Advice on my "stock" 340 build

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mad dog

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Good morning FABO..
Im getting ready to bring my 1969 340 to the machine shop for a "stock" rebuild, it wont be 100% stock but pretty close.
I always read to build the car to your expectations and driving style, so if thats true then a stock rebuild suits me just fine.
I love the thread that @RustyRatRod started about hot rod bliss and keeping it simple and i want to see/feel what all the hype was like back in the 60-70's
my goal is to have a great reliable 340 to stuff into my Duster/auto/355...

I want to mimic the 1968 340 specs, so far ive aquired
1. 1969 block and crank
2. X heads and original intake, hope to use the original carb also, needs rebuild
3. 1968 4-speed cam from Oregon Cam
4. 273 adjustable rockers with grooves
5. 355 rear ..8.75
6. re-cored HD 22" radiator So im looking for advice to make this "stock" 340 run really great, im not trying to squeeze every last drop of HP out of it... im more thinking on how to improve on an already great platform. what tips and tricks can i tell my engine builder to do.
i have always heard that some 340's ran better than others, im also interested in any cooling suggestions, in the past ive spent more time staring at the temp gauge than enjoying the ride .
I hope ive accurately described what type of build im after, I am not a mechanic, I do a lot of my own restoration stuff with the help from @davescuda but im not engine building savy so I hope you guys will suggest machining improvements and any tips so i can cruise this summer with piece of mind.. Thanks for reading and i will await your 340 knowledge...Rich
 
I forgot to add that my last 340 and 440 builds I used FBO ignitions, im probably going to use them again..Rich
 
All my 68 4spd Darts had 391's with 14 inch bias tires. usually up graded to G60 rubber That is when the experience was a hand full of fun. Low gears, little tires . The 440's 4spds with 410's and G78's many of them never made it past the test drives. The first thing you did with those was Slicks. But don't drive them in the rain no matter how much weight was in the car.
 
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First off, good luck with your build. Sounds like a fun build and you are in the process of a well thought out one. I would go with a 71 stock cast iron intake manifold and a thermoquad carburetor. Aftermarket aluminum heads my be a cheaper way to go especially if you can pick up a used set of heads at a good price. I would also consider porting the heads and intake manifold and also the exhaust manifolds if you do not go with headers by a good porter like Charles Servedio.
 
We always kinda theorized that the reason some engines (of all makes) ran better than others was perhaps because the factory would build some blueprinted to spec for a kinda "comparison" test. Sounds good anyway. We all know how the factory engines were all under their advertised compression ratios, some by a good bit. Taller than spec deck heights, bigger than spec combustion chambers. And on and on. The 68 340 with a 71 induction system is the hybrid I've always wanted to do. Blueprint everything. Deck height, all the chamber volumes, Index the crank, just get all of the machine work "perfect". Degree the cam 4 degrees advanced, as you know that was never done. You have the great Mopar electronic ignition you could use and you want FBO junk? No way in hell would I run that. It's crap on a stick and you'll get no support of any kind. That's his reputation. I think you'd be happier with a Mopar ignition with a good loose curve, but it's your money. Waste it as you see fit. lol
 
some reasons some run better than others is how they are driven and maintained.
*Need to be driven hard to seat rings
*choke is set too rich it washes down the cylinders.
*seldom or never changed the oil that takes a toll
*drive on short trips in winter with choke on and never warm it up
*warm it up before you run it hard.
*keep oil clean and full

I worked at dealerships and never understood all the cars in for warranty oil leaks. I bought a 1992 car new and it still has original gaskets including valve cover gaskets, never leaked, 90K now.
 
if you're trying to replicate the experience as it was back in the days of yore, then you seem well on the way.

the basics apply to any build: attention to detail, machine work that is en point and careful selection of parts both in quality and compliment go a long, long ways toward building a motor that's better than the average bear.

that being said, unless it was a straight up stock build for a numbers car i'd eschew a lot of the yesteryear and lay down for some of the modern conveyance and reap what has been sown with regard to todays components.

better, lighter pistons with modern ring packs, beehive springs, lighter valves with smaller stems, modernized heads, roller rockers, camshafts with modern grinds and better lobes, carbs that have evolved and are flexible and tuneable across a broader range, headers that fit and function properly.

now there's nothing wrong with a stock 340, especially one that's been blueprinted. it'll run like a striped *** ape. but you have to remember that everything that ma mopar did had a factor of compromise in it. you're uninhibited to build something better if you so choose.
 
