I'm trying to make a decision on what engine goes in what car. There is always logical reasons for either combination. First the 39 Plymouth truck is a driver with a 360 and TF. Its been a driver for 10 years. I hate 360s. GASHOGS. I'm sure I could spend lots of money and make more power and probably get better fuel mileage. It's a 78 smog motor and about the only thing not stock is the intake, carb and the cam. I drove it to Ft Worth from Pensacola and my wife drove my 2005 ram with a ***mins diesel towing a loaded 24' enclosed trailer. I got about 1&1/2 miles per gallon better mileage with the 360 running a/c than the ***mins did loaded. However there is something to be said for dependability. The 39 is dependable. It is time to update. Do i put a 318, which I have 2, with an overdrive in the 39 and a 354 hemi in the 41 Plymouth coupe, which I have, or the other way around. The 318 is a bolt in swap in the 39 and the hemi would require a lot more work. The 41 is ready to build and it has a larger engine bay than the 39. A Plymouth truck is rarer than the coupe and in my opinion would be worth more with the hemi than the coupe. The other consideration is I have a second cab for the 39 that has been extended 6" chopped 2" and has the fire wall already recessed. The picture of the 41 is prior to being media stripped. I was removing some bright work. A friend with a restoration shop in Florida stripped it and put it in epoxy primer for me before I brought it to Ft Worth. The cab had a lot of work done before I made the move to Texas and has more to be done. Let me hear what you think and maybe someone will think of something I've missed.
"From P'cola", thought that truck looked a bit familiar! Hemi would go in the bigger bay easier than the small bay. Would need to flatten/recess the firewall for it especially if you have the OEM front frame. A Camaro/chevelle/Cutl*** or other rear sump subframe would help a lot with fit. Not sure about the '39, but if the '41 is like the 46-8s, the 318 will fit with only a dent on the p*** side firewall for valve cover clearance. Of course the 318 inplace of the 360 would get you back on the road quickly. What is the 360 getting for MPG? 318 doesn't often set the world MPG records itself. Usually 1st thing to do with a 318 is toss the intake & get new intake & 4 bl. Is the 318 rear sump yet?
My 2cents. Put the overdrive trans behind the 360. A 318 is not going to gain much mileage over the 360, but the overdrive would help either. i got almost 16 mpg from a wore out smogger 360 with a 727 bolted to it in my 54 pickup. The fresh built 318 in my 35 Dodge with a 904 only got 17 or 18 on a good day. The truck was probably several 100 lbs heavier then the 35 sedan. Of course, if you have a grudge against the 360, swap in the 318, but any improvement over the 360 will come from the trans, unless your leaving that 2bbl on the 318. The Hemi would fit better in the 41 then it will fit in the 39, but I have some bad news if you think that Hemi is going to get better mileage then the 360 gets. Mopars were not known for high gas mileage. Of a whole bunch of them I've owned, the best real mileage from any V8 auto was pretty near 18 mpg. Gene
Who cares about mileage when you've got the looks of the hemi. If I have to put up with lousy mileage then it has to look the part.
George the 360 is got about 14mpg on the trip to Texas. I have 2 or 3 truck pans for the 318s. Right now the 39 has an 8.25 rearend from a 74 Duster. The really bad thing is it only has a 2.45 gear. No power and still no mileage.
I actually gained mileage with my pickup when I went from a 2:76 gear to a 3:23. Took less throttle to get the truck moving, so I was out of it sooner. The OD would have knocked the the highway rpm down but left me with a decent gear to get the m*** moving. Gene
This is a very biased opinion, but I would put the Hemi in the coupe. A few alterations are required but this would make an awesome combo.
Yeah I think a 318 would do better with a 3-3.23 than a 2.76, even more so with a 2.45. The 360 should handle the 2.45 better than a 318 would. Had a Ford S/W that didn't seem to like towing, found out it had 2.25s! Had a Crown Vic P.I. with 351W, AOD & 3.00, still didn't get 20 MPG but acceleration was fine.
Just how well does the 360 run? I fondly recall a 79 Cordoba that I drove for several years...360 lean burn, 2.45, and fairly consistant at 20mpg. The Cordoba is not a light car. Maybe you should freshen up the 360..? An A500 with a 3.55 rear nets the same 2.45 but will be easier to drive around town w/o the OD turned on. As for the 354, It will look good anywhere! .
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