I want to replace the SBC in my '38 Chrysler with a SBM just to enhance its Mopar-ness. I'm a pretty mellow driver, but the car is a big, heavy beast: probably a smidge over 4000lbs with a full tank and me and the wife aboard, so I figured a 360 would be the ticket: Lotsa torque but not too big/heavy itself. When I read the h.p./Torque numbers for the stock 360 engines they are not that exciting. The very mild 350 I'm going to pull out is rated 260hp/300tq. I'd like to do better than that, but nothing super if required: maybe 350ish torque. What I'm looking for is a recipe (for dummies- I've never built an engine and may be hiring out some work) for a reliable, economical LA that'll give me a little more Oomph. I spent some time on the "For A Bodies Only" site and only got more confused: those guys are very knowlegable, but very much racing oriented and can discuss the fine points of various cams till the cows come home. It makes my head hurt. Just looking for a simple & complete step-by step on block & parts selection, and machine shop work. Extra points in my book for cheap(er) & more reliable suggestions.
Gotta say, your "cheaper and reliable" comment ... well, you already have a SBC, doesn't get anymore cheaper or reliable than that (in my opinion). As for power, I had a 1971 340 years ago that was rated at 275 hp (10.5-1 compression stock...too high for todays fuel). Mopar had a "Direct Connection" book that showed how to build different engine to certain power levels (now that I think about it, I think the builds were for "how to get a car into the 13's, how to get a car into the 12's and how to get a car into the 11's ... should give you all the info you need though ... won't exactly be up to date, probably printed 20 years ago). Check eBay for that. Is changing the engine really going to make you happier? I say keep the SBC. Lots of work to change the drivetrain over to Mopar (engine and mounts, trans and mounts, driveshaft length etc). Enjoy driving your car and only open the hood when it's time to change the oil. Just to enhance its Moparness ... not worth the cost if you ask me (and yes I realize you didn't really ask me).
Look here, Mopar small block crate engines. Performance specs don't sound too bad to me. Click Magnum small blocks http://www.mopar.com/performance/features/crateengines/index.html
When moving away from the SBC, the choices narrow, but the info is there. LA is the 283/318/340/360 family. Mopar offers crate engines. Price them at one of the big dealers and Summit/Jegs. http://www.moparmusclemagazine.com/techarticles/32698_mopar_crate_engines/index.html other parts http://www.moparmusclemagazine.com/...opar_small_block_performance_parts/index.html and there are manuals available for builds http://www.amazon.com/Small-Block-Mopar-Engines-Present-273-318-340-360/dp/0895864797 Try moparts.com general (not race) section too, although some people here don't like the place. A lot of people are building the magnum engines (318=5.2, 360=5.9) and getting good street power easier with the right parts. They have roller cams and good heads (avoid the crack-prone castings).
The 360 is a bit more expensive than a 350, but....find a rear sump one in a van or pick-up. Then up the comp a bit & a little more cam & a nonretarded timing set. Drop in the engine/******, have a shop change the ****** end of your driveshaft.
Even if it cost a little more do it, my uncle in law has a 39 Chrysler with a 340, drives awesome and has good power with just a stock rebuild and a little cam, intake and headers. I love chevys but nothing cooler than keepin a hot rod all mother mopar.
Well a couple of things have been said already that make good sense. One of them is - just leave the Chevy alone. I know you didn't ask me, but if it runs well, and there is nothing wrong with it, leave it alone. And that is coming from a Chrysler guy. See, my car has been a pursuit to build maybe not the ultimate hot rod small block, but maybe the most well rounded. I can tell you, the honest truth is that I have spent roughly double to build my 360 that I would have to build a Chev 350. If I were looking at a clean sheet build for a tourquey small chrysler, I would start with a later model Magnum motor. The heads are far superior to the earlier stuff. Do thorough rebuild being careful to get the compression ratio up to 9.5 to 1. This is going to take some decking of the block, and Kieth Black makes a n excellent piston for this deal. I would then talk to Comp Cams, or Hughes Racing cams, and be ready to supply gear ratio, weight of car, converter stall, and tell them what you want to do. Then, and this is the most important part, listen to what they recommend. Buying a cam for a specific purpose means that your ego has to go away,(toughest part for a guy like me!) They can supply you with the right cam to get the job done. Good thing about the Magnum motors is they're roller cams right out of the box. The two cam grinders I mentioned are important, because they are the two that have really stepped up, and designed cams that are specific to our needs. Most every body else does they're research and development on Chevys, then uses those grinds on everything. The small Chrysler has a larger diameter lifter that can allow a cam to utilize a much steeper ramp to move the valve much quicker. Up top, Eldelbrock makes a manifold called the Performer RPM Air-Gap magnum. That's a mouthful, but it has been proven many times over as the best out there. Feed it with a 600 - 750 CFM Holley vac secondary or Edelbrock carb. Fire it with Chryslers electronic ignition or MSDs stuff, both work well. Nothing exotic, but if you are careful with the compression ratio, timing, and carb tune, this will get you in the mid 300hp range, at about 400ftlbs. Plus you'll never have to worry about it. When your all done with the motor, dig up an A518 overdrive trans from the late eighties, before they went full electronic, and get a converter set up for about a 2200 stall, and hook up the lock up feature. Rear gears should be around 3.55 or so depending on the tire height. This would be a great, mellow, and powerful set up that will give you zillions of happy miles.
