[1973T/A]

I have a NOS 403 olds intake that is factory dealer add on and i was just curious what there worth might consider selling.

Thanks
Pax

[DEEZPAZ]

Are you considering selling these? If so, how much and do you have pix? Whats the difference between the high performance and regular?

[BVR421]

those were the famous nashcar 403 manifolds, usually an extra 100hp

I have one of the rare nos olds logo air freshener that was a giveaway when you bought that special dealer only manifold.
Ill take a $100 for the olds air freshener.

[DEEZPAZ]

Would you get the same hp if you put headers on the car??

That seems a little steep for an air freshner but I see how its a rare item and may fetch that much!!

[DennisG.]

Originally Posted by 1973T/A

I have a NOS 403 olds intake that is factory dealer add on and i was just curious what there worth might consider selling.

Thanks
Pax

Whats the casting number and do you have any pics ?

[1973T/A]

i put it on my 403 but im thinking im goona take it off again. Possibly sell it. i painted in which was prbly dumb but it will come off.

[1973T/A]

the numbers are 22504068
and cfd9

[Brian Baker]

An extra 100-HP from just an intake manifold? I don't think so (LOL). Interesting piece though, I'd like to hear more about it.

I got an extra 250-HP out of a 403 once. Know what I did? Yanked that anemic POS out of my 79 T/A and dropped a 455 Pontiac in its place.

[Aus78Formula]

An A4 aluminium intake off early 80's 307 Olds, 403 had come and gone before these existed. Benefits over stock #16 403 intake? , weight savings only. Not really worth anything interesting. Could be ported to flow ok and had the larger ports than the A5 intakes but in stock form were not as good as the #16 other than the weight advantage.

Extra 100hp? I think if you bolted it on without mods you would notice nothing and possibly lose some not that you would notice, also has ridged/hatched floor of chambers to help fuel mixing which actually hurt flow compared to plain.

For interest, this was the intake that Edelbrock based their Performer on, although improved flow and got rid of the hatchings etc, and as you know it usually isn't claimed to be much more than weight savings, but easier to port to flow well.

So is it of use, it isn't bad and can be made to work, is it worth heaps, nah, maybe someone with an 80's Hurst? Looks good in silver, better than corroded and stained aluminium!

And don't forget, when the Pontiac 455 was finally pulled out of production it was only coughing up 200hp! That's only 10-15hp more than the 403 for an extra 50 cubes. Had the 403 been born 6-7 years earlier with decent heads/compression and stronger bottom end it wouldn't be such an easy decision which engine to take! I like the novelty and challenge of having an engine that isn't a SBC and can also perform like others claim it can't

[1973T/A]

Ya punched in the numbers and it came back as 307 intake... Not happy. I bought it when i was just getting into the hobby didn't really know what i was looking at.. The guy told me strait up thats what it was. Now i know to question this guy next time.. I was building this 403 and i thought it would be neat to have a factory high performance intake on it. But i guess it happens. Sorry bout that guys. Another thing 100 extra horse out of an intake?

[goatwgn]

Originally Posted by Aus78Formula

An A4 aluminium intake off early 80's 307 Olds, 403 had come and gone before these existed. Benefits over stock #16 403 intake? , weight savings only. Not really worth anything interesting. Could be ported to flow ok and had the larger ports than the A5 intakes but in stock form were not as good as the #16 other than the weight advantage.

Extra 100hp? I think if you bolted it on without mods you would notice nothing and possibly lose some not that you would notice, also has ridged/hatched floor of chambers to help fuel mixing which actually hurt flow compared to plain.

For interest, this was the intake that Edelbrock based their Performer on, although improved flow and got rid of the hatchings etc, and as you know it usually isn't claimed to be much more than weight savings, but easier to port to flow well.

So is it of use, it isn't bad and can be made to work, is it worth heaps, nah, maybe someone with an 80's Hurst? Looks good in silver, better than corroded and stained aluminium!

And don't forget, when the Pontiac 455 was finally pulled out of production it was only coughing up 200hp! That's only 10-15hp more than the 403 for an extra 50 cubes. Had the 403 been born 6-7 years earlier with decent heads/compression and stronger bottom end it wouldn't be such an easy decision which engine to take! I like the novelty and challenge of having an engine that isn't a SBC and can also perform like others claim it can't

Makes me wonder what "could have been" as well. The large small block 403 olds was developed as a replacement for the 455 Olds that had been available in the 6-800 lb heavier 76 full sized cars. The 403 ran about as good in the lighter 77-79 big cars as the 455 did in the earlier ones (actually a little better in some cases). If the 403 had been out say around 1968, it would have had the solid webbing of the 350sbo, and better flowing heads such as the ones on the 68 ramrod 350, higher compression, ram air and 3.90 gears. With the large bore and short stroke of these engines, they would have been a real screamer. I have seen several 350 W31 Cutlasses with the 3.90 gear take an Olds 455. A 403 built to the same specs with possibly even bbo cylinder heads and a special high port intake would have worked real well with that gearing IMO.

[BOPcollector]

That intake is definitely a stock Olds part. Some 403 and 307 engines came with factory aluminium intakes. More so for the 307. There have been rumours for years about solid mains in the early 403 production, but none have ever been seen as far as I know. The bore size makes it almost impossible for solid mains. It would be a very thin wall below the cylinder bore, but I guess anything would be better than air. The siamesed cylinder bore of a 403 is a larger diameter than a 455 Olds. The 403 was a good engine for the time. It made decent torque at a low RPM. 320 lbs ft @ 2400 revs and only 200 hp. Worked well with 2.41 gears in a '77 up fullsize. Half decent acceleration, passing power and decent gas mileage. 20 mpg or so on the open road. GM did not have a 4 speed overdrive yet, so a 2.41 gears and low rpm torque was the ticket.

[1973T/A]

My friend of mine is a big olds guy and he swears up and down the did make a solid webbing 403 he said they were in the big cars like caddys and the motor homes they were in.

[Aus78Formula]

Big Olds guys can be wrong then, you're now one up on him for knowing better

[1973T/A]

So I take it they never made one?

[Aus78Formula]

No one has ever found one, that's the point. And plenty have looked. Performance packages, towing options, large cars, X on side, casting number ...whatever, they have all been looked out and found to be the same. And it would be pointless without uprated power and output levels to where the windowed mains can be an issue, and there was about 5-10hp between the 403 models based on tuning and carb setup etc.

[1973T/A]

http://tech.classicoldsmobile.com/40.shtml

Found this on classic olds

[Aus78Formula]

It's a Mondello joke, even they never had one to prove they existed, and the numbers and vehicles they mention...all the same, even late 76 builds.

[BVR421]

Originally Posted by 1973T/A

My friend of mine is a big olds guy and he swears up and down the did make a solid webbing 403 he said they were in the big cars like caddys and the motor homes they were in.

403s never in Cadillacs, 350 sbo in some Sevilles and Eldorados (FWD cars)
GM motor homes got Toronado FWD and 455. NO 403.

[1973T/A]

Hmmmmm... I was pretty sure there was but i could be wrong