A lil ? 68 300 with a 70 383. Needs tlc

kribs2714

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Good morning all I hope everybody's doing great I appreciate all opinions and I apologize this might get a little long new to this whole world recently purchased the 1968 Chrysler 300 convertible then says it's supposed to have a 4:40 with a four-barrel it's got a 383 with a two barrel trying to build up beef up the 383 to 4:40 stats or a little higher. Looking to make it a fun Cruiser it's already a beautiful ride getting some suspension work done I just wanted to have a little bit more oomph under that pedal. I understand it's big heavy car I also understand convertible and all the cross members that go with it. But I'm looking for any suggestions on how far to go or not to go on a build I should say on a budget build. I've read about the 496 build and it's good and it's not good I've read something about it not being a long lasting motor I forgot what the more experienced gentleman are called here but I look forward to any and all recommendations

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Just put a 440 back in there. 383 is great but it's no 440.
It's all about torque to move the weight.
383 has a 3.38 stroke
440 has a 3.75 stroke.

Rear axle ratio is critical with a no power engine like a 383 2 bbl. 2.76 will make that heavy car a real dog.

Post your fender tag and it has the axle code on it. At least what Chrysler put in there, it could have been changed out.
 
Beautiful car in a beautiful color combination!

ONE thing people who have stroker motors never mention is MPG. They usually mention "size" but not what it takes to "feed it". Most are not "distance cruisers" for that reason, I suspect. And that was before gas prices got to where they have been for the past decade or so. BTAIM

With a car that looks that good, a mere 383 4bbl will be fine. You DON'T have to prove anything with a big motor as the car will get enough positive attention without anybody knowing what's under the hood. 2bbl carbs, too, are fine. Only costing "power" above 3000rpm. Guess where the bulk of your driving is, under 3000rpm. The primaries of a 600cfm carb are the same size as the throttle bores of your existing 2bbl carb.

To me, the bulk of the performance of modern V-8s is due to the fact they are always in front of an 8-speed automatic, which has a very deep low gear ratio, for "great launch" (as the factory guys term it) off-idle. Once underway, the 3rd gear and above keep the engine in s particular power band that is usually narrower then what it was on the older engines. So faster acceleration with the top 3 gears being overdrives, which is why they get the fuel economy they do on the highway.

The car should already have the 3.23 rear axle ratio in it, which can help things a bit without hurting fuel economy too much on the highway. 1970 383 2bbls already have the cam as the 383 4bbls anyway. So just need a good dual exhaust under it, basically.

Easy upgrade would be an Edelbrock Performer intake with a 625cfm Edelbrock AVS2 carb. A better venturi design than what would have been on the car to start with and a 4bbl intake that is as good as the OEM Chrysler 4bbl intakes, if not a few horsepower better. An electronic ignition, if not already there, can round things out.

An easy stroker upgrade would be to use a rotating assy with a 3.75" stroke (same as the 440) that should make about 450cid. That should yield more lower rpm torque than any similar 383 might build. Some might argue that you might as well and "go big", but at what additional cost? NOT just in engine build costs, but also in related chassis upgrades to be able to use that additional power of the 500cid V-8. No sense in paying for it if you're not going to use it! This gets into NOT ONLY tires, but brakes and rear suspension, too.

Remember, too, you've got a convertible body which is not nearly as structurally stiff as the normal sedans most of the strokers find themselves in. "Torque Twist" is the enemy! LOTS of little side issues!

In the mean time, learn about the car and what made it better than similar GM cars. Make sure that somebody tunes it that will tune it to stock specs and ensure it is running as good as it can. Even to lay a bit of rubber, if desired. The allegedly-popular giant smoky burnouts or similar are NOT a part of that car's heritage, although some can do that if the driver know what they are doing.

Because the car is as good looking as it is, you don't need to impress ANYBODY with a huge motor under the hood. Be a good steward of the car while you own it. Which means keeping it as stock and good looking as you can. Certainly, a few things can be changed, but too many of them detract from things, by observation.

Enjoy!
CBODY67
 
What are your goals for the car? You want a beast or something that gets up and goes better than the 2bbl 383?

What you already have can be made to run pretty good, reliably without much hassle.
 
Nice ride, love that color combo!

If you want to do something in a small budget maybe consider starting simple with an intake and a four barrel. Or, if your skill set allows, maybe you can find a 440 from a motor home at a junkyard and drop it in.

I would also consider headers but they seem like a huge PITA to work around once installed.

