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318 opinios keep or toss?

I like my 318 if it was a big block i'd love it! lol only problem with mine is the guy i bought it from built it and put 360 heads on it but i don't think he got the right pistons because i only get like 10mpg in mine...
 
Hey Guys,
Just wanted some feedback from those that have a 318. Is the power enough for regular driving? I keep hearing mixed reviews. Everyone seems to want to dump them for 340s and 360s. So keep or toss and why... Trying to decide what to do with the "Death Row Charger" (great name given to my 1974 Charger by a poster here):icon_axe:

Leave it alone. I had a '70 Satellite with a 318. I was doing doughnuts in the church parking lot when I over revved it and bent a few valves. I pulled the 318/904 and but in a 383/727. Average gas mileage was FAR worse, went from 20.2 to about 16.5. The 727 tranny is heavier and takes more horsepower to spin than the 904. The 318 LA is a nice light engine. Put a four barrell intake and some long tube headers to increase torque and leave it alone. You could also pull the heads and have them shaved a little, this would increase fuel mileage and horse power. I love the 318LA's. I might put one in my '66. I know the '67-70 model 318's were rated at a good 230 hp to the flywheel.

but I do more cruising, commuting, and traveling than racing.
 
To 69clone and others,my first attempt at H.P.many years ago was to put 360 heads with 2.02 340 valves on a 70 stock short block with a 284 .484 purple shaft.This thing with 3.23 gears was a mutt of the line,make a couple of ponies when I got it spun up but still a dog.Later I was to calculate it had 7.5 to 1 compression.Boy what I didn't know.I stongly suggest getting the book How To Hot Rod Small-Block Mopar Engines by Larry Shepard or Mopar Performance book and read read read.Don't make my mistakes and ask any question.No Question Is Dumb.If you can't learn what you should,you will sure learn what not to do.
 
I like my 318 if it was a big block i'd love it! lol only problem with mine is the guy i bought it from built it and put 360 heads on it but i don't think he got the right pistons because i only get like 10mpg in mine...
WHOA! 10mpg's is a huge problem. If you so desired to improve the teen, sell/trade the 360 heads in favor for 318 heads. 302 series heads are very good. If they need to be rebuilt, I suggest a 1.60 exhaust valve over the 1.5 A 1.88 valve works well with a 340 cam or better. (Bigger) Also bowl porting at that level, but thats another story.....

A MSD is excellent in finding mileage.

I stongly suggest getting the book How To Hot Rod Small-Block Mopar Engines by Larry Shepard or Mopar Performance book and read read read.Don't make my mistakes and ask any question.No Question Is Dumb.If you can't learn what you should,you will sure learn what not to do.

Amen! Great advice!

This has been a real informative thread,. What would you do different if you built a 360? Bigger exhaust ,bigger cam?
As a performance machine?

straighten out that block right! Overbore only if needed to.
KB-107 flat top zero deck height intalled slugs.

Federal Mougal has very similar pistons, 2 sets at a ever so slightly lower height. So more streetabl;e ratos can be selected with smaller cams that do not bleed off compresion as well as larger cams would do.

A cam that is used in your cruiseing RPM range (Pay attention to intake duration @ 050 and the manufactures description of the cam) with an amount of lift that doesn't exceed the air flow abilties of the head used. Which brings me too..........

Heads; OOTB Edelbrock heads need to be examined and possibley touched up. I still think there a good deal if your goal is a very high street performance engine.

INDY's new S/B head. Excellent street machine material. Check with Brain (ou812) over at FABO. Well worth your time!

OE iron heads, great for cruiser to street machine duties. Probably cheaper to do than the above choices. There performance ceiling is limited...or out done by the above heads. But still very good to use. Dead reliable and solid choice for longevity.

Headers. I skip the 1 size fits all style. I hate them and there none changed defective 30+ year old design.
IMO, use ethier;
Doug's - good
tti's- supieror all around
Hooker Super Comps - cheaper than tti's a little more race styled.

