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  #1  
Old 06-09-2010, 02:00 PM
86FifthAve 86FifthAve is offline
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Default Making more power out of my 318

Okay, so I have a 1986 Chrysler Fifth Avenue with a 318. I really want to make this thing into a sleeper. I need some good tips that are easy to do and not too expensive to make her a little more powerful and faster?
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  #2  
Old 06-09-2010, 07:55 PM
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bulldog426 bulldog426 is offline
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so what kinda budget?? i'd say get some 360 magnum heads, some speedpro pistons, to bump up your compression, and the magnum heads will also help compression plus they flow nicely, aftermarket cam i'd try the lunati or comp 268, the lunati is a little bigger than the comp, 4bbl intake, preferbly an edelbrock performer rpm, or a weiand stealth, and throw on a shot of nitrous esp if you get the forged speedpro pistons, nos is usually the best way to get power out of a sleeper, doesnt sound as radical when people see it, plus you don't kill your fuel mileage when driving around plus it's alot cheaper than forced induction, but thats just me, i'm a nitrous junkie so to speak...
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Old 06-09-2010, 11:43 PM
86FifthAve 86FifthAve is offline
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I mean really tight budget ha ha. I have some money but I need to do stuff slowly. Would those 360 Magnum heads need to be ported?
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Old 06-10-2010, 01:25 AM
rampage_82 rampage_82 is offline
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The Magnum heads should work fine on a 318 without porting, however you will need oil-through pushrods and the pushrod tunnels might need to be clearanced for a flat-tappet cam. Also the intakes can be hard to find, unless you get them redrilled.
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Old 06-10-2010, 11:16 AM
340_GTS 340_GTS is offline
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You are on the right track... get rid of the Lean-Burn sytem by putting in a normal distributor and spark control box, and finding a good used 318/340 4-bbl intake and something like a 600 cfm carb. Almost anything is better than what's on it now. Next thing would be a good dual exhaust system, and then headers or if you can find them, the good 340 exhaust manifolds. Heads and any other serious stuff should come later.
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Old 06-10-2010, 01:41 PM
86FifthAve 86FifthAve is offline
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Would I be able to put a normal ignition system on without replacing the carb? Because I do believe that the carb is electronically controled by the Lean Burn system. I found a Proform Electronic Distributor conversion kit for $145 would that require a conventional throttle body carb?
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Old 06-10-2010, 11:49 PM
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bulldog426 bulldog426 is offline
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yeah but you wont make much power with that little bitty 2bbl that came on the 318s, and summit makes the intakes that will fit both magnum and la heads, so if you want to keep your heads for now and go to the magnums later you can still use the same intake. and they also make the right pushrods for this swap as well, but the magnum heads would be good to go as far as the ports, i would get em shaved just to boost my compression up..
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Old 06-11-2010, 09:47 AM
chirorod chirorod is offline
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Default 86 5/a power

actually, I think the heads on the 318 are pretty good. if you're on a real tight budget, you might not want to have the heads re-worked. you can get more power by having the 1.88 or 2.02 intake valves fitted. a used 4bbl manifold and carb will make a huge difference. to get rid of the lean burn, you need a distributor with vacuum and centrifugal advance, which you might be able to score off an older small block. if you get one off an older pu, you can put in an advance kit. the lean burn distributor has no advance, because the computer controls the timing. then you need an ignition system. the stock coil might be good enough. you need either a mopar box and ballast resistor or gm hei module from a 70's gm. the gm is unbelievably easy to wire and shouldn't have any heat problems if mounted on a heat sink on the fire wall and costs less than $40. you use ported or non-ported vacuum advance. I think non-ported works better. set initial timing to about 14 degrees btdc with dist vacuum blocked. check for 34 or so degrees full advance. you'll have to make your own kickdown or find one off a 4bbl. you'll have to find an air cleaner that gives hood clearance.
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Old 06-15-2010, 08:57 PM
86FifthAve 86FifthAve is offline
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Wow. That would help a lot actually...the only problem is this car is my daily driver and Idk if I can afford to take the heads off unless I can manage to do it all in one day.
