[66 Le Mans Cruiser]

Hello. I recently purchased a 1966 Le Mans convertible. Pretty much stock. Has 3 speed and 326. Previous owner put a 2 barrel holley, new air cleaner, sway bar, and dual exhaust.

I am new to the hobby, not very experienced with working on cars but am fairly handy and willing to learn or pay for what I don’t want to learn/do(I am 51 so more strenuous stuff I will pay for)

I love the car. Engine runs great. I don’t really enjoy how sluggish the car is getting going. I have had a few manual cars in the past and this car feels like a dog getting going. First to second and second to third are fine. A few people at cars n coffee as well as reading some posts on here recommended going to a M20 4 speed to get more response from 1st gear.

So is it a direct swap or are there modifications that need to be done(like driveline length, etc)

Is this worth the time/cost? Any other suggestions?

I want the car to be a cruiser. I drive it 5-6 times a week and have no interest in lighting up the tires.

Sorry for the long post and if you made it this far thanks for reading my rambling!

[bdk1976]

Depending on the current first gear in your 3 speed, switching to an m20 may not buy you much (if anything) off the line. What 3 speed are you currently running? What is the ratio of your rear axle?

Something like a super t-10 with a deeper first gear may be more appropriate for your situation, but need more info to make any real suggestions.

[66 Le Mans Cruiser]

Originally Posted by bdk1976

Depending on the current first gear in your 3 speed, switching to an m20 may not buy you much (if anything) off the line. What 3 speed are you currently running? What is the ratio of your rear axle?

Something like a super t-10 with a deeper first gear may be more appropriate for your situation, but need more info to make any real suggestions.

How do I find what transmission it is and what the rear end ratio?

I looked online as the car appears to be stock:

The 1966 Pontiac LeMans featured a standard 3-speed manual transmission, often a column-shifted Dearborn unit, with a heavy-duty floor-mounted 3-speed (frequently paired with the Hurst shifter option) available. These were "all-syncro" units with 1st gear ratios of 2.85:1 for I-6 engines or 2.42:1 for V-8 engines.

Gear Ratios (V-8): 1st: 2.42:1, 2nd: 1.61:1, 3rd: 1:1.

So car has 3 speed on floor with hurst shifter so I assume that is the correct ratio?

[OG68]

First gear ratio
Saginaw three speed is 2.54:1
Muncie M20 is 2.52:1

You're not going to see any improvement there.

[66 Le Mans Cruiser]

Originally Posted by OG68

First gear ratio
Saginaw three speed is 2.54:1
Muncie M20 is 2.52:1

You're not going to see any improvement there.

Is there an alternate upgrade that would help?

Intake/carb?

[OG68]

The Ford Dearborn was optional in the A body with a V8 and floor shift only.
The standard three speed was a Saginaw column shift.
The Dearborn is from the Ford Toploader family and is practically indestructible. Easily identified by the inspection cover on the top of the transmission and the FoMoCo cast on the left side
First gear ratio was 2.42:1

A 3:23 rear axle in your car was standard with the three speed.
3:36 and 3:08 axles were optional with the 2bbl 326.
You can install a set of 3:55 gears to help, but you won't like the 3000 RPM at 60-65 mph
A 4bbl and camshaft change will wake up that little 326.

As a side note, the clutch isn't slipping is it?

[66 Le Mans Cruiser]

Clutch is not slipping but coming from a stop into first there is some chattering if you don’t give it enough gas. Clutch was replaced about a year ago and flywheel was resurfaced. Maybe not a great job on the resurfacing?(or my driving sucks?!?)

[onetirefire]

I swapped from a 3 speed floor shift Saginaw to a 4 speed Saginaw in a 1967 Lemans with an OHC 6.
Bolting in was easy. And Saginaws, even 4 speeds, are usually cheap.
Saginaws have several first gear ratios. I found a 3.11, the ratio that originally came with 67 sixes. It is noticably lower.
Getting a shifter and rods to match up with the console was a finicky business, however. In the end I used period pieces found on ebay.
Price it all out. If you're buying new and want asimple kit with shifter, rods and all, a 5 speed probably starts to come into sight.

[66 Le Mans Cruiser]

Was it worth it to swap?

Car has a rear main seal leak that will be addressed in the not too distant future. Figured while the transmission is out can do a few upgrades.

