318 LA Rebuild Advice

-
K

Koadhen

Member
Joined
Jul 29, 2023
Messages
12
Reaction score
2
Location
California
I am in the process of rebuilding a 318 LA from a 1982 Dodge W150 4x4. All appears to be completely stock except for the cam, intake and carb. This will be my first time ever going this deep into an old block, so I am asking this community for any pointers/advice/thumbs up on my part selection. The truck will be a daily driver with highway usage, light duty and light off-road travel.

In addition, my father replaced the camshaft some 5-6 years ago with a Sealed Power CS-645 Duration@ .050 (Int/Exh): 181/192 ;Gross Valve Lift (Int/Exh): .351/.400 ;LSA/ICL 109/110 - stock replacement that is no longer available. I would like to wake up the engine a bit with a Lunati High Efficiency or the factory performance that is a version of the 340 c.i.

- Keep in mind this a California vehicle so I will have to perform bi-annual emission tests - air pump, egr valve, vapor canisters.
Wheel + tire size = 30" tall
Rear diff. = 9.25" with 3.21 sure-grip
Transmission = A-727 with stock converter

- All hydraulic flat tappet -
#10201002 LUN - Advertised Duration (Int/Exh): 298/308 ;Duration @ .050 (Int/Exh): 232/242 ;Gross Valve Lift (Int/Exh): .462/.473 ;LSA/ICL: 112/112 ;Valve Lash (Int/Exh): Hyd/Hyd ;RPM Range: 2500-6500

#10200206 LUN - Advertised Duration (Int/Exh): 268/268 ;Duration @ .050 (Int/Exh): 218/218 ;Gross Valve Lift (Int/Exh): .457/.457 ;LSA/ICL: 110 ;Valve Lash (Int/Exh): Hyd/Hyd ;RPM Range: 1500-5300

# 10200260 LUN - Advertised Duration (Int/Exh): 253/265 ;Duration @ .050 (Int/Exh): 204/216 ;Gross Valve Lift (Int/Exh): .427/.454 ;LSA/ICL: 112/107 ;Valve Lash (Int/Exh): Hyd/Hyd ;RPM Range: 1500-4500


- Cylinder heads are #4027163 and I would like to do some port and polishing to remove the cast flashing.
- NEW intake manifold - Edelbrock 3776
- NEW Holley 4175 Carburetor 0-80555c
- Looking at Federal Mogul 205717M-000 kit (Assuming I have the standard 3.910 bore, will get a dial bore gauge)
- Maybe new valve springs?
- Looking to re-use factory rockers
- NEW Milodon Brass Freeze plug kit - 34040

My biggest concern is the camshaft. I don't care so much for HP gains and all, I just want the engine to flow a lot better. So wondering whether or not a small upgrade will doom me in emission testing...as far as I know the Tech just sticks the sniffer in your hole (much like just existing in this sate) at idle and then at a sustained RPM level.

IMG_2584.jpeg


IMG_2587.jpeg


IMG_2588.jpeg


IMG_2591.jpeg


IMG_2592.jpeg


IMG_2595.jpeg


IMG_2596.jpeg


IMG_2622.jpeg


IMG_2623.jpeg


IMG_2624.jpeg
 
Last edited:
i'm unclear on the intake and carb-- is that what you currently have or what you are planning on buying? if you currently have them, great. those are excellent for what you want to do.

i see no problem with doing some work on the heads. while it's all apart, and if it's within your budget i'd have a machine shop go thru and check them out and touch up the faces/seats, and drop new seals in. upgrade the springs to match your cam at the same time.

i would probably go with the middle cam, however none of those should get you into any trouble, they're not that wild. you can send yours out and have it reground and have the lifters reground at the same time-- oregon cams is a great place for that, and might even give a recommendation on a specific grind.

be sure to do a new timing set while you're threre.

the gears with those tall tires are gonna be kinda ho-hum, so if you can, maybe get on the hunt for some 3.55's at least. a slightly higher stall converter and shift kit would be a great upgrade as well.

other than that, it's a fairly straight forward mild build. it should run really well.
 
That first cam might be a problem at the smog station. Since this is a daily driver with some freeway use, you want something that is going to get half way decent gas mileage too. The rear gears are fine for the milder cam and for the use you plan to put it to. You'll want to tap that intake for an EGR valve, or you will flunk the visual and you may not pass the NOX emissions. Verify that the new carb is Ca approved too. Depending on where you are in Ca. the truck may be put on the dyno for a more complete test and not just a minor butt sniff.
 
junkyardhero said:
i'm unclear on the intake and carb-- is that what you currently have or what you are planning on buying? if you currently have them, great. those are excellent for what you want to do.

i see no problem with doing some work on the heads. while it's all apart, and if it's within your budget i'd have a machine shop go thru and check them out and touch up the faces/seats, and drop new seals in. upgrade the springs to match your cam at the same time.

i would probably go with the middle cam, however none of those should get you into any trouble, they're not that wild. you can send yours out and have it reground and have the lifters reground at the same time-- oregon cams is a great place for that, and might even give a recommendation on a specific grind.

be sure to do a new timing set while you're threre.

the gears with those tall tires are gonna be kinda ho-hum, so if you can, maybe get on the hunt for some 3.55's at least. a slightly higher stall converter and shift kit would be a great upgrade as well.

other than that, it's a fairly straight forward mild build. it should run really well.
Click to expand...
Intake and carb I currently have. Yes to replacing timing set, and springs. What is a good range for a slightly higher stall converter? Do you know what the stall is on a factory/stock converter?

