boring my 318

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Knifeing the crank at this level is not really worth the effort at this level of performance.

When you order the pistons and spec a 9.0-1 ratio, the main question you'll need to answer and know is how many cc's the head has. This way they'll know what piston to give you.
You'll want the ratio to be between 9.0-1 and 9.5-1 for iron heads. (Plus 1 point for aluminum heads.)
 
Keith Black makes a piston off the shelf that will work wit a 360 strock crank... You will have to turn the main journals down .300 to fit the 318 block...This will give you the 3.580 stroke...Might as well turn the rod journals to 2.100 and use a chevy 6.125 rod (if you are buying aftermarket rods...Chevy's are cheaper)...Less rotating weight revs faster...This will make you a 349 cu. in. motor
 
Rumblefish, sent you a pm. Mike
 
Dusterboy, What background do you have in engines? The reason I ask is there is much more than ordering new pistons or turning a crank and just sticking it together. That is a recipe for spending money many more times than you have to. I'm assuming you dont have the unlimited budget. What do you want out of your car? How much money do you honestly have to play with? What have you already done to the car?

In order to swap strokes, you also need to replace pistons and rebalance the assembly. In order to replace pistons, you need to rebore the block, and re-hone, and rebalance. You will also need new rod and main bearings, and now ring, plus cam bearings and block hardware, plus completely disasemble the engine. Basically, a rebuild. The compression is a big part of power, but you cna make power in other ways without spending on a rebuild. SO what do you really want to do?
 
The 318 is a fun little motor that responds well to basic bolt ons. I'd go with 302 heads with a little bowl work, a windage tray , clutch fan, performer intake, headers, x pipe, good free flowing mufflers and exhaust, and a cam matched for your setup.

One thing that I haven't seen posted is what gears are you running?
When I was in high School I had a 318 in a 71 Duster with basic bolt ons and 3.91 posi, it was a great little combo as long as I didn't do much freeway driving, if you do 3.55's might be better. Gears make a huge difference, so if your running some freeway gears your car is always going to feel kinda sluggish around town.

Personally I wouldn't waste money on stroking a 318 though, if you get to that point just go grab a 360.
Good luck with it.
 
Mike, got your PM.

Sorry if I step on your toes. No insult ment to Mike or anyone.
 
I was thinking of a fella I just got off the phone with that has used a 360 crank with 318 pistons.
BJR, stage is yours.
 
Heres 302 head info.
4323302 1985-1987 318 2bbl swirlport 1.78" 1.50" 56cc - 65cc

I was also told that they were on 318s up until 1991 but I can't verify that info. Mike
 
ValiantMike said:
Heres 302 head info.
4323302 1985-1987 318 2bbl swirlport 1.78" 1.50" 56cc - 65cc

I was also told that they were on 318s up until 1991 but I can't verify that info. Mike
Click to expand...
i do belive that this correct. 1991 is the last year for the 302 cast. the ones i have are 1988. i think the magnum heads took over after 1991....
 
rumblefish360 said:
I was thinking of a fella I just got off the phone with that has used a 360 crank with 318 pistons.
BJR, stage is yours.
Click to expand...


Rumble,
I don't want to hijack this thread so I'll start a new one with what we talked about.
 
moper said:
Dusterboy, What background do you have in engines? The reason I ask is there is much more than ordering new pistons or turning a crank and just sticking it together. That is a recipe for spending money many more times than you have to. I'm assuming you dont have the unlimited budget. What do you want out of your car? How much money do you honestly have to play with? What have you already done to the car?

In order to swap strokes, you also need to replace pistons and rebalance the assembly. In order to replace pistons, you need to rebore the block, and re-hone, and rebalance. You will also need new rod and main bearings, and now ring, plus cam bearings and block hardware, plus completely disasemble the engine. Basically, a rebuild. The compression is a big part of power, but you cna make power in other ways without spending on a rebuild. SO what do you really want to do?
Click to expand...


well what i do with motors mostly is just tune and repair not really a power making situation.
I want the car to make around 300-350whp nothing big maybe 13secs
Right now the car has a streetmaster intake eldbrock and a 4 barrel carb and flowmasters that came with the car when i bought it

I really want to kep it 318 becasue its orginal and i want to make it a sleeper and if i restore it with the motor built i want everyhting to be jsut like it came besides the motor being built
 
I think for that level, you will want to look into using a360. Then it's basically just a bolt in a cam and you're there. If budget is not very large. Get a running 360, toss a cam in it, buy the B&M flexplate, and bolt it in. Could prob do it for less than $1200.
 
