340, 360, or 400?

[BrianT]

This guy's been selling these kits on Ebay for a couple of years now that I know of. Pretty cheap and would make a nice little street engine.

http://cgi.ebay.com/ebaymotors/SB-MOPAR-360-408-STROKER-EAGLE-CRANK-RODS-ROSS-PISTONS_W0QQcmdZViewItemQQ_trkparmsZ72Q3a543Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318QQ_trksidZp3286Q2ec0Q2em14QQhashZitem270307445263QQitemZ270307445263QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories#ht_1081wt_0

He's got other kits available if you want to go forged crank or H-beam rods. Whatever your budget allows.

 

[racerbob]

If the 340 is a high compression/steel crank engine I would build the 340 , while using the 360 currently in the car. Depending on the condition of the 340 you can probably freshen it up for a lot less than boring and stroking a engine. Once you complete the 340 then swap the engines and you have the 360 as your next engine project (going faster and building engines can be addictive!). This option probably fits into your $2000-3000 budget.

If the 340 is a cast crank low compression engine ('72-73 model) or if it needs oversized pistons due to cylinder wear, you may want to consider stroking it. This will cost more than your original planned budget, depending on how much other stuff you need get (heads, intake, valvetrain, etc.).

If the 360 in the car is in pretty good running condition you could just try some bolt-on performance parts (Cam, intake, headers, heads, ignition, fuel system, etc). This may get you the performance level you desire without the hassle of changing engines. This could easily be well within your budget, and much of what you buy (intake, heads, headers) could be used any later installed SB engines.

Since you have two SB engines I would stay away from using the 400 in this package. I would also recommend keeping a running engine in the car while you are performing a major overhaul of the other engine. That way the car will still be usable if you run out of funds in the middle of building your engine.


Bob

PS: many folks envy your dilemma having to decide between building a 340 or 360 you already have!!

 

[3404spdvaliant]

340 stroked or not, or stroke the 400.

 

[moper]

450hp is doable in any build. Probably the best factory starting point is the 360. Because it has the longest stroke. That means the 450hp made will be a tthe lowest rpm. The 400 stroke is 3.38, 340 is 3.31. So 450hp will be at a higher rpm, and with components to make it that high. The stroke is the key. An aftermarket crank kit (budget) will be about $1500, then you need all the machining and the other parts. I dont think $3K will do it. Typically, a low budget mild 4" stroke engine will run about $5K. But, it makes the 450hp with running power brakes, a smooth idle, on low octane pump gas, and it makes the most torque and all the power is low in the rpm range. IMO, best of all worlds, but more pricey due to new parts needed, like heads or porting on yours, and the stoker special stuff like pistons and crank and clearancing, and the larger carb/intake... etc. a 450hp 360 will cost more than $3K also. Also keep in mind the whole package... You can build for less power, match the whole drivetrain, and be MUCH happier.