318 complete combo suggestions...

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Danilo

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I have a numbers matching 1969 Barracuda with a 318, auto. I have done a disc brake swap and I have an 8 1/4 rear end.
I would like to wake it up nicely. It will never, ever be raced, tracked or autocrossed or anything like that. It will see some longer (6-8 hour) highway trips to car shows but will mostly be driven around town. I would like to install a sure grip post in the back. I will be running a 15" tire.
I am wondering what suggestions may be given for rear end ratio, transmission mods (converter and shift kit), suggested cam, heads, intake and carb - as well as anything else you may offer.
Looking for a fun car to enjoy and feel some power but nothing crazy.
Thanks for reading and for the (anticipated) suggestions!
 
  • 6-8 hr trips, I'd run a 2.94 gear ratio with a 26-27 inch tire.
  • Nice flowing dual exhaust. Manifolds work fine if you don't want headers
  • Keep the cam small. Something around a .427-.450 lift, and duration around 210-216 @ 050
  • Heads are the name of the game for gas mileage and snap. Have a nice valve job done, and if your motor is year correct, hardened seats or buy heads that have hardened seats and do them up. Really don't need to port, but cleaning up casting burrs and barely opening up the ring under the seat in the bowl area will pay dividends along with removing the valve cover bolt lump in the intake port.
  • I'd run a Weiand Action plus intake and a 600 cfm carb of your favorite flavor. Even a Holley 3310 would work great.
  • I'd consider a good aftermarket converter.
 
Use a cam with 260° - 275° duration and maybe throw in some Rhoades lifters for extra low end grunt and vacuum along with more MPG... Shoot for a little bigger than a stock 340 cam... Crane makes a good economy and power cam...


Install larger valves in the stock 318 heads and maybe some porting...

OR if you want to run 340/360 heads, have 2.02" intake valves installed, but the larger port heads also have larger combustion chambers.. If you want to get the most from them, you should install 10.5 compression 318 pistons and with the larger combustion chambers in the 340/360 heads you should end up around 9.2 compression which will run good on pump gas... Stock 318 pistons with 340/360 heads will get you around 7.5 compression, but you will still get benefit from the larger easier breathing ports... You may also consider porting the 340/360 heads a little...

Run a dual plane intake, like the wiand stealth intake:

CHRYSLER 5.9L/360 Mopar small block LA Weiand Stealth Intake Manifolds

Then top it off with a Holley 80457 600 vacuum secondary carb and 5/16" thick split carb gasket:

Here's the Holley 80457 carb, it's calibrated for a late 60's engine and runs pretty good... I've run them for decades on daily drivers and had great performance and economy with them...

Holley 4160 Aluminum Street Carburetor


I like this gasket as it keeps the plenum split intake all the way to the carb which makes the signal nice and strong...

https://www.manciniracing.com/hein4sqboe.html



Also upgrade to a good double roller timing chain, I've run this Edelbrock true roller double roller for years and they hold up well and will easily go 150,000 + miles on a street driven car.... This one is one step above the stock 340 double roller timing chain...

https://www.manciniracing.com/edelbrock4.html
 
Warmed over 5.2 Magnum backed by a GM 2004R and 3.55 gears. That way, you don't cut the car up putting a nice over drive in it and you keep the original drive train.
 
Danilo
has this motor been rebuilt? any idea what psitons are in it
in other words is it a high compression or low compression 318
post up your cranking compression to give AJFormS a hint
you can also PM him about that 340 cam in a 318 and tall gears
IT SUCKS
are you trying to keep this build matching numbers stock looking?
What RRR just said but
I'd do a 93-95 360 magnum with a hyd non electronic 518- 46RH
back to 318 with stock compression
your heads ok or do they need seats and guides?
I'd PM PHR about other heads, or IMM
Cam- tough call till we get your compression but if stock 318 bottom end a Lunati 250 Voodoo or 256 Howards (with 15 in the notes column of the catalog) or best a Mike Jones 256 custom with Mike picking the exhaust depending on stock or headers- with the shelf cams you don't get a choice
what gears now?
 
Remember, you will have to cut the car some to put any of the Mopar over drive transmissions in it. The 200 is small and compact and only requires fabbing a cross member and another drive shaft.
 
Ive woken a number of 318s up with nothing more than stock 340/360 parts.
360 heads w/ port match (may need milling depending yr for compression ratio), 340 manifolds, AVS / edelbrock carb, 340 cam works wonderfully in this combo. Mopar perf ignition w/ orange box is tried and true.
Nothing fancy or overly hard to come by and all can be made to look bone stock to the casual/ untrained eye which may be important, idk.
3:55 gear with most passenger car 15" tire sizing is about as middle perfect as you can get for what you are discribing, if one can be had in the 8 1/4 diff.
 
You have the magic original 1969 318 factory 230 horse power 9.2:1 compression engine.

Drop an LD4B aluminum intake and an Edelbrock 600 cfm carb with 2.94 rear gears and you are good to go.