That's not too hard. Some key things: You want to here it run. This can be done easy even with an engine sitting on it's pan with a trans still attached. Trucks (3/4 ton or bigger) will have the best chance of finding one. If you can locate a good mid 70s C body, they may have one too. Along with some Cordobas and 300 from the 70s. Get it complete and running, preferably from a pass car so you dont have to swap pans. I would guess somewhere between $500 and $800 would be more than enough for one. I know of 2 within 1/2 hr drive that are $400.
 
if i get 302 heads for the 318 do i have to use 86-88 headers and intake manifold or what do i do thanks
 
How long till that book(s) come in for you?

The issue with intakes is on Magnum engines. Exhaust manifolds and headser are not an issue.
 
magnum heads are where parts fitting become a problem. basiclly all small block moper parts are interchangeable with each other. the magnum heads will require some work to make them work, so if you are not useing them everything is cake....
 
i got the books thats why im asking but i dident see a part saying anyhting bout needing different parts i was jw so are you saying that i cna bolt them right on and bot a regular intake and headers on or what?

and if i get 9.1 compression pistons what will the compression be with these heads
 
i don't quite know what you are saying, but if you are asking again if you can just bolt the parts to headers or different intake the answer is yes. as long as it is not a part for a magnum head then any small block part will interchange. compression will pick up anywhere from 1/2 to 3/4 point useing the 302 casting heads.
 
DusterBoy15 said:
i got the books thats why im asking but i dident see a part saying anyhting bout needing different parts i was jw so are you saying that i cna bolt them right on and bot a regular intake and headers on or what?

and if i get 9.1 compression pistons what will the compression be with these heads
Click to expand...

Hard to follow the post.

What's "jw" and what do you mean by "or what?" it shows up alot.

If you use Magnum heads, you'll need ethier a Magnum intake or have the Mangum heas redrilled to accept an older "LA" intake. The exhaust will bolt up. Port alignment may not be the best since header companys use the old standard design exhaust port pattern.

Also, to use Magnum heads on a "LA" block, you'll need to use AMC lifters and different pushrods. These can be had at the dealer/MoPar Performance.

Does that answer the "Or what?" ? (Ha ha ha, joking.)

On compresion, you'll need to know how far down the piston is in the hole or know the piston height. There are calculators on line that you can use to determin the ratio.
Try KB pistons. I had a link that is currently failing. Grrrrrrr Anybody have a KB link handy?
 
o sorry jw means jsut wondering and or what means like if not what not what im saying then when what do you me

how about.. what would i have to do to make 360 heads work and is there big valve and small valve heads and what would my compression be thanks
 
o sorry jw means jsut wondering and or what means like if not what not what im saying then when what do you me
Click to expand...
LOL, OK then. (It's brain twisting sometimes after the midnight tour.)

All 360 heads should be small valved @ 1.88. Theres some that say they also came with 2.02 intake valves, but I have never seen it myself. That doesn't mean it doesn't exisit.
On a 318, if you have 360 heads, and you want to use them, it'll ok to do. It is a good on the cheap upgrade. Ethier ported 302's (late 318 heads) or a Magnum head swap would be more powerful than 360 heads with any valve.

Again, on compresion, you'll need to surply some info. exact ratio depends on this. This question is basicly un answerable unless you have done it and/or measured the specs needed to know. You can ask this question 50 different ways, the answer is allways going to be the same.

In theroy, he he he, if the 318 is an 8.5-1 engine, with a head cc chamber of 65 cc's and you swap on a 360 head with 75 cc's, you drop the ratio from 8.5-1 down to 7.73-1. With this ratio, you now can use Yak urine to power the car.

In order to make the 360 heads work is a milling of the deck to get the number of cc's down to the 318 head or less. And then the heads start to make power close to what the stock heads do.

Actually, IMO, you would be better off stealing the 360 valves and installing them in the 318 head and doing a bowl porting and port window enlargement for better torque and HP. The skinnier port and general smaller sized port will have better velocity and keep the engine from getting a muddy bottom end.

The 360 head can make more power if built for it. But your hard pressed to make use of the larger head port and valve size on a 318.

What books did you get/have now?
 
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