79 TA got a 403 30 over, JM-30-10 Hyd Cam 0.560in /0.576ex , ported heads 207 intakes, forged TRWs, Edelbrock performer intake, Performer 600, MSD AL6. 450+ HP. converted to Muncie M21 with 3:43 gear. love this motor. Bacon strips all day long! So don't bad mouth it till you try it!

I have a '73 with a 455/4 spd. in my garage that I'm getting ready to rebuild and get on the road again after 20 years. Good luck with yours.

I had a 1980 Olds Cutlass that I put a '77 403 in. Got it to run 14.2 in the quarter bone stock with just headers and a 600 Holley. I was impressed.

My grandmother had a 1977 Riviera with the 403. They weren't rockets but I rember grandpa saying it got 22 mpg when we took the car on vacation. Pretty respectful for a big car made in the late 70s.

Really enjoyed the video. Felt like hanging out in a friends garage while talking engines and car history. Have a new subscriber!

In 79 I bought a new 403 T/A black, t-top. At the time I had a 75 T/A 400 auto. Both nice cars not fast but fun to drive. I miss them both. Thanks dad!

People always say the blocks were weak but I never seen one that let loose.

My brother had an '83 Cutlass Diesel that he had swapped a 403 from a Trans Am. It was supposed to have been built, with a Crane hi-performance cam at the least. Man, it was a torque MONSTER!!! With 2.27:1 rear end ratio, it would still break traction, as well as eat motor mounts like 10 year-old with free candy. We ended up putting a heavy chain from the block to the frame to keep it from pulling the one mount apart.

I just picked up a 79 ta 6.6 lt and I'm loving it, only 21 years old and I've had a few Camaros but this firebird I got is just super awesome! Sat since 86 but motor still turns like butter! Keep the updates going! I'll post a video of mine soon!

Olds 403 was probably a bit underrated at 185 hp in the Formula/Trans Am. The Pontiac W72 400 was factory rated at 220 hp but NHRA back then called BS and said that W72 400 was really 260-280 hp.

I have a 79, RE did the engine with a set of #4 heads off a rocket 350, isky cam. roller rockers. and girdled the bottom end. Thing runs fuckin hard n fast, I put a 3.43 rear in it and smoke rubber from 2200 to 4600 and shift at 6200 and its solid for years. Wasn't expensive at all.

0lds 403 is a great motor..big pistons with a short stroke crank.i bored mine 30 over changed pistons to flat tops.installed a joe mondello cam and modified the quadrajet.i surprised alot of mustang 5.0s and HOz28s in the early 80s...had a b/m shift kit with a superholeshot torque converter..

There’s a huge misconception about the Olds 403. GM rated it at 185 Hp, but it cheated. The test was done with less timing. When you set the timing outside GM’s recommended setting, the Olds 403 responded with far more power. Pontiac got away with advertising the W72 400’s Hp at 220 because it was mated with a manual transmission and standard 3:23 gears. I know, as I owned several Trans Am’s in 79. The Olds 403 would walk away from the 400 Pontiac with just a timing reset and 3:23 gears, while still using the stock 3 speed turbo 350. The Olds 403 was also far more bulletproof than the Pontiac 400 as it was prone to rod bearing failure at higher rpms. I will always be a fan of the Pontiac 400, but the truth is, that the Olds 403 was a much better engine.

Because of corporate envy, and corporate politics, Pontiac was the red headed stepchild of GM from1970 and on. GM was all about Chevy; and, if it wasn't for their truck line, GM would have folded. Pontiac should have spun off with John DeLorean, when they had a chance. Then GM finally put it in the grave. It is all water under the bridge now.

403, the biggest small block V8 to exist

I had a 79 ta with the 403. It never boiled over on me but it always ran on the hot side. I later found out the bore was so wide there was no space for coolant flow between the cylinders. I look forward to following your vids.

Had a 79 Buick Park Ave with 403. The oil pump drive driven from the distributor , basically an allen wrench handle, rounded off and ruined the motor . I loved the power of that car

I can't wait to see this all done. Hopefully I will get a chance to see it in person!

