How do I get more power out of my 318?

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Dead Reckon

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318 LA
So here's the deal, I have a stock 318, in a mostly stock 1984 Dodge D150, and simply put, this V8 would make the Warboys of the Mad Max universe laugh, or cry, or both. It's got vacuum issues, I need to check the distributor advance, and I feel like the only reason it's running at all is because the previous owner put a cap, rotor, plugs, wires, and an ignition control box on it.

I am replacing the timing chain and redoing the exhaust soon. The timing chain will be replaced by a Sealed Power CTS3000 kit, and I'm planning on going for a high flow cat and Cherry Bomb shorty glasspack in 2.5 inch exiting out in front of the passengers side tire.

I know these two things alone will wake the engine up, but how about a 4bbl intake and Holley carb? New distributor too? I don't like rebuilding distributors. Are factory 4bbl Thermoquads any good? I know someone who rebuilds carbs, so a used one is probably gonna be the solution. I know with GM the Quadrajets are loved and hated equally, I always liked the absurd secondaries kicking the crap out of the engine. But I know nothing about the Thermoquads. Or could I go cheaper and slap on a 500CFM 2bbl that's a bit better? Is the mounting pattern for a Chrysler intake standard size?

So yeah, in short, I want more power out of this engine, how do I make more power? Headers are a no go, not spending that kind of money on them or a mini starter.

Thanks in advance, I got up to some shenanigans in my '77 Olds, and this truck ought to fill that void nicely if I can just wake the 318 up, it feels like it's sleeping. Fuel economy, who needs it? Power and noise, that' the way I like 'em.
 

crazzywolfie

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if you are replacing the timing chain and possibly changing the intake spend the bit extra and swap out the cam. an RV/towing cam would even make a stock 2 barrel a bit more responsive.

as far as vacuum lines go you should go through them first and make sure there is no leaks and possibly remove any unneeded lines. you can test the vacuum advance on the distributor. if it is working properly and you have a 4 pin ignition system then i would probably leave it alone.

as far as carbs go i am personally a fan of the holley 4 barrels for how big the float bowls are. they deal with the heat way better than the other brands. i got a 670cfm holley street avenger on my 81 but i got it leaned out and it still wastes fuel. also have you possibly considered EFI? summit has some fairly cheap kits. you can get a whole setups from FiTech for under $1500 and their kits are pretty good. the computer even has the option to control electric fans if you got them or plan to get them.
https://www.summitracing.com/int/parts/fif-30003/overview/
https://www.summitracing.com/int/parts/fif-40003/overview/

also if you want a mini starter you are best to buy one used at a auto recycler. you can get them cheap off any 88-98 dodge with a 239, 318 or 360. they are super cheap and easy to fix if it does need work. only thing that ever has issue with time is the contacts in the solenoid. they also make removing the starter in the future so much nicer
WC99CnZfBVfRA_1d8CjudR3Uh_aPreDVeq_NvcE4ZDvUPAy2sIxR4j3Catsr7EdbZTlAh-2ujIJCtw=w1366-h768-rw-no
 
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Dead Reckon

Dead Reckon

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I've decided I'm gonna give a Edlebrock carburetor a try, 500CFM. You mentioned headers, I can get a new ministarter for a 94+ Dodge Ram 318 for around $100 new, or 80 rebuilt. What headers fit the best for $250 or less? Gotta keep the budget down 'cause I gotta have an exhaust shop make a crossover and X pipe. It's just a thought, nothing decided yet on the headers, if I don't get them I'll get a new walker Y pipe to delete the pre-cat on the drivers side.

Not gonna cam it, don't want to risk it, the heads didn't look too great when I go tthe valve cover gaskets done the other day. Lots and lots and lots of flaky buildup. The head bolts where buried in it.

Sorry for the delay, and thanks for the input, probably selling my Buick tomorrow, so I can get my truck on the road and maybe pick me up another gun at the Hillsville Fleamarket / Gun show this labor day weekend. Fun times!
 

crazzywolfie

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at least your not over carburating the engine like most people do. you could try contacting an auto recycle and you might be able to get a mini starter cheaper from them. i don't know which header will fit perfectly. i think most usually require a bit of beating to make them fit. the big thing is to compare the flange thickness. i think the cheaper they are the thinner it is and the more likely you are to be battling with exhaust leaks in the future.

without a cam you won't get the most out of the other upgrades. i am pretty sure summit even sells a rv/towing cam/lifter kit for cheap.
 

84lamb250

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If the heads are not looking great... you could get more power by going with the magnum head conversion, they have higher ratio rockers and are better flowing. You could pull off a set in a junkyard, but be warned, most of them are probably going to be cracked. They tend to get hot spots, so it may be hard to find a good set of magnum heads. Or you can play it safe and get some new aftermarket ones. Just make sure you get oil thru lifters/pushrods and such, takes a few changes to convert.
 

Sniper X

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Yes and RV cams are not for power, they are for mileage only. A while back a guy talked my buddy into putting one in the 440 in his ramcharger for better mileage, it only got about 2mpg better than the 440 Magnum cam, and lost what felt like half the power.
 

crazzywolfie

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well you can either have good mileage or lots of power. it is hard to get both especially with something like a 440. from what i have been told RV cams usually wake up a stock 318 pretty good

personally i wouldn't recommend putting magnum heads on an LA block. do a complete engine swap if you want the better flowing heads. don't do half a job. then you don't have to **** around with mix matching of parts especially if you have stuff fail on you.
 

