318 build

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7dswinger

7dswinger

MOPAR's rule
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After doing some reading I'm going to start setting aside some $$$ to build an engine for my dart and since I have a 318 block sitting around I thought why not. Only problem is I'm a noob when it comes to engines so I'm hoping to get some help with picking the parts. I'm not looking for a monster but for something pretty fun around town but not hard on the wallet building or running.
Here's what I've specced out so far:
Keith Black Pistons -3.910 bore, 1.741 comp. distance,
http://www.summitracing.com/parts/UEM-1266C-STD/

Lunati Voodoo cam and lifter kit - Duration 262/268 Lift 475/494
http://www.summitracing.com/parts/LUN-60402LK/

Going to try to and find some 302 heads (where should I look?), using stock rocker arms, don't know what springs to run either, could use some help there as well.

Any other ideas on what I'm going to need here or stuff that I should look at?
 
That's a good cam and about as far as i'd go on what will turn out to be a fairly low comp. ratio. When you get your heads you'll have to measure the chambers to see where you really come out. I'm guessing the 8.5to1 range. Lunati lists a recommended spring, but you may get away using a stock Mopar 340 spring. Gearing and torque converter will be a big factor on how this package runs, just make sure you use a dual plane manifold and a carb in the 600-700cfm range.
 
I've got a dual plan Edelbrock RPM that I'm hoping to use otherwise I'll shell out some for an RPM airgap.
I'm planning on a comp ratio somewhere like 9 to 1 to 10 to 1 so I'm guessing taking the chambers on the heads down to 55cc and a thin gasket would help with that goal. The other thing that I've heard that helps is getting pistons to be flat with the deck of the block as they are set fairly far into their holes stock. Do I need specific pistons for this or do I need the block machined for that?
Thanks for the help,
Brian
 
7dswinger said:
The other thing that I've heard that helps is getting pistons to be flat with the deck of the block as they are set fairly far into their holes stock. Do I need specific pistons for this or do I need the block machined for that?
Thanks for the help,
Brian
Click to expand...

A piston like this would get you closer to the deck, but they are more $$$. Might be offset by less machine work and a better fitting intake because of all the decking and milling?

http://www.summitracing.com/parts/UEM-KB167-STD/
 
KB399's will give you more compression withou the expensive machine work.
 
I agree with the others, I'd run a KB167 in that 318. That will give you a better quench and compression ratio with less milling on the heads. Milling the heads that much is going to mean milling the intake, custom pushrods, etc, so the $$$$ adds up quick. Cheaper to get the right pistons.

You'll probably want to have the block square decked, its not uncommon for the decks to be different heights. After that you'll have to check to see where you're at with regard to the piston and deck clearance, zero deck is usually where you want to be, although if you get 302's you may want to leave a little extra, since they're closed chamber and you may end up with a bit too much compression. I had the 318 for my Dart square decked, it was so far out that my pistons ended up .005" proud of the deck (although they had a shorter compression distance to start with like the 167's).

A lunati 60402 is a great cam, although I've yet to fire my 318 I went with a 60403. But I'm also running RHS heads and a few other goodies, so I wanted to make use of them.

I'd seriously consider getting a set of Magnum heads instead of the 302's, they have bigger valves, a 1.6 ratio rocker, and better flow. Plus they're closed chambers like the 302's. You'd need the Magnum rocker set up and oil through push rods, and you'd have to get a Magnum intake as well. But if you're not planning on doing any port work to the 302's, the Magnums will be a better performer for you stock for stock.

Where in Cali are you at?
 
Makes sense, I have no desire to get into a bunch of custom stuff on my first engine build. I have no issue with spending some money on the correct part of something so about 400 for pistons isn't bad. I was also thinking it was going to be around 600 so it's better than what I thought haha. Will I be able to use my stock rods with these as long as their in good shape?
The magnum swap's a good idea. I can probably get some magnum heads from a pick n pull or something and have them re-done. Ordering parts is still a few months away sadly as I've got to get the money for it, just speccing it out so I can the block ready and to the machine shop soon enough but this gives me time to figure everything out.
Any one got any good reading on building small block mopars? I've never done this before so I have no clue about checking tolerances or anything like that.
72bluNblu: I'm located about 30 to 60 minutes out of SF, Los Altos to be exact haha
 
