Putting A Five-Speed In A 49-54 Chevy - Street Rodder Magazine

Putting A Five-Speed In A '49-54 Chevy - Transformation

In most regards, '49-54 Chevys were pretty cool cars-and with a few tweaks, they can be even cooler. Few engines sound as good as a six with a split manifold, good shocks and a set of radial tires can do wonders for the handling of a shoebox Chevy and just about any car looks better with the right wheels and a little bit of a rake. It doesn't take much to make these cars into great-looking cruisers, but then looks aren't everything.

1101sr 01 O+49 To 54 Chevrolet Transmission Installation+ Ken and Nick Smith, of Hot Rod Works, found this cream puff '51 Chevy and turned it into a real driver, with the addition of a Chevy S-10 five-speed transmission.

Like many makes of this era, the stock factory gearing found in these cars means the engine is going to be spinning more rpm than is healthy when trying to keep up with contemporary highway traffic. Most '49-54 Chevys with standard transmissions had 3.70 or 4.11:1 rear gears-the later Powerglide-equipped cars had 3.54:1. And while it was once popular to put an automatic rearend in a three-speed-equipped car, what these cars really need is a better gear spread in the transmission-a lower low and an overdrive top cog so taller rear gears can be installed, and one of the easiest means to accomplish that is with a readily available and affordable Chevy S-10 five-speed transmission. Now, before we go any farther, we should explain that the transmission swap shown here also requires replacing the original rearend and enclosed driveline, but rest assured the final result is worth the effort.

The installation shown here was done by Ken and Nick Smith, of the Hot Rod Works in Nampa, Idaho. Known for late-axle and open-drive conversions for early Ford rearends, the adapter and crossmember kit shown here are their first Chevy products, but like everything else they do it's well thoughtout and executed.

1101sr 02 O+49 To 54 Chevrolet Transmission Installation+ Not only is this an easy, affordable swap, the shift lever even comes out in the right spot and that overdrive gear is an engine saver.

Typical of their precision approach, the Hot Rod Works adapter has a lip that registers it precisely in the original bellhousing. The only modification to the transmission is some minor machine work to the front bearing retainer. On some transmissions, the thickness of the front bearing retainer has to be reduced to 0.300 inch (some are already thin enough); all require shortening of the throw-out bearing snout and countersinking of the attachment holes. Once done, all that's needed to button up the trans to the engine is an '82-90 Chevy S-10 clutch disc, a new throw-out bearing, and an original six-cylinder pressure plate.

While it is possible to modify the original transmission mount/crossmember for the swap, Hot Rod Works offers an affordable replacement. Made from round tubing, it will mount the recommended Chevy S-10 five-speed transmission into any '49-54 Chevrolet passenger car, except convertibles. The new crossmember fits above the transmission for increased ground clearance and bolts to the holes for the original holes once the stock piece is removed.

1101sr 03 O+49 To 54 Chevrolet Transmission Installation+ The '49-54 Chevy three-speed transmission wasn't a bad gearbox in its day, but if a rebuild is necessary the cost to freshen it up will likely be more today than swapping to a five-speed-without the benefit of two more gears.

With original retail prices of $150 for the adapter, $190 for the crossmember, and the going prices of S-10 transmissions this has to be one of the most affordable transmission swaps ever. It gives an old Stovebolt the longer legs it needs to keep up with traffic without a strain, which is a great way to make a cool car cooler.