318 build, my first engine build

[Greenmachine225]

hey guys, so I’m going to start building my first engine and I got my hands on a 318 and 360 for free. The 360 was a 1979 but had a crack so I gave the bottom end away and kept the heads and rest of the top end. The 318 is a 1971 block and it’s all good just needs machining. So I’ve read up and found that kb167 pistons will up my compression and I figured I might as well get some forged rods for it. But for the rest of the engine I ve seen many different opinions and builds. I wanted to see what you guys have experienced and what you would suggest in building a nice street performance 318. I’m putting it in my 71 Duster I bought three years ago as my first car and the /6 of course isn’t what I prefer. Anyway I don’t wanna go on forever talking so I’ll post some pictures with this and leave it at that. By the way I am also on a low budget with this build.
Thanks, Carson

 

[Wyrmrider]

318 rods are forged already just stick some mopar performance rod bolts in them
are you going to rebuild the heads? I suggest k line the guides then multiangle valve job then U hand blend the bowl
better have that crank checked but it might just polish
looks like some rust but it might clean up at .020
dbl check your compression ratio- best to cc your heads or read up what they actually are compared to what is usually printed- lots of threads on this but it makes a big difference
remember that piston takes extra care setting ring gap
you will not have any quench with that combination
I'm going to modify this list for LA but for now see B/RB Standard Cams
keep asking questions

 

[AJ/FormS]

Try not to do this:
Low compression, a big cam, stock TC, and 2.76 gears. It never works out in a streeter.

If it's in the budget, some closed chamber heads will really wake up your teener with those 167s. With 58cc heads, it is possible to make around 10.1 to 10.2 Scr. This will allow a cam with about a 62* ICA, to make a lotta teener punch.
Guess what cam has a 62*ICA, hyup the 268/276/110.
Normally, this cam is a bit on the big side for a teener, cuz normally guys screw it together with the wrong compression ratio. But at 10.1, you're all set.
Well, yur still gonna need; a 4-barrel system, headers and a hi-flo dual exhaust, a TC, and probably gears too,with a suregrip,a transmission,tires, brakes,a torque limiter, a V8K and Tbars,a HD cooling system,a distributor,a tach, a rev-limiter.............
Nice Duster!

The 268 cam is a little hard on gas. The next smaller cam is significantly better. If you get it in a SolidFT, you can keep about the same .050 or so, but you will have to fine-tune the Scr down a bit. This will drop about 7 or 8 degrees of overlap. The less overlap will be a lil less fussy about having headers.
Without the overlap and headers it will make a lil less power, but if the price of gas goes thru the roof in the coming years, it's something to think about. At this power level, it might only be 12hp, no big deal. Leave the spare tire at home and you'll never feel the difference.The smaller cam will make more low rpm torque than the stock 318, but will still want a bit more than the stock 1850 stall,perhaps 2400 and probably at least 3.23s..

Happy HotRodding

 

[CCHHAARRGGER!]

1985 318 California cop car motor with 360 heads and a good MP purple cam 268 ( they no longer make this cam, but comps has something similar) or so made lots of power and was damn fun to drive. I would talk to Gilroy Automotive Machine. He knows a lot about mopars. He has done work for some, including myself , mopar guys down in the south bay. He does engines and heads. Do not take it the guys in Cupertino, I think its Clarks machining never meet people that are so full of themselves.

I bought a 318 with 9 to 1 compression and an edelbrock cam. I decided to try the swirl port 302 heads vs the 360 heads. If I had to do it again I would use 360 heads . This is in a 64 dart with a 4 speed.

Assuming you are an automatic, stick with 9 to 1 or 9 to 5 compression with 360 heads and you will enjoy it

 

[Greenmachine225]

Try not to do this:
Low compression, a big cam, stock TC, and 2.76 gears. It never works out in a streeter.

So I have a 2.94 sure grip I’m gonna put in it and I plan to use a decent size cam but nothing crazy and I’m definitely gonna do what I can to up the compression, thanks man!

 

[Greenmachine225]

1985 318 California cop car motor with 360 heads and a good MP purple cam 268 ( they no longer make this cam, but comps has something similar) or so made lots of power and was damn fun to drive. I would talk to Gilroy Automotive Machine. He knows a lot about mopars. He has done work for some, including myself , mopar guys down in the south bay. He does engines and heads. Do not take it the guys in Cupertino, I think its Clarks machining never meet people that are so full of themselves.

I bought a 318 with 9 to 1 compression and an edelbrock cam. I decided to try the swirl port 302 heads vs the 360 heads. If I had to do it again I would use 360 heads . This is in a 64 dart with a 4 speed.