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Old 06-15-2010, 09:46 PM
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got a set of heads,intake, distributor that I took off a 360 that id let go cheap. I needed a block. carb to, but needs to be gone threw
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  #11  
Old 06-16-2010, 12:44 AM
DartGT66 DartGT66 is offline
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Factory 318 4 barrell engines used 360 heads with 1.88/1.60 valves. The power difference ebtween the 2 and 4 barrell versions was something like 10 hp. Your 318 may have the more desired "302" heads, those ported and equipped with bigger valves perform pretty well. Still, a 318 or 360 magnum heads (they are both the same) are way better and have big valves stock, should be an easy find from the junkyard with complete valvetrain and valve covers, and also the lifters and their support sturcture. Might also consider the exhaust manifolds if they fit your chassis. While at it, might be a good point to do something for the compression ratio, which typically is very anemic in the 318's. I believe your engine is alredy roller cammed, a double roller timing chain and a mild reground performance cam from Hughes. Those together with a professional rpoducts intake and a 600 cfm vacuum carb, performance exhaust + the forementioned distributor would make a stouot 318. And with careful shopping shouldn't cost that much.
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  #12  
Old 06-16-2010, 07:39 AM
chirorod chirorod is offline
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Default making more power

sounds like you don't want to do any engine tear down. therefore, you wont be able to do anything about compression ratio. the heads are probably 302s, which are fine. just that they have the small valves, which you can get by with. but you pretty much have to ditch the lean burn carb and system. remember that if you have rigorous emission testing, you can't do much of anything that helps the horse power. also, the stock cam is gutless. just enough lift and duration so it runs. this is probably so you cant burn enough gas to pollute. the stock timing chain is the plastic lined type, which is usually pretty well worn and stretched by 60k. the stock cam is a roller type. replacing a roller is more expensive than a flat tappet cam. you can put a flat tappet cam in it, but this means flat tappet lifters and pushrods, too. the stock rockers might be ok if not worn. I put a summit 6901 cam in mine. this doesn't have a lot going for it but huge improvement over stock. I also used a tq carb off a 76 360 and iron manifold off an 81 Dodge motor home 360. I cobbled up a distributor that has vac and centrifugal advance. using a gm hei 4 prong module. has pretty good oomph despite the 2.24 gears. wont, of course, light the tires.
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  #13  
Old 06-16-2010, 07:52 PM
cudabob496 cudabob496 is offline
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synthetic oil, a good tune up with new plug wires, and somekinda cold air
induction will get you 30 hp!
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  #14  
Old 06-17-2010, 12:29 AM
dodger1 dodger1 is offline
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Quote:
Originally Posted by 86FifthAve View Post
Wow. That would help a lot actually...the only problem is this car is my daily driver and Idk if I can afford to take the heads off unless I can manage to do it all in one day.
You're not gonna do all that in one day. Unless your shop is fairly well-equipped, and you've done ignition and fuel system mods in the past, I'd recommend starting with the ignition re-work (either a Mopar electronic retro-fit, which will need a distributor, ECU, and some wiring mods, or the GM HEI mod) You could get that done in a day, preferably Saturday, and get the bugs out on Sunday. Stage 2 would be bolting on a mid-70's - early 80's stock truck iron intake and Carter Thermoquad. After you find the donor truck, and get all the throttle and K.D. linkage, go through the carb (carb kits are still available), get your new intake gaskets, and you should be able to install that on a weekend. This is the cheapest way to upgrade the 318, unless you have access to a used aftermarket carb and manifold. (The iron 4barrel and TQ can make some pretty good power - I use them) You'll still be limited by the stock cam and low compression, but those mods can come later. I agree with chirorod on the possibilities, but if this is your first try at this, trust me. I've got the t-shirt. (Also, get your hands on a Factory Service Manual for 1978-80 rear drive cars - they have both leanburn or ESC and the earlier electronic ignition info and wiring schematics which makes things simpler by far)
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  #15  
Old 06-17-2010, 11:34 AM
86FifthAve 86FifthAve is offline
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Well how much would this cost about? And will this murder my gas mileage? lol and does anybody have any good cam suggestions? I'm just getting into the upgrading world, I fix things but this is the first project I have gotten into that I am trying to change things up rather then put it back how it was, so I have no idea what to look for.