All fit great and should be connected to a min. of 2-1/2 exhaust.

RPM, or Stealth/action plus from Weiand are excelent intakes.

Cfm's float between actual build. 600 - 750 will do most chores.
(I like the TQ myself. but any carb tuned well is a good carb to run.)
 
Hey rumble,good stuff.What are your thoughts on 3.31 forged crank with Hughes girdle and upper end performance goals.
 
I dont know if I would go with exotic parts on the 318. In close to stock form they run pretty good. 18 to 20 mpg should be easy while making respectable power.

If I was building a new motor I would go with stock cast pistons. Try and get the compression close to 9 to 1.
Cast crank or forged crank makes no difference at this performance level. Cast is actually lighter so that may be a better choice.
As far as head selection goes I would stay with a closed chamber head. I would actually go with a small valve head to keep the velocity up for the air fuel mixture as it enters the combustion chamber.
I would go with mild cam probably keep the lift at or less than .450 with out a lot of overlap. The closer to stock the cam is the more bottom end torque you will have.
I would use a dual plane intake manifold like an Edelbrock performer. A 600 CFM Carb would work good and when jetted properly give good fuel mileage.
Make sure you use a distributor that has a functional vacuum advance.
A stock torque converter will work fine with this combo.
For exhaust I would use headers as there is not any other mod that will give you that seat of the pants performance boost. If you want to stay with manifolds it will still run good though..Either way go with a dual exhaust set up around 2 inch to 2 1/2 inch.

In my opinion if you plan on spending more money on the project I would just build a more serious 360 or 340 or bight the bullet and go big block.
 
Hey rumble,good stuff.What are your thoughts on 3.31 forged crank with Hughes girdle and upper end performance goals.
A waste of time & money for street service, performance goal or not.

I dont know if I would go with exotic parts on the 318. In close to stock form they run pretty good. 18 to 20 mpg should be easy while making respectable power.

Just incase you were thinking that my above write up was for a 318, it wasn't, it was for a 360.
Good thoughts on the 318 build for a very mild engine and longevity with a mileage minded approach.

I do make a note to the exhaust pipe sizes you mentioned. 2 inch to a 2-1/2 inch in exhaust pipe sizing is a huge difference.
 
10mpg? I just drove my duster from Texas to North Carolina. 360, 727, 3.91's, twisting 3400+ all the way and I got anywhere from 14 to 15.6mpg
 
A waste of time & money for street service, performance goal or not.



Just incase you were thinking that my above write up was for a 318, it wasn't, it was for a 360.
Good thoughts on the 318 build for a very mild engine and longevity with a mileage minded approach.

I do make a note to the exhaust pipe sizes you mentioned. 2 inch to a 2-1/2 inch in exhaust pipe sizing is a huge difference.

Yeah I missed the part where it was for a 360. Sorry about that one and I did see you mentioned the exhaust size. When I started typing I just was trying to think how my old 318 was put togeather and was typing all the specs that I could remember. I realize I may have restated things you have said also.

My Sattelite now sports a 383 with 11 to 1 pistons 3500 stall converter and is not too friendly on the gas mileage. I miss the 318. I am thinking of putting a stock 318 out of 91 Dakota with the stock roller cam in my old 67 Dodge Dart project. The car is rough but it could be fun. It has an 8 3/4 open 3.23 rear axle disk brakes and everything else is pretty much stock. I have headers for it and manifolds. I may just put it togeather with the manifolds and modify it later. Would be nice to get that gas mileage back.
 
OK, so I'm hearing a lot of people saying that 360 heads are a bad idea on a 318, mostly 'cause they'll kill what little compression a 318 has. But then I've seen X-heads on a 318 (not mine) that ran like a champ. (Or at least it did until the owner swapped in a 340 6-pack cam. After that it barely ran.) X heads are open-chambered heads.