Thoughts in my head:

New intake/4 barrell carb
Camshaft
4 or 5 speed transmission
New clutch, flywheel, pressure plate

Want to cruise the car not race.
Would like more response from a standstill but don’t need to light the tires up.

I appreciate the advice/thoughts of people with far more experience.

[onetirefire]

It was worth swapping to a 4 speed in my case. But 3 speed manuals are cool too. I would expect a well running stock 326 to easily pull first with a reasonable differential ratio.
You may have to visually id your transmission to verify what you have. Could have been swapped over the years. Same with the differential. Does it still have a 3.23 or did someone put highway gears in it at some point? That would bog you down.
A 326 2bbl should be pretty torquey. I had one years ago. A camshaft "upgrade" likely won't help with more off idle grunt.
Is the engine solid otherwise? Good compression on all cylinders? Strong vacuum at idle, etc.
Also, you mentioned chattering. I'm not an expert, but that is likely an issue unrelated to engine power. Everything put together tight and right?

Originally Posted by 66 Le Mans Cruiser

Was it worth it to swap?

Car has a rear main seal leak that will be addressed in the not too distant future. Figured while the transmission is out can do a few upgrades.

Thoughts in my head:

New intake/4 barrell carb
Camshaft
4 or 5 speed transmission
New clutch, flywheel, pressure plate

Want to cruise the car not race.
Would like more response from a standstill but don’t need to light the tires up.

I appreciate the advice/thoughts of people with far more experience.

[66 Le Mans Cruiser]

Originally Posted by onetirefire

It was worth swapping to a 4 speed in my case. But 3 speed manuals are cool too. I would expect a well running stock 326 to easily pull first with a reasonable differential ratio.
You may have to visually id your transmission to verify what you have. Could have been swapped over the years. Same with the differential. Does it still have a 3.23 or did someone put highway gears in it at some point? That would bog you down.
A 326 2bbl should be pretty torquey. I had one years ago. A camshaft "upgrade" likely won't help with more off idle grunt.
Is the engine solid otherwise? Good compression on all cylinders? Strong vacuum at idle, etc.
Also, you mentioned chattering. I'm not an expert, but that is likely an issue unrelated to engine power. Everything put together tight and right?

Thank you.

Have a mechanic buddy that checked vacuum, compression, timing, etc. All were ok.

Engine is solid. I drove it from San Diego to Vegas when I bought it in July.(drove at night to avoid any overheating).

Only issues I have had have been electrical. Those have been remedied.

Car drives great, holds generally around 170 degrees. Just seems like a dog getting going from a standstill. Maybe my expectations are different from the reality of the car.

[66 Le Mans Cruiser]

Thank you everyone.

Where are the best places to try to locate a saginaw with 3.50 for first gear? I have been looking on here, facebook marketplace, offer up. I see many muncie’s but not many Saginaws.

Been deciding on what my budget for the car is and exactly what I want. For the money I may just buy a second car that has a larger engine and already has a 4 or 5 speed and then have a cruiser(my lemans) and something a little quicker(maybe a firebird).

I have a decent size tax return coming and was thinking of throwing about 5k into this car including labor on things I would not feel comfortable doing myself.

The clutch and flywheel are definitely getting replaced when I have the transmission pulled to take care of the rear main seal leak.
Any further recommendations with that size budget and wanting to keep it a cruiser with a little pep.

Appreciate the advice, some local guys and from reading on here my thoughts to get to where I want:

Performer intake 2156
4 barrell carb- edelbrock 1406
New Clutch
New Flywheel
Potentially transmission swap
I am also redoing some of the interior including carpet and sound deadening but those are already purchased and I will install myself so don’t affect the budget.


What the car is now
1966 Lemans
326
2 barrell
Dual exhaust
Disc upfront
3 speed saginaw
3.08 rear

[buds56]

Depending on your wallet your biggest bang for the buck would be a transmission change to get a lower first gear.

As posted above a Saginaw 4-speed was available with a 3.11: 1 low gear,

I have used many of them in my Pontiacs over the years. Usually you can find one used for $ 3-500 and a new Hurst shifter will run about $700. This is the cheapest way, Same clutch, driveshaft, crossmember.

