[grivera]

Interesting video - gotta go to about 1/3 into it for his reasoning: https://m.youtube.com/watch?v=Kgd3pJlM_ps

[chuckies76ta]

Thanks for posting. Very interesting. I like the skit at the end of video.. lol

[Half-Inch Stud]

UT calls the MFG constraint (of cast steel rods) a "design flaw" whereas it was a corporate edict to be the performance constraint.

Think about it: Chevy being the cheapest vehicle line gets forged cranks & rods, whereas PMD leading the 1960s SALES RECORDS was constrained to cast crank & rods.

Was no wonder to me back in the 80s to why every production V8 was "design-limited" to 150% of stock HP, by virtue of block thinning in key zones, or oil delivery.

Bad enough that all the heads had "exhaust crossover" which super-heated the headgasket zone, and carb. Seemed benign when in put-put but Overkill when getting along with extended foot pedal.

Overall, the BOP 10-bolt rear constraint is a laugh, whereas GM's 12- bolt was top-shelf. Dana60 being just right. Nowadays the rear are much more stout for less TQ and HP in SUVs, flyweight mustangs, and the 90s Towncars, Continentals, etc.

Is why we make the modifications.

[track73]

To me Chevrolet’s lighter rotating assembly and light weight block plus their cylinder head design were the reason people raced them instead of Pontiacs on the short tracks.. And I’ve been a Pontiac fan since Fireball Roberts won races in the 60’s. However, I’ve owned Pontiacs but raced Chevies

[PAUL K]

Pontiac started out with forged rods and crankshafts. They were replaced with stronger cast rods and crankshafts for all the non-performance engines. Pontiac's cast crank have held up in builds producing over 1,000 horsepower. I haven't watched the video yet but from the comments above it seems like the cast crank and rod situation may be mentioned.

[mgarblik]

Watched the video. Always loved the way Tony pronounces Pon T ac. I agree with some of his points, but not his conclusion. Agree EVERY domestic engine design of the era, or any era, has some weak points, he calls design flaws. My list could be a mile long, but lets talk about Pontiacs. Pontiac connecting rods are a weak link, yes. Design flaw?, no. If they were a design flaw, they would be failing in "normal use and service", which they didn't. A n example of a "design flaw" would be a Takata air bag. It blows up and kills you in normal use and service. A Pontiac cast rod is just fine to 5800 RPM's in a 400 or 5500 RPM's in a 428-455 indefinitely at 500 HP. But at high HP levels, when something fails, it will be the connecting rods, I agree with that. Is that the reason the aftermarket abandoned Pontiac? I don't know. I think Tony's conclusion is mostly speculation. If the rods were the single problem, that was so easily fixed, with you guessed it, a good set of aftermarket connecting rods. And they were available too. Pontiac people were just too cheap to buy them. Or the prices were just out of reach, and didn't need to be. Carillo, Manley, Crower, Oliver, Childs and Albert and many other AMERICAN companies were in business in the 1960's and could have very easily made rods available for Pontiacs. So just not sure the whole theory really makes sense. Pontiac cast rods were among the worst ever installed in a performance minded engine package. I will concede that.

[tom s]

I have read about the crap cast rods for years.Was it really the rods or was it maybe the “just enough” quality of rod bolts?I submit pics of a pretty catastrophic failure in one of my past engines on the highway in AZ just driving down the road.This rod although be bent did not fail?Tom

[Tom Vaught]

Originally Posted by Half-Inch Stud

Overall, the BOP 10-bolt rear constraint is a laugh, whereas GM's 12- bolt was top-shelf. Dana60 being just right.

Is why we make theY modifications.

Not saying parts of the above post are not true, but I blew up three 8.2 posi rears early one and a 12 bolt rear axle,
(as did a 64 GTO owner running a BB Chebby in his car.

You needed the service package axles to help make them live and the other internal parts in the 12 bolt posi units.
Most gave up and ran spools vs continue to buy the Chebby Posi stuff.

Just going by experience.

Tom V.

[JLMounce]

I catch some of UT's videos from time to time, so I took the opportunity to watch this one. Pretty even handed and I can't say that the rods are THE nail in the coffin, but his point is well reasoned.

