PONTIAC 350 VS PONTIAC 400-IS THERE A REPLACEMENT FOR DISPLACEMENT? YES...IT'S CALLED BOOOOOOST!

[@libertycosworth8675]

Richard fun video! A little Pontiac specific information, the 1969 62 casting heads were 72cc (10.5:1 compression) big valve (2.11 intake 1.77 exhaust heads (the '62 castings were not produced for the 1968 model year, but were likely cast in 1968 or 1969). These are essentially 1969 Pontiac 400 automatic transmission Ram Air III heads - functionally equivalent to the 1969 casting 48 RAIII manual transmission heads, and these were just one step down from the round port exhaust, bigger intake port (same valve sizes) Ram Air IV engine cylinder heads, the 722 heads. The cast iron Quadrajet 4 bbl intake pontiac used on "D" port engines from 1967-1972 was an excellent design overall, and most aftermarket intakes do not outperform it under 6k rpm.

[@jesse24933]

199 likes and 1,000 views! Let’s get the likes up for Richard !!!

[@vr6swp]

There's no replacement for displacement except for the turbo in my basement

[@garyhosier4765]

Why’s it in your basement?

[@stephen_crumley]

@@garyhosier4765because it refuses to rub the lotion on its skin

[@garyhosier4765]

Bahahaha!!!

[@Lori-jw8lx]

​@@stephen_crumley better give it the hose again..mabey even some auto trader mags.

[@happycat0411]

I had a stock 1973 Formula 455 Firebird and my brother had a 1986 Grand National T-type (Turbo Inter-cooled) and whenever we raced head to head from a standstill I would always easily take the GN due to the sheer torque of the Pontiac 455. However from a roll the GN could stay side by side all the way through the entire 1/4 mile! I never would have imagined that a 3.8 turbo inter-cooled V6 could generate enough HP to keep up with a big block 455! Boost is nice as you can generate the turbo's extra boost by simply mashing down the gas pedal! Otherwise the V6 will perform like any other normally aspirated V6 when the turbo isn't working!

[@JudgeMeNotLeMans]

@Richard Holdener Just love the Pontiac stuff!!! The #62 heads on the 400 are 2.11” / 1.77” valves and 72Cc chambers around 10.5:1 CR. The 350 #47 heads are 1.96”/1.66 and 8.6:1 CR. So the 400 had everything going for it until you boost it boost it… as for aftermarket aluminum heads there are a few who make 350+ flow numbers and they’re not edelbrock. PONCHO POWER!!

[@Boatanchorperformance]

I removed the #47 heads off my 350 and put on #62 heads lol. Nice lil bump in compression and breathes a lil better with the bigger valves.

[@JudgeMeNotLeMans]

@@Boatanchorperformance Nice! I managed to acquire a set of #16 heads from a 421 to put in place of the 6X-8 heads on my 455.

[@bmgineer]

So if you add the same boost to the larger engine you get more power. So displacement still wins.

[@deadtodriving]

Exactly. That is when I stopped watching the video

[@CzechSixTv]

@@deadtodriving The point, which is poorly demonstrated by comparing 2 Poncho V8's since the engines are identical in size physically and nearly the same displacement, is that boost can more than make up for a lack of displacement. My Incon TT 331 Ford was capable of over 700 HP and guys like Jason Betwarda were making 1500 HP from the same displacement. Sure there are 700 HP naturally aspirated big blocks. How many have you seen making 1500 without boost though??? It can be done but it will be a radical track only motor. There are guys right now street driving turbo LS and Coyote motors making well over 1200 HP. Yes a bigger engine on boost can potentially make even more power, and again 2 Poncho's are a bad example, but larger displacement engines are usually physically bigger and heavier. Have you ever seen a big block shoehorned into something like a Fox Mustang or 3rd gen+ Camaro? I've been in both and they handle like crap. Even my '71 SS with its factory 402 was very nose heavy and would constantly oversteer. My buddy's Vortech supercharged Iroc could absolutely smoke my '71 in a drag race and still handled like a slot car. If you are building a dedicated race car, not subject to displacement restrictions, go as big as possible and boost it as well. That's obvious. If you want something fast that can't physically fit a BB without throwing the rest of the car all out of whack though, you can still get the same or more power with a smaller boosted engine.

