I'm in the process of building up a street/strip car and it has a 318 in it now. I'm wanting to stroke it out to raise the cid and the compression. I want to put a 4 inch stroke crank in it, but not sure on what length of rods and pistons I need. I've seen on other sites about them doing this but no one ever says if you need a shorter connecting rod or shorter pistons. Anyone have any ideas about this?

 

why build a stroked 318? go with a 360 and save some money you would have to bore a 318 90 over to reach the same 4 inch bore as a360. just throwing that out there.

 

alright the reason why i was going to use the 318 is because its what came out of the car and i don't know anywhere i can pick up a 360 for cheap and im not positive if the 360 will fit in the car, i dont know if the 360 is bigger or not.

 

they are the same mounts same bolt pattern. just may have to change the converter and harmonic balancer,, should be able to pick a complete engine for 200 or under. where are you located?

 

over in eldorado ohio

 

do you have a "pull n save" type of wrecking yard there? i can get any eny engine here for 150 if i take the 40 minutes to pull it my self. what is the car going to be used for? what is it? how much does it weigh?

 

the car is a 1986 diplomat se not sure on the weight but its going to be a street strip car, im wanting it to run low 10s high 9s somewhere in that range, and im pretty sure there isn't one of those yards around here, i haven't actually checked but i have checked on motors a couple of times and they want 300 to 350 for small blocks and thats why i wasn't going to go buy one just for the block because thats all i need, everything else will be new.

 

ahhh ic this is your first high power car right. i LOVE the dips.. the 78 dip was my first car that beat my dads "built" 440 and my frieds hard core chev 350 4bbl, and a chev 400 with duel 4s. a monty beat me cuz i droped a drive line...(cry) but i could eat fox body 5.0s all day. ok start with the rear end.. lower gears can give you up to a second in the quarter. the tranny has a lock up TQ converter. so keep it stock... save gas on the cruise. they are tuff,, 50 foot roll backs no prob, do you have the OG lean burn system?? its a big box on the air cleaner? not sure if 86 had them?

 

yeah this is my first high power build and im going to rebuild it all pretty much and im switching the trans out for a manual, hopefully a richmond 6 speed, that is if i can get a bell housing and all that for it, but it did have the lean burn on it, it crashed when i changed head gaskets, so i pulled it off and slapped a msd igniton box on it, and it wasn't too bad, but on the way home it blew a thermostat gasket and so i decided to pull the engine and just build it up. and on the note of buying a 360, machine shop price to bore and hone it to a 360, steam clean, and checked for warpage and all that will cost roughly 240, if its the same block couldn't i just bored it .090 over to give it the 4 inch bore?

 

yea you could bore it 90 over. and use it as a paper weight. you would be in the water jacket if you bored it that much. the only 318 that can be bored that much is a pre 67. wide block. 273 , 318, 340, 360 they are all the same block on the out side.. inside the 360 is a diff story. all you need is a 360 block and crank with rods, and oil pan, everything else is the same heads, cam, etc...since you are going to bore it you dont need pistions, go to a wrecking yard and tell them whats up if you talk to the right guy you could get a block and crank for a half rack of beer!? i dont have a ton o and budwiser seems to get me good deals

 

alright well im actually going to put a forged crank rods and pistons in it so i dont even need all that just the block, and i didn't think i could bore it that far but never hurts to ask, and if thats the case ill just sell my 318 then and use that money to go buy a 360

 

true never hurts to ask...okay heres the deal forged cranks for a 360 are $$$$$ since the are all after market. a stock cast 360 crank is STRONG becouse it has a lot of meat on it. no need to get a forged crank for a 360 unless you want to turn 10grand all day, all i would do with the crank is balance it and get the counter weights cut down so it can rev quick.

 

alright i might have found an aftermarket crank though for about 300 new so i may go that route.

 

ill probably be spending around 5 gs

 

Why put $5000 into a junkyard 360 block ?? If you are serious about running in the 9s with a small block diplomat, you're going to need an aftermarket block, PERIOD! to make enough power (I'm guessing around 800+ but probably a lot more,) to push a heavy street car that fast, a 30 year old production block,and a 300 dollar crank, Ain't gonna do it. take a look around at your local dragstrip, & look at the hardware inside the 9 second cars! I know, I probably sound like a total jerk, but it take a HELL of a street car to run nines !........Unless you're talking 1/8th mile, then disregard everything i just said.

 

actually ive done the research and i DON'T NEED an aftermarket block, yes it would be nice but its not a must. the crank i am looking at will handle up to 600 horse, so i doubt i will be able to use that crank so that is out of the picture. but other then that if i build the engine i plan on, and if my figuring is right, it will be about a high nine, low ten second car, and not in the 1/8th mile.

 

A friend of mine in the local Mopar club has a 70 Dart street car, with a 410 cube stroker small block, he's got a Mopar Performance Race block, running 13.5 to 1 compression,(race fuel ) professionally race ported Indy heads, a huge solid roller cam (approx .690 lift) And all the other supporting fuel system,transmission, chassis, and rear axle mods, his car runs 10.70s @ 127 mph in the quarter, & is pretty light at around 2800 lbs. he's got just about 5K in the cylinder heads alone. To run a second or so faster in the quarter, in a heavier car, you will need to be making 200-300 MORE horsepower than my friends Dart, you can get there with nitrous, a supercharger, or a big turbo. That Diplomat is going to be insane! good luck!

 

sounds like a bad *** dart, and i plan to put race heads ported and polished on there, and a few other things thats going to add some power, and i may need to get an aftermarket block in the long run, but im going to try and lighten the car as much as i can, i have a few ideas for doing that but i dont know if it will be enough, i will just have to find out as i build it

 

well im not doing a 318 any more i just bought a 360 that im going to be using.

 

yeah i got the 360 for a decent price so i did the smart thing