340 or 360 for 66 Barracuda?

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eholster

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I'm making some motions to do an engine swap on the Barracuda but have run into a bit of a stumbling block - After looking at options for small blocks I'm a bit torn on what to put in. I've found a couple 340's, both complete and runners (though likely needing a rebuild) as well as a couple 360's as well as a set of magnum heads. Which route to go????
I like the idea of the shorter stroke, higher revving motor, and I imagine that either way I go will be a bill at the machine shop and an extensive parts list.
I know there's LOTS of opinions out there...:director:
 
I'd use the 340 because of the main size. Install a 3.79 stroke with a 6.200 chevy rod. Rod ratio is good also.
 
If you like saying "It's a 340.", get a 340.

If you don't care, get a 360.

Both are a solid foundation for a street build but used 360s cost less.
 
I would say 360. The reason a stock 340 is better is cam and compression. You're not building a stock 340 or 360, so you can choose your parts. As a plus, you get 20 more cubic inches.
 
360 all the way. I'm "hopefully" getting mine rebuilt this summer. If it doesn't cost too much maybe I'll get a 400 small block with a mild cam and higher compression pistons back from the shop. :) good bye 7.25 rear end.
 
Built equally the 360 will make more power, 20 more cubes. As far as reving the 360 has a much lighter rotating assembly due to the shorter and lighter pistons so there is no real difference in the ability to rev between the two engines.
 
Either will do. Although, I dig the nostalgia of the 340 and always dreamed of building a car with a 340 in it. I remember my uncle telling me stories about his bad *** 69 340 Swinger.

On another note. A newer roller 360 would do nicely.
 
Buy the 340's and sell them to some that just has to have a 340; take the profits and build a 360. The main bearing size thing is a moot point. Unless you're making over 500 hp and spinning past 7500 rpm, you are never gonna know the difference. 360's are less expensive to build, and if you think of specific out put(hp per cubic inch), they will make more power than a 340, with a better torque curve.

Just my opinion
 
Buy the 340's and sell them to some that just has to have a 340; take the profits and build a 360
Click to expand...


i agree. either will get the job done. give me the torque of the 360.
 
If you're really ambitious, find a fuel injected 360 with computer & wiring harness. Rebuild the engine for the power you want out of it.
 
Thanks all, for your replies. Didn't mean to leave the thread hanging with all the input and no response... Busy with the day job, night job (15 y.o. daughter - lot's of overtime!) and had a work related trip to Central America...
But - I did manage to find a 360 Magnum local for a fair price. I went through and re-read the posts here and now have a bit to consider - the motor is a completer runner, with almost all ancillaries included. This means if I want to I can retain the fuel injection. I also ordered a couple of the "How to..." books - Larry Shepard's How to Hot Rod SB Mopar Motors and Jim Szilagyi's How to Build Big Inch Mopar SB, the latter of which is very informative. In particular I found his recipes on 6 different engine packages interesting. Anyone here have any experience with his 'recipes'? I am specifically interested in the Magnum Muscle Car 408 build, as the motor I'm buying is the basic core for what is laid out. For those who haven't seen the breakdown, here it is -

4.030 bore / 4.000 stroke
block - Magnum 5.9l
Crank - Forged Mopar #P5007254 - internally balanced
Damper - stock 318 w/ neutral balance
Rods - Eagle SIR
Pistons/Rings - Diamond #51405, Speed pro moly
Oil pan and pump - Moroso deep sump # 20730, p/u #24700, Mopar #P4286589
Cam - Hyd roller cam - Mopar #P4876348 230/234 dur. @ .050, .0501/.513 lift, 108 deg. centerline
Tappets - Hyd. roller - included w/ cam
Pushrods - Stock Magnum
Rocker Arms - Stock Magnum
Cylinder Heads - Mopar Magnum R/T - Big Valve #P5007141 w/ porting done
Intake - Mopar M1 Single PLane #P5007380
Carb - Holley 750 cfm
Ignition - Mopar #P3690426
Ign. timing - 35 deg.


The claim is that it will make 505HP @ 5900 and 525 ft-lb @ 3800. Seems impressive... Realistic??

I'm going to price out parts to stroke it. I already have a pretty good idea of the bill at the machine shop. Then there's the whole transmission component to determine...

Another day.
 
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