We can all wax poetic about whether it was GM that forced the hand or bean counters or a "design flaw". We can even discuss the fact that the rods themselves may not be as big of an issue as the hardware used it them. The net effect however is the same. People fear factory rods in these engines. Justified or not, that is a reality. If the "performance pyramid" concept has any factual basis, by limiting the size of the top of your pyramid, you necessarily limit the bottom of the pyramid as well.

This is an inherent issue with running and umbrella corporation that covers various, but similar brands. There will always be a certain amount of competition between the child companies along with inherent favoritism towards one or a few of them. When you start making decisions for the benefit of one at the detriment of another, it doesn't always work out the way you would hope. In the case of GM, you end up with several companies creating products that are so similar that you eat into your own market share without increasing it. That'll be the death of any brand, aftermarket support or not.

[Sirrotica]

The guys not old enough to really know about what went on in the 60s, The worst thing Pontiac did is not have tight bearing clearances when the cast cranks swelled enough to not have room for oil. Rod bearing spins and the rod starts knocking and breaks the rod. I've done too many autopsies on blown Pontiacs to think the cast rods were the biggest problem in their makeup. They're not a chevy, and everything that works on a chevy, doesn't necessarily work on a Pontiac.

Open the bearing clearances up, and that stops happening. Sorry I don't agree with his hypothesis. He talks about drag racing, which is no where near as hard on the rods as circle track racing is. My engines survived multiple seasons with cast rods, but I also ran looser bearing clearances than stock. Take a used engine right out of a car, throw it into a circle track car with stock clearances, and if you get 2 weeks out of it without spinning a rod bearing, consider yourself very lucky. SBC engine have much smaller rod journals, the cranks don't grow nearly as much with heat, and require less oil as a wedge, and to cool the bearing surfaces. SBCs do blow up, but with all the aftermarket support they're easier, and cheaper to build, and rebuild. I've seen plenty of sbc engines with rods hanging out of the blocks.

He talks about Beswick switching, engine brands, Arnie trailered a bunch of cars that were supposedly superior to his during the 60s. When the 70s came around there were a whole lot of chevy guys that also abandoned the BBC, and installed a hemi in their funny cars. The guy believes he knows what happened back then, but he wasn't there, he read about it somewhere, and listened to the wives tales that have been passed around about why Pontiacs can't cut the mustard in a 12 second car. The worst thing is he's perpetuating the BS stories.

[turbo69bird]

I have t watched the video but it was always GM worried pontiac would out do ****ty Chevy. They always threw the handcuffs on Pontiac and Pontiac always had the best idea men in the game . Bunkie Knudsen John delorean, wanders herb Adams. Left to their own they’d have blown Chevy away. And taken the camaro and corvette down. GM didn’t want brands cannibalizing each other it’s well known . So they protected the corvette and camaro to a lessor extent.

[tom s]

Bean counters have been big issues in all business!How can we make it good enough but make more profit?Save enough dimes and you have saved a million dollars here and a million dollars there.Goes on EVERY day now.Tom

[mgarblik]

Pontiac did have a certain love affair with "Armasteel". Produced in large quantities by Central Foundry Division of GM. The name was part of the problem. It's cast iron! Pearlitic , Malleable cast iron. Better properties than gray iron for shafts and bearing caps, but not ideal for a high stress, high speed reciprocating part like a connecting rod. Again, fine for what the engine was designed to do with even a 25% safety factor or a little more. Carefully prepped with a lighter than stock piston, balanced really well and they would live a long happy life even in drag racing applications. Uncle Tony's little anecdote about the blower engine Pontiac blowing up says nothing to me about the quality of the rods or the engine. Maybe it was 4 quarts low on oil?, that would blow it up. Maybe he blew the tires off it showing off and it shot to 9000 RPM's? Maybe he tried to shift and missed a gear?. Maybe he built it with .0015" connecting rod clearance? Who knows. That part of the video has no meaning to me. People do stupid things all the time. Not a good example of a Pontiac "design flaw".

