Suggestions for a 318 build

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Fishthatkills

Fishthatkills

Fish that kills
Joined
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Austin Texas
Howdy all,
I have just aqquired a '73 318 and a A904 tranny for FREE! I want to build a somewhat mild to medium street motor. Nothing crazy mind you but enough to kick some import butt and some modern day rides. Looking for around 300 horses with non exotic parts. This build will be going into my '67 barracuda which now has a 273/A904/7 1/4. the car is bone stock and I like it that way. Will want to upgrade the rear end to a 8 1/4 or 8 3/4 if I can find one at a good price

What modifications should I consider on the 318. Overbore? pistons, rotating assembly, heads, intake etc? I plan on taking my time with this to do it right! So the budget can be spread over time.

Anyone know a good machine shop in the central Texas area?

Thanks,
John D. Beckerley
Austin, Texas
 
IMO, honestly, seriously, stop looking at 300 HP and look for 400 to start with. After all, you said;
but enough to kick some import butt and some modern day rides.
Click to expand...

Are you willing to do;

A high stall converter and gear ratio?
Add an overdrive for cruising if need be? As in the rear gear to high for your taste.
You do realize modern day rides have every advantage over you except cubic inchs and they have to pass emmisions. Many of these modern day car, performance sedans, will run mid 13's no questions asked or breaking a sweat doing so.

(OH, by the way... nice sig. I agree! Anybody can help pay for what they don't like about my car as well. Break your bank I will. Ha ha ha)
 
Not looking to run an overdrive tranny. 400 hp is it a reality in a 318 build? Are we talking stroker? Lots of machining? It's my first engine build so I am not hip to what can be done to a small block. I have to stick to what I have or risk divorce Ha! Ha! It has to be somewhat reliable too. Maybe the most exotic part would be eddy heads and a tunnel ram! I don't really know!
 
400 out of a 318 is doable and easy with a med. size cam. There have been a few mag write ups on the matter.

No exotic parts needed. No stoker cranks. Nothing over the top or expensive to search for. The amount of machining is mostly up to the condition of the block and what it needs. Otherwise, a standard type of work should be done. IF it needs and over bore, then overbore it. If the cranks needs to be machined, machine it. Nothing fancy going on here.

I would suggest a set of KB flat top zero deck pistons for a good compresion ratio.
I think there the KB 167's. They need not be at zero deck exactly, but a good bump in compresion is what is needed for a good performance start.
Also, if your con rods are bent and need rebuilding, new after market rods work out cheaper and lighter.

Would a set of 4.10's be to much gear? OR a cruise on the Hwy. @ 60 and 3300 rpm to much?
I can and have lived with this for years. Since it was not a daily driver and such, it was very tolorable.

My pervious hot rod (73 4spd Cuda/360) ran such gear and low 12's, pump gas, went everywhere anytime, and it wasn't a mother to maintain. Driven 3 - 5 times a week.
 
OK, I'll keep it comeing after you answer the questions.

Would a set of 4.10's be to much gear? OR a cruise on the Hwy. @ 60 and 3300 rpm to much?
I can and have lived with this for years. Since it was not a daily driver and such, it was very tolorable.
Click to expand...

We all could sit here spending your cyber money all night long with combo after combo, but we'll wait for the answers and, in general, what your willing to put up with on the car.

We are still in the dark some. Wanna help, but can't really.
 
Sorry, yea 3.55's 4.10's I can live with. Don't really know how much highway driving I'll be doing. This is my fun car. Sort of my cruise the B L V D car. I can always go to a higher ratio if I can't take the whine. 3000 stall converter and shift kit is in the future as well. Not so much that I will want to race everyone I see. Just don't want a Mopar to be smoked by a Honda if you know what I mean. I guess what you mean is how mean I want it. A good cam not too choppy and able to keep my power stuff brakes mostly! As far as drivability, well the wife may want to take it for a spin once in a while. Not a race car but not a grandma either.
 
Just to give you a combo idea I have a 318 that I built that was in my cuda. I chassis dynoed the car at 301hp to the rear wheels. Should be close to 400 crank hp. I don't want to confuse you with the bottom end because it's a mutt. I posted it but ignore it. Just plan on between 9.0-9.5 - 1 compression and a stock displacement 318. with the cam, heads, and an air gap intake instead of a six pack like I used.

348cid
1970 318 block bored .025 over
.060 over 283 pistons with custom dishes and crank clearanced
3.58 stroke small journal cast crank from mopar rods cut to 2.100 journal
chevy eagle rods, 6.000 long, large journal

Rebuilt stock cast magnum heads with 2.02 intake 1.625 exhaust valves
Guide cut down for retainer clearance. Bowl hogged NO HAND WORK!!
I had Hughes engines redrill the intake pattern to use the older intake.

