Not sure what to do

-

hunukenny

New Member
Joined
Oct 4, 2023
Messages
4
Reaction score
5
Location
colorado
Nothing is wrong with my current engine, its a bone stock 318 from 1974. i want to get more power without spending too much money. would it be smarter to put better parts on my current engine or swap it out? i assume the engine has over 120k miles, the odometer broke before i bought it.

Would cylinder heads with bigger valves and a performance cam be worth the trouble or should i save my money and buy a short block crate engine? thanks for any thoughts and ideas. i want to have fun with the car but it seems to be a money pit when it comes to making it handle and have power
 
There is hundreds of threads already written about 318's in this forum. Use search and put 318 in the box then click "title" The list will be long.
 
budget dictates everything.

how much you wanna spend?

after that, expectations: how much work you want to do, how long you want it off the road, etc. etc. etc.
 
If your motors in good mechanical shape and isn’t burning oil, you’re probably fine to put a four barrel on it and do some basic mods. As suggested above, do a search for 318 mods. Putting a set of heads on it at this point probably won’t gain you much other than spending a lot of money that you can put into better performance modifications.
 
Nothing is wrong with my current engine, its a bone stock 318 from 1974. i want to get more power without spending too much money. would it be smarter to put better parts on my current engine or swap it out? i assume the engine has over 120k miles, the odometer broke before i bought it.

Would cylinder heads with bigger valves and a performance cam be worth the trouble or should i save my money and buy a short block crate engine? thanks for any thoughts and ideas. i want to have fun with the car but it seems to be a money pit when it comes to making it handle and have power
As long you got a mechanically decent engine no reason not to do the basic tune, 4bbl and mild cam with at least duals, headers better, stall and gears help too. No reason can't get 240-280 hp.

Here's stock low cr 318 long block with 4bbl headers and xe262h cam for 282 hp @ 5000 rpm..

https://www.motortrend.com/articles/mopp-0312-318-long-block-bolt-ons/

Problem is if you want more power then that, question becomes does a 318 make sense or better off with 360 or bigger. It depends and all is debatable and people will for 10 plus pages :)

But to add some parts to an already running engine and gain 50 plus hp is a no brainer to me.
 
318 cu in..........is always going to be 318 cu in. And it is never going to feel like 418 cu in.......

I agree with above. A four barrel intake is probably going to give you the best bang for the buck. Easy to do, minimal amount of work, minor engine disassembly..

If you wanted a large HP increase, better to get a bigger engine.

Use the Performer intake [ not the RPM ] & a 600 Edel AFB carb. Some will come come after this post & recommend the 650 AVS carb. For this performance level, it will NOT add anything over the AFB except to lighten your wallet...
 
And remember any mods will decrease fuel economy, which sometimes is not a factor. It also depends on heavy the right foot becomes.
 
Warning!! More power is a disease with no cure. Also, power and cheap are never in the same sentence. My PSA for the day :thumbsup:

Good luck in your build
 
Depends on the power you want... what i did was put trick flows and a roller came in my 318 with the plan of later doing a 390 and using these heads on it.. kinda of spreading the cost pain out over time :) Point is.. stuff like a intake/heads can always move to a more powerful build later. I am the king of wasting money though.

P.S. you mention buying a shortblock.. if you have money just buy a complete engine from blueprint engines.. no guesswork and drop it in..
 
And remember any mods will decrease fuel economy, which sometimes is not a factor. It also depends on heavy the right foot becomes.
Some mods increase hp & fuel mileage, depends if your gaining power through efficiency or just more fuel. There's a easy 50 hp to get without going all that wild. But I get your overall point.
 
If the engine is 100% stock you probably have a nylon style timing gear. Those gears get very brittle over time and will cause problems. It would be worth replacing your timing set if you do nothing else.
 
Depends on the power you want... what i did was put trick flows and a roller came in my 318 with the plan of later doing a 390 and using these heads on it.. kinda of spreading the cost pain out over time :) Point is.. stuff like a intake/heads can always move to a more powerful build later. I am the king of wasting money though.

P.S. you mention buying a shortblock.. if you have money just buy a complete engine from blueprint engines.. no guesswork and drop it in..
How did putting trick flows and a roller cam (~size?) work on the 318? I ask, because I've got a mechanically sound 318 and a core 360 in the shop corner. What kind of rpm do you spin the stock bottom end up to?
 