Assuming you are an automatic, stick with 9 to 1 or 9 to 5 compression with 360 heads and you will enjoy it

I’ll definitely contact them in gilroy, I’ve been looking for a decent machine shop, thank you

 

[Greenmachine225]

318 rods are forged already just stick some mopar performance rod bolts in them
are you going to rebuild the heads? I suggest k line the guides then multiangle valve job then U hand blend the bowl
better have that crank checked but it might just polish
looks like some rust but it might clean up at .020
dbl check your compression ratio- best to cc your heads or read up what they actually are compared to what is usually printed- lots of threads on this but it makes a big difference
remember that piston takes extra care setting ring gap
you will not have any quench with that combination
I'm going to modify this list for LA but for now see B/RB Standard Cams
keep asking questions

 

[Greenmachine225]

Yeah I’m definitely gonna rebuild the heads and I wanted to have some work done but I wasn’t sure what I needed, I’ll have the crank checked for sure, thank you!

 

[j par]

My car also came with a cop 318 motor with 360 heads windage tray. Originally a slant 6 air condition. It had a purple camshaft and was a little screamer at the track. Just drop that camshaft off to be made smaller after making it bigger lol. Actually using the same exact 596 smog heads on my Stroker right now and they work great.
I did this 318/360heads last summer and have a thread about it but definitely the same culprits will probably chime in here. But anyways I cut fifty thousands off the heads. If I did over again I would have probably cut more off and still been able to make the intake manifold fit without any problems. You get the bigger valves but you have to shave the head down to bring your compression back down. On my Stroker motor of course I didn't have to do this it was already heavy on compression.
Also people will have their opinions on the smaller ports maybe creating more of the vacuum but I say bologna! LOL

 

[j par]

Yeah I’m definitely gonna rebuild the heads and I wanted to have some work done but I wasn’t sure what I needed, I’ll have the crank checked for sure, thank you!

If you have to spend a little bit of money it's okay to do it on the heads. People start to argue that by the time your five or six hundred dollars into doing your heads which unfortunately it could get up to about three or four at least you could start to be on your way to having some Edelbrock heads, but I still haven't been able to afford them yet.

 

[krazykuda]

hey guys, so I’m going to start building my first engine and I got my hands on a 318 and 360 for free. The 360 was a 1979 but had a crack so I gave the bottom end away and kept the heads and rest of the top end. The 318 is a 1971 block and it’s all good just needs machining. So I’ve read up and found that kb167 pistons will up my compression and I figured I might as well get some forged rods for it. But for the rest of the engine I ve seen many different opinions and builds. I wanted to see what you guys have experienced and what you would suggest in building a nice street performance 318. I’m putting it in my 71 Duster I bought three years ago as my first car and the /6 of course isn’t what I prefer. Anyway I don’t wanna go on forever talking so I’ll post some pictures with this and leave it at that. By the way I am also on a low budget with this build.
Thanks, Carson

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If you buy 10.5 compression pistons for the 318 and throw on the 360 heads, you will end up around 9.2 compression and benefit from the larger ports and also have 2.02" intake valves installed...

 

[Murray]

I like how krazykuda thinks. Most of your HP is in the heads so it seems reasonable on a street motor to do a modest rebuild on the bottom end and spend a little money on the heads. You will be using hy-test gas. I see those 2.94 freeway gears as a hinderance to more performance. I see you at local shows- good luck.

 

[toolmanmike]

318 rods are forged already just stick some mopar performance rod bolts in them
are you going to rebuild the heads? I suggest k line the guides then multiangle valve job then U hand blend the bowl
better have that crank checked but it might just polish
looks like some rust but it might clean up at .020
dbl check your compression ratio- best to cc your heads or read up what they actually are compared to what is usually printed- lots of threads on this but it makes a big difference
remember that piston takes extra care setting ring gap
you will not have any quench with that combination
I'm going to modify this list for LA but for now see B/RB Standard Cams
keep asking questions

Let's not confuse the issue with big block cams.

 

[rumblefish360]

I like how krazykuda thinks. Most of your HP is in the heads so it seems reasonable on a street motor to do a modest rebuild on the bottom end and spend a little money on the heads. You will be using hy-test gas. I see those 2.94 freeway gears as a hinderance to more performance. I see you at local shows- good luck.

Bingo! This ^^^^

Cam accordingly and you’ll be in good shape.
Work on the heads for best power return on money spent after the short block is done.