[@bobsilver3983]

I have a 1968 Lemans 350 H/O 320 hp, 126,000 miles never rebuilt and it runs great and pulls hard.

[@richardholdener1727]

I'm Jelly

[@TrevorMcGary]

You can boost big engine’s too.

[@doctorwhodj]

That OEM iron pontiac intake is hard to beat maybe beat by an RPM if not by much... The performer is best for a small displacement stock build. Ive read pontiac did their homework in that intake

[@arnoldpalmer9897]

Definitely the best performing. I have Holley and Edelbrock aluminum intakes sitting on the shelf, only thing better about them is the weight. If someone did a stock Pontiac intake cast in aluminum they could make some money

[@albertgaspar627]

When Pontiac 400's were easy to find in the junkyard, the notion always was the small bore of its 350 brother was a problem. funny thing...the bore and stroke are pretty similar to an LS1 346 cid V8. no one questions how well they breathe. so how do they do it? by making the port tall rather than wide, and having a Y block/deep skirt scenario that increases crankcase volume. so as the pistons run down to BDC, they aren't compressing the atmosphere inside the crankcase as much, causing resistance. The Pontiac, meanwhile, has a wide crankcase, achieving nearly the same benefit, and the valve angles are close to what helps the LS engines breathe better. all they need is a cathedral port, and they'll be a "cheap" LS (which is a bit of an oxymoron until the 5.3 litre LS reaches peak demand and prices for it rise up to the 6.0 level...but no one makes 350 pontiacs anymore, so they'll only go cheap from owners running to the LS bandwagon). what we didn't know then....but now we do.

[@richardholdener1727]

they don't need cath port heads, they just need better heads

[@albertgaspar627]

@@richardholdener1727 true they could use better heads (can't we all :) ), but with a small bore to work with, a narrow port that is tall will move volume to reduce shrouding by the cylinder (unless it's a flathead, then the valve diameter total can exceed the bore diameter). the issue of course as always, is quality over quantity. a tall narrow port isn't going to have a lot of flow at its floor, depending on its valve angle. a "big gas hole" isn't enough for a good head design, as we already know. Looking at my old 400 heads standing up in the garage, there's not a lot more port roof to cut into on an OEM head, but an aftermarket head could shape itself any way it wants. there were some 6X heads Pontiac used on the 350 that would be interesting.

[@jjtool5800]

Yeah but what if you boost the larger displacement engine? There is still no replacement for displacement

[@tomcherry7029]

Boost is a change in displacement. You are forcing more air /fuel into the engine, which is changing the amount the engine displaces.

[@richardholdener1727]

displacement remains the same-boost multiplies the NA power output regardless of displacement

[@melvinharrison9138]

Pontiac #48 #66 #670 #722 Cylinders big valves on the intake, and exhaust on 350 will increase horse power with a dual pattern cam "lunati" has the profile!💯🤔

[@pancudowny]

Richard: I'm part of an enthusiast group of the 1970's GMC "Trans-Mode" RV motorhome, and a common question had amongst fellow members of the group is "What do we use to re-power them when the factory-installed Oldsmobile 455 or 403 fails, and there's a shortage of rebuild-able cores?" Needless to say that with the THM-425 trans-axle (Turbo 400 twisted & with a diff.) the choices made must involve concerns and sustained mid-to high-RPM operation, as well as sufficient low-end torque and fuel efficiency. This is where questions about turbocharging the Oldsmobile 403-ci.--or even the Olds 350-ci.--V-8s come into play as to seeking a solution. Is it possible to make 455-sized power from eithe 6.6L or 5.7L of Olds V-8? And do it on an affordable, commonplace fuel? (Pump gas 92-octane or E85) All without breaking the bank?

[@richardholdener1727]

yes

[@albertgaspar627]

don't forget the diesel 350--oldsmobile companies will not only convert it to gas, but with a machined 425 crank (forged like your 455 toronado cranks) you can get 400-454 cid out of a small block that will accept your big block heads. time to stock up, while these go for cheap from owners looking to LS swap.

[@Guns_N_Gears]

Sure, if you can do it with a 4.8, no reason you can't with anything else. The 455 won't rev as high stock as the 4.8, but I don't believe that's what your after anyway.