My 2 cents- If you have to "save up money" to buy and build a short block I wouldn't personally mess with the present engine that you're not having problems with. Save up and do it correctly or teardown what you have. To me throwing performance parts on a well-used engine without a teardown is asking for headaches.
 
How did putting trick flows and a roller cam (~size?) work on the 318? I ask, because I've got a mechanically sound 318 and a core 360 in the shop corner. What kind of rpm do you spin the stock bottom end up to?
Sadly i'm still putting the car together... so i have only driving it bout 50ft at a time to move it :) Hoping to drive it before winter.. it sounds amazing though... not that that matters....
 
Would cylinder heads with bigger valves
You could add heads like Speedmasters will add performance, plus leave room to grow, but not necessarily needed depending on ultimate goals. You just looking to add decent performance eg.. 250-300 hp or does 350-450+ hp sound more like future plans?
and a performance cam be worth the trouble or should i save my money and buy a short block crate engine? thanks for any thoughts and ideas. i want to have fun with the car but it seems to be a money pit when it comes to making it handle and have power
You could do both or some kind of combinations of these.

You can do a basic hop up for now like 4bbl cam exhaust tune. And save up for something more serious later. Or purchase parts that may not be the best choice for the engine now, like a complete top end that you can put a better short block under at a later date.

Rear end, trans, exhaust are all things that can be modded now and used for a later engine update.

I would go with a 4bbl and mild cam swap, upgrade the rest of the drivetrain and if want more power later get a 360/408 or whatever built.
 
:popcorn: Pull your distributor out and have halifaxhops go through it. He will put a performance advance curve in it and you will notice the improvement even more than a 4 barrel and intake. I would do that first, then a 4 barrel and intake followed by a nice dual exhaust. Stop there because the next step get's real spendy. Cam, heads,headers,gears, converter. And all those need to go together in a specific order or all at once with a well thought out plan or you will be doing some of it over because it doesn't work well with the combination.
Nothing is wrong with my current engine, its a bone stock 318 from 1974. i want to get more power without spending too much money. would it be smarter to put better parts on my current engine or swap it out? i assume the engine has over 120k miles, the odometer broke before i bought it.

Would cylinder heads with bigger valves and a performance cam be worth the trouble or should i save my money and buy a short block crate engine? thanks for any thoughts and ideas. i want to have fun with the car but it seems to be a money pit when it comes to making it handle and have power
 
:popcorn: Pull your distributor out and have halifaxhops go through it. He will put a performance advance curve in it and you will notice the improvement even more than a 4 barrel and intake. I would do that first, then a 4 barrel and intake followed by a nice dual exhaust.
Definitely at least worth doing to this level.

Still think the gain from a small cam upgrade would be hard to pass up, cam or not above is definitely a no brainer.
 
as above run what you have and build as you can afford a better motor. if you can't find a reasonably priced 360 in your area to add a 4" stroker kit to (for 408") then a cheap 318 with the same 4" stroke doesn't give up much at 390". add ally heads of your choice/budget along with cam, inlet, headers and dual exhaust.
those last 2 could be added to the 318 for now so you at least have the 'sound' if not a great hp jump. they'll work better with the bigger motor later.
neil.
ps if you opt for stroking a 318 be ready for all the 'tiny bore' and 'valve shrouding' comments when in reality it's only 90 thou (45 thou all round) smaller than the 360 that they will also tell you you must have, lol.
neil.
 
Last edited:
For a small-engine street car,
like a 318, the Biggest bang for the buck is stall,
with rear-gears a close second.
It's hard to beat 4.10s and .69overdrive; don't even care about stall with those gears.
If you go down the road of engine hop-up, sooner or later you'll be wishing for overdrive. Not just for hiway cruising, but for the big rear gears you're lil 318 is gonna be hungry for.
With a stock low-compression 318,
I don't care how you combo it up, I guarantee you that all too soon yur gonna want a higher stall and/or rear gears. Every time you cam it up, you're bottom end is gonna go away, just a little more. Yur gonna have to stall it up and gear it up, just stay even in the lower half of the rpm band, where your sweet 318 is gonna be spending most of it's life; cuz if you don't, pretty soon it's gonna be nothing but a weekend warrior, and a miserable gas-guzzling pos hiway cruiser, parked in the carport.
Do yourself a favor stall; it up first, then gears; You'll never be sorry.
-----and then overdrive; now even less, not sorry.
-------then a 4bbl and hi-flow exhaust; now we're talking!
-----------Then, finally, yur ready to begin sacrificing cylinder pressure.