Lunati off the shelf cam 225 @ .050 duration .480 lift intake 225 @ .050 duration .480 lift exhaust 108 deg LSA Installed straight up. The magnums use a 1.6 rocker from the factory. It increases the lift to .512

Stock rocker gear and mopar perfromance head swap pushrods.

Six pack intake and carbs

TTI headers and TTI 2.5" exhaust

Stock windage tray

This engine ran beautifully!!! It has a little idol lope, ok vaccume (you might have to use a vaccume accumulator can for power brakes), and did the boogey very well with 4.10s infact my father liked it soo much when I decided to put he hemi in my cuda he wanted the entire setup for his 67 coronet convertible.​

 
hemijoe thats an out of the box combo! My kinda motor,but I will admit that there are easier and cheaper ways to make that kind of power. In fact the same 318 without the extra stroke and a stock bottom end did make 400 h.p in a magazine build. Mag heads,stock 318,kb 167 piston and an air gap got it over 400 h.p. A similar thing was done with 302 heads that were ported and it had a slight edge over the mag version. BUT ,the mag version had stock heads and the wrong cam IMHO,lol.
 
needsaresto said:
hemijoe thats an out of the box combo! My kinda motor,but I will admit that there are easier and cheaper ways to make that kind of power. In fact the same 318 without the extra stroke and a stock bottom end did make 400 h.p in a magazine build. Mag heads,stock 318,kb 167 piston and an air gap got it over 400 h.p. A similar thing was done with 302 heads that were ported and it had a slight edge over the mag version. BUT ,the mag version had stock heads and the wrong cam IMHO,lol.
Click to expand...

Yea I know, that's why I said to not pay attention to the bottom end. I wanted to be different. If you used a stock displacement 318 with the same heads, cam, air gap intake, and a good set of headers would make very close to the same HP. Almost the same thing as in the magazines.:read2:
 
Interesting combo there joe.

Fish, I'll stick with a 3.55 rear axle combo thoght pattern and leav the 4.10's for some other day. Stick with a tire no larger than 245/60/14 (25.6 inchs, 26 inch acceptable)

A Comp Cam XE274 (1800 - 6000 rpm) and a 2200 stall converter inside a 9 - 9,5-1 ratio engine should do ya very well. Your biggest problem is air flow, AKA head flow.
This is the toss up between 360 heads and ported 318 heads w/360 valves.
Use a dual plane intake and a 600 - 650 cfm carb. (Weiand Action plus or a RPM are very good for this set up. A on the cheap would be ethier a Edel. Performer or OE Iron intake. They'll still work well.)
TTI makes the best headers, though expensive, there worth the price.
2-1/2 max size exhaust pipe. (Into a X would be great.)
 
If you want to convert your 318 to a magnum head mill I've got rebuilt Magnum heads with the proper Mopar Performance springs, retainers and keepers, valves and seats ground, cleaned and inspected. I also have a Comp cam #20-222-3 262/270 duration.462/.470 lift or .492/.501 with the 1.6:1 Magnum rockers. I have the proper AMC lifters and Mopar pushrods for the Magnum head conversion.I also have the #P4876759 MP headbolt package I have a #7577 Edelbrock RPM Air Gap intake
and a pair of Mopar performance black finned valve covers for Magnum.
I'll have to dig up the reciepts and give you a price if you're interested. I would like to sell the whole thing but would intertain piecing it out. Pm me. toolmanmike PS everything is new except for the heads.
 
Exactly ToolManMike. I was about to suggest the article on the whole build they did. No exotic parts nothing outlandishly expensive its all over the counter easy to acquire and relativity cheap parts. Read through all of that and it will give you more then enough to get 400Hp out of a 318 without any stroking and hardly any work.


Jeff
 
Thanks for all the thoughts. I did read the the articles and they are pretty good. I really like the Mopar Muscle Mag write up. Thats what I am talking about. Like I said this will be a no hurry build. I want good power and good driving manners. I did read the latest post about 318 vs 360. I will stick with my new edition 318. It was free and that's always a good thing. I will keep you all posted as I go along. And will be asking many more questions as I progress.

Thanks a bunch!
John B.
 
Badart said:
These little 318 love the magnums. That's what I did.
Click to expand...

The port size is ideal for a 318 with a bigger than stock cam.They can handle up to .524 or so lift just with a spring change. Excellent ex port,good intake. Some guys try to balance the flow a bit better by using 1.5 rockers on the ex,if they are using a split pattern cam. I would use a single pattern as the mags just dont need more help on the ex,lol.Also have to keep in mind when selecting a cam that your going to get "free" lift and duration because of the 1.6 rockers. I think a .480 will work great..like maybe one of comps grinds..