If you are considering pulling and replacing, and you do have the budget and the skills, a newer engine with Fuel Injection could be an option.

Another thought would be to keep the 383 and change your rear gear ratio and swap in a different transmission with OD. Might be the best of both worlds.

I would spend some time thinking about what you want from the car and try to work towards that instead of just putting a 440 back.

Good luck, enjoy the ride!
 
The 383 is a darn good engine and with a 4 bbl. carb and dual exhaust will make plenty of power. 440s are getting hard to find, and if you do find one it may need to be rebuilt anyway.
 
Just my 2 cents, my 69 Newport still has her original 383. All we have done is put a 4 barrel on her. She has plenty of power. Leave yours as she is for now and enjoy her. If at some point you pull the car down for some major work, then think about adding the 440.

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Yep, I'll admit it, I'm "old" in body in some respects, with respect to others in here. "Young" is other ways.

I'm old enough to remember 13 cent/gallon GulfTane (the original sub-regular octane level) gas of the middle 1960s, when I was in Junior High School. I remember how the gas prices escalated and purchases restricted (as to amount per purchase, due to rationing) during the fuel embargo of 1974. When people with larger cars (and 25 gallon tanks) saw the cost to fill the tank rise to levels unseen at that time. One national lodging chain (now gone, Days Inn) put in gas pumps at their motels so that guests could fill up before they left the next morning.

I also remember how the company shuttle bus was crowded as people went out to eat at lunch, but when local gas prices hit $2.00/gallon, that "crowd" was observed to be bringing brown bags for lunch, consistently.

Most current cars now only have 16-18 gallon fuel tanks compared to the prior (up to 26.5 gallon tanks, in some cases), and get much better fuel economy than back then. Not a big deal to only buy 8-9 gallons at a time, for me, keeping the transaction prices lower. This also ensures I don't drive around with a tank full of higher-priced gas during the typical 40cent/gallon fuel prices spikes in this area. So I enjoy the decreases, but also noting signals the price will be spiked by the next morning.

My sensitivities to these things might be different from others of any age. For young people, these prices and variations are their "norm", as that's what they are growing up with. Which also relates to generations which came along after I was born. Just the way things are, whether it is fuel prices, climate issues, or other things.

One thing I liked about Chrysler products was that they generally got better fuel economy on trips than similar Ford or GM cars. Might have been 17mpg rather than 15mpg, but it was better, ro do the same things with less money. When I say "trips", I'm talking about "hours" rather than "minutes" of higher-speed Interstate highway travel, rather than a leisurely "drive in the country on a Sunday afternoon". So fuel costs to do these things have always been important to me, throughout my advancing-age life. I prefer highway cruising rather than 1/8 or 1/4 mile sprints from a stopped position. Just my preferences.

I have also witnessed the OEM 500cid engines from Cadillac and such. Plus the Chevy 502s in 3/4ton pickup trucks. In the case of the Cadillac 472/500, the consensus was that if you could afford one of those cars, you could afford the fuel it took to drive them, but in the case of the 502 Chevies, those were "work trucks" and usually pulled heavier trailers to the job sites.

The amusing thing on the Chevies was that many bought them with a manual transmission, with the (not admitted to) intent of expecting to do giant smokey dually burnouts. They soon discovered that the computer would not allow that, decreasing power to save the drivetrain. But the automatics, in gear, would do burnouts. Try a neutal-drop, no fun. There were also some "secret codes" in the vehicle computer memory of such things being tried, too.

Perhaps I'm being a bit too "logical", but with the millions of new residents into the DFW area in the past 20 years, previously empty massive freeways are now full of 35mph parking lots several times a day. The formerly-country roads where we used to be able to safely "play" or "do testing" are now wider and lined with $400K+ residences. Traffic density has increased to where it is hard to find an open stretch of road anymore, without driving over an hour to get there. All of the formerly-local area drag strips are now covered in homes. All of these things can tend to make owning a big stroker motor just a talking point of sorts. An expensive one.

NOW I do appreciate all of the modern tech that went into making these motors and the power they can produce when done, but as to really enjoying them, fewer and fewer places to do that every month, where I am. Population will keep expanding, no matter what.

A guy in our Mopar club is building a 543 stroker 440 for an Imperial he has. When done, it will be fully-modern in all aspects as to computerized engine management systems. Sitting in front of a ZF 8-speed automatic. He's in his later 40s and can afford those things. I'm glad for him! He can also afford "good for the size" highway fuel economy, too.