Don't worry too much about a 4000 lb car. If a 350 is providing reasonable performance then a mild 360 will do every bit as good since it has a torque advantage. The late Magnums are a good choice especially if you keep the fuel injecton although a carb manifold is available. Early truck and van 360's can sometimes be had for little more than s**** value. If you have ready cash to drop on a crate engine then go to your dealer and buy one of the mild 360 packages. Mopar Performance has released a bunch of Crate Motor ***emblies for those who want their power plant to be a one-stop-shop. Options include $1,500 performance-built short blocks, $3,600 360 small blocks, and all of the heads and intakes to complete the package. At first blush those prices may seem a bit steep, but those are prices suggested by Mopar Performance. Most Mopar Performance dealers are selling them at deeply-discounted prices, some as much as 25 percent so shop around. If you don't like the 'crate engine' stigma, then buy a copy of the Mopar Performance Engine Manual and start reading..and buying parts. .
I appreciate all the input. This is one of those things where there really is no reason I have to make a change- the existing sbc runs fine- but its been in the back of my mind to make it all Mopar anyway; I just wasn't in any hurry to do it. Then last month I happened into a never-installed TCI-built 727 for a give-away price so I got a transmission and am kind of backing slowly into the swap. I figured if I can build/buy an engine at a reasonable price I'll do it, but didn't really have a clear idea of what I was looking for. I don't mind doing the work (much) as I'm one of those who enjoys the work as much as the drive, and I like to have the winter's project figured out ahead of time so I'm asking questions & planning now so I can decide if I'm going forward with it this winter. Truck engines (though maybe not Magnums) seem to be easy to find at a pretty reasonable price but then I just wasn't sure how/where to go from there.
Oh- and I have no ego in the way of taking good advice, and no objection to a crate motor at the right price. I just didn't realize Mopar Direct had those options- all I'd seen was the $5500 "Blueprint" remans in the Summit catalog. That's a bit more than I want to spend, and seemed a lot of $ anyway for something without the best reputation.
I'm confused, how did a '38 Chrysler suddenly become a 4,000 pound car?...if I recall correctly, my '40 plymouth 2 dr sedan came from the factory around 2,600 pounds...hell, my '63 Dodge Custom 880 is barely a 5,000 pound car at most...and that's one big pig of a car...
I have done many 360s. They are a very good and very inexpensive motor. I like to find one with J heads if possible. I put the 202 intakes from the 340 in them. do a little clean up in the bowl directly under the valve and gasket match the intakes. You can also clean up the exhaust ports a bit as they can be a bit irregular. find the best one , make the rest the same. For a cam the comp cam extreme hydraulic XE268H. it will work with a stock converter although any improvement in converter choice will benifit any combo. You will need a decent set of valve springs as well. I often use the MP perfomance upgrade for 340 springs . A couple of companies now make a 9 to 1 compression piston . stock was called 8 but often had a hard time being mid seven or better. I believe Fedral has or had a 9 to 1 as do a couple other companies or for very few $ more KBs which are around 9.6 I believe. Stock rods are MORE than adequate for the job. I like to make sure it has a 340 style windage tray. If momma mopar is out of stock then milodon can often supply a decent alternative. i use the stock 340 chain and ge****t. Do Not use the shiny blisterb packed **** with multiple keyways. Quality on many is very low and quality in the stock 340 set up is very very good. Very accurate set of gears they are. Piston clearance should be .001 per inch of bore. which would be .004 for me if i was doing it. Intake should be , almost must be a Performer RPM and a 3310 holley with 5.0 power valve and 75 pri and 78 sec will do a wonderful job of making power. Use the lightest spring in the vacuum secondary diaphram housing from the holley secondary spring kit. ThROW the check ball away!. A new Mopar electronic distributor has adjustable advance curve with out dis***embly. I recommend it. Adjust the curve for 2/3s of total avaliable . Do not run the vacuum advance. Last one I was involved in was in a 70 Dart with auto. It will idle at 550 in gear although it would be happier at 600 i personally think and he drove it to the track and ran it just to see if it would run decent. He was shocked to get a 13.05 at 105 mPH. This is a not a race car. And yet with just a tickle or probably a bit of traction it will be in the 12s. It was supposed to be his wifes street ride. I doubt she gets to drive it much now. I know you would be happy with this combo. It has hi torque, decent power, good manners and is an inexpensive but extremely reliable package. i have done several of these and have not heard diddly neg about them. Usually I hear they are shocked at how much power it has. First one i did was when Comp first came out with the extreme hydraulic series for these engines and they did not have one on the shelf yet so made it and sent it here within the week. If you and you friends decide a mopar shaft would be better you can kiss about 50 hp goodbye. Don
I've seen the curb weight for my convertible in books rated at 3600-3800lbs. Then add a couple of people... I have a '50 wagon parked next to the '38 convertible in the garage. The wagon holds 9 p***engers. The 'Vert holds 2 (plus maybe 2 kids if you count the rumble seat...), but is bigger in every dimension. It is pretty big.