That is if your engine is low mileage and still holding compression, and does not need a rebuild . . .
 
Basic recipe starters for 318 CID Street cruiser engines.

Carb 600 - 650 cfm carb or a small primary TQ W/electric choke.
Intake - Dual plane intake;
Factory iron 4bbl., Edelbrock Performer or Weiand Action Plus or Stealth.
Dual exhaust, with or without headers @ 2-1/2 inches.
Add an X or H pipe
Cylinder heads, leave stock unless they need work. If so, add larger intake valve @ 1.88 with race prepped valve job. (Added bonus for opening up the heads intake port to match intake manifold)
Camshaft, depends on rear gear and tire size as well as the weight of the car. Tell us that.
What are your rear gears & tire size?
 
Use a cam with 260° - 275° duration and maybe throw in some Rhoades lifters for extra low end grunt and vacuum along with more MPG... Shoot for a little bigger than a stock 340 cam... Crane makes a good economy and power cam...


Install larger valves in the stock 318 heads and maybe some porting...

OR if you want to run 340/360 heads, have 2.02" intake valves installed, but the larger port heads also have larger combustion chambers.. If you want to get the most from them, you should install 10.5 compression 318 pistons and with the larger combustion chambers in the 340/360 heads you should end up around 9.2 compression which will run good on pump gas... Stock 318 pistons with 340/360 heads will get you around 7.5 compression, but you will still get benefit from the larger easier breathing ports... You may also consider porting the 340/360 heads a little...

Run a dual plane intake, like the wiand stealth intake:

CHRYSLER 5.9L/360 Mopar small block LA Weiand Stealth Intake Manifolds

Then top it off with a Holley 80457 600 vacuum secondary carb and 5/16" thick split carb gasket:

Here's the Holley 80457 carb, it's calibrated for a late 60's engine and runs pretty good... I've run them for decades on daily drivers and had great performance and economy with them...

Holley 4160 Aluminum Street Carburetor


I like this gasket as it keeps the plenum split intake all the way to the carb which makes the signal nice and strong...

Edelbrock Heat Insulator Gasket



Also upgrade to a good double roller timing chain, I've run this Edelbrock true roller double roller for years and they hold up well and will easily go 150,000 + miles on a street driven car.... This one is one step above the stock 340 double roller timing chain...

https://www.manciniracing.com/edelbrock4.html

Thanks! Would you also recommend the 2.94 gear? or something a little taller?
 
Danilo
has this motor been rebuilt? any idea what psitons are in it
in other words is it a high compression or low compression 318
post up your cranking compression to give AJFormS a hint
you can also PM him about that 340 cam in a 318 and tall gears
IT SUCKS
are you trying to keep this build matching numbers stock looking?
What RRR just said but
I'd do a 93-95 360 magnum with a hyd non electronic 518- 46RH
back to 318 with stock compression
your heads ok or do they need seats and guides?
I'd PM PHR about other heads, or IMM
Cam- tough call till we get your compression but if stock 318 bottom end a Lunati 250 Voodoo or 256 Howards (with 15 in the notes column of the catalog) or best a Mike Jones 256 custom with Mike picking the exhaust depending on stock or headers- with the shelf cams you don't get a choice
what gears now?

It has never been rebuilt - so stock pistons
I could run a compression test, but I plan to completely rebuild it so changing the pistons won't be an issue.
I am wanting to keep it both numbers matching and stock looking, but don't mind changing the heads and upgrading ignition or other items if it makes good sense.
 
Basic recipe starters for 318 CID Street cruiser engines.

Carb 600 - 650 cfm carb or a small primary TQ W/electric choke.
Intake - Dual plane intake;
Factory iron 4bbl., Edelbrock Performer or Weiand Action Plus or Stealth.
Dual exhaust, with or without headers @ 2-1/2 inches.
Add an X or H pipe
Cylinder heads, leave stock unless they need work. If so, add larger intake valve @ 1.88 with race prepped valve job. (Added bonus for opening up the heads intake port to match intake manifold)
Camshaft, depends on rear gear and tire size as well as the weight of the car. Tell us that.
What are your rear gears & tire size?

Thank you!

I don't know the rear gear, but I will swap out for a sure grip, so It is all open for discussion.
I am hoping to build a solid plan from the back to the front so it all works together. The only thing locked in is that I want to keep using my 15" rims on the car.
 
If you really take 6-8 trips highway trips think about what rpm you want to live with
before picking rear/tire size/trans combo, that adds up $$$ . If you are going to have to buy an intake might as well get an aluminum saves a lot off weight. Small cam 210-215 @ .050 read up on all the flat tappet cam/lifter failures and choose carefully, break in procedure
and oil critical. Clean up the heads,better springs, Mr. Gasket .028 head gaskets.
All other suggestions above make sense IMO.
 
Thank you!