I built a similar engine last year. It has only run on the test stand. I too wanted to keep it fairly stock and went with the Oregon 68 4 speed cam installed 2 degrees advanced with stock rocker gear. The stock heads were rebuilt with nail head valves which reduced the combustion chamber volume down to 63 cc for 9.75:1 compression. I didn't have a stock manifold or carb so went with the Eddy RPM (non air gap) and Eddy 650AVS. Everything else is stock except ARP rod bolts. I have a 4 speed with the low 1st gear, 3:55s and stock 14" rear tire size. I hope it works out :)
 
1MeanA said:
I built a similar engine last year. It has only run on the test stand. I too wanted to keep it fairly stock and went with the Oregon 68 4 speed cam installed 2 degrees advanced with stock rocker gear. The stock heads were rebuilt with nail head valves which reduced the combustion chamber volume down to 63 cc for 9.75:1 compression. I didn't have a stock manifold or carb so went with the Eddy RPM (non air gap) and Eddy 650AVS. Everything else is stock except ARP rod bolts. I have a 4 speed with the low 1st gear, 3:55s and stock 14" rear tire size. I hope it works out :)
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i know you said that its only run on the stand but what was your impression, anything you wish you would of done diferently or is it too soon to tell...Rich
 
mad dog said:
i know you said that its only run on the stand but what was your impression, anything you wish you would of done diferently or is it too soon to tell...Rich
Click to expand...
The only thing I thought about was running a cam with more lope but then the objective was to run something close to factory stock.
ps I did use the Mancini performance distributor and electronic ignition of course
 
mad dog said:
Good morning FABO..
Im getting ready to bring my 1969 340 to the machine shop for a "stock" rebuild, it wont be 100% stock but pretty close.
I always read to build the car to your expectations and driving style, so if thats true then a stock rebuild suits me just fine.
I love the thread that @RustyRatRod started about hot rod bliss and keeping it simple and i want to see/feel what all the hype was like back in the 60-70's
my goal is to have a great reliable 340 to stuff into my Duster/auto/355...

I want to mimic the 1968 340 specs, so far ive aquired
1. 1969 block and crank
2. X heads and original intake, hope to use the original carb also, needs rebuild
3. 1968 4-speed cam from Oregon Cam
4. 273 adjustable rockers with grooves
5. 355 rear ..8.75
6. re-cored HD 22" radiator So im looking for advice to make this "stock" 340 run really great, im not trying to squeeze every last drop of HP out of it... im more thinking on how to improve on an already great platform. what tips and tricks can i tell my engine builder to do.
i have always heard that some 340's ran better than others, im also interested in any cooling suggestions, in the past ive spent more time staring at the temp gauge than enjoying the ride .
I hope ive accurately described what type of build im after, I am not a mechanic, I do a lot of my own restoration stuff with the help from @davescuda but im not engine building savy so I hope you guys will suggest machining improvements and any tips so i can cruise this summer with piece of mind.. Thanks for reading and i will await your 340 knowledge...Rich
Click to expand...

I'm finally getting my 340 built this winter, still not sure what it will go in.

69 340 block bored + .020 and honed with torque plates, decked just enough to clean them up
Standard 340 shot peened crank
+ .020 NOS Chrysler "72" lower compression 340 pistons
stock 340 rods, reconditioned with Direct Connection Rod bolts and nuts
Total Seal gapless top ring set
Custom Racer Brown solid lifter cam, 214 duration @ .050, .450 lift on a 105* intake centerline.
Direct Connection intermediate shaft
High Volume, High Pressure spring oil pump
Windage Tray

Original 2.02 intake J heads milled .020 and .019 on the intake side, chambers cc'd and equal within + or _ .1 cc bowl and general cleanup, gasket match ports except the bottoms.
Milodon Stainless Valves
stock 340 valve springs
Fel-Pro Viton positive valve guide seals
chrome molly retainers
Fel-Pro Gaskets

Either a "71" 340 or an Offy Port-O-Sonic intake with a "72" 340 TQ
Direct Connection distributor with a chrome box
3 row original radiator
5 blade aluminum fan with thermal drive
 
I'd op for making sure it comes out to a true 10.5 to 1 if you don't mind mixing your fuel. A set of crane 1.6 rockers. Set the timing to 36 total. Run vacuum advance at your own risk.
 