Check out two books, how to rebuild your smll block mopar and how to hot rod your small block mopr. Also once you decide on a piston your going to use google the manufacturers part number and it will turn up alot of places to get them. I did that for my kb191's and found them at cambell enterprises for over $50 cheaper than summit then i called summit and they price matched it plus beat it by $1 lol they even let me get a master engine rebuild kit for my 360 and delete the stock cast pistons the kit came with and put in my 191's just paying the price difference. Those kits save you alot of money and you swap parts on some of them
 
7dswinger said:
Will I be able to use my stock rods with these as long as their in good shape?
Click to expand...

Yup, stock rods will be fine as long as they're in good shape, you should still get them resized and run ARP bolts. If yours aren't ok let me know, I've got a set of stockers I could part with. You should get your rotating assembly balanced though, the pistons will be lighter than the stockers. I had to have a good chunk of weight removed from the crank on my 318 because of how much lighter my new pistons and rods were.

7dswinger said:
The magnum swap's a good idea. I can probably get some magnum heads from a pick n pull or something and have them re-done.
Click to expand...

That's what I'd do on a budget. The magnum heads do tend to crack, but that's true of ALL the induction hardened mopar heads, including the 302's and 308's. So you might have to pull more than one set if you're unlucky. But the pick n pull method will also get you everything else you need, rockers, valve covers, etc. If you have a little more money to spend you can look into buying a set of iron rams in stock form, no worries about cracking and they'll flow better. But, they'll probably cost about twice as much as refurbing a set of stockers.

Biggest thing on a 318 build I think is to get the details right. Get it square decked, set the pistons up close to zero deck, have a torque plate used for honing, and make sure everything gets balanced. The machining will cost more, but you'll end up with a very solid, strong running 318 that will be able to handle more upgrades later if you choose. Do all that, get your compression ratio around 9 or 9.5:1 with magnum heads and that cam and you should easily be over the 300 hp mark.

If you haven't seen this build, check it out. Supposedly a 400 hp 318 build with magnum heads, on a "budget". Way bigger cam and probably a happy dyno, but its not a bad model at all for a 318 build.

http://www.moparmusclemagazine.com/techarticles/mopp_0409_318_engine_build/index.html

7dswinger said:
72bluNblu: I'm located about 30 to 60 minutes out of SF, Los Altos to be exact haha
Click to expand...

Heck I'm not that far away, I'm outside Sacramento. If you need any stock parts let me know, I've got a bunch of stock 318 stuff left over from my builds. I also have a some suspension stuff, V8 torsion bars, 10.8" caliper brackets, 10x2.5" brake stuff, etc. Again, mostly just stock stuff leftover from upgrades, but a lot of it would still be an upgrade over drums, /6 stuff etc. Feel free to shoot me a PM if you're looking for anything, I may have it and I need free up some space here pretty soon.
 
Here are the basics of the 318 I just built with simulated dyno numbers from a fellow FABO member. http://www.forabodiesonly.com/mopar/showthread.php?t=200168

The engine runs nice but haven't got the whole car done yet so been unable to really get the seat of the pants dyno test yet.

After installing the kb167, they were close enough to 0 deck to give me a 9.5 CR with no head or block milling. I reused the stock crank and rods, and the cam came as a kit with the lifters, springs, and timing chain.

There are several car mag articles out there on building a 318. When I did net searches I kept coming up with the same 3 or 4 articles. I used them as a base line and although didn't follow any of them exactly, mirroring them as much as I could with what I already had, I think it turned out pretty good.

Good luck with your parts selection, and look forward to the day parts start coming in....it's like Christmas morning!
 
I was thinking square decking the block but I didn't think about the torque plate thanks.
Crankshaft probably will need to get polished as well but we'll see, definitely balanced though I agree.
What should I be expecting for mpg's as this will go into my daily driver, I'm running the ez efi system right now and that'll go onto this engine (sorry carb folks :D).

That's much appreciated I'll let you know if I run into something that I need.
 
MPG's will depend quite a bit on gearing. But I would expect high teens for sure, especially with the EFI. I've heard of guys getting 20-22 mpg with well built 318's, even with carbs.

