Hi, I have a dodge dart swinger 2 door that I am building a 1974 360 steeel crank (stock stroke) small block engine for. I have what I think is a 340 mopar purple camshaft that I do not know the specs on, but I have the random numbers off of it. "F7" "1136" "C1" and on the end of the cam (back side of cam): 970799. If I could get any specs on this, it would be much appreciated. But, I want to run as much possible compression in it as I can on 93 octane pump gas. 9.3:1? 9.5:1? 9.7:1? 10:1? (I want to fit 340 pistons in this engine out of the various sets i have with various dome amounts to replace the previous 8.4:1 dish pistons which only came up to .080" below deck height fully exended out.) I have a dual plane edelbrock performer 360 aluminum intake and an aliminum edelbrock single plane torker intake, 750 cfm 4 barrel...( ok size?), stock 1971 360 "J" heads for it completely redone (with the 1.88 intake and the 1.60 exhaust valves), 1 5/8" long tube headers, would like 2.25" dual exhausts all the way back, I would like to run a stock converter and drive it every other day or so with some good get up and go tire smoking power and something that will make power up to around 5500 rpm...(is the rpm range possible with the stock flow heads, with biggest cam allowance for my application, and one of the 2 intake combos?) If the cam I have is not for my application, then which one is?? And with max compression on pump gas, biggest cam allowed for my future application, how much horsepower should I expect, what kind of idle/ range of power do I get, and will I see any increase on torque over stock '71 specs? Please Advise!! -ANTHONY
somewhere there's a mopar forum that will help you out....although if you had read the rules and not mentioned it was going in a 70 dart we might be able to good luck getting a cam that works well with a stock converter, to make power up to 6000 rpm
http://flag.blackened.net/mopar/camchart.html It's been a long time, but IIRC... Unless you have a very early (pre 1975) block, the standard 340 piston (4.040) is the LIMIT on how far you can overbore a 360. I believe the 340 and 360 used the same length rod, which would mean you have a pin height difference as well because the 340 had a shorter stroke (318 crank). Very few 360 cranks were forged, BTW. The best small block I ever had was a 030 over 360 with ported "X" heads off a 340. Isky 486/270 cam and it would run to 6000 but that was it...
Try the site http://www.forabodiesonly.com . It is like the HAMB for Mopar A body cars of all years. Conor
Its a early 1974 360 engine and I was thinking that the lower wrist pin location and the bigger dome on the 340 pistons would pop higher than the old ones and give me better compression...
you can buy new pistons at summit or jegs that are better than the stock 340 ones and choose your own compression. I had a 360 in my duster, had a huge lift, long duration cam and roller rockers, holley carb and elderbrock intake and that thing hauled ass. could get it up to 7000 rpm easy! daily driver too! Unless the 360 came with a manual, the crank is cast. If you want it to be faster and spend less money trying to fit the 340 pistons in buy higher gears for your new rearend. If it has a 7 1/4 in it still, it will not last long. Or even better option....BIG BLOCK!
3..31 vs 3.58...?! That's .270 worth of pin height! ... 2X on the A body site. Learn a little more about what you've got...
Stroke that 360 to a 408 or 416 .The stroker kits for these Mopars arent that expensive anymore .There is not alot of meat to have to relieve off the block for clearence on these Mopar blocks either.Forget a Big Bolck Mopar ,pound for pound and dollar for dollar a stroked small block 408 or 416 will walk all over a 440 .Real easy to get 450 to 500 hp out of a stroker small block and keep it streetable at the same time on pump gas .Go to the Unlawfull's racing forum on Moparts ,or the Racing forum at Forabodiesonly and read up ...
That carb is to big. What kind of RPM's are you planning for your motor? I could tell you what size if you told me the RPM range you would be running it at.
Mitchell is correct on the 750 being too big for a street 360.IMO thats one of the biggest mistakes that people make on their motor ,is too much carb .I would think a 650 would be alot better choice on a hot street 360.BTW ,please go back and change your title on the thread and the first sentence of your first post and get the "1970 Dart " stuff off or it will proly get deleted.This is a 64 and under forum ,but we can certainly talk about your 360 if we dont know what your gunna be using it in, lol.These LA motors dont get the recognition they deserve IMO ...
Purple stripe is a duplicate of the street hemi cam,.508 lift. you need adjustable rockers to see its potential, the shim kit for the flutes is just too hinkey, and if ya go over 10.5 on the compression, ya need to stud and o-ring the heads, that 4 bolt per hole just dont cut it, you will push gasket between 2 mid cyls every time, and as far as top end, i swung my 340 to 9 plus k every pass and left on the mat wihth a 4 speed. this was a hi 10 sec conbo with 4:56's and 31x10.50 d5's
By the time you start changing this and that you can either do it one of two very easy ways . 1- get a stroker kit ! 2- just by a good engine from Summit and be done with it ! There are also Mopar forums on the HAMB ! These are the easiest ways and takes all the guess work out . Doesn't take much to smoke tires ! RetroJim
If sounds like maybe you are somewhat new to the world of engine building so I'll offer my usual bit of advice: Buy a copy of the Mopar Performance engine handbook and follow their suggestions. Remember that they designed the engine and that they have invested millions of dollars in research for various 'packages'. Yes, racers have developed many useful variations and some guys make phenomenal power with dubious combinations, but you are wanting a daily driver so why reinvent the wheel? My second recommendation would be to scrap the small block and install a stock B-RB engine. .
NO 360 cranks were forged - all are cast and externally balanced. Also, go to either www.moparstyle.com or www.allpar.com These are very good Mopar sites, without all the BS drama of moparts.com BTW, that 750 carb is too damn big for that 360. Go smaller, like a 650 or so.
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