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Best way to start on my 383 '68 Newport

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Mugwamp8

Sun Nov 22 2009, 02:42PM

[ 318 2brl ]

Registered Member #2444
Joined Wed Oct 14 2009, 07:20PM
Location: Florida
posts 75

Hi Everyone,
I am pretty new to the car world and may be asking a question that is a bit ignorant but here goes. I recently posted a question about what wires and plugs to use on my 68 Newport. Now that that is done I want to keep the upgrades moving along in the right direction. The car has teh original 68 Motor in it as far as I know. When I bought it I was told that a few "upgrades" had been done. It now has a 4 barrel out of a 61 Imperial(I think) and 2 and 1/2 inch dual exhaust. The cam was changed to a "mopar performance" cam but I don't know anything more about it. The wires and plugs, points, tune-up, and basic maintenance have just been completed from a local mechanic (I bought the original shop manual off of ebay). I'd like to start doing some upgrades that will get some more power since I've heard you can squeeze a little more out of these motors. What should I do next? Does anyone have a good "recipe" that I can follow in order? I don't want to buy something now and then have to change it down the road. I am hoping I can slowly build on each upgrade and increasingly be happy. The article I've been thinking about is: http://www.moparmusclemagazine.com/techarticles/mopp_0209_383_engine_restore/index.html Can anyone that understands this stuff check it out and let meknow if I should follow this? I am not sure if this is really for a stock 383 like mine. If this is a bad "recipe" can someone steer me in the correct direction to get some more horsepower out of this motor? The article mentions an M1 intake and 850 Demon Carb. Is that what I should get first? I appreciate any knowledgable advice on this. Also, I recently noticed that my car has a slight pull to the right when you are accelerating. I got the tires rotated and then she slightly pulled to the center line. I figured I'd have the local tire shop give her an alignment but when I took it there they said I need a right lower balljoint. On the lift the guy pried something apart and said "see the play here and not on the other side." Does this seem like a symptom of a ball joint? I noticed www.justsuspension.com has big 600 dollar packages. Anyone know where I can get just the ball joint? Everyone has uppers and not lowers online. Should I just save up for the whole front end package? Thanks for any advice on these issues so I don't waste my money. Have a great Thanksgiving!

joe383

Sun Nov 22 2009, 03:47PM

[ 318 2brl ]

Registered Member #2435
Joined: Fri Oct 09 2009, 09:27PM
Location: yakima
posts 65

I like to run electric fans they free up a little power. Also I would not totally focus on just the motor if you have highway gearing 2.73 or close I would have the rear gears switched to something closer to 3.55 and run a 2,000 rpm stall in the transmission with a street strip shift kit. I would run an aluminum duel plane intake it will take a little weight off of the front of the car and add a little power. Headers would be good if you can locate a pair and an electronic ignition if you don’t all ready have one although I have not noticed much gain in power from ignition mods I have noticed better fuel economy and throttle response.

All stock doing resto mod.

Krautmaster

Sun Nov 22 2009, 08:13PM

[ Blown 500 Stroker ]

Registered Member #1644
Joined: Wed Jul 23 2008, 07:53PM
Location: Phoenix AZ
posts 2206

First off, you have to ask yourself what you intend to do with your car, and then determine how much money you have to spend to get there. Are you just going to bolt stuff onto your used engine, or are you going to completely rebuild it ? Do you want a highway cruiser or a street/strip performer? Or are you considering going for an all out racing build?

The article you reference has some good ideas, but some of the parts they used won't work well on a street driven 383. What rear axle ratio does your car have? Since most 383 2bbl Newports had 2.76 highway gears and a low rpm stall converter (1800 rpm), a Demon 850 carb is just overkill on a car like that, as is the M-1 intake--it would run poorly until you got the revs up pretty high.

What your car needs is lots of low end torque, so you would be far happier using an Edelbrock Performer or Performer RPM intake manifold and an Edelbrock 750 cfm carb. The cam you have may also be the completely wrong grind for what you need--see if you can out what grind it is, and note that any cam that has more than 268/284* duration is too much for a heavy, high geared car without first changing both the torque converter and rear gears.

Since you car already has 2.5" dual exhausts, you will need to upgrade to some factory HP exhaust manifolds or tube headers so it will be able to breathe. Then get a Melling high volume oil pump and use 6 quarts of oil.

I repair /rebuild old big block Mopars in my spare time to earn some extra $$, and have a typical build for 383's that doesn't cost too much (unless your engine needs a complete rebuild--then it gets pricey for the machine work and new pistons). Here is a quick parts list:

1) Comp Cams Extreme Energy XE268H cam with matching lifters
2) Comp #911 valve springs, new Mopar Performance rocker arms/shafts, and pushrods
3) Have a good machine shop do a three angle valve job on your heads
3) Double Roller timing chain set
4) Melling High Volume oil pump (use 6 quart of oil)
5) Mopar Performance windage tray
6) ARP rod bolts - have machine shop resize and shot peen the rods
7) Edelbrock Performer RPM intake manifold

Edelbrock Performer 750 cfm carb (#1407) or Edelbrock Thunder AVS 750 cfm carb (#1807)
9) Factory HP exhaust manifolds and 2.5" dual exhaust with H pipe.
10) Moly coated piston rings
11) Complete Felpro gasket set

This generally nets 340-390 Horsepower, depending on the condition of you engine to start with (old tired engines make a lot less power than freshly bored ones with new pistons) and works wonderfully on cars with stock torque converters and 2.76 or 3.23 gears. 440's respond good to this too, but they can use a hotter cam before having to upgrade the converter and gears.

