Why are 318's low HP and torque?

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Meet-Joe-"Dart";1969497044 said:
Such a cool thread.... I've got a 318 sitting on the floor of my shop.... this thread makes me want to build it into something really special.

I guess the thing is though for the amount of money your gonna spend on building a new motor.(let say you buy new pistons, rods, aluminum heads, intake, headers etc....) adding on a couple of hundred for a 360 core( or maybe a 340 if can find it) most guys are gonna go for the extra cubes.

Still I think a SCEEEEAAMIN 318 would be crazy cool!:finga:
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You should Man! Almost every thing would swap over from 360 to a 318 or vise versa. you just wont be able to use the 360s oil pan ,damper,crank,flex plate and pistons on a 318.:toothy8:
 
Meet-Joe-"Dart";1969497044 said:
Such a cool thread.... I've got a 318 sitting on the floor of my shop.... this thread makes me want to build it into something really special.

I guess the thing is though for the amount of money your gonna spend on building a new motor.(let say you buy new pistons, rods, aluminum heads, intake, headers etc....) adding on a couple of hundred for a 360 core( or maybe a 340 if can find it) most guys are gonna go for the extra cubes.

Still I think a SCEEEEAAMIN 318 would be crazy cool!:finga:
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Hey there meet joe dart. no need for those edel. aluminum heads. them RHS heads are the way to go. Setup by IMM with 202/160 and 5/16 stems, & beehive springs...can you say, LIGHT valvetrain!??!! :D:D:D mine loves to revv!! I really really like 318's now. they rev soo easy :) Just today I smoked the tires various times all over the back roads!
 
heres an older pic of my 318, we were in the middle of a re wire job

IMG_2982.jpg
 
Chryslerkid said:
Hmmm. I see. So a little of everything and I could really wake up my little 318 huh? Well I am building a mostly stock 318 right now. I currently have a street master four barrel intake manifold with a 650 Carter, stock exhaust manifolds... What else would be easy to do without breaking the bank to wake up my 318? Do you guys have pics of your 318 setups to give me some ideas?
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Stock compression height is 1.720. You can get some stock replacement 4 eyebrow type pistons with a 1.741 compression height. That might not sound like much, but it makes a difference. Get some Magnum heads or 302 heads and get them down to 55cc, have the block bluprinted to 9.6 (which is the factory spec, they're always high) use the .021 thickness head gasket and you have a 9.1 motor. Just right for idling around stuck in traffic in the summer and will never spark knock. Cheaper than setting up a quench motor. Those pistons only cost about 100-125 bucks, whereas the KB167 quench type pistons are around 400. Even if you choose to save money and not blueprint the block deck, you're still gonna have respectable compression considering the stock 318 blueprints in the 7s compression wise. You'll have enough to support a 325 HP 318 with smart parts choices.
 
Book specs I have say 67-69 LA 318's are 9.2:1, then 8.8 in 70, and 8.6 thereafter, until the last LA series with the roller cams and 302 heads which goes back up to 9:1.

Get an early or late core, and a decent cam, and exhaust and you've solved 2/3 of the "problem".

BTW, I've had several really torquey stock 318s, especially the 66 poly.

Storker- you got a part number for the "eyebrow" pistons, and maybe the largest safe cam lift to use with them?

Larger bore than stroke is called "oversquare", and it's good for torque.

Yes, the 318 could have been the "327" of Mopar. I often compare the two.

I think the somewhat poor performer reputation came from two main sources (besides the small cam small carb issues)-

1- early 318's had lots of attention getting competition, and no one noticed them
2- most folks are familiar with the mid 70's to early 80's 8.x:1 motors.

For the record, my 80,000 mile 66 poly 2bbl was a 70s and 80s 350 killer.
Never lost a street race to a GM product.

As stated previously, the worst part of that deal, was the GM guys always shrugged and said "of couse you won, you have a big block!" after they saw under the hood.
 
YY1 said:
Book specs I have say 67-69 LA 318's are 9.2:1, then 8.8 in 70, and 8.6 thereafter, until the last LA series with the roller cams and 302 heads which goes back up to 9:1.
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Trust me. Whatever "book" you got that out of is WRONG. lol
 
I just want my 318 to be able to feel like a v8 when I punch it at the stop light and burn out without blowing up. Lol. I don't need to go too radical because I still want to be able to drive it around town frequently. If I do decide to get different heads, which ones will be an easy bolt on?
 
302 heads will be cheapest for you if you can find some uncracked that don't need guides or seats. You can get compression in the 9:1 area with little effort. 325 HP isn't out of touch with good parts choices with that compression.
 
