0ver Boring a LA 318, how much is poss for more cubes ?

[Dodgy Dick]

I welcome all your suggestions, I am trying to plan/work out a budget performance build. How far can you safely over bore the LA 318. I would love to simply get my hands on a 340 or even a short block but alas they are as scarce here as kangaroos in the South Pole!
As I'm in OZ we do not have the scope of performance parts availability as you Guys n Gals are lucky to have in the States. Importing parts is killed by shipping, often costing more than the actual part itself!
Stroker kits are an option but Boy!! their "bluddy" expensive here!!
Dodgy Dick

 

[Turboomni]

What rear end ratio is your 318 pushing on at the moment?

 

[Davea Lux]

I welcome all your suggestions, I am trying to plan/work out a budget performance build. How far can you safely over bore the LA 318. I would love to simply get my hands on a 340 or even a short block but alas they are as scarce here as kangaroos in the South Pole!
As I'm in OZ we do not have the scope of performance parts availability as you Guys n Gals are lucky to have in the States. Importing parts is killed by shipping, often costing more than the actual part itself!
Stroker kits are an option but Boy!! their "bluddy" expensive here!!
Dodgy Dick

The recommended max over bore is .060 which is not enough to help much with performance. You can have larger repair liners installed, but this weakens the block.
Might be better off finding a 360 and going to after market heads and high compression pistons if you are really set on staying with a small block configured engine.

 

[Dana]

There are plenty of 318's running around with stock bore 340 pistons in them. The rumor is a block with 4 motor mount ears on each side is most likely capable of such overbore.

 

[Dodgy Dick]

G'Day Dana, Sorry for my ignorance but can you please explain so I can check mine or other 2nd hand 318 offerings!!
Wouldn't it be great if somebody coming to OZ could put one in their carry on briefcase for me,.... only joking !!

 

[Dana]

OK sir, some of the older 318's ( not sure of the years) had 4 motor mount holes cast onto the side of the block. Later, all small blocks had 3. The 4 holers are said to be able to go 4.040. Of coarse sonic checking would be a must.

 

[commando1]

If you looking for more power by having more cubic inches, boring won't be the answer.

 

[Dodgy Dick]

I'm in you hands, tell which way to go,remember down under I dont have the same resourced as you in the Us of A.

 

[Dodgy Dick]

Hey Turbo **%$# Mni I think my diff ratio is 3.23

 

[MoparBrew]

yeah...I don't think you'll be going too fast with a 318 in a C Body. It's just a power to weight thing. A good 318 in a proper state of tune will run great and keep up with traffic, that's all I would hope for.

 

[Turboomni]

You could go to a 3.55 if you don't do alot of highway driving.

 

[detmatt]

I think .030 on a 440 is equivalent to adding 6 cu. in..

 

[heyoldguy]

detmatt is correct. A .030" overbore in a 440 is 446 cubic inches and a .030" overbore in a 318 is 323 cubic inches. Just adding 5 cubic inches won't change much.

 

[BeatersRus]

if you are determined to stick with the small bock.
we are currently looking at building 2 magnum motors and a la 318.
one of my friends suggested an enginequest set of iron heads,
they can come with magnum OR La intake config.

EngineQuest, Chrysler 318/360, Magnum w/LA Bolt Pattern, 67-89, 172cc/62cc, Straight Plug, Bare, Each - Competition Products

heres where we got stuck on just a basic get it running so we can use it deal.
it was the total pricing and performance.

example 1=
360 magnum out of truck,cost nothing except labor to remove from scrap vehicle.
new 4bbl intake 300 bucks if you can find one cheap.
new fuel pressure regulator,and electric fuel pump setup for car,With lines,150.
new car oil pan and pickup,gaskets and such 225 bucks.
new enginequest heads 730 bucks for a set,<< Bare.
now we need new rockers too and we havent even touched the cam.

example 2 = 318 la motor out of car.
4 bbl intake less than a 100 bucks usually.
timing chain gasket set and new camset all in around 350 tops.
but,youll need to throw a Big stick in there to make lumpy idle power that you could have gotten much smoother from a magnum 318 or 360 plus the heads are better on the magnums.

so,you need a really good plan,before you start any build.

 

[Carmine]

My suggestion to you long ago was to import something useful (like a truck or van) that came with a 360 and other goodies from the US. Even better, have somebody build/tune said vehcile while in the US with the latest and greatest heads, cam, etc.

Swap in your 318 and sell for the same $ because nobody will care about speed in a dodgie 'ol yank pick up. So long as it can haul kangaroo food to the outback, it has a purpose.

 

[Turboomni]

What about a small fan belt powered supercharger with 5 pounds boost or so?

 

[Bart]

You can get a stroker kit for the 318... Also I run small blocks in two of our C bodies. They can make more than acceptable power. Shoot for 9:1 compression, or a touch more. Get a cam in the 260-268 range (the 340 cam is a great fit!), and get some cheap Dodge Dakota truck headers. Add 4-bbl intake and 600 cfm carb, and. 2200-2400 stall converter, and you a a very happy camper. That should be very reasonable, even down under!

 

[Alchemi]

Hey mate, where in QLD are ya?
Most likely i can point you in a good direction to a 360 block if thats the way you want to go - not a bad option mated to a 518 OD trans
The latest trend im seeing here is to stroke em out to 408
Define budget? The dollar is strong this week... and i can give you some good pointers on freight
Have you considered a 5.7 swap from a 300c?
Someone locally has a m90 supercharger setup for a slant 6 for sale lols

 

[Dodgy Dick]

G'Day Alchemi, Maaaate! thanks for your help, I am located 10K out of Canungra about 3/4 hour west of the gold coast. I dont want to go too overboard, wanna keep my 69 Phoenix looking pretty standard and only a limited budget, if I spend too much I'll have to pay for a divorce too!!
R

 

[Alchemi]

you have a PM