wbulick76 Posted October 3, 2011 Report Posted October 3, 2011 Hey everybody. Just picked up a '48 Plymouth sedan, and need a little advice. I did a search on here and a few other forums I belong to, without much success. My original flathead is seized, and I want to upgrade anyways as I plan to drive the car often. The previous owner has two complete motors, and I have my choice of what I want. One is a small block with a 904 (he thinks 318) and the other is a 440 with a 727. I am a big fan of 440's, but can't seem to find any info if this is a practical swap. Looks like 318 fits nicely. Really would like to avoid cutting the firewall. Also looking for info on disc brakes and power steering. Sorry for the long post. Thanks in advance for any info. Bill Quote
Plymouthy Adams Posted October 3, 2011 Report Posted October 3, 2011 there is not enough difference in size of the big block and the small block to make a difference fitting wise..however it is not just a drop in either..a search on this web site will net tip and suppliers..they are becoming more common these days. The 440 is nice but where you going to run it..for a street machine it is basically bordering on overkill these days unless you just flat out looking for bragging rights...the 318 will do all you need for a driver and you will be more apt to drive it with a fuel efficient engine..power steering is a kit from Fatman..brakes can best be had from olddaddy on this forum..(look for him on the member's page) so many thing you can d..you can go econo or you can go wild and outrageous with the build..tthat is only a choice you can make..but rest assured, with the right skill and shop/tool available..anything is possible..you are limited only by your own self.. Quote
littlemo Posted October 3, 2011 Report Posted October 3, 2011 Geez Tim, that was a great reply, and right on !!! Cass, alias littlemo ... Quote
Don Coatney Posted October 3, 2011 Report Posted October 3, 2011 I up-graded my 48 Plymouth 4 door sedan to a Desoto flathead 6, T-5 transmission, Charger differential (1974 3.55/1) and a few other goodies. I have driven my car over 40,000 miles so dependability with a flathead 6 is not an issue. If you further search this forum you will find a lot more dependability flathead 6 stories. Quote
Plymouthy Adams Posted October 3, 2011 Report Posted October 3, 2011 lots of folks it seems do not like the idea of working on an engine that is seized already..it's a known fact that you will need a bore and new pistons..if the crank is in good shape and can be turned the rest of it will make putting it back together a econmical venture..however..lots of folks if going to that amount of work like to opt for a modern driveline..it's all in having fun.. Quote
Don Coatney Posted October 3, 2011 Report Posted October 3, 2011 it's all in having fun.. That part I agree with. Quote
carls 49 Posted October 4, 2011 Report Posted October 4, 2011 hi bill and welcome. good to have you here. don't know about eng swap, but do know i luv the 6 in my 49. Quote
wbulick76 Posted October 4, 2011 Author Report Posted October 4, 2011 Thanks for the replies everybody. If the flattie was running, it would stay in place. The budget is not here for a rebuild of that motor right now. It will get saved though. I am not afraid of some work, and have built hot rods, street rods, and done restoration work on the side and professionally. I am leaning towards the 318 swap, just for ease of install. Really would like to keep stock firewall and all intact. Has anybody done the cavalier r&p swap? Results? Thanks. Bill Quote
Plymouthy Adams Posted October 4, 2011 Report Posted October 4, 2011 TRW makes the rack..not GM as Chrysler also used a version of this rack (front steer) source is Cavalier is all the credit I will give ..lol mount using the Fatman kit that is for Dodge will have you modifying the brackets for the Plymouth more narrow frame..some here have made their own mounts and if you know the geometry for aligning you can easily do this yourself. Pumps are no consequence as the rack has the regulator...input flow is orifice controlled.. using the 318 I suggest the use of the truck center sump oil pan, also the truck center dump manifolds..the late model shorty starter..good pipe bender will give you added starter clearance with a slight in and forward bend before the sweeping curve to the rear..I have a good shop here that bends to my specifications without a problem and does it for an excellent price..if you do not know a good bender in your area, ask your buds.. be prepared to mount the radiator forward..maybe even at that a firewall recess of about 4 inch..this will give you good room..my 41 is 383 with AC and such and has a forward mounted rad and recessed firewall. MY 51 Plymouth is Dodge Dakota V6 plenty of room at the firewall and rad shell but I did modify the rad opening and floated the radiator in the opening..this was done as the hood latch support bracket could not be modified with the amount of metal needed removed to forward mount the rad...it is modified all the same but more for the placement of the AC condenser than the radiator. Quote
Rusty O'Toole Posted October 5, 2011 Report Posted October 5, 2011 The 318 will fit with some finagling. It is not an easy swap, but easier than a 440. The 440 would be way too much motor for your brakes, suspension, chassis etc etc. Don't overmatch your car. Even if you get it in it will be miserable to drive and a gas hog to boot. The 318 will be way better, and result in a better balanced car. If you later want more HP the 318 can be hopped up or replaced with a 360. A good 360 can be made to give 400HP without too much trouble. Quote
