Edelbrock Heads for 318

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Nothing wrong with that intake for a light strip ride. (Hi gear-hi stall- light weight)
Runing the street with the engine?
 
Back in the early 70's some racers were limted to 305 cubic inch's and all of them put a 3" crankshaft in the 340 blocks to get 305" out of it. Sure they could have sleved it for smaller pistons or put a longer stroke crank in a 273 block but no, RPM's were what matter cause the rules did not say how fast you could spin the motors. So they were running 13-14-1 compression and 8000+Rpms. If they would have went with the smaller pistons and longer stroke crank they would have not been able to spin the motor so fast. Now of days with this crapy gas we can not run 13-1 compression but if you could a short stoke motor would come out on top every time if it had the right heads and cam. RPM's wins over stroke. The faster you spin the motor the more air you can pump in and out. Sure long stroke motors are great for low compession RPM motors but thats only cause the short stroke motors can not spin 8000+ with 9-1 compession. The cam and heads are too big for 9-1 for any low rpm's but if 2 same cubic inch motors had 13-1 compression and unlimted choice for heads and cam-and good gas-the short stroke motor would make more power cause it can spin much faster.
 
RPM's wins over stroke
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I hate to differ, but I would rather side with Carrol Shelby than your quotes. Look into history and remember that the Europeans laughed at the Ford big bock entry while standing next to there short stroke (And very at that) engines.
the short stroke motor would make more power cause it can spin much faster.
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True and not true. From what I have noticed, not that I test these things daily mind you, but the HP difference is small, in veiw of the big picture, even more so.
The nice thing about a longer stroke is peak HP comes sooner while retain superior torque in getting there.
Sure long stroke motors are great for low compession RPM motors but thats only cause the short stroke motors can not spin 8000+ with 9-1 compession.
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Totally not true. Look over to the old NASCAR truck series. The engines are limited to a 9.0-1 ratio but yet produce over 700+ HP. Also remember that each truck/team have several engines for the several sized tracks they will run at. Shorter tracks require a different engine than a Super Speedway. All engines spin to the moon.
RPM is limited to piston speeds and valve spring limitaions. (SP all over, sorry)

A short stroke engine has the abilty to spin more rpms because of it's shorter stroke and that means piston speed is less with a short stroke as compared to a long stroke engine. The piston has to travel father in the long stroke engine. So for the same given RPM, the piston has to move faster.
Apple to apple. (?)
But I have seen 3.79 stroked small block rip past 8,000 rpm. That was one hell of a Dart.
Engine stroke on a race corse should be thought out. Do you need more torque for turns and twists. Going up hill?
 
If the longer stroke motor stays together at super high rpm's like a short stroke motor can, then yes it make more power. But you are talking big $ and thats only posslable now cause of the high tech stuff avaiable now. I am not sure how much stroke those grand prix cars they have over seas have but they rev over 12,000 rpms now. Thats why they sound so different. I do know they cost well over a million dollars. Back to our great little world, I agree that a 360 for us with today's gas is the best way to go if you want the most power and diverablity. Those NASCAR 9-1 motors would not be good on the street, you look like a freak idling at 3500 at the stop light. The motor needs high compression to idle low with a big heads and camshaft.
 
If the longer stroke motor stays together at super high rpm's like a short stroke motor can, then yes it make more power. But you are talking big $ and thats only posslable now cause of the high tech stuff avaiable now.
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In a apple to apple, I really don't exactly see it that way. You don't need hi dollor stuff, just a real good machinest. Over the top rpm like the trucks or a good race ride, yea...it would be best to pay the piper. Even years past, to get rpm up high, you needed to spend. So, nothing has really changed. Just the parts have gotten better.
Those NASCAR 9-1 motors would not be good on the street, you look like a freak idling at 3500 at the stop light. The motor needs high compression to idle low with a big heads and camshaft.
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It's more so the cams fault more than anything when it comes to idle and quality thereof.
The larger solid rollers with a very low centerline and huhge overlap cause crappy idles. I don't know what those trucks idled at, but in all actuality, they could be street driven. Seriously dont see a 3500 idle.

Is there a NASCAR guy in the house that would know what these things idled at?
The truck series engines.

He he he, our little world. I hear ya there. No matter whats doing, just build a solid bottom and the rest is cake. (May not be cheap......but no good Hooker is.)
Oh, by the way, I do look like a freak, LOL, just playin. :wav:
 
Thanks for all the help, but now I am looking at a coulpe of places that sale crate 318's with 370+ hp. Another place could build a crate motor to my specs. On top of that a 1 year, unlimited mileage warrenty.

Thanks again, I'll keep you all posted.
 
NOW!!!!!!!!.....if your gonna BUY a crate motor or have a shop build you a motor,WHY would you want a 318???? :sleepy3:

ive NEVER heard of a crate 318 making 375HP.....a 360 makes 385HP!!!! :wav: .....just buy the 360 and be done with it!!!! :thumbup:
 
The is 318 is a 390 stroker with high flow heads, intake, and performance cam. I am looking to get one built in the area of a 340. My dad has a 70 340-6 T/A. I like the quick reving hp. :headbang: Besides everyone uses the 360, I want to go different.:thumbup:
 
So its NOT a 318 then, I still don't understand why not a 360 stroker thats like a 408, still 18 CI bigger. ATI trans has their own crate engines now and a 408 chrysler is $4,996.00 and its 450HP at 10-1 comp. Comes with a 12 month warranty. Fully dynoed and cam broken in. Just drop it in and drive away. Not sure if its online yet, wasn't this summer when they first came out. www.atiracing.com Don't see it but its in their catalog, its has all new valves, hyper pistons, new oil pan, sounds nice. The race motor has forged pistons but 11-1 comp. makes 525HP and cost $6,996 again race only
 
