added.

single plane intake from MoPar
750 cfm carb
Big tube headers
Create engine cam and springs
Add LA water pump and timing cover with fuel pump ecentric and fuel pump for carb.

Now, you just did a copy of the 360/380 HP create engine for cheap. Just make sure the engine is a low mileage unit.

 

[SlotCarWon]

To answer your questions:

Is it worth it? Well no, it's not. The 318 poly is just a big engine and probably wouldn't fit in your car without some major cutting. It would be lot of work and probalby too much cash just to have something unique but not that impressive perf-wise. Basically there's a reson nobody has really done this.

I think it would be a lot simpler to look for a V-8 A-body, with some simple upgares like a four barrel carb and intake plus dual exhaust you'll have a great running car for a lot less money and aggrevation.

At 17 I know cars can be a lot of fun but you need to make sure your drivng record stays clean. One or two innocent incidents and you'll be paying a ton for insurance, for forever! Instead you should go to the closest track (might need to be 18 to race) and check out what it's like to run the 1/4 mile. You can shred some tires and be safe.

 

[19duster74]

Ohh, this is only the 4rd time trying to post this F$%^*( response, so bear with me, heres a short version;

No one I know of makes a poly swap kit. I think the "LA" mounts would work though. IMO, skip it in favor of a "LA" because of the plentyful over the counter part selection and save money while your at it. Not to mention weight.
The swap to 4spd doesn't make it easier. Just alot of fun once you get it right.

I did this here; http://www.forabodiesonly.com/mopar/showthread.php?t=10508&page=1&pp=20 Click it and read on.

Rumblefish's thread on his conversion has a wealth of information on what it will take to make the conversion, and I agree that the poly 318 is not worth the time or money it would take. It cost me almost $6,000 to perform a conversion, of course mine was with mostly new parts. (See attached list). When you start adding in the radiator, transmission, tourque converter (or pressure plate/clutch), miscellaneous linkages, brackets, pulleys, mounts, exhaust manifolds/headers, exhaust system, etc. it really adds up fast.

IF YOU HAVE TO HAVE AN 8 CYLINDER ..... Your best bet is a donor car that is mechanically sound, use all of the parts you need, and sell what is left to get some of your money back. This way you have all of the miscellaneous items that I mentioned above. Thats what I would recommend......... or find a car that already has a V-8 that is in decent condition and save all of the work. If you spent $2000 - $3000 on a different car that already has a V-8 and is in decent shape you would probably be ahead in the long run.

A slant 6 car can be a lot of fun as well, and a lot easier on the budget. I drove my slant 6 for a couple years and enjoyed it.