Had a 403 in a 77 98 regency. It was a beast! Completely stock raced a 66 caprice 396 that had cam headers and pro trac 60’s. Race was even, he couldn’t believe mine was stock. Looked at my engine and said, he’d of got beat if I would’ve turned over the air cleaner lid. 77’s weren’t choked by the computer carb like 78 and 79.

220 in 79 is respectable

Pontiac does not have a small-block and big-block all V-8s are the same dimension.

GOOD VIDEO. BTW, PONTIAC actually toyed with the idea of a turboed 301 in the 82. If you want to build a stronger 403, some people are grabbing the diesel 350 and boring it out to the 403 size.

Boy, you were high as hell when you made this video, huh?? Lol, good info tho.

I had a 78 trans am 403 at 16 years old back in 1986 i did not treat it well. But it did handle the abuse.

50 lbs? Hey man I enjoy watching your build. I remember a long long time ago we changed some spark plugs on my 1997 Trans Am in your garage. Good times.

A very interesting thing about the Olds 403 is the giant 4.351" bore. It may have the largest bore of any GM engine. I once looked up the bore diameters of other GM engines, and I couldn't find any, even big blocks, even the Cadillac 500, that were as big as the Olds 403 bore. Closest I found was the Buick 455 with 4.31" bore. I measured the weight of the iron intake off my 403 about 7 years ago when I was working on it. It's 51 lbs. I put an Edelbrock intake on it, which weighs 17.5 lbs. I found that the only advantage of the Edelbrock was the weight savings. Otherwise, it ran better with the original iron intake. Better low end. Some day I'll swap it back on.

When I rebuilt my 403 I put a new Napa crank clevit rods and mains stock rods and piston . Double roller timing chain high volum pump comp cams 268h cam had to have the heads machines for double valve spring seals a do not touch coil and an aluminum intake of a 307 olds motor and took time with a deemed tool and opened the ports to match the head ports it threw my 79 ta around very nicely was a real tire smoker and got better fuel mileage then it did stock

the early olds engines had a solid main support, the window main block was for lightening of the block, some of the later year olds engines were actually cast by Pontiac because of the window main blocks snapping off during the warranty period. Pontiac also lightened up their small cube engines including the 301 ci by around 100 lbs. great video btw

Im a Ford guy but i like looking at other odd brands but watching this come apart it has alot of similarities to a Ford Cleveland motor from the valley pan and stamped steel rockers to the fuel pump slot good video

Because the Olds 403 is the best engine ever built. It is strong, fast, reliable, and will run forever. Mine lasted to almost 1 million miles. In a 1978 Buick Riviera the LXXV EDITION. In Black and Silver. I will buy one again. It was beautiful and very fun to drive.

That engine looks good for the age. I remember 200 hp was not bad man how things have changed.

ON the point on the Heads, by the time you do machine work to a set of used heads, you might as well get a set of new aluminum heads from Edelbrock or Speedmaster or Mondello. The price will be the around the same.

I own a 1978 hardtop bonneville sport coupe with a 403, and i own a 4door brougham with the 400(also same year). Me having the best of both worlds,that 403 is no slouch. It has a little more kick than that 400!(and im a pontiac guy).

320ft lb torque @2200 rpm

I put a 403 in my Buick Le Saber(this car was longer than an F150 pickup) and it twisted the frame but man did it go.

The Olds cleaned up better in the emissions department. That is how it was the last carburetor V8 sold by GM in 307 trim through 1987. It was also lighter than the Pontiac 400.

Had a 78 olds 98 with a 403 we stripped for a river car. For the cubic inches the 403 is very light weight.

Love seeing any and all T/A vids. Minor correction: the automatic variant of the 77-79 T/A could in fact come with the Pontiac 400; it's known as the the W72 package (coded WC for the 4-speed, X7 for the automatic). As it happens, my 77 T/A has the W72 package with the 400/auto combo.