Mopar crates are not dyno tested or run. They are spun to test for oil pressure, and in some/many cases, they ignored what the reading was. The MP 408 uses stock rods, and hypereutectic pistons too. IMO, neitehr of those belong in an engine that uses a 4" stroke. Not because they are junk. I recommend thier use and use them myself all the time. But because everything has a design limit, and with a 4" crank, those pistons are at their limit by 63-6500 rpm, and the rods slightly higher with the lighter weight of the pistons. The hyper piston requires stock LA rods to be narowed at the pin end to fit the piston. So they run Magnum rods. You never see factory rods or hyper pistons in kits for sale. Well, almost never. That's because the good builders dont want to build to the limit. They want to build beyond the limit just in case. Cheap is just that.

Now, back to your 318 build..A 318 witht eh 360's 3.58 stroke crank is a 349. But it's not a 318 anymore. 400hp is easy to get form a 318/321...But you need to realize it will be at a higher rpm point than a 349, or a 360 if built identical. The reason the 390 idea is around is because the same crank and rods that are used in 416 (340 based) engines will drop in a 318 block with no more mods than the rod clearancing. So a custom piston and you're done. The magic is in the crank. That longer lever gets you more power where a street car needs it. So build whatever you like. I dont like crate engines, but that's me.
 
No ATI builds their own motors, they say just 1 person does the work putting it together, Mopar's are crap, I would trust ATI racing for my motor. This is what it says--hypereutectic pistons, forged steel rods, cast steel stoker crank, hydraulic cam. The race but for street use they claim has a forged steel crankshaft and pistons , eddy heads and a soild cam. Guess thats why its 11-1 it has those eddy heads that cut the comp. down 1 point. Other options are available.
 
Lose the hyper pistons...and find out about the rods...are they LA, or Magnum style? They should be able to tell you and maybe upgrade for decent money.
 
man all this hating on the 318, thats pretty sad especially when some of us have 318s that will put your 340 and 360s to shame and some big blocks. My 318 stock stroke is turning 7.15 to 7.20s in the eighth mile I dont think thats anything to be ashamed of an I can say its a 318.
 
If you stick a 3.58 stroke crank in a 318 you shouldn't have to clearance the block right?
 
:lurk: I just gotta say, I use a 318 in my 67 cuda. It has torque and runs strong. It's 9.8-1 and has a he260. I love that motor and have 2 more on engine stands. Mines a cruiser and I don't think a 360 would make it anymore fun. Have fun building it but remember what you want to use it for.
 
Lars said:
If you stick a 3.58 stroke crank in a 318 you shouldn't have to clearance the block right?
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The only time you need to clearance the block is when you use the 4.00 stroke crank and I think it's only the rod bolts that need the clearancing.
I also understand it's rod dependent. Some aftermarket rods cler better than stock parts.

Double check that info. But the 3,58 crank just drops in, no problem.
 
rumblefish360 said:
Double check that info. But the 3,58 crank just drops in, no problem.
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OK, that's kinda what I expected since 318's and 360's have the same dimensions.
 
fast318dart,
I'm with you as I have one that runs 6.90's and can run 6.70's when not detuned for consistancy, so I know it can be done, and I'm with you. Kudo's my Mopar Brother!
 
The 3.58 crank needs some metal to balance. Will add a few $ to the build.
That 18 that runs low ETs is no cheap build either. 2.02 heads are too big for any enging under 360-375 cubes. Thats what we have, we use it. Never put 2.02 on a 318. Velocity in the dumper! Velocity is King! flow is Jack without it.

Flame away boys! I know its true!
 
70Barracuda said:
The 3.58 crank needs some metal to balance. Will add a few $ to the build.
That 18 that runs low ETs is no cheap build either. 2.02 heads are too big for any enging under 360-375 cubes. Thats what we have, we use it. Never put 2.02 on a 318. Velocity in the dumper! Velocity is King! flow is Jack without it.

Flame away boys! I know its true!
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While I understand that a teen needs port velocity, 2.02 valves may not mean a death sentence immediately (IMO), especially if you are using a power adder.

Oh yeah, and I wouldn't cut down a 360 crank when I can just buy one new with the mains already the correct size.
 
OK then I have a question? Why does it take a 800-900 CI engine and NOS to run like a 500CI ProStock engine, they have more bore and more stroke, but yet they arent that much faster and have more CI. And by all right's they should be faster.
Then why did they go to a smaller engine and run a blower instead of NOS because they found something that made the engine faster. Bigger isn't always better and attention to detail is everything.
I was told by a very good nitro racer/Driver that if it can't be done on 500CI then something is bad wrong, being a fuel tuner/racer myself I understood as I progressed and now adapt it to everyday engine building. I get called a liar everyday and that it can't be what I say it is but no one will prove me wrong and buy the engine for what they think that it's worth for how fast it runs, and if they build one that it doesn't run as fast. I can only say that they didn't pay attention to detail, and in a engine everything matters. So if someone can build a 318 engine that fly's and can run faster that the rest then I say give him/her credit, they did there home work. Maybe I'm over stepping my bounds here but I know how many people here have disagreed with me and thought I was full of BS, but yet a year later they come up to the same conclusion, so go figure. Everyone has there own opinion and way of building things so I for one give KUDO'S to the ones that deserve it, and as he's doing it I give him the credit!
 
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