360 cheap-o build

[D&R Const]

I scored a smoking deal on a 360 today. Standard bore, no ridge. crank looks like it will only need a polish up. I am going to get some arp rod bolts and main bolts and do an other wise stock bottom end "throw together". May look into KB107 pistons for something better than stock, but still affordable.

I will post more pics once I get a new phone. I dropped my phone on a rock today and it magically only broke my camera lens.

I am not sure what brand of cam I received with the deal, but I am going to run the part numbers tomorrow. Heads are "596" heads that have 2.02/1.60 valves installed. I am going to take a couple of valves out and see if they properly opened up the throat to the larger valve size. Hoping to do all this rebuild and get it in the car for less than $1K running. Looking forward to pulling the 150HP 318 out ASAP.

 

[318willrun]

Let the fun begin

 

[D&R Const]

Let the fun begin

Thanks! Really excited about this one. Also excited to be able to preserve the stock 318. It sure would be an upgrade for our 1966 Dart 4dr that has a very tired and smoking slant 6

 

[Abodybomber]

Enjoy.... 360 builds are FUN... Keep it simple,cheap,& attention to details...You will ,have a winner...

 

[rumblefish360]

Is that 1K in parts of 1K in total?

No matter the cam choice, I suggest that the whole package be purchased with the matching parts. It makes things simple and complete in one shot, no guessing.

 

[JBurch]

New rod bolts and main studs are moving away from your title of "360 cheap-o build"........have the big ends of the rods checked, if they are in spec, all is good......main studs won't buy you anything at the level of build you seem to be heading for ( I didn't use studs in my 360 race motor ).......money not spent on the previous can be spent on a good balance job.......with KB 107's you might slide into an internal balance reasonably

What ever you do, good luck.

 

[D&R Const]

New rod bolts and main studs are moving away from your title of "360 cheap-o build"........have the big ends of the rods checked, if they are in spec, all is good......main studs won't buy you anything at the level of build you seem to be heading for ( I didn't use studs in my 360 race motor ).......money not spent on the previous can be spent on a good balance job.......with KB 107's you might slide into an internal balance reasonably

What ever you do, good luck.

No plan on using studs on the mains, rather just better bolts. Sorry if I was unclear. Ia m leaning towards getting better hardware for peace of mind. I don't have any plans to do anything exotic with this engine as it is not the long term plan for the car.

I found the cam specs for the cam that was included in the deal. The heads have a single spring with damper from Engle as well.

Engle Cam
EP18
Street performance, good idle. Lightly modified IN .458” 260° .305” 216° 113°
engines. Powerband 1500-5500 approx.
216*/216*
.458"/.458"
113* lobe center

Certainly not a big cam, but an upgrade over what I have now with the stock 318 2bbl.

 

[rumblefish360]

That is a great general purpose 4bbl. cam that will certainly increase power noticeably over a standard 4bbl. Engine set up.

 

[D&R Const]

That is a great general purpose 4bbl. cam that will certainly increase power noticeably over a standard 4bbl. Engine set up.

Great. I imagine that this cam would safely clear a stock replacement type piston with no valve relief. I hope, but will check just to be sure.

I dropped the heads off to a buddy of mine who has a head porting service in the San Antonio area. We are going to trade some slave labor for head work. He is going to gasket match, pocket port, and get rid of the smog hump in the exhaust port. He has a flow bench, looking forward to his results.

 

[autoxcuda]

Leave the stock main bolts. No gains, not even piece of mind.

What are the dimensions/measurements and dish of the Pistons that are in it now?

9:1 compression or close would be fine for that setup and run pump gas.

Only reason to put new Pistons would be for compression change. Measure what you have and see if thin head gaskets and mild head milling would get you near 9:1.

I'd be shooting for $400-500 in putting that long block back together.

 

[D&R Const]

Leave the stock main bolts. No gains, not even piece of mind.

What are the dimensions/measurements and dish of the Pistons that are in it now?

9:1 compression or close would be fine for that setup and run pump gas.

Only reason to put new Pistons would be for compression change. Measure what you have and see if thin head gaskets and mild head milling would get you near 9:1.

I'd be shooting for $400-500 in putting that long block back together.

Good advice. Feeling more inclined not to spend anything unnecessary on this bottom end, but rod bolts are affordable enough that I won't feel guilty replacing them. I will measure the piston depth this week, they are about 1/4 mile from the deck at TDC.

 

[sireland67]

Keep in mind I had to re-balance the bottom end when using the KB 107's it may save you money to check into different piston options that weigh the same as the stock piston/pins.

 

[autoxcuda]

Keep in mind I had to re-balance the bottom end when using the KB 107's it may save you money to check into different piston options that weigh the same as the stock piston/pins.

And that's the beginning of a snowball.

Rings, bearings, hand hone, oil pump, pickup screen, clean water passages meticulously. And see what you can do to surface heads or use thin head gaskets.

Maybe get that Edelbrock RPM intake for sale here that's got the head bolt hole already hacked for decked heads. Not pretty but should work. IMHO, worth $150 shipped.