[Sirrotica]

Yes, the so called blown GTO incident proves zero to me, but it will keep getting repeated over, and over. Don and Roy Gay had blown GTO funny cars, with Stratostreak engines running nitro, that beat a lot of brand X cars, so his anecdote carries little weight.

As I said, the guy isn't old enough to have been there during that time period, so any of his information is third hand, at best. The guys that carried the Pontiac banner during that time, weren't blowing engines up every week like he suggests, and they were able to run 12 seconds with cast rods, even though he eludes that it was a feat that could never happen.

His stories have more than a few holes in them.

[turbo69bird]

Originally Posted by Sirrotica

Yes, the so called blown GTO incident proves zero to me, but it will keep getting repeated over, and over. Don and Roy Gay had blown GTO funny cars, with Stratostreak engines running nitro, that beat a lot of brand X cars, so his anecdote carries little weight.

As I said, the guy isn't old enough to have been there during that time period, so any of his information is third hand, at best. The guys that carried the Pontiac banner during that time, weren't blowing engines up every week like he suggests, and they were able to run 12 seconds with cast rods, even though he eludes that it was a feat that could never happen.

His stories have more than a few holes in them.

I can tell you that I own the Stephen Pontiac car, I also own a short block they had prepped and sitting on the shelf a friend bought it in the mid 70s from them after they shut down the program. The rods that are in it are similar to the 63 sd rods not cast junk, ( I belive) these were in one of Mc carthys book as mystery rods. Made in 69 but similar to 63 sd rods. So apparently they had some idea that the cast rods were JUNK - and had a Work around for it. Now I can’t say they ever raced this block crank and rods in the car because they raced the. RAII block prepped by merkel that was in the 68 RAII car as far as I know but it shows the spare they had prepped was prepped w forged rods not cast

I’ll
add that the crank in this engine was a 97954. N casting. Not an arma steel .

[Sirrotica]

Originally Posted by turbo69bird

I can tell you that I own the Stephen Pontiac car, I also own a short block they had prepped and sitting on the shelf a friend bought it in the mid 70s from them after they shut down the program. The rods that are in it are similar to the 63 sd rods not cast junk, these were in one of Mc carthys book as mystery rods. Made in 69 but similar to 63 sd rods. So apparently they had some idea that the cast rods were JUNK - and had a Work around for it. Now I can’t say they ever raced this block crank and rods in the car because they raced the. RAII block prepped by merkel that was in the 68 RAII car as far as I know but it shows the spare they had prepped was prepped w forged rods not cast

I'll be 70 in January, been playing with Pontiacs since 1970, when I graduated from high school, and started my chosen profession as a mechanic. Please don't mistake me as a damn fool that doesn't know my ass from 3rd base.

I assume the car/engine ran better than 12 seconds, the guy in the video said, as soon as you had a car running 12 seconds the rods broke. Lots of difference between a 12 second car, and a old pro stock car. I'm not so naïve, I know full well when you're running a flat out race engine, you're not going to run cast rods in it. I'm well aware of the limits of Pontiac cast rods, but they are not so brittle that as soon as a car breaks into the 12s, they fold like a lawn chair. As a matter of fact Pontiac strengthened the big end of them in 1967 by adding an extra strengthening rib to the upper portion of the big end, previous rods don't have that rib.

I ran a dirt track claimer class for $225, (67 GTO in the second picture in my signature pictures in victory lane) I wasn't going to chance someone claiming my car for $225 with forged rods in it, so I made do with prepped post 66 cast rods with good bolts. Engine ran in that car for 2 years, and when I sold the car, I sold it to a guy that put it in a 68 Firebird street car.

Moving up a class 2 years later is when I was going to build a 455 with RA IV heads, the forged 455 SD rods were going into that engine.

The rods you describe sound like RA V rods, they were forged, but still not as strong as they looked. They looked like they'd hold up well, but whether they weren't heat treated properly I'm not sure. I believe McCarthy's book said they really didn't hold up that well, from what I remember, my book was loaned to someone back in the 80s, and I never had it returned.

