Opinions / Advice On Possible 318 Build

[Road_Runner]

OK, I'm seriously thinking about going for a strong but streetable build of the Barracuda's original 318 instead of swapping engines like I originally planned.  The main reason is that I've grown to appreciate how stock it is for a 39 year old car.  So here's what I'm thinking: 318 block, either stock or 302 heads, LD4B or LD340 intake depending on port-size of heads, 650 Edelbrock Thunder carb, either stock 318, stock 340 or TA/AAR style iron exhaust manifolds, and looking for piston & cam recommendations.  Car has PS, PB, and AC so engine can't be too wild needing decent vacuum, etc.  Also has stock 904 trans & 2.70 8.75 rear. but I'm thinking about changing to a 3.23 gear and maybe a higher stall torque converter after I see how the engine does with whats there now.

So what is a doable HP/TQ target for such an engine?  350-375 HP? similar TQ? Just trying to decide how quick the Barracuda would be with this kind of build, would it leave me wanting more when a newer Camaro/Mustang/Challenger/Honda pulls up alongside.  My other option would be a 340 based build, but would still want it streetable.  One thing I haven't really thought about for the 318 is a stroker crank, but have thought of doing that with a 340.

So what do you guys think, build the 318 or is the 340 really going to make that big a difference? Are the different exhaust manifolds going to make a big difference on this engine?  I'd like for it to 'appear' mostly stock so that's why I'm staying away from headers, etc.  Any & all advice is appreciated.

Thanks in advance, Jim

[GranCuda1970]

imho Build the 340, more oooomph!!!  Dont get me wrong 318's are good engines but the 340 is a winding performer.

[Chryco Psycho]

we did a similar build for a collectable Duster . ported the heads , used a Holley 570 Avenger , 340 exhaust manifolds
 I cannot remember the piston # but it had decent compression & a Lunati VooDoo cam , ran well & made decent power , but nothing near the 375 hp a 440 made stock , the 318 just doesn't make torque .
 You could drop in a stroker crank this would add significant tq & I would recommend the 302 or 308 heads , we gained 41 RWHP just swaping 308 onto a 340 with X heads

[Road_Runner]

we did a similar build for a collectable Duster . ported the heads , used a Holley 570 Avenger , 340 exhaust manifolds
 I cannot remember the piston # but it had decent compression & a Lunati VooDoo cam , ran well & made decent power , but nothing near the 375 hp a 440 made stock , the 318 just doesn't make torque .
 You could drop in a stroker crank this would add significant tq & I would recommend the 302 or 308 heads , we gained 41 RWHP just swaping 308 onto a 340 with X heads

Would the 340 block with the same 302 heads make that big of a difference or would it still need the stroker crank to make decent HP/TQ?  I know the 340 has a bigger bore which unshrouds the valves, what valve sizes would you use for 302 heads and do these have 340 or smaller 318 ports?  What work would you do to the 302 heads for this type of build?

Thanks, Jim

[Chryco Psycho]

the 340 uses the same crank so the torque will be similar to the 340 although the 340 will breath better , I would use 308 casting for sure on the 340 , you can use the same valves as the X/J heads in the 308 head , I would definatly port the heads as well . The 302 casting has the small 318 port , the 308 uses the larger 340/360 port .

[Road_Runner]

the 340 uses the same crank so the torque will be similar to the 340 although the 340 will breath better , I would use 308 casting for sure on the 340 , you can use the same valves as the X/J heads in the 308 head , I would definatly port the heads as well . The 302 casting has the small 318 port , the 308 uses the larger 340/360 port .

Good info, thanks.  Of course I already have a set of the 302 heads!  I'm going to have a heck of a yard sale whenever I settle on a direction with these cars.  So given my goals would you stroke the 340?  And are the Indy/RHS LA heads worth the price difference?  I'd have to go find a set of 308 heads and have them gone over if I go that route.  Any comments on the power difference between 73 340 exhaust manifolds vs. the TA/AAR versions?  Are either going to kill my HP/TQ vs. headers? 

Thanks again, Jim

[Chryco Psycho]

Actually the magnum truck exhaust manifolds are cheap & will make more power than either of the 340 castings LOL . Check out Bandt new thread , he gained close to 30% in power with head & cam change . So yes good heads like the RHS are worth the $$
 If you do the 318 use the 302 castings , get a good cam profile like a Lunati VooDoo , make close to 10:1 compression & you should get a strong running engine out of it

[Road_Runner]

Actually the magnum truck exhaust manifolds are cheap & will make more power than either of the 340 castings LOL . Check out Bandt new thread , he gained close to 30% in power with head & cam change . So yes good heads like the RHS are worth the $$
 If you do the 318 use the 302 castings , get a good cam profile like a Lunati VooDoo , make close to 10:1 compression & you should get a strong running engine out of it

Sounds like I've got a couple of good options.  I think I'm going to go ahead and put the LD4B & Eddy carb on the 318 and see how much that helps and go from there.  I'm building the Roadrunner for top HP, the Barracuda just needs to get out of its own way and not embarass itself against other normal street cars. Thanks for the help.

Later, Jim