Guys you have given me some sound advice, thank you...
my next question is concerning the lifters, I need a set for the 340 and with all the talk about subpar lifters they are selling these days would you recommend that i place a wanted ad for used lifters and then have them re-faced?
 
mad dog said:
Guys you have given me some sound advice, thank you...
my next question is concerning the lifters, I need a set for the 340 and with all the talk about subpar lifters they are selling these days would you recommend that i place a wanted ad for used lifters and then have them re-faced?
Click to expand...
melling makes good stuff and what i've been using. morel is another choice for a top quality lifter and their price reflects that. enginetech is another company that offers quality at a good price point.
 
mad dog said:
Guys you have given me some sound advice, thank you...
my next question is concerning the lifters, I need a set for the 340 and with all the talk about subpar lifters they are selling these days would you recommend that i place a wanted ad for used lifters and then have them re-faced?
Click to expand...
Delta Cams in Wa. provided a set of hydraulic lifters for my small block build and they worked out well. Also they refaced some edm Howards solid lifters for me with good results.
 
mad dog said:
Guys you have given me some sound advice, thank you...
my next question is concerning the lifters, I need a set for the 340 and with all the talk about subpar lifters they are selling these days would you recommend that i place a wanted ad for used lifters and then have them re-faced?
Click to expand...
Oregon Cams provided me with Federal Mogul lifters for that is worth. I have a used set of unknown lifters that are at least 20 years old if you are interested.
 
Hope everyone had a great xmas, ive been thinking about sending my carb out for a restoration for this stock 340 build, i have 2 to choose from and not sure which one would be better
1. 1969 4611S Which is the 69 4-speed carb...or
2. 1970 4937S Which is auto w/ecs.
any help would be appreciated, right now im thinking about these 2 and not buying a brand new carb, your thoughts?

Also im thinking about taking RRR advice and use an OEM ignition system, thinking about the 72-73 electronic unit, maybe our resident distributor guru can set me up with a whole kit, distributor, harness,ballast resistor and a ECU (what color box ?)

Thanks for reading and the help, all suggestions are welcome...Rich
 
im trying to maintain a factory stock build and appearance
 
1MeanA said:
just buy an Edelbrock AVS650 and a Mancini distributor and ECU.
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I don't know man. I've really been SOLD on the Blueprint Engines distributors. They are MSD knockoffs, but they are NICE. I have direct very recent experience with one in a Chevy small block. Except for the wires attaching to the coil and the tach wire, it is a ONE WIRE ignition system. Adjustable mechanical and vacuum advance just like MSD. No control box required.
 
mad dog said:
im trying to maintain a factory stock build and appearance
Click to expand...
The Blueprint distributor is almost 100% indistinguishable from stock. The only main difference in appearance is the male HEI terminals on the cap and they are hidden when the wires are installed. @Johnny Mac can chime in and tell you more.
 
mad dog said:
Hope everyone had a great xmas, ive been thinking about sending my carb out for a restoration for this stock 340 build, i have 2 to choose from and not sure which one would be better
1. 1969 4611S Which is the 69 4-speed carb...or
2. 1970 4937S Which is auto w/ecs.
any help would be appreciated, right now im thinking about these 2 and not buying a brand new carb, your thoughts?

Also im thinking about taking RRR advice and use an OEM ignition system, thinking about the 72-73 electronic unit, maybe our resident distributor guru can set me up with a whole kit, distributor, harness,ballast resistor and a ECU (what color box ?)

Thanks for reading and the help, all suggestions are welcome...Rich
Click to expand...
Rebuild the 4937s carb. I have never run a new carb. The "70" 340 carb should work fine for your combination. I like the OEM electronic ignition. Any good old box will work to 6,000 rpm. Some of the orange boxes were bad and the chrome boxes are good forever. I'd get a complete setup from Halifax hops. You can also run any 72-73 electronic 340 distributor or the Direct connection electronic # P3690430 distributor.
 
so i asked my engine rebuilder about what lifters he will use on my 340, he replied johnson hy-lift... do you guys think thats a good choice or should i place a wanted ad for some used 340 lifters and have them re-surfaced?
my engine guy said hes never had a problem with them....
 
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