Pontiac's SD 455

[1969z280]

I want to own a Super Duty. I keep waiting for the prices to go down and they keep going the wrong way. Check out the Mecum Auction website. There are a number of SD, HO and RA IV cars coming. It looks like Pontiac heaven to me. This particular 74 looks to be a great car and a Survivor but, at that price hopefully it was never rust-proofed or under-coated. I'd like to see the red oxide. JMO, Ed

[L78steve]

This is correct the early test cars got the 041 spec. cams installed. All were supposed to get that cam but emissions nixed it for the 744 spec. cam instead,which is still no slouch.The board on the shaker and the crossflow muffler system killed the performance even more,I'm sure the test cars had this opened up. The quad air valve would never fully open in stock form.[ QUOTE ]
I think I read somewhere that the very early road test SD cars were ringers with a different cam. They were running mid 13s when anything else in '73-'74 couldn't get out of its own way. It seems that even the production ones ran pretty well. In the sixties, Pontiac wasn't above a little creative advertising as in the Ferrari-GTO road test comparison so nothing surprises me there. In '68, I had a warmed over RA 400 Firebird, later a '69 GTO, and more recently a '72 Lemans Sport with a warmed over '70 455. These can be mild mannered, smooth as glass to drive and still run 12s with very little work done to them. Not bad for a basic design from the '50s. Those 454 Firebirds were built here in Canada where they built the 302 Firebirds that Titus raced in the TransAm series in the late '60s.

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[StealthBird]

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I think I read somewhere that the very early road test SD cars were ringers with a different cam.

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The original road test cars were not ringers, they were pre-production models that used the RAIV cam. This was the intended setup for the SD-455. The SD-455 story is fascinating, and a tribute to how grit and determination by a few engineers allowed these cars to be built.

The pre-production SD-455 Trans Am's were built with the RAIV cam, and they passed the EPA emissions test. But the EPA discovered that Pontiac engineers rigged the EGR valve to close after approximately 50 seconds, which just happened to be a few seconds after the standard EPA emissions test was complete. The government was not amused, and they failed to certify the SD-455 for production. Pontiac then had to go back and re-do the setup, elminating the RAIV cam, assigning a new casting number to the intake manifold, and get the whole thing re-certified by the EPA. This is what caused the SD-455 introduction to be delayed, so these cars did not appear until very late in the 1973 model year. Also, because the certification process was so lengthy, and anything from a simple air cleaner change to hood change had to be re-certified, Pontiac decided to build the Formula SD-455 cars with the Trans Am hood, which had already passed the EPA tests (that's the reason the Formula SD-455 cars did not come with the Formula twin-scooped fiberglass hoods).

But in the meantime, the pre-production SD-455 Trans Am's made the rounds in auto magazines, and ripped off mid-high 13 second blasts completely stock (with the exception of an open hood scoop). Amazing performance for an engine with 8 to 1 compression, in a car weighing 3800 lbs, with a steel intake manifold, 3.42 gears, restrictive exhaust, an auto trans, and stock tires.

But when Pontiac had to remove the RAIV cam and put in their boiler plate special .408 lift cam, the cars slowed to around 14 seconds flat in the 1/4 mile. Still amazing performance considering all the other handicaps mentioned above. No cars were delivered with the RAIV cam. The SD-455 engines were quite special, and they weren't simply parts thrown onto a standard 455 engine. The SD-455 used a special block, connecting rods, distributor, carb, intake, heads, and camshaft.

[1970Bluel78]

How about a 1973 GTO with the SD-455 ?? Cars Mag, car of the year. I was told 3 mules were made but the car never saw production. Too bad

[Xplantdad]

I'd rather have a Formula 455 SD...One of CHarley's friends had one...it was blue!

[markjohnson]

I absolutely LOVE the Formula SD455 cars!

[1969z280]

Check this one out:

Mecum 1973 SD Formula

[StealthBird]

Another oddity : The 1973 SD-455 GTO was that the SD-455 engine was scheduled for the Lemans, GTO, and Grand Am ONLY, not available in any other Pontiac. Pontiac sent a 73 SD-455 GTO to CARS Magazine, they proclaimed it "Performance Car Of The Year", but by the time the issue hit the newsstands, Pontiac had already notified their dealers that the SD-455 would not be available in ANY A-body, and all of the engines were going into the F-body Formulas and Trans Am's (Pontiac also canceled the availability of the 1973 GTO/Grand Am Ram Air setup, a system that supposed to be exclusive to the SD-455 engine. A few SD-455 A-Body Ram Air setups were later thrown into the parts bins, and about a dozen were sold).

By the way, people always ask about the difference between the 1973 and 1974 SD-455's, as the 1973 was rated at 310 hp, the 1974 was rated at 290 hp. In reality, they were all 290 hp, but press releases and promotional material had already been released with the 310 hp rating from when the car was supposed to receive the RAIV cam. The 1973 and 1974 engines are identical.

Pontiac Engineers produced over 500hp on the dyno using headers and a RAIV valvetrain setup, and the production engine produced around 350 NET hp, and over 400 NET hp once the exhaust was removed, which places this engine on the same level as the greatest powerplants of the 1962-1970 era. Amazing considering the lousy EGR steel intake manifold, pathetic 8:1 compression, and .408 lift cam.

[njsteve]

[/ QUOTE ]Steve I hear ya but you and everyone else here is forgetting the fact this is a true survivor car with 16 thousand miles! Any 71-72 T/A with 16k on it would be in the 80-90 range also and this car id well optioned with the very rare cloth inserts on the seats which I believe only a handful were built. I think if it was a 73 T/A with these miles the owner would be asking 130-140 for it.

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Original low mileage is pure gold. But I'd still drive it with the low miles - they need the exercise/maintenance.

I think the reason the 74 market is soft is that it just isn't an attractive looking front end with the 5-mph bumper look and the slant nose. The 70-73 styling is so much nicer (and this comes from a guy with a '75 bird that my Grandmother bought new).



The 70-73 is so much hotter looking:

[Steve Shauger]

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SD are unique, but for roughly half the price and just as fast I rather buy a couple of 71-72 TA, 455HO's.

[/ QUOTE ]Steve I hear ya but you and everyone else here is forgetting the fact this is a true survivor car with 16 thousand miles! Any 71-72 T/A with 16k on it would be in the 80-90 range also and this car id well optioned with the very rare cloth inserts on the seats which I believe only a handful were built. I think if it was a 73 T/A with these miles the owner would be asking 130-140 for it. Personally I think its a great car and I like the 74's as much as the 73's.My whole issue with the car is the fact it has to stay in a garage and you cant drive the [censored] out of it like it was built to do. Great car with nice pedigree and colors is JMHO BTW My old 77 Bandit car which is a nothing car but way cool with 10,000 miles on it just sold at auction for over 62,000 so maybe this T/a isnt that high.

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Hey Don, my comment was meant in a general sense. I was not referring to this car. I wasn't questioning the price of this car specifically (I did not even review the ad, and you know I love survivors). My point was that SD's are close to twice the price of a comparable HO. I am going to look at the car ad now. I do have some room ....