Stroke a 318

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hwy2

hwy2

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I have a 318. I made a huge mistake and left a rag in the motor and started it up. Needless to stay, it tore the rag up and it went through my motor. I found out because I changed or upgraded the distributor. Since I have to take my block apart, now to blow out all the oil passage lines, I would like to put in a 4 inch crank, is there anything special I have to do to put in a 4 inch crank? Any helpful? Suggestions would be greatly appreciated. I found a lightweight crankshaft on Summit racing for an internally balanced motor. What parts will I need to complete this?
 
hwy2 said:
I have a 318. I made a huge mistake and left a rag in the motor and started it up. Needless to stay, it tore the rag up and it went through my motor. I found out because I changed or upgraded the distributor. Since I have to take my block apart, now to blow out all the oil passage lines, I would like to put in a 4 inch crank, is there anything special I have to do to put in a 4 inch crank? Any helpful? Suggestions would be greatly appreciated. I found a lightweight crankshaft on Summit racing for an internally balanced motor. What parts will I need to complete this?
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You do need special pistons to go with that crank.
 
honestly, if you're going to build a stroked 318, I'd start with an '85-91 block. they have factory roller cams, 302 heads. the roller cam is the biggie. you can get it reground, or get a roller cam and reuse the stock roller lifters at a much lower cost than the retrofit roller lifters.

putting a stroker crank in requires at a minimum new crank, pistons, and block clearancing if using stock rods, IIRC.

any 318's stock heads will be way undersized as far as flow to have any power above about 4k RPM.
 
that said, a 4" stroke 318 (~390 CID .030 over) with a hydraulic roller with about .55" lift and [email protected] duration, magnum or edelbrock heads, headers, an RPM air gap and a 750cfm carb should be a really great, streetable 400+HP/400+lb ft torque motor.
 
hwy2 said:
I have a 318. I made a huge mistake and left a rag in the motor and started it up. Needless to stay, it tore the rag up and it went through my motor. I found out because I changed or upgraded the distributor. Since I have to take my block apart, now to blow out all the oil passage lines, I would like to put in a 4 inch crank, is there anything special I have to do to put in a 4 inch crank? Any helpful? Suggestions would be greatly appreciated. I found a lightweight crankshaft on Summit racing for an internally balanced motor. What parts will I need to complete this?
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It seems to me that any rag-bits that made it thru the pick-up screen, should all be in the oil filter.
 
hwy2 said:
Which pistons
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Pistons to go with a 4" stroke crank with whatever bore size you're using. We're not gonna choose your piston for you. That's your decision to make regarding whatever you want the compression to be.
 
Do your homework and get prices for everything. It might be easier and cheaper to just get an engine from Blueprint or another builder of your choice. It'll save time too. Just throwing it out there.
 
michiganpat said:
honestly, if you're going to build a stroked 318, I'd start with an '85-91 block. they have factory roller cams, 302 heads. the roller cam is the biggie. you can get it reground, or get a roller cam and reuse the stock roller lifters at a much lower cost than the retrofit roller lifters.

putting a stroker crank in requires at a minimum new crank, pistons, and block clearancing if using stock rods, IIRC.

any 318's stock heads will be way undersized as far as flow to have any power above about 4k RPM
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rumblefish360 said:
You can check speed parts sellers like Hughesengines.com
Or Manciniracing.com for full or partial kits to stroke a 318 to a 390.
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85glht said:
Do your homework and get prices for everything. It might be easier and cheaper to just get an engine from Blueprint or another builder of your choice. It'll save time too. Just throwing it out there.
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Thats what I am thinking
 
Kits are available.

.040 over makes a 392.

One of Mopar's "magic numbers".
 
85glht said:
Do your homework and get prices for everything. It might be easier and cheaper to just get an engine from Blueprint or another builder of your choice. It'll save time too. Just throwing it out there.
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Does blueprint have 360's...?
 
YY1 said:
Kits are available.

.040 over makes a 392.

One of Mopar's "magic numbers".
Click to expand...
Ordered a 4 inch balanced assembly icon forged pistons yeah it’s gonna be a 392 now!
 
Well good luck. I passed on a 318 build one of the guys started but didn’t finish. The old adage is if you put a million dollars into a Volkswagen you will have the fastest and most expensive Volkswagen in town. Just make sure the end justifies the means
 
d5667 said:
Well good luck. I passed on a 318 build one of the guys started but didn’t finish. The old adage is if you put a million dollars into a Volkswagen you will have the fastest and most expensive Volkswagen in town. Just make sure the end justifies the means
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I would not put a dime into a VW but a 71’ demon has alll my money. Won’t be the fastest but I bet when Im done it will beat my 2017 scat. If it beats my challenger then the ends are justified IMO.
 
392 from a "just a 318" has additional "cool factor" money can't buy.

:thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup:
 
I've thought about it myself. I've got a couple of magnum blocks sitting here...
 
The 318/392 has a longer stroke than the modern 392. Over 4” bore. I wonder how the torque is going to come on. 318/392 will it be a better low revving motor 5600? Or more of a 6k+
 
I'm thinking it'll be slightly under square, I'm thinking of doing one up for a 3/4 ton 80s truck. Tow pig.
 
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