Plymouthy Adams Posted October 5, 2011 Report Posted October 5, 2011 and based on a the avg 375 HP 440 what makes the 400 HP 360 better as braking this beast will be the same...actually a good 290 HP 383 will on the average yield better MPG than the average 360 .....and for weight and weak chassis.....not so...pound for pound..the flat 6, cast iron belhousing and tranny..pressure plate clutch etc etc..the frames are full box frames front to rear and the average later model car/truck with the big block was unibody and or c-frame...little COYOTE where E is engineeering Quote
Rusty O'Toole Posted October 5, 2011 Report Posted October 5, 2011 (edited) Tim I never said the chassis was "weak". I was trying to put myself in the questioner's place. He already told us he does not have a lot of dough and wants to get the car on the road and have some fun on a budget. So, my suggestion is to go with the 318. Easier to install, nicer to drive, better mileage, he can have a lot of fun without spending big $$$$ bucks. The 440 will fit, physically. But I would not recommend driving a 600HP 440 on stock brakes, stock tires, stock rear axle. To do the job right will cost a lot more than putting in a 318. Not so much the cost of the engine itself, as all the mods you need to do to make it safe. Now if the owner wants to spend the money on better brakes, suspension etc at a later date the small block is not hopeless. He will not be wasting his time or money putting in the 318. If he wants more power later, a hopped up 318 or 360 will fit in place of the stock 318. But for the time being a stock, 2 barrel 318, 180HP will work well with the stock suspension etc provided the driver is half way sensible and does not give it the works all the time. A 440 would just be overkill without major, and expensive, chassis mods. Basically I was agreeing with your original post. You said the 440 was overkill before I did. I also agree that the Dakota V6, like you put in your 51, would be a good choice but he did not ask that. Edited October 5, 2011 by Rusty O'Toole Quote
Plymouthy Adams Posted October 5, 2011 Report Posted October 5, 2011 the 440 is over kill for the street should you goal be oriented to a driving car for fun and occassional run for groceries and family outings....but I also said that only the owner can make the call on what he wants for a driveline..I have never seen a 600 hp stock 440 in any configuration..as for cost..the 318 is abundant but on the average you can also get a motor home 440 or 413 with 727 for about the same coin and these are usaully lower mileage babies and as coming from a truck chassis will have the components one will desire when doing a swap...your reference to the chassis could only be taken in the form of being weak no manner what you thought it was that you wrote as you addressed the chassis and suspension seperately...no need to argue any point really only that these cars can take about anything you want to throw at them..being realistic is the key to the build and the individual again is the only responsible party there..engine weight pound for pound is almost equal based on available engine estimations found here and there..agreed on all accounds that brakes need to be updated if you are running serious speed or handling manuevers you will want to definetly relocate the front shocks and maybe address the sway bar a bit..318 or big block..both will be pushing the limits of stock due to their flat out available power on tap over a stock flathead..so yes any V power and I do include the V6 as my 93 engine is stock at 185 HP..single year version..but then I have all modern componets onboard and on the chassis..I have installed the 3.9 V6, 318, 360 and 383 in these puppies..all are about the same involvement..with less massage with the V6..I even put a 440 in my 41 Dodge military with 4WD..easiest of them all..even converting the Porsche gauges (tach) to V8 was a breeze point is for ever one who comes here asking if this or that can be done usually 99 percent of time it is a yes and we have people on here with ownership of said setups and features already...and have had them in that configuration for years.. if a person comes on her and starts out that he wants a super HP monster build..I usally just go to the next thread and provide little to no input..why..its impractical and I have seen more ruined engines overbuilt for the street that I care not to even learn of their intent..so next thread and move along..a 292 and up cam is not designed to be idled on the street..and if you do..you best be running low pressure springs..but then you just cut the top end of your engine and its ability to utilize the installed cam..I sold not long back a 560 HP 440 because it has no use on the street..(I got it on trade) it is now in a proper 68 Roadrunner as it should be..everyone wins.. I believe most folks are taking exception to the input as not advice but the only way is your way build..but even at that it is not nearly as bad as most folks on a few other forums..and with that..again...'nuff said Quote
wbulick76 Posted October 5, 2011 Author Report Posted October 5, 2011 No, not looking to build a 9 second street machine, just a nice reliable cruiser. I have my choice of a 440 with trans or a 318 with trans. The previous owner has both and with the purchase comes either one I want, so the engine cost is not a factor. I am capable of fabricating some mounts for either choice as well. My one requirement when I got it was that it remain Mopar powered. My Dad built a '41 Plymouth coupe as a street rod in the late eighties that was powered by a six pack 340. I remember riding many miles in that to street rod shows. Left quite an impression, apparently! Quote