[ Edited Sun Nov 22 2009, 07:34PM ]

Krautmaster-Phoenix AZ
'68 Newport Convertible
swiss goes great
with baloney

owatajrkiam

Sun Nov 22 2009, 09:22PM

[ Blown 500 Stroker ]

Registered Member #296
Joined: Tue Feb 07 2006, 10:39PM
Location: Winnipeg,Manitoba, Canada
posts 2450

What Krautmaster say's is good advice!. In the article,the headers are 1 7/8" but for a heavier car without steep gears and a loose converter,you want to go with the 1 5/8" headers as it will keep a little more back pressure to the valves. I guess you're next,minor step could be the timing chain. The reason i'm saying this is because,if you go in there and replace all the gaskets,new waterpump and the timing set with a quality 3-way true roller setup you will find a number marked on the front of the camshaft snout. Once you know what the cam is,..it will determine the rest of the build. Some of the purple cams from MP are fairly good,...the Comp Cam XE's that Kraut was talking about are built on the .904" diameter lifters and require a good spring,but...you will love the power that they make as the MP cams cannot compete with them. You will have to pull a valve cover and bump the cam to #1 TDC and check to see how much closed spring clearance there is with a feeler gauge once you know the specs. of the cam. Don't go throwing in a new cam without knowing what kind of clearance you have. Better yet....if you do a cam change....follow their recomendation.

Glen

[ Edited Sun Nov 22 2009, 08:27PM ]

67dodgeboat

Sun Nov 22 2009, 09:42PM

[ 360 2brl ]

Registered Member #1745
Joined: Wed Oct 08 2008, 09:53PM
Location: Coon Rapids, Minnesota
posts 168

If you go with an edelbrock performer carb make sure to get the manual choke carb because it comes pre tuned for a little more performance than the auto choke ones. When you get the carb. make sure to get the auto choke conversion kit, if not you will have a very difficult manual choke carb to keep tuned. putting the conversion kit in is really simple and it only requires running one wire. doing this requires that you get the best of both worlds: a little extra performance straight from edelbrock, and the simplicity of the auto choke carb. I learned from experience. Good luck

67 Monaco 2 dr. 383
69 Fury III 4 dr. 318

furious70

Mon Nov 23 2009, 11:44AM

[ 426 Hemi CrossRam ]

Registered Member #1523
Joined: Thu May 01 2008, 11:15AM
Location: Chicago,IL
posts 1531

Does the car lope at all at idle? You probably just have the resto muscle car purpleshaft in there I'd guess, which will be ok for what you're doing. That article is worth it's weight in gold for telling you what each step will do to the engine. I'm like Kraut, I would stop short of their big end pieces, put a dual plane intake and a 750 carb on it with headers and you'll be really happy with how it runs. A change from 2.73 to 3.23 gears if you don't do a lot of interstate driving is good bang for the buck as well.

Mugwamp8

Mon Nov 23 2009, 09:27PM

[ 318 2brl ]

Registered Member #2444
Joined: Wed Oct 14 2009, 07:20PM
Location: Florida
posts 75

Thanks! I'm going to email the guy I bought it off of and hopefully find the specifics of the cam. The edelbrock set sounds like the way to go. What is the difference between the dual and single plane intakes?

Krautmaster

Mon Nov 23 2009, 09:59PM

[ Blown 500 Stroker ]

Registered Member #1644
Joined: Wed Jul 23 2008, 07:53PM
Location: Phoenix AZ
posts 2206

Dual plane is for low-mid rpm power/torque, single plane is for high rpm power. The Edelbrock Performer RPM will give you the best of both.

Krautmaster-Phoenix AZ
'68 Newport Convertible
swiss goes great
with baloney

joe383

Mon Nov 23 2009, 10:10PM

[ 318 2brl ]

Registered Member #2435
Joined: Fri Oct 09 2009, 09:27PM
Location: yakima
posts 65

Duel planes usually have better low rpm throttle response, low rpm torque and idle better and single planes are better for high RPM. I would go with a Performer RPM Air Gap and Edelbrock 750 they would work great with just about any cam you might have.

All stock doing resto mod.

Krautmaster

Mon Nov 23 2009, 11:53PM

[ Blown 500 Stroker ]

Registered Member #1644
Joined: Wed Jul 23 2008, 07:53PM
Location: Phoenix AZ
posts 2206

The Air Gap manifolds are only for small blocks -- all '68 Chryslers were big blocks--you need the Performer RPM, part number 7186.

Krautmaster-Phoenix AZ
'68 Newport Convertible
swiss goes great
with baloney

Uncle Joe

Tue Nov 24 2009, 11:33AM

[ 383 4brl ]

Registered Member #854
Joined: Thu Mar 22 2007, 08:13AM
Location: Sweden
posts 333

After reading this thread, I realise how things have changed over the years! Way back in the mists of time, when I became interested in US built cars, the manifold to have seemed to be the Edelbrock Tarantula. Then came the Torker, which was considered at the time one of the best available for street cars. Despite it being a single plane, air gap type! At that time, I wouldnt have considered any other manifold for a car! In fact, when I bought my current Mopar, I fitted one that I have had lying on the shelf since the mid 70's! It has since been replaced though...!

Now that I've stopped being nostalgic, I will say that a dual plane is probably best for street use, IMHO, of course...

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