Two engines were offered in that era TA. There was the 400 Pontiac and 403 Olds. You can typically tell by the intake cowl. Pontiac said TA 6.6 and Olds was 6.6 Litre. The Olds had slightly lower output, although for its time, it was a decent engine. Today, those HP numbers are laughable. It's like the difference between an Stir-O and Stir +. The Pontiac engine being the Stir-O. The intake was about 60 pounds. My sister had a 79 TA with the 403 Olds engine. I believe that you can source an Edelbrock aluminum intake.

I had a 403 in a 77 Cutlass...It lasted 286,000 and was still running strong when I sold it. flat top pistons and a mild cam and it runs nice. The 2.41 will run like a bear down the highway too...

I removed the intake and Rochester first. Car runs now and way better. Next was headers and pypers exhaust system car has horse power now. Got rid of the 350 turbo transmission, 400 turbo way better no longer destroying the transmission.

The magic in that Olds motor that makes it such a good choice that GM made is going to be it's torque curve, particularly compared to the Pontiac motor. These cars were somewhat quick. You would want to be careful to not over rev it.

Hi I bought the 79 trans am 1986 it was only 66,000 miles on it with the 403 engine I'll tell you man that's the best engine in my opinion with the three speed automatic transmission with the AC I miss that car I crashed it in 1990 the car went total after that I bought the 1981 301 engine it was not the same as 403

Some fact adjustment here needed. I do not believe that is correct about the '77 400. There were two versions of it, the 180hp base engine and the W72 that made 200hp in 1977. The T/A 6.6 version (the W72 200hp version) wasn't available in high-altitude or California, but according to the '77 Pontiac brochure, there is no such footnote for the base 400. The "UR4" option lights you talk about for '80 on the Turbo, didn't come out until mid year. The 403 Olds made 185hp, not 180hp. As others have said, using earlier stock parts on the 403 will wake it up quite a bit. The reason for the Olds engines in the Pontiacs was probably capacity and cost. The Olds engine was probably a higher volume/lower cost than the Pontiac V8, so that is why GM chose to go that way. Also with power being down and the EPA doing their knocking on the door, the higher HP wasn't needed. Nothing wrong with a 403 in its stock form if you know what you've got. Same with a 400/4 speed in '79. Given what you could get at the time, they held the torch.

I had the 79 TA with the Ols engine in college, wish I still had it.

I must be in the twilight zone. Its been 20 minutes till 3 for a long time

neat trick oldtimer taught me before teardown replace oil and run on atf fluid CLEAN+ no sludge first time i did it WOW looked like new after tear down

If you like the small block look for a 1967 olds 330 high compression 4 barrel card with 320 H.P. take the 403 connecting rods and use them in the 330 they will bolt right in wit the 330 fridge crank small chamber heads resize valves shot lean the rods little tricks you can get 7000 R.P.M. 403 had heavier rods than the 330 and 350...

180 HP and about 320 Ft Lbs to get those heavy 70’s era cars moving respectably! I’m guessing 57 lbs for the intake. It’s amazing where we are now with engine tech compared to those days.

This is a great motor it will run for ever its the 70s that hurt this motor.

Wow this is one long lament. Actually looking at the development of the Olds " Rocket " V8 ( read hi compression ) the 403 is a masterpiece. The voids in the crankcase webbing could be reliefs ? I always found the timing chains and valve springs from the factory were weak spots but Olds did it for quiet & durability. Talk to Edelbrock about their head/manifold package. EFI it like the fellas at GMC Co-Op did and run it yer ole motor home ! Short of that talk to Joe Mondello and have him do some custom surgery on the ole ' gurrrl and she'll be strip ready befor ya knows it ! Cheers

Man this is hard to listen too. Whats with the clicking sound after every pause?

I can't remember if it was car and driver or car craft ( Probably C/D) but during their testing of the 79 Turbo T/A they actually had to put the rear wheels in water to smoke the tires. It simply wouldn't spin'em on dry pavement. However, it did give a pretty good kick in the pants getting on the interstate once you had some rpm and turbo buildup. My youngest brother had one. When the blow by became to excessive in the 301T we swapped out a 1969 455 olds in its place. Turned that car into a real monster with 355s in the rear.