Rusty O'Toole Posted October 5, 2011 Report Posted October 5, 2011 Hey Tim it was just a suggestion. I'm not going to jump out of the computer and force anyone to build anything they don't want. Like you I have seen beginners get in way over their head, thinking they have to have some super racing motor like they saw on TV. (they don't). Have also seen more experienced guys build very clean, well done, cars that do not draw a glance from the general public, but are as practical and enjoyable to drive as a new car. When I talk about a chassis I am thinking about more than the frame. The chassis also includes steering, suspension, rear axle, springs, brakes. If I mean the bare frame I will say frame. We seem to see eye to eye on most things. Have a nice day. Quote
ButchsCoolStuff Posted October 7, 2011 Report Posted October 7, 2011 The 318 will fit with some finagling. It is not an easy swap' date=' but easier than a 440.The 440 would be way too much motor for your brakes, suspension, chassis etc etc. Don't overmatch your car. Even if you get it in it will be miserable to drive and a gas hog to boot. The 318 will be way better, and result in a better balanced car. If you later want more HP the 318 can be hopped up or replaced with a 360. A good 360 can be made to give 400HP without too much trouble.[/quote'] OK, the 318 will fit fine. If you are staying with stock steering and column you just need to offcenter the engine to the pass side about 1 inch. If you decide to use that Fatman's Power Steering kit, then you can mount it centered, no problem. We make the kits both ways at www.butchscoolstuff.com. Our kit also come with a trans crossmember that will clear the brake pedal mounted on the frame. We also offer a NEW pedal kit with booster/dual cyl, that bolts into the stock frame mount. Plus check out our Rear End mounting kits that include Gas Charged shocks. Later, Butch in Dayton Ohio Quote
wbulick76 Posted October 7, 2011 Author Report Posted October 7, 2011 Thanks, Butch. I have been eyeing your stuff for a while now. I'm a native Clevelander, and grew up in hot rods back in the Butch's Rod Shop days. I am leaning towards the 318 as opposed to the 440 for ease of install. I really don't want to set the firewall back, even though I am a big block guy at heart! Quote
Plymouthy Adams Posted October 8, 2011 Report Posted October 8, 2011 compare the dimensions of the two blocks and then tell me what you think.. you will find that the small block is 1/2 longer than the big block..only 1/2 shorter in height than the big block..but with air clearer the small block is 1/2 taller...only real measurement of concern is the width and as that is mainly top width of the valve covers....and as most of this will sit above any suspension component..there is relatively no difference in the installation..I say this as width is hardly the issue..I know I stuck a 440 in a shark nose 41 Military 1/2 ton..even there it was very doable..and you will find that with just a bit of owner massage of some metal the C171 will fit the big block using small block brackets..the lower small block pulleys will go n the big block balancer.. and I will only say the list goes on and on..you have your choice of side for the water inlet by what component you choose..these are very versatile engine..easy to work with...using the 727 is also a walk in the park..even the front wheel drive shifter will snap lock into place by simply using the later model shift belcrank..and use the late model floor shifter or column shifters if you choose to upgrade the column..using the Ididit column is the first step to a trouble connection..stick with the complete stock system as supplied over the years and have total interchangeability.. Quote
baiyiwong Posted October 12, 2011 Report Posted October 12, 2011 hi, anybody need diagnostic tools? i own a online shop, it sells all kinds of diagnostic tools which include obd2 auto scanner, auto diagnostic scanner, launch x431, odometer correction tool and immo key programmer. All car diagnostic products from scannerobd2.com are genuine ones, we offer genuine obd2 auto scanners, genuine auto diagnostic scanners, genuine launch x431, genuine odometer correction tools and genuine immo key programmer too. all the orders will be processed in 2 days and shipped out in 3 days, and then there will be a package tracking No. if any question please feel free to write to us(you can find the contact information from the homepage-scannerobd2.com Quote
Don Coatney Posted October 12, 2011 Report Posted October 12, 2011 hi, anybody need diagnostic tools? i own a online shop, it sells all kinds of diagnostic tools which include obd2 auto scanner, auto diagnostic scanner, launch x431, odometer correction tool and immo key programmer. All car diagnostic products from scannerobd2.com are genuine ones, we offer genuine obd2 auto scanners, genuine auto diagnostic scanners, genuine launch x431, genuine odometer correction tools and genuine immo key programmer too. all the orders will be processed in 2 days and shipped out in 3 days, and then there will be a package tracking No. if any question please feel free to write to us(you can find the contact information from the homepage-scannerobd2.com Great looking tool. Can you tell me how to use this on a P-15 engine? Quote
Plymouthy Adams Posted October 12, 2011 Report Posted October 12, 2011 gee Don its quite obvious really, you place behind rear wheel when parking on an incline.. actually that can be use on my 51 Ply. Suburban..except...Chyrsler has already built this into the ECM.. Quote
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