I think I have a ’68 Ram Air 400 because the engine code is XS, but the number above it is 0299411, which I can’t find in any of the decoding books. Please help!
Rocky Rotella responds: Bill, code XS was used during the ’68 model year on 400-inch Ram Air A- and F-body applications, as you’re aware. The 0299411 that you’ve located directly above it is actually the engine’s sequential build identifier. Often referred to as Engine Serial Number (ESN) or Motor Unit Number (MUN), it was applied at the engine plant during assembly and has no direct correlation to the vehicle’s actual identification number (VIN).
To properly identify your block, look for number 9792506 cast into the ledge just behind the No. 8 cylinder. The date the block was cast is located near the distributor hole. The block’s VIN stamp can be found lower on the front, most likely near the timing cover. It consists of nine characters and will start with 28 (2-Pontiac, 8-1968 model year). The characters that follow will be the assembly-plant identifier, and then the last six digits of the actual VIN.
If you desire, for a fee you can then take that partial VIN to PHS Automotive Services (www.phs-online.com) to learn more about the type of vehicle the block was originally installed in.
I feel your best move may be to save up a few more dollars and purchase a new T56 Magnum (TR-6060), which is essentially a heavily-fortified replacement for the T56
Work Two More Shifts
I have had a ’68 Firebird for close to 13 years. I just rebuilt a ’73 Pontiac 400 for it, with mildly ported Edelbrock heads, a Comp Cams roller cam, and forged rods and pistons. This is backed by a Muncie M20 and 8.5-inch 10-bolt stuffed with a 3.73 Posi.
I want to drive more on the highway and this has led me to wanting a Tremec T56 six-speed manual. I have done an extensive search and posted in a couple of places with no luck. I have to keep this on a budget, so I’ve been looking at the T56 LT version from ’93-’97 as they are cheaper than the newer ones. How can I keep this from being way too expensive and still dependable?
Rocky Rotella responds: Josh, having installed a TKO-600 five-speed manual trans in my ’76 Trans Am, I certainly understand your desire to install a modern overdriven manual in place of your vintage four-speed. You will find that it increases your Pontiac’s versatility, and you’ll feel much more comfortable cruising with traffic at normal highway speeds. It’s a modification that most four-speed owners would likely appreciate, but a transmission swap isn’t in everyone’s budget, and depending upon the chassis, it can require additional -- and sometimes permanent -- modifications.
I own an ’01 Trans Am equipped with a six-speed manual transmission that I purchased new. The T56’s tight shifting gate, excellent gear spacing with two overdriven gears, overall smooth operation, and sound durability make it a logical choice for hobbyists seeking to retrofit their vintage vehicles. I have never installed a T56 into an older vehicle, but I know that those installed behind LS-powered Firebirds and GTOs (or the Dodge Viper) are more desirable than those originally backing an LT1. There are a few reasons for this.
The LT1-spec T56s built in ’93-’97 were rated at a lower torque capacity, so they aren’t quite as durable as the Viper or LS-spec units. Additionally, the LT1 used a pull-style clutch that’s unique to that engine. It’s a cumbersome design that required a specific bell housing and shorter input shaft when compared to the LS-type trans. If you were attempting to install the LT1-spec T56 behind another Chevy mill, the task would likely be easier but still isn’t a direct swap. Attempting to install one behind a Pontiac V-8 is definitely more challenging! You might now have a better understanding as to why the LT1-spec T56s aren’t as desirable as others and are usually less costly to purchase on the used market.
Installing a T56 originally installed in a ’98-’02 Firebird or ’04-’06 GTO onto a Pontiac block is as easy as bolting on a flange adapter that’s located between the stock bell and transmission. Another alternative is a new steel bell from Quicktime that bolts directly to a Pontiac block and allows the use of a stock-type clutch.
Paying a bit more for an LS-spec T56 may put you money ahead when considering the modifications required to make an LT1-spec T56 the equivalent. Such components are available from various transmission-specialty shops, and I checked with American Powertrain (www.americanpowertrain.com) to verify accuracy and availability.
One point noted when gathering information from American Powertrain on the subject is that the shifter location found on any T56 -- whether LT1-, LS-, or Viper-spec -- is nowhere near that of your Firebird’s original. It will be relocated rearward by a few inches and it’s highly unlikely that you’ll be able to reuse your front console, if so equipped. Since the T56 uses an electronic speedometer, making your mechanically driven speedometer operational will be another challenge. Installation will also require modifying, fabricating, or purchasing a crossmember and driveshaft. American Powertrain can help with any of these needs and supply any necessary components.
When considering everything involved, I think it’s pretty safe to say that a low-buck approach will be a stretch. You’re probably looking at $1,600 to $1,800 for a used LS-spec T56, which will then present the challenges mentioned above. I feel your best move may be to save up a few more dollars and purchase a new T56 Magnum (TR-6060), which is essentially a heavily-fortified replacement for the T56. It fits and installs similarly, but is much more user friendly for most any chassis. It accepts different shifter positions and is fitted with a mechanical speed-ometer drive. A brand-new unit starts out at about $1,000 more than a used LS-spec T56.
American Powertrain can provide you a quote for the trans, flange adapter, and most any other component required for an easy install into your Firebird.
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