I've seen A LOT of posts about making HP with a 318-So why is it so ???

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Once upon a time if you had a 318 it was the budget option versus buying something else.
But now 5.9 magnums are an average of 350 bucks running. You cant hop up a 318 to match it for that money. It also takes so much less skill to swap an engine for newbies than it takes to hop one up.
The only reason i see to hop up a 318 is for fun or if you score some sweet swap meet deals on pieces.
 
You still need a intake carb, ignition, and exhaust to make it happen. Yes there are pro's and cons.
 
toolmanmike said:
You still need a intake carb, ignition, and exhaust to make it happen. Yes there are pro's and cons.
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Agreed. However you need the same stuff for the 318. LA intakes are cheaper and available used. Everything else is the same cost.
 
The only thing that costs more for a 318 is pistons.
 
422 horse-398 lb/ft Engine specs sketchy but +.040 teen, 11:1, Ported EQ heads, Hydraulic FT 230/236 112°

 
James Clews said:
What sort of HP do you think my teener will make? I have a 1980 CM Chrysler Regal SE (the last of the Australian built Valiants) The 318 will be bored 30Thou with KB pistons (approx 9.7 to one comp) Summit 6901 cam 218/228 470 lift(1.6 roller rockers) 114 lobe centre, Procomp fully ported alloy heads flowing 285cfm on the inlet and have really good low lift numbers, Exctractors running into dual 2.5 inch system Wiehand alloy dual plane intake with 650 AVS2 carb , Factory cold air induction. You may ask why am I doing this with a teener? I have a 410 Charger that runs low elevens and am restoring this lovely Regal with the factory 318 and am using most of the left over parts discarded over the years from my 410 Charger. The car will probably never see a drag strip but will be just a cruiser as it only has 77 thousand kays on it(About 48 thousand miles) and was parked since 1995. Car is fully loaded with air, steer , elec windows etc. Has Factory 727 auto and 2.92 diff. What sort of HP would you think this should make? Why not put a 360 in it? 1 it is the numbers matching motor . 2 petrol in Australia is $1.60 @ litre ($6.50 a gallon)Yes costs nearly $120 to fill up now days but yes I believe our tradesman wages are a lot higher than the US wages.
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I built a 318 with zero deck, 10:1 compression .043 quench with a comp XE268H and indy LAX heads worked by brian @ IMM. Eddy airgap, 750 double pumper. Ran a 12.96 @ 103 1/4 mile with 3.73's in stock form. Dyno'd at 286 rear wheel horse and 268 rear wheel torque IIRC. Not bad for a teener...yours will probably put out higher numbers. Great motor and I've still got it on a stand playing second fiddle to my 408.
 
But now 5.9 magnums are an average of 350 bucks running. You cant hop up a 318 to match it for that money.
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The down side is, you can be pretty sure the factory heads will be cracked........... and from what I understand the “good” performance enhancing EQ heads aren’t available anymore.
I’m not hearing great things about the Chinese made Magnum replacement heads, and I don’t think the MAX heads are currently available either.
So, there are no “cheap” head upgrades to replace those cracked factory pieces that I’m aware of.

The short blocks are usually in good shape from what I hear, so converting to LA heads with pushrod oiling might be a good option if that type of top end is within the budget.
 
IDK who you quoted with this statement below;

But now 5.9 magnums are an average of 350 bucks running. You cant hop up a 318 to match it for that money.
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But you can hop up crap for that price.
 
rumblefish360 said:
IDK who you quoted with this statement below;



But you can hop up crap for that price.
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Yep, that's why I mentioned above all the parts you need to make a Magnum happen. If you need to buy a intake and carb, ignition and exhaust to make a Magnum work in your car why not just put those pieces on your teen that's already under your hood. Magnums are better but at what cost!
 
The only real viable magnum replacement head available currently are the edelbrocks, at about 2k or the trick flows. The trick flows require a certain rocker setup to oil through pushrods however.
 
Anybody drill the block for LA head oiling? I have read about it done but have never known anyone to do it. Measure twice, drill once!
 
Comp makes an affordable rocker to oil through the pushrod, as well as PRW and Mancini. Early Magnums (I would guess pre '94 or '95) had the head oiling passage from the factory.
 
toolmanmike said:
Yep, that's why I mentioned above all the parts you need to make a Magnum happen. If you need to buy a intake and carb, ignition and exhaust to make a Magnum work in your car why not just put those pieces on your teen that's already under your hood. Magnums are better but at what cost!
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Here’s why I mostly disagree;

It’s that the LA & Magnum as delivered come a certain way.
Most LA engines with 318’s came as a 2bbl.
Converting a Magnum to a carb will require the same parts. The intake prices for a Magnum brand new vary a lot. Not so much for the LA which is generally cheaper as new from Edelbrock or a used unit vs a used Magnum.

So a price comparison can be an extensive writing. Anyone thinking about this should price shop down spend wisely or just throw caution to the wind vs the wallets same and just get the brand spanking new Edelbrock.

But each engine so far just needed a 4bbl. carb and intake. Only brand new OOTB the Magnum costs more from 1! Manufacturer... The knock offs are so cheap that argumentation is crazy and perhaps you need a better job or another hobby.

