Cam swap worth it? '68 383 newport

[Ripinator]

Which torque converter did you get with your combo, and you have 3.23 gears right?
Swapping the 2.76's to 3.23's and dual exhaust is on the list of first upgrades after the car is driveable.

I know that a cam ties everything together. I've build my own engine for my VW beetle. A 1.9L big bore engine with a great torque curve and good horsepower. All the machine work including milling the shortblock to fit the bigger pistons and cylinders (single barrels) was done in house by myself. I can find my way around with old VW aircooled engines, but big american v8's is new for me.

This is also the reason why I'm asking, I want a cam that fits my combo just right. And I was curious to hear some info and opinions on this forum All to get new info, learn and make better decisions.



+1 for Steve Dulcich. I like that man very much. Thanks for the info.



Please, keep on rambling. If it's useful information I'll have it all

The 268H seems a bit on the smaller size? For engines from 8:1 to 9:1 compression and "only" 218 @.050 on intake and exhaust. Nevertheless, thanks for the info. It's worth comparing everthing. This makes it easier for me to find something that will be in the ballpark.

How big can you go with a cam before you run into issues with the stock converter with a heavy '68 newport? It currenly has 2.76 gears but I'm considering a swap to 3.23's.



Thanks for the message again. Hughes looks good. I will send them a message to get some info for my specific combo.



Thanks for the input also



Another one for Hughes. Great!


So I was just thinking of a cam swap for now with future upgrades like dual exhaust and swapping 2.76's in the rear end for 3.23. Do I also need to consider a different converter with these changes? I have no idea what the specs of the stock converter are and how to pick one. Everything I had so far is stick shift.

One more thing I think no one has mentioned: If you go with a cam with excessive overlap (too much rumpity rump), you will pull less vacuum, and that will negatively affect power brake performance.

 

[cbarge]

Which torque converter did you get with your combo, and you have 3.23 gears right?
Swapping the 2.76's to 3.23's and dual exhaust is on the list of first upgrades after the car is driveable.

Light stall nothing agressive. I think 2250-2500 if I can remember..but in a big heavy car feels like stock.
However,I added the part throttle 3-2 kickdown to my trans and a shift kit. Very efficient and works very well with the torque curve from the motor. This mod alone even with stock convertor is a huge improvement.
Where I do a ton of highway driving I am running 2.94 gears poached out of a 66 318 Satellite. Not much difference between that and 3.23 gears when running a 2357015 tire. Keeps the revs down on the highway by 500 RPM vs the 3.23's.

To answer another question the 268 cam is the largest to work with stock convertor.
I have power brakes and my vacuum runs between 15-17 inches. The booster needs minimum of 9-10 inches of vacuum.
But 12 and up is where I like to be.
Hope this helps

 

[cbarge]

727 3-2 Kick Down Module (1966-69) - A&A Transmissions
Run this if you have the original trans

 

[jct]

That shop is local to me

 

[Metalmarty]

Going by what you're saying you want, yes, I would upgrade the TC. Something in the 2400-2800 stall would keep it streetable with the 3.23 rear. At that point you could consider a slight upgrade mod to your tranny, such as a Transgo kit. You don't need to go crazy with it, you aren't street racing quarter miles, but you'll notice a difference with what you're modifying.

Back to the TC, I would suggest rebuilding yours rather than buying a TCI, B&M, etc. You may have to look in your area for a tranny guy to give you a TC rebuilder suggestion or maybe some of the guys on this site will recommend one. Just my 2 cents.

Why do you prefer TC rebuilding instead of buying a replacement? I've seen that Hughes Performance makes some nice TC's for decent prices. A 2000-2400 stall converter for example.

We don't have a lot of automatic transmission shops in The Netherlands (Most cars here are stick shift or super modern automatics like DSG's etc). And would you be able to change the stall speed by bringing the TC to a rebuilder?

I've noticed that there are tons of shift kits available. How do I know which one to pick. You've suggested transgo (the TF-2 kit??). But you also have kits from different vendors. Any pros or cons? Is it doable to DIY install a shiftkit?

Do I have to keep stall speed in mind since I currenly have 2.76's in the back with 28" tall tyres? Our speed limit is reduced to a mere 60mph since two months. So not a lot of speed on the highways (and I'll be mainly driving on 50mph roads with the chrysler)

Too high stall speed with 2.76's burns the transmission right?