Pontiac did have rods that went to the race teams that were supported out the back door, but you couldn't go to the parts department of the local dealer and buy them. The only good rods that were available to the public were the 455 SD rods, and you could only buy 4 at a time, and you had to have the VIN for an SD T/A to buy 4 of them. That policy was later relaxed, and full sets were available, I still have 8 NOS SD rods in my garage that I bought from Jack Shaw Pontiac in the late 70s through a friend, same friend that never returned my book. Those forged rods were tested for hardness as there was a rumor that some of the SD rods weren't properly heart treated, so I wanted to know before I used them in that 455, that they weren't from a bad batch.

Now in your eyes, am I qualified to speak about Pontiac rods, and their inherent strength now?

[Jay S]

Back when I watched the video and fast forwarded to the section of the video that was listed in the first post, I didn’t take time and watch it all, and have never watched a full episode. So I can’t really comment much about his ideas, but about that point I started watching he was pointing out design flaws, it was ford FE’s front sump as the cause of a lot of bearing trouble, and praising the rear sump engines as better. Then explained Mopar’s were mostly all designed for slant six’s as the reason they could not use a rear sump as a design flaw.. Some real expert insight there, many modern V8’s have front sumps, LS platform to a mopar Hellcat. I guess today’s engineers didn’t watch his show.

[Sirrotica]

He now has 2 new videos of Why the oldsmobile rocket failed to fire," and a conspiracy theory of why all the flat tappet hydraulics lifters are failing. I haven't watched the olds video, but I did watch the lifter one.

According to his sources, all the lifters aren't new any longer, they're used rebuilt lifters from old engines, being sold as new......

His theory is that someone is raiding core engines for their lifters, rebuilding them, and that's why we're having so many HFT lifter failures. His buddy knows this for a fact, and his buddy is going to make a video exposing the whole scheme of used lifter rebuilding, all he needs are the tin foil hats.

His kernel of proof is, that he had a mopar engine with fixed adjustment valve train, and when he installed the new lifters there was no pre load on the inner lifter plunger with the stock valve train pieces installed, so the height is too short, therefore the lifters are remans, plucked from old engines, and refurbished.

This guy is as bad as some of the clickbait on the net, he has answers to questions that no one asks. If you can't dazzle them with brilliance, you can baffle them with bull-hit.........

I guess if your core business is failing (auto repair), you can make a living by telling tall tales on Youtube for the payment from your videos.

[NeighborsComplaint]

Originally Posted by Jay S

Back when I watched the video and fast forwarded to the section of the video that was listed in the first post, I didn’t take time and watch it all, and have never watched a full episode. So I can’t really comment much about his ideas, but about that point I started watching he was pointing out design flaws, it was ford FE’s front sump as the cause of a lot of bearing trouble, and praising the rear sump engines as better. Then explained Mopar’s were mostly all designed for slant six’s as the reason they could not use a rear sump as a design flaw.. Some real expert insight there, many modern V8’s have front sumps, LS platform to a mopar Hellcat. I guess today’s engineers didn’t watch his show.

To the best of my limited knowledge, here are the oil pump, pickup and sump locations for various "muscle car era" engines:

Ford FE ... oil pump located left front of block & front sump
Pontiac ... oil pump located left rear of block & rear sump
Mopar B/RB/Hemi ... oil pump left front, pickup & sump center/rear
Mopar LA ... Oil pump left rear, rear sump (A body only)

In each case, the pickup was located at the sump so I don't know what Tony is yammering about. Here's an OEM replacement Mopar B, RB, Hemi pan (center/rear sump - center/rear pickup):



... and a Ford FE replacement pan (front sump/front oil pump):



On the subject of rods, it is a pretty simple engineering decision for what is the optimal (cost vs performance) material selection. If operated within the manufacturer's design guidelines (RPM range), all goes well. Chevy got the forged rods as a carryover from the small block days. Buyers moved up from the small blocks to the big blocks and assumed they could wing them just like they did their old 327's. The forged rods were insurance "designed in" from the engine's inception as an NHRA and NASCAR platform detuned for the street. Pontiacs on the other hand, were street engines that were upgraded for drag racing and an ill-fated NASCAR effort.

[Half-Inch Stud]

As for racing, a group in North AL started with Pontiacs, then half of em went to the 426 Hemi when it came out, the rest including Butler, stayed with Pontiacs.