I think I figured it out. Chev and LA have dist in back ... just drop on an old 340 aircleaner and machine up some adapters for the valve covers ... then (with all the money saved from not having to actually do the swap) go to a hypnotist and let them make you "think" you actually have a 340 under the hood . Make sure you wife knows the truth and send her out for parts (she still knows it's not a 340 and will order the correct Chev parts). Don't get me wrong, my 1971 340 Duster was a blast to drive. It really was a great engine. I actually still have the 2.02 heads in the ba*****t (J heads with factory 2.02 valves ... everyone thinks just the X heads had them, but that wasn't the case). It just seems like a LOT of work (and money) just so you can say it's "all Mopar". But hey, you gotta do what you gotta do. Oh, one more thing. San Jose Cali has a winter? When did that start?
Huh, perhaps the Plymouth's in the early 40's were smaller and much more stripped down...of course, mine tips the scales around 2,500 right now with a 400 Pontiac and '61 Pontiac Powerlok rear stuffed into it, so it's been stripped down quite a bit further than stock ...I'm considering swapping in a mopar motor once I get shop space again, just to make her period correct and "all mopar" (except for the Poncho rear, that baby's staying put)...good luck with the swap, man...sell that belly****on motor and have some fun the way Ma Mopar intended...
i've got a 360 .060 over with a 4 inch stroker, Eagle rods, eddy alloy heads, rpm performer intake, Holley 850 and an old school cam with a touch too much overlap. - at 415" the purple 292 cam is still plenty mild-although i should have picked the wider lobe separation angle but it pretty damned tame and twisted the pump to 520lbft and 462 hp with a nice flat curve seriously torquey! this is a VERY streetable mill with tons of torque- had it in a 4100lb fuselage body fury with a 904 that had the low ge****t from a 70's Dodge truck- 2.76 first instead of 2.45. That car on tire with a 3.23 lincoln locker regularly punished bolt on equipped mustangs as long as they weren't on bottle... if you want torque - any 318, 340, 360 will respond VERY well to strokers - they have wide pan rails to easily handle the big rotator, 18degree heads stock, stable shaft rockers, 6.123" rods stock, and weigh within 25-35 pounds of sbc (iron vs iron- bigger alloy LA heads bring it closer when comparing alloy vs alloy) REMEMBER chances are good that you already own at least one 360 and two 318s. just look around i bet you'll trip over one in your back yard.....
Chevy guys are funny. LA motors are great, far more reliable than a SBC, and they make more power for the buck, even though they may cost a few more bucks (but certainly not twice) than what a SBC does. I noted with some interest the Blueprint engines catalog. If I'm not mistaken, the Mopar engines they build make more torque and HP than any of their Ford or Chevy offerings. I might be mistaken, again, but that's how I remember it.
speaking of blue printing.... Local machine shop run by a mopar guru that competes his dual quad hemi cuda- he told me that mopar mills always measure out big- the reason that my 360 truck motor measured 7.8:1 instead of the expected 8:1 compression. when you blueprint them they gain lots more than expected- but who stops at 8:1- lol i'm at 10.15:1 which i'd like to lower a skosh for my paxton g***er build. rick
A few random thoughts... since I have a 39 Chrysler I'm slowly putting a Ford 302 into. Like you I'd rather have a Mopar motor, but I got the rebuilt motor and trans for $300 and I couldn't p*** it up. I also got a Ford 8.8 rear end out of a Explorer (disc brakes, right width, takes stock wheels) so I have a whole Ford driveline. It drives some people crazy. I've told a couple of Mopar fanatics that if they'll sell me a 318, 340 or 360 for the same price (freshly rebuilt like mine was) I'll go that way. No takers yet. Getting more power out of the Chevy might be easy too, a nitrous kit under the carb for example - this would later transfer to another motor? If you don't get a OD transmission you might want a lower rear end ratio - 3.08 or 2.73. Bottom end torque (just off idle) will help a lot with that and give you smooth takeoffs - that was Cadillac's secret. Just for fun.... I once had a book called something like "How to build big-inch Mopar small blocks" which showed how to stroke the motors, back before the internet made finding the parts easy. If you are going to rebuild a motor (you can probably get a high-miles but running 360 Magnum cheap) then consider going for more power and torque this way. And then get a 273 air cleaner + decal on the carb...
Chrysler = biggest ch***is of the MoPar clan; Plymouth = smallest. Considerable difference. BTW, if you're really worried about moving a 2 ton tub, it's real easy to put plenty of stroke in an A motor. There's a guy building a 501" one on Moparts.com using an aftermarket block. But guys are sticking a 4.25" arm in stock blocks (2.0" rod journals and grinding the block)... doing the math on what that comes out to with a 4" bore like a 360 block gives 427 CI. Think that'd do it? And, yeah, the crinkle valve covers and air cleaner from that 273 Commando will go on (and since they used a single plane on that engine, you could grind the name off your Victor or whatever, and just paint it...) nobody'd ever know. -Bill
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