I forgot to add, thanks for the reminder. With what Dulcich said also was with that change, you can still use/keep the stock converter. Good Luck

Thanks!

One more thing I think no one has mentioned: If you go with a cam with excessive overlap (too much rumpity rump), you will pull less vacuum, and that will negatively affect power brake performance.

Good point. I've head that before. I will keep this in mind

Light stall nothing agressive. I think 2250-2500 if I can remember..but in a big heavy car feels like stock.
However,I added the part throttle 3-2 kickdown to my trans and a shift kit. Very efficient and works very well with the torque curve from the motor. This mod alone even with stock convertor is a huge improvement.
Where I do a ton of highway driving I am running 2.94 gears poached out of a 66 318 Satellite. Not much difference between that and 3.23 gears when running a 2357015 tire. Keeps the revs down on the highway by 500 RPM vs the 3.23's.

To answer another question the 268 cam is the largest to work with stock convertor.
I have power brakes and my vacuum runs between 15-17 inches. The booster needs minimum of 9-10 inches of vacuum.
But 12 and up is where I like to be.
Hope this helps

I've noticed that Hughes performance has a nice 2000-2400 stall converter for a TF727. Might send them a message to get their opinion. Any idea what the stock stall is in our newport?

Which shiftkit did you use. There are a lot of them. And is it hard to install a shiftkit?

So I'm either buying a 268H cam on the cheap to keep the same valvetrain, torque converter etc.
Or I'm buying a bigger cam, possibly springs/lifters? and different converter which adds quite a bit to the total cost?

How big is driveability difference of swapping the stock TC to a 2000-2400 stall TC?

727 3-2 Kick Down Module (1966-69) - A&A Transmissions
Run this if you have the original trans

I've bought this "Part-throttle" kit from Pat Blais

That shop is local to me

Which shop?

 

[jct]

A&A transmission

 

[Metalmarty]

A&A transmission

Whups, missed that
Everything is far away from me unfortunately.
And shipping costs overseas are killing!

 

[cbarge]

All suggestions made are great.
No matter which "combo" MetalMarty chooses,one important thing needs to be addressed for all of it to work-----ignition timing.
A good recurve in the distributor where the goal is the most advanced timing at idle and all in full advance comes in at 2000 and stays there.
With the mods being done,the stock timing specs in the FSM no longer applies.
Whether a points distributor or electronic ignition, adding curve plates or welding the advance slots makes a huge difference.
Stock 2bbl 383 has 5BTC. My car runs at 12 BTC with 36 degrees all in at 2500--which iss where theflash of the TC is and my cruising speed is on the highway!!!! You follow me now?
Hope this helps.

 

[Metalmarty]

All suggestions made are great.
No matter which "combo" MetalMarty chooses,one important thing needs to be addressed for all of it to work-----ignition timing.
A good recurve in the distributor where the goal is the most advanced timing at idle and all in full advance comes in at 2000 and stays there.
With the mods being done,the stock timing specs in the FSM no longer applies.
Whether a points distributor or electronic ignition, adding curve plates or welding the advance slots makes a huge difference.
Stock 2bbl 383 has 5BTC. My car runs at 12 BTC with 36 degrees all in at 2500--which iss where theflash of the TC is and my cruising speed is on the highway!!!! You follow me now?
Hope this helps.

Ignition timing is a good point. That's really an item that can make or break driveability...
I've had a lot of issues with a bad ignition system on my 1.9L beetle engine, so I unfortunately know what headaches this can cause...
The wiring and ignition in my Newport is sketchy at best, so I'm redoing everything.

I've got a new ignition system from Rick Ehrenberg (Distributor, ECU, resistor, wiring, leads, coil with a NOS mopar tan cap).
His systems seem to have a lot of positive reviews.
Together with the other options I will try to run it with high advance on idle with a fast rampup.

I've also completely disassembled my Edelbrock 600CFM carb. All the parts are currently cleaned with an Ultrasonic cleaner.
This will be rebuild with new gaskets, rubbers etc.

So my Carb and ignition should be perfect to start with.


