340 rebuild

[Nate70]

I have a 70 challenger with 340 and 727 all matching numbers.  Had a terrible knocking noise when I started the motor.   So I quit driving it once I heard the noise.  It sat for 2 months, I moved got settled in and found a machine shop who will work with me in rebuilding the engine(letting me do the work in a corner of the shop and if I have questions they will help, saving me money). 

Anyway, I tore the engine completely down, only to find that the noise was a broken lifter.  I have limited knowledge with the inter works of the motor, so I tore it down not knowing when to stop.

With all that it has been bored .030 over and had a hugh cam in it(0233 thats the only marking I can find).  Double roller timing cain.  With Edelbrock 750 carb(4 bbl) and proformer rpm intake.  Have the origanl carb but no intake.  MSD 6A ignition. The torque converter stall is 3400.

The questions I have are:

What should I replace? 

I am replacing the cam with a milder one, but which one?

I am gonna replace the torque converter, but which one, what stall?

The block looks like it has a few miles on it minuis becides the #7 pistion (broken lifter) it is black with heavy build-up on it.  The cylinders still show the cross hatch and are not tapered.  The other pistions are slightly burnt a nice brownish.

I bought this car to drive and I did drive it everyday untill the noise.  I want the car to drive, and be dependable. 

I was going to have the heads rebuilt no mater what.  I know nothing about heads, however I am 90% sure they are not aluminum.

I know all the gaskets need replaced, since I ripped all but 2, and all the bearings too.

Any and all help is greatly appreciated.

[Nate70]

Also have hooker headers.  I hate them, any recomendations?

Looking to spend no more then $4000 right now.

Thank you again.

[dodge freak 2]

$4000, wow, you could get all new forged pistons and crank reground, etc etc.

You need to find a honest machine shop, one who will check everything and just replace whats needed. By not looking and measuring everything, its just a guess. Sounds like the pistons might be just fine. You can always just changed 1 too.

Whats gears do you have in back, then we can pick a cam, unless you know you want a smooth idle, then I say keep it under 216 @ .050 on a 112 lobe center

[Nate70]

again, not sure but think its 3.71 by rough measurment.  not posi either, will change problly next year.  found out by doing research that I have x heads if that helps.

And the machine shop guy said he want to clean, measure and flux the block and heads. to be on the safe side.  He said that if it doesnt need replacing he wont replace it where as the other shop started spoting off conponets to replace without seeing anything.

He will aslo check the balance of the crank and see what else needs done.  I trust the guy, he is honest and a friend had his engine built the same way from him.

His only down fall is he isnt a dodge guy, likes fords.  So I fugure buy asking around here I could get some dodge input and bounce it off what he suggests.  To see if he really understands the engine or just guessing.

[tactransman]

I believe this is the specs on your camshaft. 

http://store.summitracing.com/partdetail.asp?part=DCC%2D4120233&autoview=sku


Original stall converter could be OK,depends on what you want to do with the car.

[Chryco Psycho]

I would use a Lunati VooDOo or Engle grind , not sure exactly what you want fromt he engine though so I cannot pick a grind
 typically I use 225-240 *@.050  cams on the street , you need to match the convertert ot the cam so if the cam starts making power at 1600 rpm you need approx 2000 stall , if the cam starts at 2000 get a 2400 stall converter
 I can only suggest TTi headers , they fit & do not go under the steering leaving a ton of ground clearance , I cannot find another header like this

[Nate70]

Thanks again for all the input. 

As far as the engine goes, I am like anyone else: "The biggest bang for the buck."  I want the car reliable but at the same time I want to beef it up as much as possible.  I just dont want to go extreem.  Dont want to have to keep the revs up to make power.  A reliable but fast street car. and a daliy driver.

[74 340 4speed]

I believe this is the specs on your camshaft.  http://store.summitracing.com/partdetail.asp?part=DCC%2D4120233&autoview=skuOriginal stall converter could be OK,depends on what you want to do with the car.

I have that cam, and its a nasty one.   I have my idle set at 1100, and it lopes like a s.o.b.   With an auto, I wouldn't have that radical of a cam, unless I was going to plan on having an 1/8 or 1/4 mile drag car.  I would put something in it in the mid 230 to 240 duration range on a 110-112 LSA and use your current stall converter.  Since you you have a decent sized budget, I would really consider getting a set of better heads(aluminum).  If you are able to reuse your rotating assembly, then I would definately get a set.  The gear you have now would be perfect for all around performance if it is in the 3.55-3.91 range.  I assume it is by your previous post.  Don't all of the earlier 340s, 68-71 have forged rotating assemblies from the factory?  The pistons would be questionable in his build but if the other pieces are stock, they are forged, right?

[go-fish]

The power is in the heads! With your budget I would think you could spring for some Edelbrocks or good worked over EQ's.

[Nate70]

here is a look at the top of the pistons.

this is the cam I am thinking about:

http://store.summitracing.com/partdetail.asp?part=LUN%2D60403LK&autoview=sku

do I need to chang the stall or not,  I have no bottom end(NONE) and it is embarassing driving a muscle car with no torque.

and any ideas on where to find aluminum heads for the 340 all I can find are for the 440.

[go-fish]

You can get Edelbrock heads alot of places. www.hughesengines.com has really ood cnc porting programs if you want something more than out of the box Eddy's and Mancini Racing sells Indy Cylinder Head prepped Edelbrocks. These are basically the same thing as T/A and AAR style heads. These are not shaft monted rockers and they actually utilize a Indy Big Block rocker. http://chucker54.stores.yahoo.net/inedenalhe.html -IndyBrocks

[go-fish]

For out of the box Eddy's, just go to Scummitracing or any of the smaller guys I mentioned. Also you can try Moparts.com's for sale section. Alot of parts go through there.

[Nate70]

summit racing doesnt have heads for the 340 and the other oneshughes engine say their heads are for the 360 so I dont know if they will fit?

[go-fish]

They will fit. Best thing to do is call Hughes. Talk to Dave or Kevin, they do not try to pressure sell. While they do need to sell parts to stay in business they do not lie to sell parts and trully want to give you the best component for your needs.

[Nate70]

if I change the heads will I have to change the intake?