But a 383 will cruise down the highway at 75-90mph just fine, for me. With tire prices also escalating worse that gas prices, "laying rubber" has diminished greatly, for me. Used to be that was a "mark of power", but with all of the turbo 4-cyls and 10-speed automatics (and their deep low gears), "anybody" can do it now, it seems. Heck, even my '05 Buick 200 horsepower V-6 will set the Michelins to "being noisy", if I turn off the Traction Control. With a "crude" 4-speed automatic.

Sorry for the length! I know that everybody can have different orientations and sensitivities on these things, for various reasons, and I respect that. Some of these sensitivities can even be generational, by observation. Everybody's "history" can be different.

Y'all enjoy!
CBODY67
 
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Good morning all I hope everybody's doing great I appreciate all opinions and I apologize this might get a little long new to this whole world recently purchased the 1968 Chrysler 300 convertible then says it's supposed to have a 4:40 with a four-barrel it's got a 383 with a two barrel trying to build up beef up the 383 to 4:40 stats or a little higher. Looking to make it a fun Cruiser it's already a beautiful ride getting some suspension work done I just wanted to have a little bit more oomph under that pedal. I understand it's big heavy car I also understand convertible and all the cross members that go with it. But I'm looking for any suggestions on how far to go or not to go on a build I should say on a budget build. I've read about the 496 build and it's good and it's not good I've read something about it not being a long lasting motor I forgot what the more experienced gentleman are called here but I look forward to any and all recommendations

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My 2 cents (which is now 8 bucks due to inflation) is to keep it as is and enjoy it for now. Then, look for a 440 engine or even just a short block. If you find a short block, you can have that rebuilt. When that's done, pull the 383 out, pull the heads off the 383 (assuming they aren't some old small valves) and have those redone (valve job etc.) and the oil pan/pickup along with other externals. You'll have to find an intake and carb if you go this route, but you may have to with a later complete engine too. Clean the engine bay while this is happening. Bolt it all together and go enjoy it. Minimal time off the road and probably cheapest way to add a fresh 440.

The big inch engines are great, but they are going to be more money to build and drink more premium gas. It's still a heavy convertible... and you probably aren't going racing. A 'vert is meant for cruising and really it's more enjoyable when the engine is mild rather than wild.
 
What are your goals for the car? You want a beast or something that gets up and goes better than the 2bbl 383?

What you already have can be made to run pretty good, reliably without much hassle.
I'm not looking to build a beast I don't want people to hear a cam a block away I just wanted to breathe a little better that's all and I do understand about the miles per gallon. I believe it's a 323 I will add in the fender tag and anybody that can help me with that I would appreciate and I thank all of you for all of the help and opinions and everything she is a beautiful you're right I don't know anybody anything I just want a little bit more when you go to give it a little bit of goose on that nice curvy Road
 
Big John hit the nail on the head and pretty much covered what we discussed yesterday. That's the route I'd go personally so the engine doesn't come out, and the car sits waiting to be back together.
 
Big John hit the nail on the head and pretty much covered what we discussed yesterday. That's the route I'd go personally so the engine doesn't come out, and the car sits waiting to be back together.
You disagreed to my reply that was echoed by Big John to which you then agreed with...:poke:
 
I'd leave it as is.

The only thing you will gain by putting a 440 in it is telling people it has a 440 in it.

Burn outs are for children.
 
I'm not looking to build a beast I don't want people to hear a cam a block away I just wanted to breathe a little better that's all and I do understand about the miles per gallon. I believe it's a 323 I will add in the fender tag and anybody that can help me with that I would appreciate and I thank all of you for all of the help and opinions and everything she is a beautiful you're right I don't know anybody anything I just want a little bit more when you go to give it a little bit of goose on that nice curvy Road
You disagreed to my reply that was echoed by Big John to which you then agreed with...:poke:
I didn't even notice I reacted there
 
I'm not looking to build a beast I don't want people to hear a cam a block away I just wanted to breathe a little better that's all and I do understand about the miles per gallon. I believe it's a 323 I will add in the fender tag and anybody that can help me with that I would appreciate and I thank all of you for allof the help and opinions and everything she is a beautiful you're right I don't knoanything I just want a little bit more when you go to give it a little bit of goose on that nice curvy Road

I think your 383 probably has a decent cam and heads. If the diff is really a 3:23, you are getting pretty close to a good setup. Get an Edelbrock carb and a distributor with a good curve and install dual exhaust. You will be very happy with the results.
 
Does that mean drag racings for children? I like a good ole fashioned burnout with a nice set of marks and im 62!
 
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