Thank you for the help.
 
cudamark said:
That first cam might be a problem at the smog station. Since this is a daily driver with some freeway use, you want something that is going to get half way decent gas mileage too. The rear gears are fine for the milder cam and for the use you plan to put it to. You'll want to tap that intake for an EGR valve, or you will flunk the visual and you may not pass the NOX emissions. Verify that the new carb is Ca approved too. Depending on where you are in Ca. the truck may be put on the dyno for a more complete test and not just a minor butt sniff.
Click to expand...
Alright, no on the first cam which is Lunatis' version of the factory 340 c.i. high performance cam. The carb is legal for sale and use on emission controlled vehicles. I didn't want to deal with the warping that can occur on the phenolic resin bodies of the thermoquads. So hence the bolt on replacement for the Quadrajet. Intake 3776 is already tapped for EGR.

Thank you for the help.
 
Heavy truck
Idle to 3500+ rpm normal duty
Check out Isky RV/Towing cam selection which will work with stock valve springs etc and pass those tests u are confronted with in CA !!
I have a similar vehicle and a simple intake carb and cam made a major difference!!
PS good luck with project.

IMG_20230721_171940_MP.jpg
 
stall speeds.jpg
re: stall speeds here's a chart i found someplace (probably moparts, sorry if i shamelessly pilfered this from somebody here).

i'd probably shoot for something in that low 2K range
 
The timing chain set looks to be an aftermarket one. I don't see any significant slack in the chain, so, if it's a good quality set, I'd reuse it. How many miles are on it?
 
One consideration - I have this and used summit (nos) older hyd lifters bought from a member and and a Offy dual port intake and small 4 barrel on low miles original (1976) 318 and I live at almost 4000 ft elevation and this rather small V8 handles everything pretty well.

Screenshot_20230729-222527.png
 
SS Lancer said:
Heavy truck
Idle to 3500+ rpm normal duty
Check out Isky RV/Towing cam selection which will work with stock valve springs etc and pass those tests u are confronted with in CA !!
I have a similar vehicle and a simple intake carb and cam made a major difference!!
PS good luck with project.

View attachment 1716120968
Click to expand...
I believe I found the Isky #390125/26?
Only thing is that the application calls for a higher rear axle ratio 3.55-4.10. However, I'm getting a good specification range to look at.

Is that an ex-forestry service truck?
 
Koadhen said:
I believe I found the Isky #390125/26?
Only thing is that the application calls for a higher rear axle ratio 3.55-4.10. However, I'm getting a good specification range to look at.

Is that an ex-forestry service truck?
Click to expand...
Army Ambulance
Power Wagon 886
Dana 60 rear HD 44 front
727
Just turned over 40 thousand miles
Factory manual steering with a big factory steering wheel.


Just turned over 40 thousand miles on it
 
Last edited by a moderator:
That's next on my list
When I come across some etc.
PS I do have 4.10 gears in my truck
So my combination actually turned out good for what I have to work with.
Koadhen said:
Wish I could run headers. There is a port on each manifold at the rear for a crossover tube that feeds to the air pump.
Click to expand...
 
cudamark said:
The timing chain set looks to be an aftermarket one. I don't see any significant slack in the chain, so, if it's a good quality set, I'd reuse it. How many miles are on it?
Click to expand...
You are right about the timing chain. The S-402 mark is from a Comp cams 2103 set...I am not sure about how many miles.
 
Just keep in mind with your state regulations it hinders your overall goal so make your money count with any upgrades.
Your camshaft and a single exh are two big restrictions your up against same as I was. Our camshafts (318s) smog era ones are embarrassing to say the least.
 
SS Lancer said:
Army Ambulance
Power Wagon 886
Dana 60 rear HD 44 front
727
Just turned over 40 thousand miles
Factory manual steering with a big factory steering wheel.


Just turned over 40 thousand miles on it
Click to expand...
Very nice rig...the patina is just right
 
If you're running manifolds, use a split pattern cam. That first cam in your original post is way too big for what you want to do.
 
I would say 'no thanks' to Holley & let them keep their carb......& install an Edel 650 AVS2 carb.
 
Bewy said:
I would say 'no thanks' to Holley & let them keep their carb......& install an Edel 650 AVS2 carb.
Click to expand...
no can do amigo, those aren't CA compliant. i think they have one or two of the performer series that are 50 state legal, though.

so realistically, considering he's got to deal with the smog officials, that's kind of his best choice short of hunting down a TQ or a Q-jet that would have the right numbers on it or at least pass the eyeball test.
 
You must log in or register to reply here.
-

Back
Top