Or you could just pump up the compression first to match whatever cam you have chosen; Then stall it up, and gear it up, and so on, and then several thousands of dollars later, in goes the overdrive.
And then, you get an epiphany;
with 4.10s and a nice convertor, now yur just roasting the tires. You might as well give up a bunch of power cuz all it's good for is roasting said tires and sucking gas; and with the chassis as it now stands, you couldda done the same or at least not much worse, with say 250hp.
Ok hang on, that's about what a stock low-compression318 makes, with a 4bbl/hi-flow exhaust, and a tune.
If you keep your car long enough, you will have talked about overdrive, for nearly as long, and until it goes in, you'll be wishing you had installed it a loooog time ago.
Ok well, that's been my experience. lol.

If I was to start a 318 project today, knowing what I now know, over 50 years since being a teenage hi-school drop-out, the overdrive would be my first mod; followed hotly by probably a 3.91SG.
Then I'd plug a stock 5.2 in there, or a 9/1 LA, with a 5.9 type cam, headers, Free-flo exhaust, a small 4bbl, gotta have FRESH AIR, and call it done.
And this time Ima running short Cherry-Bombs! Hellya!
 
i guess it all depends on the end results you are after.. for me, i would throw a 360 in the thing.

if you want to keep the 318 you can do an intake and carb, work i=on the timing curve, rear gears, converter, headers, samll cam. depends where ya want to go and what you want to sacrifice.
 
Last edited:
as above run what you have and build as you can afford a better motor. if you can't find a reasonably priced 360 in your area to add a 4" stroker kit to (for 408") then a cheap 318 with the same 4" stroke doesn't give up much at 390". add ally heads of your choice/budget along with cam, inlet, headers and dual exhaust.
those last 2 could be added to the 318 for now so you at least have the 'sound' if not a great hp jump. they'll work better with the bigger motor later.
neil.
ps if you opt for stroking a 318 be ready for all the 'tiny bore' and 'valve shrouding' comments when in reality it's only 90 thou (45 thou all round) smaller than the 360 that they will also tell you you must have, lol.
neil.







valve shrouding'comments/haters when in reality it's only 90 thou smaller than a 360.
Less with a overbore.
 
To me there's two main ways to look at a performance build.

1st, build to a certain hp, and for the most part a 318 is basically just as capable as other engines for the general hp most build to, but generally you need more rpm and all that comes with it, stall, gears, idle etc.. Which may or may not be a problem.

2nd, is to build a certain rpm band, in the street generally 2000-5000/6000 rpm, with peak power in 5000-6000 rpm which can make huge difference to the engines behavior and power. But whatever rpm range your gonna build to. It's gonna have a typical hp to cid ratio varied by efficiency, obviously larger displacement are generally gonna make more power at those rpms especially if talking similar efficiency, but will need a lot more cylinder head etc.. to do it.

Basically if you know roughly the Hp you want and at what Rpm you want to peak at and how efficient (lbs-ft:cid) you can build it, basically gives you the cid you want.

Cid = (hp x 5252 / rpm) / (.9 x lbs-ft per cid )

1.2 lbs-ft:cid can be used as a general build (cr cam 4bbl headers)
1.25 lbs-ft:cid if aftermarket heads, roller/bigger faster cams etc..


Eg..
400 hp @ 6000 rpm, 1.2 lbs-ft = 324 cid
400 hp @ 5500 rpm, 1.2 lbs-ft = 354 cid
400 hp @ 5000 rpm, 1.2 lbs-ft = 389 cid
 
Last edited:
i want to have fun with the car but it seems to be a money pit when it comes to making it handle and have power
some how i missed this part on the first go around.

these mopars can be made to handle quite well for not a lot of money. upgrading the stock components is cheap and easy and yields great results for not a lot of cash.

but yeah, all old cars are a money pit.
 
For cheap ish handling sway bars, shocks and tires.
Your unlikely gonna take corners fast enough to out do these mods, torsion bars and leafs are obviously the next upgrade and become more important if you lower it.
 
-
Back
Top