And my dad can help me with the ignition and all he removed a Lean Burn before. So most of the problem is the head work. He would help me but a lot of it is getting them shaved down and back fairly quickly. I have accuses to all the tools I will need though, its just parts and money

And I found headers that will fit off an E body and I guy who will put them in and do an exhaust system, but will the Headers fit if I got the heads shaved down?
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Old 06-17-2010, 07:23 PM
rampage_82 rampage_82 is offline
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Yeah the headers will still fit, because you're only taking off thousands of an inch. As far as the cam, I would suggest that you try to find a regrind for your Hyd. Roller, you can get them very inexpensively and it will make much more power over the Flat tappet stuff, and you don't have to worry about it going flat.... Just my thought... Also if you get everything right and make the motor efficient I wouldn't be surprised to see an increase in fuel mileage...
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  #17  
Old 06-17-2010, 09:41 PM
chirorod chirorod is offline
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I was looking at the roller I took out of my 86 5/A. It looks like there might not be enough meat there to regrind. What do you think? I agree that the roller is a better idea for long life and no need to use zinc additive, but I am wondering if the stock roller cam can be reground.
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Old 06-19-2010, 01:37 PM
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Would there be enough $$ saving between a re-grind and a replacement cam from one of the reputable suppliers? Plus, having the new cam in hand before dis-assembly will save time.
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Old 06-19-2010, 03:15 PM
rampage_82 rampage_82 is offline
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Well usually you can get a regrind roller cam for around $150, whereas a Comp, and several others are $300+... Check out this Hyd Roller regrind from Hughes see what you think.... http://www.hughesengines.com/Index/p...=&partid=11433
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  #20  
Old 06-19-2010, 10:32 PM
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Why not just buy another 318 or 360 build it and swap it in on a weekend. You can pick them up running for $100-200
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Old 06-20-2010, 06:41 AM
cudabob496 cudabob496 is offline
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Why not just buy another 318 or 360 build it and swap it in on a weekend. You can pick them up running for $100-200
where would you pick them up?
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  #22  
Old 06-20-2010, 11:41 AM
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If you're sticking to the tight budget, I would say re-building a motor would not be in the cards. Anything you do is going to take more time than you will plan, so use the weekends. Start Friday evening. Should be able to do the ignition in one weekend. The next weekend, cam, manifold, carb. If you haven't done a lot of these, the cam, manifold. and carb might be a bit much for a weekend. There can be a lot of customizing involved, especially carb and kickdown linkage. If you are pretty quick, no sweat. Changing the cam requires pulling the manifold, anyway. The roller cams are at least 3 times the price of the flat tappet. Hughes cams would require probable changes in the valve train. But using a flat tappet cam requires push rods and lifters. The roller lifters are very different and a lot taller. A flat tappet cam means longer push rods. I was lucky enough to score the push rods off the Dodge motor home I took the manifold off. That motor looks absolutely clean inside and no visible wear on the push rods. You are also going to need a timing chain and gears, because yours is worn. But that is part of the cam job anyway. One word of caution: you might want to go with a holley, edelbrock, or quadrajet carb. The thermoquads can be hard to do. It took me 3 teardowns on mine to get it right. The idle circuit is a tiny passage inside the primary passage and very hard to clean. There is a learning curve on them.
The holleys and edelbrocks are square bores, so you would have to get an adapter, which is cheap, if the manifold you find is a spreadbore. The qj is a spreadbore. Also, you have no way of knowing if the carb you find is ok until it runs. There is a lot of junk in gasoline which settles out in a carb which sits. Most of the time, it's the junk in the gas which causes trouble. The passageways inside the carb are very small and easy to plug. Good filters stop suspended particles, but the refining process leaves in a lot of things like varnishes and shellacs, which don't do much harm until the carb sits for a few months. And this is often what you get with a used carb.
You can get a lot of power without spending much, if you can get good prices from someone on the forum or from a local salvage yard.
For some background, check tech articles from magazines like mopar muscle.
I think it's important to remember that when you customize, it can take more time than you plan.