One more question that's bothering me.
How well will a 600CFM carb hold up when swapping camshaft, torque converter etc in a refreshed engine (new bearings, rings, gaskets)
This should enable the 383 to have a decent bump in power in my opinion.

Is a 600CFM carb enough when simply swapping to a 268H camp with stock TC etc.

And is a 600CFM carb big enough when swapping for a bigger cam than the 268H with a 2000-2400rpm TC etc?

 

[Ripinator]

. . . .One more question that's bothering me.
How well will a 600CFM carb hold up when swapping camshaft, torque converter etc in a refreshed engine (new bearings, rings, gaskets)
This should enable the 383 to have a decent bump in power in my opinion.

Is a 600CFM carb enough when simply swapping to a 268H camp with stock TC etc.

And is a 600CFM carb big enough when swapping for a bigger cam than the 268H with a 2000-2400rpm TC etc?

Yes. In '66 both the 383 HP and the 440 TNT used the same 600 CFM AFB carburetor. Your engine is later, but I don't think it makes much - if any - difference.

 

[cbarge]

Your carb will do just fine.
With the mods and dual exhaust you may have to re-jet and swap in different metering rods,not a big deal.

The 66 300 383 is running a 600 Eddy,BTW and we ended up changing the jets and rods to match the dual exhaust and recurve in the timing. Great throttle response and 18 MPG with 2.76 gears!!

 

[marty koirtyohann]

Hi all,

More questions!
I've got a '68 Newport.
It still has the original 383 with 9.2:1 compression in it with a TF727 behind it.
The intake was swapped by the previous owner with a Edelbrock DP4B aluminium intake.
The current carburetor is a Edelbrock 1406 600CFM 4 barrel carb.
Points ignition was swapped with Mopar electronic ignition.

Engine is stock apart from those changes (Stock block, pistons, heads etc).
It has the stock log manifolds going to a single pipe going to the back.
I'm taking the 383 out of the car in the upcoming months to refresh bearings, rings, seals, gaskets etc.

It is worth it to spend an extra 200usd or so for another camshaft?
Or won't that make a big difference with stock heads, stock exhaust and 600CFM carb.
(I might swap to dual exhaust sometime later on)

If so, what camshaft do I want? (out of the 100s available)
I like an engine with a lot of torque and I like some rough idling (not too much)

I've also read some articles about special Mopar camshafts that make use of the big lifters (steeper cam lobes). It is worth buying this?

its yur car do as u like'

 

[Profmopar]

Hello there from Downunder.
It is well known amongst Mopar guys who spent entire weekends under the hood that the Mopar recommendations re camshaft streetability are way too conservative. The old graph of lift vs displacement seemed to recommend lifts around 0.01" too low.
For your combo, as it stands, you'll struggle to beat one of the street-aimed purple hydraulics (you'll love P4452993AE with 0.474" lift both lobes, total duration 280, centreline 110). Can work with stock valvesprings up to 5000rpm, but stronger ones preferred (the correct Mopar springs are still available if you search).
If you're gonna change to 3.23s, go the "Street Hemi" cam (P4120235AE - 0.484" lift both lobes; 284/284; CL 108). Now you do need the right valvesprings, but the TC can remain stock. However, if you fit a looser TC that will stall a few hundred rpm over stock, you'll need new tires every 2nd week.
Your 600cfm Edelbrock will be fine, but a 383 with the Street Hemi stick, looser convertor and 3.23s will come alive with 650-700cfm Holley double pumper (don't listen to the goody goodies here, that carb with your intake manifold will shred anything you put on the rear wheels, and at all sections of your rev range that your Edelbrock's secondary system isn't fully open, you'll be 10-15hp ahead.
Now, I know there'll be naysayers to all of this, but wait till you hear 'em when I mention the next option: P4120659AE - mechanical cam, 0.528" lift both lobes, 284/284, with CL112. You'll need an adjustable valvetrain, the right springs, the loose convertor and 3.23s will be worthwhile. You'll be amazed how streetable this cam really is, and you'll only need to adjust your valvelash (pretty easy to do if you follow the Mopar book) every 1-2 oil changes (and it's fun.....you'll have entered a wider world of know-how).
All the best, mate!