The best and most expensive ( aprox.4K ) would be a New TKX (which I hope someday to get one), their are several vendors that will sell a kit to make it a bolt in deal.

A four barrel carb is a nice upgrade, but your not going to get much improvement off the line.

And I would not go for a cam change if your just cruising it.

Just my opinion,Good Luck!

[66 Le Mans Cruiser]

Originally Posted by buds56

Depending on your wallet your biggest bang for the buck would be a transmission change to get a lower first gear.

As posted above a Saginaw 4-speed was available with a 3.11: 1 low gear,

I have used many of them in my Pontiacs over the years. Usually you can find one used for $ 3-500 and a new Hurst shifter will run about $700. This is the cheapest way, Same clutch, driveshaft, crossmember.

The best and most expensive ( aprox.4K ) would be a New TKX (which I hope someday to get one), their are several vendors that will sell a kit to make it a bolt in deal.

A four barrel carb is a nice upgrade, but your not going to get much improvement off the line.

And I would not go for a cam change if your just cruising it.

Just my opinion,Good Luck!

Thank you for the ideas.

Would the current Hurst shifter in the car have to be replaced?

[OG68]

Originally Posted by 66 Le Mans Cruiser

Thank you for the ideas.

Would the current Hurst shifter in the car have to be replaced?

Most likely yes. If switching to a four speed the shifter will have to be replaced.

Driveshafts are the same size for all manual transmissions, but you may have to replace the stub shaft If the output splines are different.

Have you ordered the PHS docs yet? They will tell you exactly how your car was built.
But it wouldn't be unusual for a previous owner to switch transmissions or rear axle gearing in the last 60 years.

I have a Dearborn (shown below) in my 68 with 3:55 rear axle. Still very smooth and quiet.

[66 Le Mans Cruiser]

Originally Posted by OG68

Most likely yes. If switching to a four speed the shifter will have to be replaced.

Driveshafts are the same size for all manual transmissions, but you may have to replace the stub shaft If the output splines are different.

Have you ordered the PHS docs yet? They will tell you exactly how your car was built.
But it wouldn't be unusual for a previous owner to switch transmissions or rear axle gearing in the last 60 years.

I have a Dearborn (shown below) in my 68 with 3:55 rear axle. Still very smooth and quiet.

I have not ordered the PHS docs yet, probably should have been my 1st step. Will do today.

Car is getting front discs installed right now, when I get it back home I will take a look at the transmission to see the markings and will post.

So I am a little confused. One person says cam and 4 barrel, another says those will do nothing. Another person says transmission and another says that will not change acceleration from standstill. Another says rear end gear change.

Is this kinda standard that there is no standard? Just trial and error?

Trying to learn as much as I can so every little bit helps, it is one thing to do a google search. But I prefer to ask people with knowledge and experience.

Thank you for your time and advice.

[gtospieg]

You can also look for another 3 speed Saginaw with the 3.50 1st gear. It has the same 3 ring input shaft markings. Then it's a very simple swap...no new shifter needed.

[gtospieg]

B-mans advice is solid. Find a 4-speed Saginaw with a 3.50 1st gear. It's the least expensive option to accomplish your stated use for the car. The Saginaw with 3.50 1st gear is easy to identify, there are 3 rings on the input shaft. While it may be "lighter duty" it will be adequate for your engine combo, especially if you don't beat on it. If you put a Muncie in it you will gain nothing in acceleration (essentially the same 1st gear ratio) unless you also change the rear gear ratio and then you'll wish you had a 5 speed with overdrive. Good luck with your project and keep us updated.

[Mr. G]

I see you are considering a M-20 for your swap. You might want to look at Frank's Pontiac parts under transmissions as he shows a few M-20s in stock and he is located in Southern Cal which would be close enough for you to drive and pick up if you purchased a trans from him. His prices are a little high but saving on shipping may make it a viable option.

[66 Le Mans Cruiser]

Originally Posted by Mr. G

I see you are considering a M-20 for your swap. You might want to look at Frank's Pontiac parts under transmissions as he shows a few M-20s in stock and he is located in Southern Cal which would be close enough for you to drive and pick up if you purchased a trans from him. His prices are a little high but saving on shipping may make it a viable option.

Thanks G I will take a look. There are a couple locally on Facebook market also.