[@albertgaspar627]

@@Guns_N_Gears the nice thing street rodders found when they ditched the targetmaster 350 for any BOP big block, was it made torque down low, so they had vacuum for accessories and decent MPG out of a 3 speed without an OD unit hanging off its back. and the big blocks didn't weigh all that much, the Buick 455 was like a cast iron headed 350. not sure what a 4.8 would move, don't they run 8100cc rats in motorhomes?

[@tsmith578]

When I was young one of my friends had a 1971 Lamans with a 350 4brl in it that we had rebuilt, I can't give ya an exact figure for horsepower or torque, but I would say it was probably in the neighborhood of 300 horse and about 375 torque, cause we had tested it with a compression gauge and it had 180 psi in each cylinder. Now mind you it's not a rocket with nitro or a turbo or anything like that. Them old pontiacs rev up pretty darn good and coupled to a good th350 transmission and about a 355 gear in the axle and it is a good recipe for a fun Saturday night.

[@mstsuc2bu]

I wish I could get my Olds 455 to you. Just to see what you could do with it.

[@mattrodgers4878]

I’d be happy for some Oldsmobile engine tests.

[@markwegner6100]

Boost it!!

[@jtr499]

Thank you, someone finally said it out loud!

[@scottlehmann9085]

Can't you boost the larger displacement too? If so, there is still no replacement for displacement.

[@phildo39645]

Owned both and they both ran very strong..! Good motors for sure.

[@jellytheninja]

I like a win-win, displacement and boost!

[@takeit2-11]

When you gap the old rings and put them back in for your junkyard turbo tests do you hone the cylinders or just pop those babies straight back in there? Thanks!

[@richardholdener1727]

I have done it both ways-usually just add gap and put back in

[@matthewperry6506]

Only displacement over time matters, cid, rpm, boost etc.. all contribute.

[@albertgaspar627]

displacement only matters when we speak of modern pump gas. those who have E85 on every corner can run boost affordably.

[@tsmith578]

Man Richard I really enjoy all your videos and all the effort you put into making them, I'm a bit more of what all these young people call OLD SCHOOL, where as I just appreciate a good old V8 or inline 6 cylinder engine with a carburetor. My father used to say just tune em up for making maximum torque, because that is what what you need to move weight, and if you have a properly built engine it will make sufficient horsepower So can you make a couple videos of concentrating on making torque and show us all the results on the Dyno.?

[@malamri424]

Hey Richard can you do a compression ratio test? compare power and fuel requirements... Thanks!

[@tsmith578]

Did you test the compression at all on either of the engines? I thought that you would have at least tested the 350 when you were diagnosing the running issues it had when you first tried it out

[@richardholdener1727]

it had even compression

[@RobsNeighbor]

Great Job Richard! You are always bringing great valuable content almost daily! Thank you

[@moonburnt_garage]

Great video as always. My boosted 350 Pontiac looks to have popped a head gasket as it now over heats when it never has. I have been looking at upgrading to a 400. And boosting that. Comes down to the deal really. I was guessing about 400hp with 8psi on my 350 based on draggy results. I am guessing Boosting a 400 is next on your list???❤

[@takeit2-11]

Very cool, love that boost! turbo magnum! turbo magnum! turbo magnum!

[@ElaineCottrell-u2e]

Could add boost to the 400 and then would the 350 have a chance to make as much power? Love your video’s How about doing a 390 Ford and a 429 Ford? Love the Pontiac videos, I just got an Duel Quad Edelbrock manifold for my 400 Pontiac Trans Am , it has a single plain high rise intake on it now. It’s cammed and headers and it really turns on in the upper rpm’s , so I don’t know if the Edelbrock duel quad is going to help on the low end on hurt on the top end, I’m hoping for better bottom end and still have the high rpm it turns now.

[@richardholdener1727]

IF THE DUAL QUAD IS A DUAL PLANE, IT WILL HELP DOWN LOW COMPARED TO SINGLE PLANE

[@bryanhinds8522]

nope there is no replacement for displacement! what you do to the tiny engine you can do to a big engine! 🤣👍

[@nucleargrizzly1776]

400 + boost... Problem solved

[@stevechaffee2360]

Oh wow What are the odds! If the 400 is stock and matching to those 62 heads that's a identical twin to the motor in my 69 GTO think the were rated around 360hp

[@ericthompson3551]

Did you get your stock 350 from my 69 LeMans ? I haven’t looked under the cover in a couple months and you described it to a T.