My Challenger with poor tuning, extra weight, giant headers and a 600 cfm Carter gets 13 mpg around town with my foot on the floor, and as much as 16-17 mpg on the freeway. I lost a couple MPG's when I swapped the 2.76's for 3.23's too. I'd do better around town if I had less fun, but, that's less fun. :D
 
72bluNblu said:
I'd do better around town if I had less fun, but, that's less fun. :D
Click to expand...

Exactly haha. Well that's my reason for planning this build as I'm getting around 10 to 12 with my current 318 highway and I'm pretty sure I don't have 4.10 gears or something. We've looked over everything and done what we can to help but to no real avail so I think it's time to stop trying to backwards engineer this engine and start from scratch on something we know.
 
7dswinger said:
Exactly haha. Well that's my reason for planning this build as I'm getting around 10 to 12 with my current 318 highway and I'm pretty sure I don't have 4.10 gears or something. We've looked over everything and done what we can to help but to no real avail so I think it's time to stop trying to backwards engineer this engine and start from scratch on something we know.
Click to expand...
You're still getting 10-12 mpg on the highway ?? WTF , you should get much better than that . Is that with the EFI , if yes maybe it needs more time to get in "tune " . What converter you have ?
 
jerry6 said:
You're still getting 10-12 mpg on the highway ?? WTF , you should get much better than that . Is that with the EFI , if yes maybe it needs more time to get in "tune " . What converter you have ?
Click to expand...

Oh it's better from the 5 I was getting with the carb haha.
Yes the 10 to 12 mpg highway is with the EFI. It's been "tuning" itself from oh I'd say a month now since I had a shop do a bunch of work on it, replaced timing chain with double roller as the old one was loose, tuned it and some other things. Compressions perfect, leak down tested and all's good. Nothing's wrong with it (so far as anyone can tell).
I have no clue what the converter is, is there a way to tell without dropping the tranny out?
 
Not bad thanks, are Badger pistons any good?
I'm going to go up to my parents house this weekend to finish taking the block apart and see what I'm going to be dealing with.
 
The Badgwrs are a fine piston but are stock replacements. Low compression ratio.
 
^^ ah ok. I want to zero deck the block so that would be a problem I'm guessing?
So I did a test today and if my numbers are correct I'm getting around 11mpg highway...WTF???? I don't get it haha
 
7dswinger said:
^^ ah ok. I want to zero deck the block so that would be a problem I'm guessing?
So I did a test today and if my numbers are correct I'm getting around 11mpg highway...WTF???? I don't get it haha
Click to expand...

Yeah that's pretty awful, especially for EFI. Somethings not right there, I mean, I do better than that around town with the secondaries open...

What kind of vacuum numbers are you pulling? And what's the timing set at? Plugs black as night?
 
7dswinger, Keep us posted on your build, I'm interested to see your finished product. i'm in your neighborhood as well (San Leandro) and building a 318 as well. I went with stock bottom end due to budget restraints with upgrades to the Cam, heads & exhaust. I was able to find a set of 302's in Santa Rosa last month for a very reasonable price & having them massaged & 340 size valves installed. I went with the Comp xe268 with the recommended springs & double roller timing set. 600 Holley vac & performer intake. I don't have headers yet & cant really afford the KB167's, but for the intended use, which is just cruising & showing off I imagine I'll be fairly pleased for now. Just swapped the stock converter for a Hughes w/ 2000 stall & looking to upgrade my 7.25 rear but looking for the right deal on the gears or an 8.25 to cross my path. Wish you lots of luck with your build & hope to run across you at a local event, Maybe good guys in Sept.
 
Sounds good I will, hopefully things won't be too far off in the future :D
^basically sounds like what I'm doing I'll be interested to see how it works out for you. I hear you about the 7.25, I feel like I'm going to blow mine up if I do anything with a new engine. For sure let me know, I've been looking to go to a few but haven't had the time sadly.
72blunblu: I honestly don't know what vacuum it's pulling or what the timing is set at, which is semi embarising for me to say :banghead: . I had a shop set the timing for me as I couldn't get it. It's pretty close and if I remember right I think it's running around 25 degrees right now but then again I have no clue, I'll have to go check with my light and put some timing tape on there as the old one fell off.....
I don't have a vacuum gauge either, maybe I'll pick one up.
 
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