The air gap intake is perfect for them.They have no heat X over anyways...
 
I've been thinking about the next step my 318 (in my sig) will go to and the RHS replacement Magnums seem like a promising upgrade over my 302s. I know with porting and switching to larger valves I could make 302s work great but I don't think all that work would be worth it when low-cost new high-flow iron heads can be had. Then I might reuse the same Voodoo cam with 1.6:1 rockers and zero-deck pistons for 9.5-10:1 comp, along with maybe an Edelbrock RPM intake and some nice headers, of course. In your case you would be able to get a bigger cam in the first place (I need to save $$$), such as the Voodoo 262/268 or any other good modern fast-ramp cam in that range. With the combo I mentioned I think you could probably push 350 HP with still decent bottom end. Bigger cams would make more power but the 318 is small and more "sensitive" to big duration and overlap than say a 360.

EDIT: If what needsaresto says is true then you might actually get better results with a different type of cam...
 
Car Carft as an interesting 318 build this month. Actuallly, they stroke it with w 4 inch arm and added the RHS heads. While the head line is 500 HP for $5000, they actually must have did the write up in a rush since they never mention a cam they used or showed a dyno slip.
 
There are a few things to keep in mind that no one seems to mention when they talk abouth these " cheap and easy to build "400 hp 318s. These guys are sharp tuners with years of experience and have a dyno , a luxury most of us don't have. Lacking super tuning skills and dyno time, subtract 20 hp. Add accessories, subtract another 20 hp. Breathe in hot underhood air, subtract another 10-20 hp. Something else to consider is that Westech ( where those engines mentioned were dynoed) is rumored to have a "happy" dyno. Whether that is true or not, don't expect in-car performance of your own engine to match those in magazine articles. Ever notice when a magazine puts a dynoed engine in a car and actually takes it to the track, the results are often disappointing. Then they say "Gee it made almost 600 hp on the dyno but only runs 12s". Not trying to be a bummer, i'm just saying "results might not be typical".
 
With the availability of stroker kits available and affordable, I would start with the 390 cu. in. You will hit your HP mark much easier and will be a whole lot more streetable .
 
forphorty said:
There are a few things to keep in mind that no one seems to mention when they talk abouth these " cheap and easy to build "400 hp 318s. These guys are sharp tuners with years of experience and have a dyno , a luxury most of us don't have. Lacking super tuning skills and dyno time, subtract 20 hp. Add accessories, subtract another 20 hp. Breathe in hot underhood air, subtract another 10-20 hp. Something else to consider is that Westech ( where those engines mentioned were dynoed) is rumored to have a "happy" dyno. Whether that is true or not, don't expect in-car performance of your own engine to match those in magazine articles. Ever notice when a magazine puts a dynoed engine in a car and actually takes it to the track, the results are often disappointing. Then they say "Gee it made almost 600 hp on the dyno but only runs 12s". Not trying to be a bummer, i'm just saying "results might not be typical".
Click to expand...

Very true but even if you could get 350 hp out of one with a basic build it would be good. Mike
 
Fishthatkills said:
Howdy all,
I have just aqquired a '73 318 and a A904 tranny for FREE! I want to build a somewhat mild to medium street motor. Nothing crazy mind you but enough to kick some import butt and some modern day rides. Looking for around 300 horses with non exotic parts. This build will be going into my '67 barracuda which now has a 273/A904/7 1/4. the car is bone stock and I like it that way. Will want to upgrade the rear end to a 8 1/4 or 8 3/4 if I can find one at a good price

What modifications should I consider on the 318. Overbore? pistons, rotating assembly, heads, intake etc? I plan on taking my time with this to do it right! So the budget can be spread over time.

Anyone know a good machine shop in the central Texas area?

Thanks,
John D. Beckerley
Austin, Texas
Click to expand...


HEY FISH,
HERE IS SOME EXTRA INFO THAT MIGHT HELP. 1970 318(.030) , TRW PISTONS,STOCK CRANK( 10/10 ) , 360 HEADS (587 CASTINGS ) ,BLUE RACER CAM ( .446/.464 292 DURATION ) PERFORMER MANIFOLD,EDELBROCK CARB(650),HEADERS,HEADS SHAVED .010,BLOCK DECKED,8.25 REAR/3.55, 904 W/SHIFT KIT,STOCK CONVERTER. ENGINE DYNOED @ 336HP/4700RPM. HAD ENGINE IN A 1969 CUDA FB AND RAN 14.20S CONSISTANT WITH RADIAL T/A TIRES. I GUESS IT DEPENDS HOW FAST YOUR WALLET CAN GO! 400HP OR NOT, THESE MOPARS ARE FUN! GOOD LUCK WITH YOUR PROJECT.
 
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