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Old 06-20-2010, 12:36 PM
rampage_82 rampage_82 is offline
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The link to Hughes I gave above is for a regrind cam. It can use all stock components I.E. Lifters, Springs, Pushrods, Rockerarms, and being a small block you will definitely want to replace the Timing set anyways... This cam is $199, which is a little more than a flat tappet, but there is no break-in worries and it will last forever, plus make more power than a flat tappet over a broader range. Basically you pull the intake, rockers, pushrods, fuel pump, and lifters. Slip out the old cam, put in the new one with a new timing set, put everything back together, and forget it, instant 50hp.. If this one is too big and scary they also have this smaller one http://www.hughesengines.com/Index/p...d&partid=11430... you will also need to check pushrod length and will probably need a little longer pushrod, because of the smaller base circle that comes with a regrind...
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Old 06-20-2010, 10:58 PM
86FifthAve 86FifthAve is offline
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Well if I do it during the Summer I can drive the old Charger around for a while so I guess I can do most of this! Thanks for all the help! If you have any other suggestions please let me know!
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Old 06-21-2010, 06:33 AM
DartGT66 DartGT66 is offline
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Just pay attention that you need a magnum cam core, or it's 100$ more. And I'm not sure wether the magnum cam requires an electric fuel pump or not, since they dind't have a provision for mech. pump stock?
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  #26  
Old 06-21-2010, 07:31 AM
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Quote:
Originally Posted by cudabob496 View Post
where would you pick them up?
Just look on Craigslist. There were several 318's in the minneapolis area for $100-200. I just picked up a 318 and 904 last friday with 53,000 miles in duluth, mn for $150.


Huges Engines has a kit for to add a fuel pump eccentric to a magnum cam.
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Old 06-21-2010, 08:27 PM
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Originally Posted by chirorod View Post
If you're sticking to the tight budget, I would say re-building a motor would not be in the cards. Anything you do is going to take more time than you will plan, so use the weekends. Start Friday evening. Should be able to do the ignition in one weekend. The next weekend, cam, manifold, carb. If you haven't done a lot of these, the cam, manifold. and carb might be a bit much for a weekend. There can be a lot of customizing involved, especially carb and kickdown linkage. If you are pretty quick, no sweat. Changing the cam requires pulling the manifold, anyway. The roller cams are at least 3 times the price of the flat tappet. Hughes cams would require probable changes in the valve train. But using a flat tappet cam requires push rods and lifters. The roller lifters are very different and a lot taller. A flat tappet cam means longer push rods. I was lucky enough to score the push rods off the Dodge motor home I took the manifold off. That motor looks absolutely clean inside and no visible wear on the push rods. You are also going to need a timing chain and gears, because yours is worn. But that is part of the cam job anyway. One word of caution: you might want to go with a holley, edelbrock, or quadrajet carb. The thermoquads can be hard to do. It took me 3 teardowns on mine to get it right. The idle circuit is a tiny passage inside the primary passage and very hard to clean. There is a learning curve on them.
The holleys and edelbrocks are square bores, so you would have to get an adapter, which is cheap, if the manifold you find is a spreadbore. The qj is a spreadbore. Also, you have no way of knowing if the carb you find is ok until it runs. There is a lot of junk in gasoline which settles out in a carb which sits. Most of the time, it's the junk in the gas which causes trouble. The passageways inside the carb are very small and easy to plug. Good filters stop suspended particles, but the refining process leaves in a lot of things like varnishes and shellacs, which don't do much harm until the carb sits for a few months. And this is often what you get with a used carb.
You can get a lot of power without spending much, if you can get good prices from someone on the forum or from a local salvage yard.
For some background, check tech articles from magazines like mopar muscle.
I think it's important to remember that when you customize, it can take more time than you plan.
I agree completely. So pay attention to the above comments. Every time you make a change from the original design, you need to allow for the time it will take to figure out how the new parts are going to work with the old ones. If you've done it before, less time needed. If it's your first time - you won't know until you're finished. Not trying to scare you off - just letting you know what's involved. It's still a lot of fun and a painless learning process and that's part of why some of us old f--ts are still at it! Enjoy!!
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