 

[toolmanmike]

Study up. This subject has been beat like a red headed stepchild before. Search Results for Query: 318 build | For A Bodies Only Mopar Forum

 

[Wyrmrider]

Not just Big Block Cams- Mopar lobes are Mopar Lobes only the part number changes
Comp has nothing similar to the 268 DC Cam off the shelf Lunati does on the shelf and Howard could grind one, so could Bullet or Crane
well actually the HE274HL has the same real seat duration as the MOPAR The Comp HE 268 is much shorter than the Mopar 268
BVVC

 

[JBurch]

Low budget; famous last words..........not to say it still can't happen.......only do what you GOTTA DO, not every engine build has to be a Pro-Stock

KB 167 pistons are a good choice, by the numbers they will sit about .012 down in the hole, this will help build compression. Have the big ends of the rods checked for proper size, re-size only if needed, I wouldn't change out the bolts, just my opinion, part of low budget. Quick question, what did the bearings look like when you tore it down? What is the date stamp on the back side, it will be month/year, standard (std) or under size? IF, IF, IF, by some chance the the date code of the bearings match up to be originals; some date in 1971; meaning this engine has not been molested in it's lifetime, that is a plus. By the pics the valley is very clean, not a lot of sludge, means this engine was cared for, got regular oil and filter changes, if the bearing don't look beat and down to copper, the crank may only need to be polished and left alone. You will need to have rotating assembly balanced due to piston swap.

Use the 360 heads, have a valve job done, no need to go 2.02 intakes, 1.88, 1.6 valves are plenty, if guides are loose have them knurled, cost less than new guides, has about a 40,000 mile life span, unless you intend to have car longer than it will take you to roll up 40,000 miles, then do guides, cast iron is less expensive. Have heads milled to reduce chamber volume to 60-62 cc's range, again compression building. Just about any dual plane intake will do, even factory cast iron, cam shaft there are dozens to choose from, pick the one that complements how you are gonna drive the car , error to the side of small.

Be prepared for LOT'S of ideas..........

Good luck and have fun.

 

[stumblinhorse]

I am stroking my 318 to 390. Not a lot more money if you already have decent 360 heads...

 

[toolmanmike]

Low budget; famous last words..........not to say it still can't happen.......only do what you GOTTA DO, not every engine build has to be a Pro-Stock

KB 167 pistons are a good choice, by the numbers they will sit about .012 down in the hole, this will help build compression. Have the big ends of the rods checked for proper size, re-size only if needed, I wouldn't change out the bolts, just my opinion, part of low budget. Quick question, what did the bearings look like when you tore it down? What is the date stamp on the back side, it will be month/year, standard (std) or under size? IF, IF, IF, by some chance the the date code of the bearings match up to be originals; some date in 1971; meaning this engine has not been molested in it's lifetime, that is a plus. By the pics the valley is very clean, not a lot of sludge, means this engine was cared for, got regular oil and filter changes, if the bearing don't look beat and down to copper, the crank may only need to be polished and left alone. You will need to have rotating assembly balanced due to piston swap.

Use the 360 heads, have a valve job done, no need to go 2.02 intakes, 1.88, 1.6 valves are plenty, if guides are loose have them knurled, cost less than new guides, has about a 40,000 mile life span, unless you intend to have car longer than it will take you to roll up 40,000 miles, then do guides, cast iron is less expensive. Have heads milled to reduce chamber volume to 60-62 cc's range, again compression building. Just about any dual plane intake will do, even factory cast iron, cam shaft there are dozens to choose from, pick the one that complements how you are gonna drive the car , error to the side of small.

Be prepared for LOT'S of ideas..........

Good luck and have fun.

Great advice!

 

[273]

Build for the gear, with 2.94 gears your not gonna spend much time above 4000 rpm.

A similar built 360 an optimal gear would be in the 4.10-4.56 range and acceptable compromise would be 3.55. A 318 needs about two steps higher (0.5:1) to have similar performance. To me 3.91 should be the least gear for any decent cammed 318 or accept your leaving a lot of power unused.

Thats a dyno of a 360 380hp create engine.
From 5000-6000 rpm it basically making the top power of 400 hp. But at 3800 rpm its down about 100 hp and by 2800 rpm its down another 100 hp making only half.


Less gearing gives you less rpm per mph.
Giving you less hp at any given mph to use to accelerate your car. Better to cam for more under 2000 rpm power even at the expense of 4500 rpm plus power. Especially if your not spending any real time up there.

Basically what Im saying its not worth trading 25-50 hp at the bottom for 25-50 hp at the top.

I probably wouldn't go bigger than comp xe262hl or similar with those gears.

With 360 heads and decent cr should put you at 1 hp per cid around 5000 rpm and 1.15 lbs-ft per cid a 1000-1500 rpm lower.


Could also run deeper 1st and 2nd gear. Will make stop light to stop light action a little more fun.

 

[QuickDart360]

3.91s are fuuuunnnnn!!!