I don’t care how much power they get today out of the supercharged engines I will always miss big block naturally aspirated engines.

403 rocket from olds station wagner with 455 heads Holley double pump 650 and sanderson Headers its a beast

Replaced a few 307 's with 403 and run great

It can be a easy 12 second motor no problem. Put some Edelbrock performer RPM heads on it and a port matched intake.

I took one out of a 79 park avenue and put it in my regal. It neck and neck with an 88 iron. It didn’t last long it was really worn out

Low end torque at low rpm, to meet emission standards with low compression, with s*** rear end gear. A friend of mine got the compression ratio up changing pistons. Mild port work on heads, now it's actually it was a pretty stout motor. It's just far too expensive to build a 403 compared to a small block chevy. Most people aren't aware of the 403 is a small block olds, not the same block as a 400 olds from the 60s. The 400 olds had nearly the same bore & stroke, the 403 is large bore, short stroke.. Very cool, look forward to seeing your rebuild.

I hope u can get this trans am back in shape I love the 403 ta regardless if it's an olds engine good luck

I may be putting too much thought into this, but I’m sure it has been researched at some point in the past that crankcase pressure at higher RPM robs horsepower. As we know, an engine is just a big air pump. While the pistons are moving up and down in the cylinders, there are forces on the top of the piston as it completes the Four stroke cycle. The same goes for the bottom of the piston. While the pistons are moving in the cylinders, air that is in the cylinders under the pistons needs to be displaced to a different part of the crankcase. Having those windows in the main webs inherently will reduce air resistance. Considering the RPM range that the 403 operates, pumping losses probably are not that big of a deal. Therefore most likely it is an engineering feature to reduce the weight of the block. Crankcase pressure pumping losses have been taken into account in the past. One solution is to pull a vacuum in the crankcase, resulting in lower pumping losses.

I have the 403 in my 79 cutlass Calais you can’t kill that motor even if you wanted to I take should be at least 60lbs

Was a great engine even bone stock. Had one in my 78 delta 88 2 door. I believe it was 2.73 gears not completely sure was 2 .something anyway with a turbo 350. Took a bit of know how but as long as you knew what you were doing and not baby the gas pedal it would kill the rear tires all day long. Many times getting on the interchange thats a death trap near where I was living with a very short weave lane and heavy traffic constantly mashing the pedal and just as the 4 barrels opened up kick it sideways at 50mph for the next 1/4 mile or so

Great information. Well explained. Thanks. This helps I have a 403 its stuck so I dropped some penetrant on it.

How's that 403? Curious because I too am rebuilding one. Would love to see an update.

It's no surprise outside of Chevy Oldsmobile engines supplied power to many agriculture machinery , RV's , and on and on. The 4a heads just need a boat load of work . The ticket is earlier heads with big valves , bowl work and they will save a bunch of time and money.

Thanks for telling us how much the intake weighs like you said you would...

Did you know if you ordered a towing package from the factory the 403 came with 4 bolt mains? This is a very rare block and i never seen one myself. i built a 403 for my 76 formula and i put a cam and timing chain ,springs and seals kit in it and it is rated at 5 h.p.s more than the pontiac 400. headers and a aluminum intake with a new carb makes my formula burn rubber at will. Found the engine and t-400 transmission in a 79 Buick Rivera with just under 45000 km's for 500.00 bucks canadian. The sun roof was left open when i rained for a few days in southern b.c. and the owner parked it because it smelled like a fish velour wet dog interior. the most rare part it the power steering non air pulley. Do not bend it or you will be paying big bucks for another one.

301 pontiac turbo we got turbo and carb adapter off of them sure made 327 sb run good

This guy is boxed 🍻🍺🥃🍸🍾🍷

And honestly, the whole reason the Olds 403 was even developed, was because the Toronado was still big in 1977 (didn't get downsized until 1979), and the Olds 350 wasn't enough motor to power the 4,600 lbs Toronado, but they couldn't justify keeping the 455 big block around just for 1 model (as the Delta 88 and 98 had been downsized)

I had a 80 trans am 301 turbo.once you got all the emission control crap out of way and put a good carb on. Msd ign forged internals in eng and put 411 gears in rear.you have a tire spining monster that is fun to drive.

