Need some basic direction: c4 vs. T5

Stang66swt

New Member
Jan 8, 2009
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Texas
My '65 vert has a manual 3-speed and I've seen a lot on c4 and T5 stuff. I want to keep the car a stick. I like the idea of an overdrive for longer trips but I get the feeling a C4 might be an easier, less involved, cheaper, and strong option. I'm just getting started so I'm turning to y'all for my first step.

Any info, opinions, facts, criticism will help.
 
you can get away with alot of rear gear on the street with that t5's overdrive. the c4 is good to just pop in drive and go, or if you have a hardcore street/strip car. if its a street driver, t5 all the way. only downside is the low torque handling in stock form
 
If you have 3 speed stick, going to c4 does not make much sense unless you want autoomatic for some reason. Going to t5 will give you smoother acceleration because t5's 1st gear is numerically higher than 3-sp's 1st. Rear gearing 1:3.00 or less, combined with somewhat sporty camshaft (stock too), will cause you won't have enough rpm/torque for 5th until around 90-100 mph
 
there are a couple.

4 speed toploader (more common in later stangs)
4 speed t-10 (more common in early stangs 65ish)
4 speed srod (late 70's overdrive piece o' crap)

Ok, then these are what I should be asking about compared to the T5. No doubt the T5 is a solid replacement and everyone likes it but does it cost more and involve more to do the T5 over a 4 speed toploader
 
any of the transmissions I mentioned will be easier than a t5.

The t5 swap requires some custom parts which will either $ or fabricate.

The 4 speeds will bolt up and use the existing linkage. I don't have experience with 3 speeds so I can't say for sure that the driveshaft will bolt up.

To swap a t5 you either need an adapter plate (early linkage and bell) or late model bell clutch and cable. You will need a crossmember with either setup.

I went from a t10 to a t5 and needed to have my driveshaft shortened. I used a late model bellhousing, clutch and cable. I fabbed the shifter, cable quadrant and crossmember myself.

as for the money

I have about $1200 into my swap.
$450 tranny and hurst shifter
$200 king cobra clutch(new)
$140 billet flywheel(new)
$25 bellhousing
$10 blockplate
$30 adjustable clutch cable(new)
$192 shorten driveshaft and new hd u-joints

The steel I used was scrap so I have no idea what that cost and many of these parts were purchased 5+ years ago.

Smallblock 4 speed toploaders on ebay go from $500 to $1100 so I am not sure the cost differential is that dramatic. It just depends at how patience you are at sourcing parts.
 
A good Toploader alone will very likely cost more than a good T5 and it has no overdrive. Your cruising rpm with the current Toploader 3 speed will be the exact same as with a Toploader 4 speed. The only difference will be another gear in the middle, which does help drivability. A C4 will be the same way. As an example, I have a Toploader 4 with 3.50 gears and 26" tires and my cruise rpm at 60mph is around 3000. I plan on getting either a WC T5 or Tremec 3550(used) in the future.
 
The toploader will take almost anything you can throw at it. It is as bulletproof as any factory item gets. You will spend way more on a 5spd that can handle high levels of torque. A c-4 can be built to handle gobs of torque. Gear vendors makes an overdrive that bolts on, but you will have to shorten your drive shaft and the unit cost$$$$.
 
If the car in question is the '65 convertible Stang66swt mentioned in the Talk forum, then it really doesn't need Toploader strength unless it's destined to be a drag car. Also, since it is a convertible, you would do well to not make any irreversible modifications to it.
 
A good Toploader alone will very likely cost more than a good T5 and it has no overdrive.

no kidding . . .

I am looking for a toploader to face-plate for a race car and junk cores are $400+

t5s (especially the 4 cylinder ones) are a dime a dozen and you can buy a working one for $400.

I had $800-900 in my swap but I built almost everything myself, worked at a mustang shop (discounted parts) and my falcon driveshaft didn't need to be shortened.
 
So the T5 wouldn't really be a perminent mod?

Not if you use the manual bellcrank linkage and spacer plate. The only thing you might need to change would be drilling a hole for the clucth linkage in the firewall. I am not sure if the hole was pre drilled at the factory on auto cars. Either hydraulic or cable would require additional holes to be drilled in the firewall. There might be one cable setup (Ron Morris) that uses the original bellcrank hole but I can't remember.

On a driver quality car I think a manual tranny swap won't affect the car's value either way.
 
Not if you use the manual bellcrank linkage and spacer plate. The only thing you might need to change would be drilling a hole for the clucth linkage in the firewall. I am not sure if the hole was pre drilled at the factory on auto cars. Either hydraulic or cable would require additional holes to be drilled in the firewall. There might be one cable setup (Ron Morris) that uses the original bellcrank hole but I can't remember.

On a driver quality car I think a manual tranny swap won't affect the car's value either way.

Good info. I definately want to keep the car a manual tranny.
 
Good info. I definately want to keep the car a manual tranny.


I forgot you had a 3 speed. I kept thinking you had a c4 from the subject title.

One thing you would need to modify if using spacer plate and bellcrank is the bellhousing. You need to drill some holes in the bell to attach the spacer.

Driveshaft shortening seems be sporadic among conversions. My 67 had a t10 swapped into it at some point in time and it had a solid driveshaft with an 8 inch rear. When I put the drivetrain into my 68 using a 9 inch and t5 the driveshaft needed to be shortened. It could have been the rear or the tranny or both having caused this.
 
I'd have to go for the 5-speed, if for no other reason than because it's overdrive. I'm not one for modernizing these cars too much, bit I am an overdrive fan because of the flexibility it affords you in balancing driveability and mileage. I'm thinking about an AOD swap for my current C4.