Sniper X

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I doubt anyone thinks they can do something impossible, buld big power on a no power motor. Unless the 318 was a performance 318 out of say a Plymouth or Dodge Stinger or Swinger or Dart GT, it is not going to make big power unless one spends a ton of money on it. The only way to do it right it a good set of aftermarket heads or super expensive 340 heads, and a quality cam and lifetrs, headers, carb, intake and so on and so on. IF you just want to make BETTER power than a tired ass old 318 has, that's easy. Have the stock heads rebuilt with a 3 angle valve job and new guides, possibly even shaved for a little more compression, get a set of ****** headers, Edlebrock intake, a medium street strip cam say about 280 degrees of duration. And possibly even bore the motor .30 over and buy a set of 10:1 pistons. You MAY see 300hp. Possibly even more.
 

CC12RamLove

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I grew up driving my dads b150 van with a 318. 360 intake manifold and a holly 4 brl and fuel pump and a beefed up cam and updated electric ignition. Decent gains. Finally we ripped it out. Full build. Block bored and balanced heads done with valve job, new cam carb and msd ignition system. Would rip the 305 tires off. Pops put some money into it but it was a solid engine.

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Jimmy68

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This is such an easy job to do and it seems to be getting lost and confused in conversation.
Yes, it all costs money. But if your at the chain swap then put in a nice cam and lifters. Unless you just can't afford them.
4BBL is nice and a nice Edelbrock perfomer RPM manifold would be nice.
I happened to use a stock 4BBL manifold (hard to find now) and a wrecker 750 Q-jet off a 350. Nice and cheap. I had a 360. But a Q-jet off a 305 or 307 will fit the bill for you. Q-jet came stock as 500cfm/750cfm and 800cfm (hard to find, off some Big blocks).
Heddman headers are nice and fit well without modification in my old truck. Quality was good and price was $200 at the time.
Mini starter is like $60 at the wrecker.
All done your still looking at several hundred bucks by the time your done.
 

crazzywolfie

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heck i picked up a stock 4bbl intake and carb last year for free. i didn't need it but i wasn't going to turn it down.
DxM3X812zTtzmAhV1O0l80kkUybnqpna4LGfA=w418-h638-no.jpg
 

Sniper X

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This is such an easy job to do and it seems to be getting lost and confused in conversation.
Yes, it all costs money. But if your at the chain swap then put in a nice cam and lifters. Unless you just can't afford them.
4BBL is nice and a nice Edelbrock perfomer RPM manifold would be nice.
I happened to use a stock 4BBL manifold (hard to find now) and a wrecker 750 Q-jet off a 350. Nice and cheap. I had a 360. But a Q-jet off a 305 or 307 will fit the bill for you. Q-jet came stock as 500cfm/750cfm and 800cfm (hard to find, off some Big blocks).
Heddman headerare nice and fit well without modification in my old truck. Quality was good and price was $200 at the time
Mini starter is like $60 at the wrecker.
All done your still looking at several hundred bucks by the time your done.

We know, but the problem always is the same. Someone asks about replacing a cam for more power and the rest of the motor is stock, so ensues the conversation of you can't get there from here. I've been involved in these discussions since I got my first car in 1974, a Chevelle SS with the 375 HP 396, and all my buddies who had bought small block Chevys or mopars all asked the same question. Back then it was a little easier because most small blocks at least had higher compression, and better flowing heads a d came stock with a 4 barrel.
 
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Yeret

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Magnum cylinder heads would be a nice improvement, however an improved-design set that won't crack between the valves will run around $600, not to mention the cost of converting the block to accept the heads. They'll bolt on just fine, but the valvetrain oiling is very different between a Magnum engine and an LA engine. If you simply bolt a pair of Magnum heads onto an LA block without proper conversion, you will destroy the valvetrain very quickly.

You note that your distributor advance isn't functioning correctly. This will yield similar results to the "death flash" on the Magnum engine. In other words, the harder you try to accelerate, the "heavier" the boat anchor that is now your engine becomes. Fix this or you will never realize anything that even remotely resembles performance.

Other vacuum leaks? Any single vacuum leak can screw with how an engine performs, let alone what several will do. Fuel-injected engines can adapt to small leaks depending on where they are. A carbureted engine can't detect and adjust to any leak so even a small leak could lean out your mixture.

Factory engine? Exhaust "upgrades" won't net you much if anything at all. It's actually quite easy to kill your low-end power while picking up miniscule top-end gains by fiddling with the exhaust. DO NOT fall into the "true dual straight pipe" trap. Sure it looks cool, but there is no easier way to 1. kill your low-end torque, 2. make your truck sound obnoxious as hell. Stick to a single exhaust with slightly upsized pipes all around and you'll pick up some mid-range without significantly affecting low-end. Summit offers El Cheapo headers for Magnum heads for $200 and these are a direct fit on LA heads. Nevermind the gaskets that come with them, spend a little extra for quality gaskets and you'll thank yourself later.

Good choice on the carb. As wolfie said, it's nice to see that you aren't trying to "overcarburete" the engine. That cfm rating sounds appropriate for a mild 318.

No cam? No good. If you're gonna swap to a four-barrel and appropriate manifold and open up the exhaust, that "sausage" grind is going to bottleneck the entire setup. The later Magnum OEM cams were pretty soft, but they were still good enough to generate 245 horsepower. Your setup is rated for 140 horsepower, so I can only imagine how soft the cam is in that.
 
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