I don't know the rear gear, but I will swap out for a sure grip, so It is all open for discussion.
I am hoping to build a solid plan from the back to the front so it all works together. The only thing locked in is that I want to keep using my 15" rims on the car.
Talking about rear gears. My Swinger had a 2.76 (if I remember correctly) I went to a 3.23 and switched to 255/60-15's. I wish I could have found a 3.55 or 3.73. That switch to 3.23 just didn't make that much of a difference with the taller tires.
 
If you really take 6-8 trips highway trips think about what rpm you want to live with
before picking rear/tire size/trans combo, that adds up $$$ . If you are going to have to buy an intake might as well get an aluminum saves a lot off weight. Small cam 210-215 @ .050 read up on all the flat tappet cam/lifter failures and choose carefully, break in procedure
and oil critical. Clean up the heads,better springs, Mr. Gasket .028 head gaskets.
All other suggestions above make sense IMO.

He won't have to worry about lobe failures with a Magnum. ;)
 
If you really take 6-8 trips highway trips think about what rpm you want to live with
before picking rear/tire size/trans combo, that adds up $$$ . If you are going to have to buy an intake might as well get an aluminum saves a lot off weight. Small cam 210-215 @ .050 read up on all the flat tappet cam/lifter failures and choose carefully, break in procedure
and oil critical. Clean up the heads,better springs, Mr. Gasket .028 head gaskets.
All other suggestions above make sense IMO.
Thanks - makes sense. I really appreciate everyone's input - more help than I expected and it's only been 12 hours!
I have watched people load up on horsepower and have a car they don't enjoy driving or can't take on the highway - or even worse, one that runs like a dog because they didn't do anything to the rear end or tranny. I just want it to all work together as a unit to get the most out of it.
 
If you going to race, track or autocross it why change anything . If you just want to cruise at 60-75 mph you've got the right combo right there . Overdrive maybe , just enjoy .
 
If you going to race, track or autocross it why change anything . If you just want to cruise at 60-75 mph you've got the right combo right there . Overdrive maybe , just enjoy .
"It will never, ever be raced, tracked or autocrossed or anything like that. " from the original post.
 
318willrun basically nailed it. Hwy. gears of 2.94 or lower and a minor cam change at best and of modest size.

Hwy. driving here is limited and I can live with 4.30’s on a 26 inch tire. Not so else where in this country and even more so in the middle where there is a vast distance to be covered to the next town.

The only other option is a overdrive. Then there is minor math involved to get to the final drive ratio for the long cruise.

4.30 (gear) X .69 (O.D. Ratio) = 2.967 final drive ratio.
2.96 by tire diameter by cruise speed equals XXXX RPM.
(Minus converter slip.)
Get to a on line calculator for this.
 
Ive woken a number of 318s up with nothing more than stock 340/360 parts.
360 heads w/ port match (may need milling depending yr for compression ratio), 340 manifolds, AVS / edelbrock carb, 340 cam works wonderfully in this combo. Mopar perf ignition w/ orange box is tried and true.
Nothing fancy or overly hard to come by and all can be made to look bone stock to the casual/ untrained eye which may be important, idk.
3:55 gear with most passenger car 15" tire sizing is about as middle perfect as you can get for what you are discribing, if one can be had in the 8 1/4 diff.
3.55 in an 8.25?
It does,
We did,
It is...
cruises easily at 70 MPH all day long..
 
Okay, I read the last post, I was hoping you were talking about a near stock rebuild of your original block. With your goals in mind, you’re one step past a stock rebuild. All the suggestions here are really good, but here’s how I would do it. If the bores are good, reuse your stock pistons, basic rehone and re ring, reverse the pistons on the rods, get deck milled to zero. If you need to bore it, sealed power cast flat tops with four valve reliefs, install with notch to rear of block, get the deck milled to zero. It will make a little extra noise but also make extra power , i.e. piston slap. Use your stock heads, have them milled to 60cc chamber volume. Use Fel-Pro Permatorque SD gaskets. This will give you between 9.5-10:1 compression, so plan on premium pump gas. Add hardened exhaust valve seats and 1.88/1.60 valves with some extra chamber cuts during the mandatory three angle valve job. Add in some mild home porting ala’ 318willrun (bowl blending and intake gasket match). Use a Crower 3198 cam & spring kit, an edelbrock basic performer intake (available everywhere used for cheap, and it works!) with an edelbrock AVS2 650. Run a set of Dougs headers with a minimum of 2-1/2 inch dual exhausts with an x pipe. Install a complete FBO Mopar ignition kit. Add in 2.94 gears with a 27-28 inch rear tire. If you want the extra around town to interstate “romp and merge” power, run an a999 lockup torqueflite (2.74 & 1.55 ratios) with a custom converter from PTC or Ultimate. I only recommend this combination because I have a similar setup with 10:1 and a sealed power CS1143r cam (222/232 @ .050, .443/.450 lift, 112 LSA) with headers and 1.78/1.50 valves on a three angle cut. Blows stock size (215/70-14) tires off at will with 2.76 gears, 904 and factory replacement type high stall converter. It will do everything you want it to, have power you can feel just off of idle, and will surprise you with how strong a 318 can run when you do decide to air it out.
 
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