What are 302 heads from originally? Will I need a different intake manifold if I get the 302's? Thanks.
 
kid, given your goal... what rear end do you have in the car? I think you could get a good start to doing what you want by changing that out if you have a high set of gears now.
C
 
This thread needs to be Sticky'd because the topic comes up every month or so...when the other one finally dies.....

:happy1:

Find a 87,88, Chrysler Fifth Avenue in the junkyard....or classifieds....or someones yard on flat tires.....

Offer em no more than $400 for the car/engine....and you would have your hands on a Roller Cam LA 318, with 302 casting cylinder heads.

Or you can get one out of a truck line 87,88,89,90,91,92 D150, B150, Ramcharger....but at that point you realize there is an even better Roller Cam LA block out there available these days.

88 was 25 years ago folks.
The dodge and chrysler Roller Cam LA SB equipped family is finally starting to show up in the yards after long dependable service.

And the engine to really look for is the 88-91 Roller Cam 360.
Only produced in the Truck Line, and ONLY in the Ramcharger 4x4, D250 2/4wd, and the B250.
But they are out there....and I am finding more and more everyday....so I recommend you do the same.

4" Bore x 3.58 stroke....opposed to the 318/340 stroke of 3.31
Steel Timing Gear Set...instead of the 100% only 318 nylon gear set
HD Oil Pump
Roller Camshaft
308 casting cylinder heads with OE 1.88/1.60 valves and Unleaded valve seats...plug the smog ports and their good to go.

Those 360's are the cats meow.....:prayer: in stock form....In MY Opinion.

A 408 stroker based on one of those could get pretty radical NATURALLY ASPIRATED.

I am building one myself....and have some serious plans for the whole car....if it will ever get PAINT on it....,
MY Roller Cam 360 is shooting for WICKED :twisted: on 20 psi Forced Induction.
and I hope to see 600+ at the wheels in Race Tune.

The sky and your pocket book are the limit.
 
Awesome reply, Prine. Thanks.
 
I already have a 318 engine from the 80's so I must have the 302 heads already right? I looked at them and they have an "M" stamped into them....? Hmmm. Don't know durrr.

Oh yeah I have the stock 7 1/4 rear end in there right now. I am looking for a 83/4 rear end while I get the engine and trans in order....
 
Look at the serial number underneath the valve cover.. Last 3 numbers will tell you what heads they are.
 
Oh okay. Well I'll do that tomorrow and get back to you guys ASAP. Thanks for the tip.
 
If your on a limited budget I'd leave the long block alone
4 barrel, cam and duals with or without headers plus shift kit and gears is the way to go. I read about a build up with a stock 318 they used Comp cam XE262H, M1 dual plane, 650 Holley and headers made 282HP @ 5000 even without headers still would make 250HP.
P.S. streetmaster intake isn't all that great of an intake but will do for now, than down the road you could go with better heads and intake.
 
Hmmm. Okay. Well I have headers already so at least that'll help a lil bit. I just got my oil pan and I'm going to put it on tonight. Going to drop it in soon! Does anyone know if I will have issues putting the engine and trans in with the headman headers on the block?

Also no one confirmed or denied weather or noth my engine already has 302 heads? My engine is from the 80's
 
302 heads came out in '85 and ran until the magnum engines came out, so '85-91. If your 318 has 302 heads, it should also be a roller cam engine unless the heads were added later.

Keep in mind though that not ALL of the LA 318's from '85 to '91 had 302 heads or roller cams, there were still non-roller, non 302 headed versions of the 318 that ran from '85-'89. If the last 3 digits of the casting number on your heads is 345, then you don't have a roller cam. If you have "646" heads you may or may not have a roller engine. In either case, you don't have 302 heads. If your 318 is '89-91 its has a roller cam, but it could still have 646 heads instead of 302's.
 
StrokerScamp said:
Trust me. Whatever "book" you got that out of is WRONG. lol
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I haven't confirmed but, I believe he is talking about advertised compression and not "static" compression. Even the earlier 67-69 blocks should be about 8.2.1 to 8.5.1 static? The later they the worse the compression height became and then after 72 was all downhill.
 
For the record my 67 FSM says 9.2:1, and my 1969 Motor's manual also says 9.2:1 for 1969 and older LA 318s. I have a 72 FSM somewhere, but can't locate it.
 
YY1 said:
For the record my 67 FSM says 9.2:1, and my 1969 Motor's manual also says 9.2:1 for 1969 and older LA 318s. I have a 72 FSM somewhere, but can't locate it.
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I believe the confusion here is the advertised compression vs "static" compression which involves measuring the compression height and cc volume of the combustion chamber but, I believe your advertised numbers are correct.
 
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