318 lives matter
Build what you have...it's a great platform!
Jeff
Build what you have...it's a great platform!
Jeff
318 build need ideas first build
- Thread starter Mike74012
- Start date
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Yes there is reason to build 360 over 318 but to me anyone building less than a 440 is leaving performance on the table.
Hp wise 318/340/360 basically have the same potential since they can share the same parts.
The main draw back is the 318 head it can be made to work and is fine for under 300 hp. But why bother when there tons of 340/360 magnum and aftermarket heads.
There's 2 main components in building hp cam and heads. There's two ways of going about it the main being rather large cam (& cr) with too little head. Or how most modern muscle engines are mild cam and race car cylinder head flow numbers.
Take a look at 5.2 magnum vs 318 la. We all know the magnum head ain't no hemi head but does offer 400-420hp OOTB and that's with 9:1 cr. The 300 hp create engine makes about 320 hp with headers and there's no reason to think the 5.2 isn't close. Add a mild 264 roller cam and you got a mild 350 hp engine do some porting or aftermarket and gain 30-50 hp. To do that with a 318 with non ported 318 heads might be able to squeeze 350 hp with xe286hl cam and 10:1 but definitely be less streetable than the magnum version. And with a ported 318 head will hit 400 hp cause that's one of the 400 hp 318 recipes.
But here's the main drawback is gear ratio.
There's no reason a 318 can't make the same hp as a 360 with similar parts it's just gonna happen around 600 rpm higher.
So gonna need at least 600 rpm more stall and 2 gear sizes lower to equal the performance difference out.
Hp wise 318/340/360 basically have the same potential since they can share the same parts.
The main draw back is the 318 head it can be made to work and is fine for under 300 hp. But why bother when there tons of 340/360 magnum and aftermarket heads.
There's 2 main components in building hp cam and heads. There's two ways of going about it the main being rather large cam (& cr) with too little head. Or how most modern muscle engines are mild cam and race car cylinder head flow numbers.
Take a look at 5.2 magnum vs 318 la. We all know the magnum head ain't no hemi head but does offer 400-420hp OOTB and that's with 9:1 cr. The 300 hp create engine makes about 320 hp with headers and there's no reason to think the 5.2 isn't close. Add a mild 264 roller cam and you got a mild 350 hp engine do some porting or aftermarket and gain 30-50 hp. To do that with a 318 with non ported 318 heads might be able to squeeze 350 hp with xe286hl cam and 10:1 but definitely be less streetable than the magnum version. And with a ported 318 head will hit 400 hp cause that's one of the 400 hp 318 recipes.
But here's the main drawback is gear ratio.
There's no reason a 318 can't make the same hp as a 360 with similar parts it's just gonna happen around 600 rpm higher.
So gonna need at least 600 rpm more stall and 2 gear sizes lower to equal the performance difference out.
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The 318's draw backs are cylinder head/valve size & cylinder bore size. If you sonic check your block for thick sleeves, you might want to go there.
Common overbore size is
318 + .030 = 322.85
Uncommon overbore size
318 + .060 = 327.79
Rare if ever overbore size
318 + .090 = 332.76
I forget the place that does indeed use 318 engine with a 4.00 crank in there create engine, but the block is sonic checked first and if they pass there min. cylinderbore thickness, they proceed to stroke it. That would be 402.12 create engine.
Bore size 3.91 = 384
Bore size 3.94 = 390
Bore size 3.97 = 396
Bore size 4.00 = 402
Sonic check your block!!!
Common overbore size is
318 + .030 = 322.85
Uncommon overbore size
318 + .060 = 327.79
Rare if ever overbore size
318 + .090 = 332.76
I forget the place that does indeed use 318 engine with a 4.00 crank in there create engine, but the block is sonic checked first and if they pass there min. cylinderbore thickness, they proceed to stroke it. That would be 402.12 create engine.
Bore size 3.91 = 384
Bore size 3.94 = 390
Bore size 3.97 = 396
Bore size 4.00 = 402
Sonic check your block!!!
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Didnt know about sonic checking cylinder walls. Guy that built the 360 in the duster i bought should have done that. I can see the hole.
318 truck (premium block) engines can be bored.
A wealth of information here, hope some of us can put it to good use.
318 truck (premium block) engines can be bored.
A wealth of information here, hope some of us can put it to good use.
A Edelbrock head has 65cc's. Combined with a zero decked piston, .030 overbore & a 4.0 X .038 head gasket, your comp ratio will be 9.44-1 Very good for the street and low octane.
10.02 @ 60cc
10.27 @ 58cc (W5 and ... )
Both ratios are excellent for high performance and premium pump gas.
(10.41-1 @ 397 bore. 10.56-1 @ 4.00 bore.)
Higher compression ratios will require ether a dome or a small chambered heads to start with a then heavily mill.
A 4.00 stroke with a bore of;
3.94 X 12.21-1
3.97 X 12.38-1
4.00 X 12.55-1
10.02 @ 60cc
10.27 @ 58cc (W5 and ... )
Both ratios are excellent for high performance and premium pump gas.
(10.41-1 @ 397 bore. 10.56-1 @ 4.00 bore.)
Higher compression ratios will require ether a dome or a small chambered heads to start with a then heavily mill.
A 4.00 stroke with a bore of;
3.94 X 12.21-1
3.97 X 12.38-1
4.00 X 12.55-1
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stroked340
Well-Known Member
Saw this...had to post it....
Ha ha ha- to funny.
are you talking in a bracket race? If that's the case, you can put a hemi on the trailer with a /6. If your talking head to head racing, if you beat a 440 then all wasn't equal. By the way, I read all the time right here at FABO of 360's struggling, and my 318 would beat them. Doesn't mean it's the tale-tale to the whole story.Are you talking a big block 440??..if so I don't agree kick the snot out of many a big block with a 360
- wait, why am I wasting time, this is just repetition of years past......
stroked340
Well-Known Member
I'm talking heads up..been done many many a time and a few hemi's too..with a "stock stroke" 360
yep, it CAN be done. Doesn't mean for a minute that the 360 is a better build than a 440, or that the 360 makes more power than the 440. That's just stupid think'n. There has been 273's go into the 10's, does that make a 273 a better build than a 340 or 360? Especially when a lot of people are in the 14's with their 340's/360's.I'm talking heads up..been done many many a time and a few hemi's too..with a "stock stroke" 360
stroked340
Well-Known Member
Well I would think you'd need to build the 340/360 better then the 440 to beat it..340/360 running 14's obviously they're not built right..I wouldn't waste my time going to the track with anything not running at least in the 12's
Thread cleaned. Back to the original topic.
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