68cuda45385

Hi all. First time posting. Im new to mopars and know very lil. Im aquiring A 68 cuda fastback thats been in my parents pole barn for over 7 years and hasnt been ran in 15. Ok here it goes from what i know. It had a very hp 340 engine 727 trans. 4.56 rearend. The head gasket blew when it got parked sat for 3 years and pulled the heads, rusted 2 of the left bank cylinders. It had a steel crank, forged rods, dommed pistons. (13.5to1) compression from what i was told. Its got X? heads and J? heads one set will work one has to much compression but i dont know which ones? its got a very high lift cam .600+ and is very lopey. From what i was told and this has yet to be confermed it was sleaved and bored .060 over.. And it has like a 5k stall. Im trying to find the (cheapest) way to bring her back to life. I can get a mid 70's 360 for about 200 bucks but its all bone stock. I was told that everything off the 340 will work on the 360 with no modifications except pistons. Is this true? Like i said im a Noob. I need as much advice as possible.
Thanks in advance

mr340

Sounds like a nice start to a very expensive addiction, post up some pics. I'm going to move this to the A-body section, the cuda up to and including 69 were A-bodies

68cuda45385

Ok. see im a noob. Didn know the body style. Im gonna move her out this weekend and try to post some pics. But I realy need to Know if I can swap the 340 guts and heads to a 360 block?
Thanks

78D200

Cam and heads you can. I think the bore and maybe the strokes are different though. The 340s are very desirable motors though, why would you want to swap one out for a 360?

Silverick

78D200 is correct. If I had a choice between a 340 and a 360, I'd take the 340 without a second thought. If I had the original 340 that came in my '68 Barracuda....... there isn't a decision to be made! Keep the 340!!!
BTW....
Back in the day a drag race between a stock 340 and a stock 383.... was a real race!

1966sportfury

thats a tough one, 340's are getting harder to find, as much as i hate the 360's its not a bad choice to pull the 340 and put a 360 in. but keep the 340. if you granade a 360 its no big deal as it would be with a 340,

oilpan, crank, rods pistions will not interchange, 340/360

MReeves

Keep the 340 for sure..... They can be made into a powerhouse.....

78D200

After re-reading the first post, I would pull the 340 and rebuild it to how it was built, maybe a little smaller cam. It sounds like it was built for drag racing.

What you need to do first is decide what you want to use the car for. Drag racing, cruising, daily driver, street and strip machine..... from there, you can then figure out how to properly rebuild this car.

62Furious

I would drop in the 360 just to drive the car and rebuild the 340 for a later date and send some pics

68cuda45385

Im wanting a cruise in/street machine out of it not a drag car like it was. Like I said im gonna survey the damage to the 340 this weekend and see if its salvageable. A old mopar guy told me the 340 crank would work in the 360. I would love to save the 340 if at all possible. But money is a lil tight and i want it as good as possible yet cheap as possible. O and what cam should i get? The Mopar "purple" cam? I need some ideas.
Thanks for the replys

68cuda45385

Ok all. I yanked the engine today. I even spun it over. I also talked to the person that built the engine. Whatever you read b4 ignore. Its not sleaved (thank god) its only bored .030 over and i think it may just need honed. I cant upload pics here cause their to large. If you wanna see pics Heres my Facebook Name and i made the cuda pics public. Zak Harlow

chlngr1970

If you can build the 340, I would. Go with about 9.8:1 CR with a MP .268°/272°, .450''/.455'', 110° centerline. I'd use a Performer or RPM manifold depending on how hot you want the motor with a Holly 750 carb. Then Tune, Tune, Tune You should have a fairly powerful street mannered motor.

Next get the 727 checked out. and lose the 4.56 rear for something like a 3.55 or 3.91. 4.56 gears are a bit much for the street with a standard ( read: NOT overdrive ) transmission.

Sounds like a great project. Keep us updated, and have a great time with it

j

blue 68 gts

Yep.. My dads 340 GTS in high school would school up a 383 GTS any day of the week.

1966sportfury

thats not true, only 273,318,340. will interchange,
in order for a 340 crank to work in a 360 would take alot of expensive machine work, and a machinist who knows what they are doing with hard facing rod,