The price of cylinder heads also falls in like the intakes.
Be it a 318 vs a 360, LA vs a Magnum, stepping up from the OE head is a cost you have to ether price shop for the cheapest or just go out and get the expensive head. Being that the trick flows, which IMO are the best bang for the buck in terms of return performance on the dollar spent while fitting both engines. Being that’s the fact of the head, if I were starting a engine from scratch now, that would be the only head choice I’d consider for the street, street strip machine. By the time you purchase and then port the Edelbrock head, (not doing it yourself) your paying about the same as a trick flow. Of course if the cheaper Edelbrock fits the wallet or build, then that’s fine as well. Choose your parts well.

On camshafts, each need a upgrade for performance unless that whooooping factory rated engine’s HP is good enough.... lmao...

The Magnum can just get away with just a cam purchase on a lot of levels.
The LA can also but also requires lifters with the cam. Still cheaper than just the roller cam but the performance spec vs spec being as close as the same as possible .... makes the HFT a LOOOOOOOOOSER....
 
toolmanmike said:
You can get 300 horse out of a teen pretty easy and with good heads and some compression (and all the rest of the goodies) 400 horse isn't out of the question.
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Here's a stock low cr longblock with 4bbl headers and a comp xe262h cam making 282hp @ 5000 rpm, up the cr and probably hit 300hp then add xe268h-xe285h + for even more power before doing anything with heads.

I wonder what a 10:1 stock head no porting 318 would make with a comp xe285h or similar cam airgap 750 and headers would make ? my guess would be 330-350 hp at 5500-5700 rpm. Heads would definitely be the limiting factor.


318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
 
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If your car has a good running 318 or you already have one to put in your car, definitely worth small ish cam 4bbl and headers or just duals 250-300 hp, after that it's hard to do more for most, most aren't gonna port heads and swap to higher cr piston so limits what can be done and if your rebuilding it is worth your time to dig up a 360 block but if not no reason you can't make power that you could do with an average built 340 just at 300-500 rpm more. Could also throw on aftermarket heads on a stock short block with a xe268h ish cam and airgap and come up with decent power and have the parts for a future build.

But I agree the best bang for the dollar is to find a running 5.2l/5.9l Magnum and add 4bbl for 300 + hp add cam and headers for 350-400 hp.
 
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What HP does it take to run low 8's in the 1/8mi and high 12s in the 1/4mi in a '68 Dart with a 727 and 4.30 gears? That's what a stock bore and unported heads '93 Jeep Grand Cherokee 5.2L/318 did back when the M1 dual plane and single plane were all that was available for a carb conversion (late '90s). I used the single plane because of the gearing, but I had a dead "175K" MoPar converter in there (2400?) and a dreadful 60ft time. The engine screamed 3000-6500+ and everyone thought it was a 340. So they can run pretty fast in Magnum form, they are just ignored for the 5.9L/360 Mags. Back when I did it, it was harder to get a 5.9 and this one was basically free, a good warranty core from a "smoking" Jeep, and the breatsplate gasket on the kegger intake was just sucked in.
 
After reading a few pages of interaction here, and looking at my own 'B/RB/G3 Hemi' bias - I don't see an issue with a 318, if expectations are kept reasonable.

Expectations low, meaning 230 - 260 HP @ 5,000 RPM is a good place to start. We aren't talking about 'trick' builds to make this power: stock 7.5:1 CR (original engine) with a near factory replacement dual-plane (Edelbrock Performer), 600 - 650 Carburetor (Edelbrock or Holley), Small camshaft (215 - 230* @ .050 / .450" lift / 110-114 LSA), Longtube Headers, & open exhaust.

The same can be done to a 5.2/5.9 Magnum to make slightly more power, but they are getting to be near 30-years old as well. Most of these engines are worn completely out, will need a rebuild, and some (not all) have at least one cracked cylinder head. The bottom end might be fine however, but really it's the cylinder heads that were trouble on a lot of these engines.

We built a near identical engine to the above in a prior-MIL M880 Dodge (1977 W200) truck. I can tell you, it's an incredible difference overall in power over the factory 2-barrel setup with manifolds. We didn't touch the cylinder heads, only installed new valve springs.

Of course, anyone wanting to make more power with a 318 LA, would run a SFT camshaft around 235* @ .050 / .480-.500" lift / 108 LSA and a RPM Air-Gap manifold. I'm sure that would get 280 HP out of this combination and have no problem running with most 340's and 360's of this era. Lets be realistic, most of these original LA-engines are losing around 6% overall in power due to compression ratio alone, compared to a 9.5:1 typical (rebuilt) street engine with iron-heads.

A lot of people also need to keep in mind, that although these engines typically don't make a lot of power (especially compared to modern vehicles), they can still have a great power to weight ratio. You don't need to make 350-HP to have a nice, street driven car or truck. The lack of torque at lower engine speeds, allows most of the driveline parts to last for a very long time.

1977' Dodge W200 'Power Wagon' - 4,500 lbs w/ 250 HP (NET) - 0.0556 hp/lb
2015' Ram 2500 'Power Wagon' - 8,000 lbs w/ 410 HP (NET) - 0.0512 hp/lb
 
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