I thought the 403 was originally 4.351 bore and a 3.385 stroke,well anyway a friend of mine at Olds back a while said he could get my 403 block and crank nitrided in their ovens for about 1700$,they would have to x-ray them before hand for cracks,well they were cracked,so I stuck with my 350,when I sold that car it had 220,000 miles on it,4 rebuilds in it and still produced 450 whp and 550 pound/feet of torque.

I think the bore size is like 4.35 or so 3.30 stroke would be neat to hear one turning a lot of rpms . Would work great with a stick shift

403 Olds has the biggest pistons ever used by GM in a passenger car

They did it more than once. My 1981 Bonneville has an Oldsmobile 307.

185 hp/320 ft lbs; both net figures. Better than Cadillac or Buick engines. A 403 Trans Am has the best of both Pontiac and Oldsmobile. By the way, I own both a Pontiac and an Oldsmobile. That 403 had a very big bore and a very short stroke.

The way to tell if it had the Pontiac engine was the screaming chickens wings swept onto the fenders.On the the 403 equipped versions the wings never extended beyond the hood.

I had a trans am 1979 black and gold special edition glass tops. It had a 403 olds as I got it in California one of the best cars I ever owned. It was plenty fast enough for me as well as an eye catcher for the time....I totaled it 1981 racing in the rain otherwise no complaints....The next car I got with the insurance money was a 1980 Corvette L82 engine nice looker but the worse car I have ever owned...That engine was a piece of crap it threw a rod 3 years after buying it what a waste.

Haven’t seen a built - I mean really built 403 handle the horsepower levels well. Block is not strong enough to last. Rocket makes a bulletproof olds block for racing. Stock block is fine for street level hp only.

Why all the tears on the 403? Best Bore vs Stroke of any factory engine... ever.

The widow mains suck but I kept mine under 5000 rpm and never had an issue it’s a low end motor build for low end and enjoy

So how much horsepower are you wanting? 500’s?

Pontiac ceased to be a division of GM in 1979. It became a brand of GM in the early 1980's.

Hi, great video! Would like to see more vids about your engine rebuild! What eutectic pistons for the 403 would you recommend?

Good video. Don’t have much good to say about the 301,307 or 403 myself lol.

600 hp on that 403 block, ill say its a bit weak. Get a olds diesel block its has more meat for it sizes.

Tell us if the 403 was drilled for a manual pilot bearing/bushing? Will you see if you can find a pilot bearing that will fit that crank? 😉

about 100lbs. The Olds is a good low-end motor. "No replacement for displacement"

It's simple, Pontiac V8's were no longer allowed to be sold in California after the 1976 model year, and California is the biggest car market in the country

Great video buddy!

Any news about the engine? has it been rebuilt? is it running? what about the machine shop? Thanks

i cant beleave he did it with out swearing i always get at least 1 mfr & 4-8 SOBs

I'm about to buy a 77 buick electra that's supposed to have a 403 motor. What should I look for? As of stamping or does that only matter with 305 and 350s?

50 pounds i know i right. but that intake can flow good numbers . the short coming in first the camshaft then the compression but it will NEVER flow well past 4k with the stock cam.

great video! would you be able to make a video on a 305 tuned port injection?? :-) that would be very helpful

What is the purpose of these U shaped clips on the rocker arms?

Hahahahaha my 79 Trans am with the 403 olds blew away every Pontiac 400 Trans am in the 1/4 it came across. THEY WERE LIMITED EDITIONS WITH DUAL EXHAUST AND SHIFT KIT FROM THE FACTORY AND WAS THE FASTEST CAR FROM THE FACTORY JUST NOT LISTED AS PRODUCTION BECAUSE IT WAS LIMITED TO GET AROUND THE LAW ON EXHAUST AND CATALYTIC CONVERTERS THAT STARTED IN 79

Good torque and would pass emissions.... Had one of these motors in a GMC Motor home - front wheel drive toronado set up

45 pounds easy on the intake. What a boat anchor.