And then there's the cop car 318s from the early '80s (also open chamber). I found mine bolted right to the stock 318, and they have "360" cast right into the intake runner. Cop car motors had a higher hp rating than a regular 318, or even a light truck 318 with a 4bbl. It seems to me like a more free breathing head is only going to make it easier for the engine to do what it's going to do anyway, as long as you don't get all stupid with the cam. So what gives? :munky2:
 
You can run the big valve heads and if you already have open combustion chambers you will not drop too much compression. I really feel that for a mild build the stock small valve heads will work better. You will have more torque and that is what the smaller motors are lacking......I used to run a 340 in my 67 Dart. I built the shortblock stock with the exception of an Erson cam TQ40 that was about .492 lift if I remember correctly. I didnt have heads so I used the fresh but stock heads from my original 273 that was in the car and the proper valve springs.
The transmission was the stock 904 Toque flight, the rear axle was a 3.23 open 8 and 3/4.. The car had headers and flowmaster mufflers all the way out the back. the car ran 13.89 at 98 mph. That was quicker than stock 340s with the big valve heads. The car made tire melting power right off the line and never gave much back on the top end. That was running a small port small valve closed chamber head. My intake manifold was an old edelbrock LD4B with a 625 Carter AFB. I know that was a 340 but it does show some merit of the small valve small runner head when running a stock torque converter....
If you wanted to really hot rod it out you could go with the steep 4.56 gears and high stall torque converters then running large cam and big valve heads would play into your favor...However every day drive ability and gas mileage would suck.
 
OK, so I'm hearing a lot of people saying that 360 heads are a bad idea on a 318, mostly 'cause they'll kill what little compression a 318 has. But then I've seen X-heads on a 318 (not mine) that ran like a champ. (Or at least it did until the owner swapped in a 340 6-pack cam. After that it barely ran.) X heads are open-chambered heads.

And then there's the cop car 318s from the early '80s (also open chamber). I found mine bolted right to the stock 318, and they have "360" cast right into the intake runner. Cop car motors had a higher hp rating than a regular 318, or even a light truck 318 with a 4bbl. It seems to me like a more free breathing head is only going to make it easier for the engine to do what it's going to do anyway, as long as you don't get all stupid with the cam. So what gives? :munky2:

Between the cam size and open chambers of the head, it's no wonder it died on performance.

the comprsion of the 318 is likely to spec out when measured and mic'd up to 7.5-1.

The "360" cast into the head does not denote ?make it a 360 cid head.

the higher HP rating is a give me on the 360 headed 318's but what they don't tell you is the torque is down across the baord until the RPM's go up. Excellent for cop cars in pursuit.

If you up the cam size, you'll need some decent comprsion to make up for the overlap loss of the cam. This is a know item soooo often overlooked and ignored and only to be followed up by the question..... why did that happen?

You can build a 370 HP 318 with a 7.5-1 ratio. However, @ 3% more power per ratio point, a 10-1 is 6% more power equals more than 400 HP.

this is just based on raw numbers on ratio and does not consider a well build engine with a good quenched area and added engine efficentcy.
 
OK, this is starting to make a little more sense for me. I've got weird tastes. I tend to favor cop-car acceleration and like mild gearing... probably because I prefer long distance highway use over drag racing. It sounds like my preferred setup is more suited to this kind of driving.

The tightest 318 I ever owned had 273 heads on it. My cousin had the car before I did, and he swapped them when he did the cam. He said he couldn't see any difference whatsoever between those particular 273 heads and the stock '74 318 heads, including casting numbers. And yet... that motor was something else. Even with the stock BBD 2bbl carb. There's nothing quite like dusting off a shiny, new BMW with a rotbox 4-door Coronet that has flapping fenders and a 2bbl. In heavy snow. :)

As for the über-cammed 318, all I have to say is this: you can tell people stuff 'till you're blue in the face, but sometimes they just have to see it for themselves.
 
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