Then spend money on a decent carb if don't have one.

Search around for a good priced less desirable HP Hi-flo 73-76 340-360 manifolds. Or a magnum right side you can grind out to 2 1/2" yourself. Wouldn't bother unless you kept the manifolds under $250.

 

[D&R Const]

Not likely to use on this engine, but was curious if anyone has any personal experience with the crane 1.6 ductile iron rocker arms. Any issues with the added ratio? Do the pushrod tubes need work to clear?

 

[nm9stheham]

Keep in mind I had to re-balance the bottom end when using the KB 107's it may save you money to check into different piston options that weigh the same as the stock piston/pins.

The above is correct.... the KB's are about 110 grams lighter with the pins than stock, and will call for a rebalance. H116CP's are close to the KB's Iedit to add: in terms of compression height, valve reliefs, etc.) and piston+pin weight is very close to the stock weights: i.e., no re-balance.

Either piston will push your Static CR up into the mid to upper 9's; you can select the head gasket to tune it to the level you want/need. Speaking of which: What are you going to be doing with this engine? Street? Strip? Towing? Paperweight? LOL

 

[D&R Const]

The above is correct.... the KB's are about 110 grams lighter with the pins than stock, and will call for a rebalance. H116CP's are close to the KB's and piston+pin weight is very close to the stock weights: i.e., no re-balance.

Either piston will push your Static CR up into the mid to upper 9's; you can select the head gasket to tune it to the level you want/need. Speaking of which: What are you going to be doing with this engine? Street? Strip? Towing? Paperweight? LOL

The above is correct.... the KB's are about 110 grams lighter with the pins than stock, and will call for a rebalance. H116CP's are close to the KB's and piston+pin weight is very close to the stock weights: i.e., no re-balance.

Either piston will push your Static CR up into the mid to upper 9's; you can select the head gasket to tune it to the level you want/need. Speaking of which: What are you going to be doing with this engine? Street? Strip? Towing? Paperweight? LOL

Thanks for the advice on the pistons. I will look into that. Those are the same pistons I believe went into my Dad's 360 back in 2001ish. Never had any problems.

Speaking of balance. . . I know its good but I surely don't understand the process whatsoever. Any experts here care to explain? I grasp that the rods and pistons are all touched up so that they weigh the same, but what exactly is done to the crank?

This engine will be going in my 1973 Duster as a somewhat temporary engine until I can afford to build a W2'd 360. It will also help me learn the car at the strip, this is going to be my very first muscle car as an adult. My last experience with any Mopar was 15yrs ago when I was 16, and even then, Dad was smart enough not to let a kid drive his 1970 Challenger much. The very long tern goal is to put this engine into our 1966 Dart 4dr in place of the smoking slant 6 that is in there now, when my daughter is old enough to drive (she is only a year and a half right now, hehe)

 

[nm9stheham]

The crank's counterweights are there to counter balance the weights of the pistons, rods, pins, etc. that are flying around them. These counterweights have to be of the proper weight to do that. So in the balance process, the weights of the crank counterweights are modified.

They don't actually use the pistons, rods, etc. flying around the crank in the actual balance process. A 'bobweight' is computed and that is what is actually physically attached the crank throws (rod journals) in the balance process. The computation of the bobweight is just math, based on carefully measured weights of the piston, pin, rings, locks, rod bearing, and both the big end and small end weights of the rods weighed separately. An assumption is made on how the rods' end weights distribute into the reciprocating and rotating weight components; 50% is the usual resulting math factor that gets plugged into the formula. You can find that bobweight formula on the Eagle site and elsewhere.

With the bobweights attached, the crank is spun on a machine that tells the operator what need to be added or removed where and on what crank counterweights. (Some weight is also removed at the factory inside of the outer crank throws in the case of the 340.)

For a 360's and the '73 340, part of the balance in the crank counterweights is contained in the damper and another part in the flex plate or TC, or in the flywheel. These are known as 'external balanced' motors, which is a misnomer, as it really is a 'partially externally balanced" engine design. So for those engine, you have to supply these external crank parts to the shop for the balance work too.

As an aside, Most folks will just hand all of this off the shop. If you are good at measuring and math, you can do all this bobweight computation. With well known rod and pistons weight numbers, I have done it myself and just given the bobweight number to the shop to work with; it saves considerable $$ on the balance work.

That is one beauty of good aftermarket rods; they come already weight matched AND with the big and small end weights already measured for you, and with weight matched pistons like KB's or the good SpeedPro's, you can compute the bobweight, let the shop do just the crank balance, and match up the pistons and rods yourself with a scale. That trick pays for a good portion of the new rods. With new lightweight KB pistons, I'd seriously look at this trick (but only IF you are comfortable with the math!) as a way to pay for a large portion of new lighter rods like SCAT's. Much weight and stress are taken off the crank, so that is another bonus, and makes the rebalance $$ spent even more productive if you are going to hammer on your engine at all.

BTW your dad sounds too smart or your own good ....LOL