Oh, I should have discussed manifold vacuum, idle quality. and exhaust.
With the two hydraulic purple cams I mention, manifold vacuum at idle will be at least 14" with the "474", and around 12-13" with the street Hemi grind - good enough to run your brakes. These numbers will improve (be higher) with a better exhaust system. Distributor vacuum advance will function fine since the vacuum at rpm above idle will be essentially the same as stock. The "528" mechanical would be similar to the street Hemi, but I have never actually measured it because vehicles with that cam typically run non-boosted brakes, but a '69 Charger I once saw ran that cam in a 440 and the headlights still opened.
Regarding idle quality, the 474 will be almost stock with a slight "cammy" quality. The Street Hemi and the 528 will be unequivocally noticeable (and fantastic in a 383).
Re exhaust: The stock manifolds are fine with all three combos; the real benefit will come via a good straight 2.5" dual with H-crossover, and suitable mufflers. Headers will improve things above 3000-3500rpm, but not as much as the swap from single to dual pipes. If you improve or change the heads, then the headers will shine.
Hope that helps.

 

[Metalmarty]

@Profmopar Thanks for the detailed information.
I will keep that in mind!

I've also talked to Hughes Engines with my specifications.
They've recommended two camshafts for my use with stock or 2400 converter and 3.23 gears.

The 383 low deck whiplash. Interesting cam but I'm not sure if I find the idling too extreme...

And the SEH2832BL-10

The SEH2832BL-10 seems more promising. (It's pretty nice that is has a noticable idle but not as extreme as the whiplash)
I'm not sure how a cam like a SEH2832BL-10 affect power brakes.
And I'm wondering how a SEH2832BL-10 cam hold up with a stock TC or if a 2400TC is a must...

I am planning to change the stock single exhaust to dual 2.5 H exhaust with stock manifolds btw.

Any thoughts on these combo's anyone?

 

[shaun65Polara]

Hi all,

More questions!
I've got a '68 Newport.
It still has the original 383 with 9.2:1 compression in it with a TF727 behind it.
The intake was swapped by the previous owner with a Edelbrock DP4B aluminium intake.
The current carburetor is a Edelbrock 1406 600CFM 4 barrel carb.
Points ignition was swapped with Mopar electronic ignition.

Engine is stock apart from those changes (Stock block, pistons, heads etc).
It has the stock log manifolds going to a single pipe going to the back.
I'm taking the 383 out of the car in the upcoming months to refresh bearings, rings, seals, gaskets etc.

It is worth it to spend an extra 200usd or so for another camshaft?
Or won't that make a big difference with stock heads, stock exhaust and 600CFM carb.
(I might swap to dual exhaust sometime later on)

If so, what camshaft do I want? (out of the 100s available)
I like an engine with a lot of torque and I like some rough idling (not too much)

I've also read some articles about special Mopar camshafts that make use of the big lifters (steeper cam lobes). It is worth buying this?

are you still open for suggestions ?
i have a 65 Polara/383/9.2-1 and just recently fired up my complete engine rebuild.
after lots of research about a year & a half ago...matching 383 commando specs as close as i could find, i went with a Howards racing cam with new Lifters & new TrickFlow push rods slightly different length vs OEM.
its runs really good, very responsive power and a sweet rumble with headers (TTI Style long tube), 2.5" Y pipe into 3" exhaust,
3" stainless magnaflow and 3" tail pipe.

if you're interested, i can get the info & send it to you perhaps this weekend. im currently in my big rig & away from my ride.

 

[shaun65Polara]

 

[shaun65Polara]

Quick Fuel 600
dual plane low rise intake
dual fuel pumps (mech+elec)
AmericanVolt radiator fan
MSD StreetFire w/Blaster2,
using factory dist
dual batteries & aux. fuse panel

 

[stubs300]

View attachment 381848 View attachment 381849

Jesus, what a abomination! Are you actually proud of that?

 

[shaun65Polara]

Jesus, what a abomination! Are you actually proud of that?

you can bet on it stubs
your "shock" rolls off of me like water on a ducks back.
ever heard the expression...it's all pink on the inside ? know the meaning ?
are you a pinkaphobic **** ?

 

[stubs300]

you can bet on it stubs
your "shock" rolls off of me like water on a ducks back.
ever heard the expression...it's all pink on the inside ? know the meaning ?
are you a pinkaphobic **** ?

I'm talkin about the whole F-ing car, not just the underhood!!