[@hoost3056]

Im a Pontiac fan......but a pump is a pump regardless of who makes it. Boost and Pontiacs are natural like boost and Fords.

[@blainesnider9089]

Unless you turbo the bigger motor

[@jhutch1470]

Just the bore alone makes a big difference with the 400. Get it?

[@davidreed6070]

Those old GTOs in the day ran pretty good.

[@bernardcoleii4418]

My 1978 Camaro Type LT had a manifold that used a hot air style choke, 350 Engine was handbuilt at a local VA Shop. Car would bury the needle at 130mph no problem, plus took out 2 rear-ends and 3 transmissions in just 2 summers! Had HeI style ignition just wondering what hp this engine was putting out and the manifold must have been older to have the old hot air style choke? My right question is what kinda horsepower would this motor making to do what I said about? Tour 2 two 350 trans plus 2 set of gears. From and old but built 350 junk q-jet carb

[@richardholdener1727]

introducing hot air is for fuel mileage and to help it warm up, it will not help power

[@erickbernard8208]

I remember turbo honda guys saying this God created turbo lag to give V8s a chance 😂

[@pancudowny]

I should've figured you attack this notion eventually: What if you put a turbo on the the most unloved Pontiac V-8 (The 4-cyl. can wait... until you've done the same with the Sprint-6, that is.😉) of the muscle-car era? And now we know...!😊

[@theidahomegarage8090]

Id love to see a cam swap in that pontiac 350.

[@richardholdener1727]

ME TOO

[@JH-oh1in]

I view forced induction as variable displacement engines. VE up or down on demand.

[@jtr499]

So many missed your point Richard.

[@alanarmstrong2323]

There is a diif are you running a 350 ho or 400 ram air 5

[@michaelsulkoske4373]

I really don’t understand what an LS has to do with a Pontiac comparison. Just a guy who likes to play with charts.

[@TAWS-wq3hx]

Those smaller combustion chambers, Chevy copied Pontiac. Very simple

[@77chevy4x4]

Pop said 350 had smaller bore but stronger than overbored 400 hood cores shift and RpMs better .. hmmm let’s see 😊😂

[@ericwilson2585]

I don't know.... From what I've seen of Pontiac engines from back when I was a kid, Pontiac engines weren't very well known for durability, and it seems like it wouldn't last very long with boost unless you put in all forged and balanced internals. And I don't know how many Pontiac cams I've seen go flat.

[@hayden6056]

The rods are modular cast iron compared to forged steel like the big block Chevy and over revving was the main issue with them the bolts would stretch first then the rod would break. Forged rods fixes the issue I wouldn't personally rebuild a naturally aspirated Pontiac without forged rods. The $4-700 cost is well worth the upgrade.

[@nucleargrizzly1776]

Around '71 Pontiac though it would be a good idea to make their blocks (non SD or HO) thinner and weaker.

[@hayden6056]

@@nucleargrizzly1776 then again in 75-76.

[@maxpowerta3183]

@@nucleargrizzly1776 False, the 350/400 blocks were weight reduced and weakened in 1975 (with the exception of the 78-79 W72 Trans Am engines).

[@nucleargrizzly1776]

@@maxpowerta3183 So what year did the 4 bolt mains decide to start running off?

[@jasonbirch1182]

Have you ever messed with german(or a vega☠️)engines with the alusil block with pistons directly in the block? Its fine for NA but turbocharging it makes me nervous. Thoughts?(just kidding with that).

[@richardholdener1727]

I have not run them, but have seen turbo Cosworth Vega motors

[@donreinke5863]

Seems pointless to spend the money for turbo/superchargers when once can simply build a 400 or even a 455 and likely have less money overall as I sure wouldnt want to boost a non-rebuilt engine of any type.

[@russelljackson7034]

Right on

[@DillonAuto]

The stock 350 dyno result looks a lot like the stock 5.0 dyno result. Just a little better.

[@davidreed6070]

Richard, you have messed with these LS engines so much you will likely know this. What should the cranking pressure be on an ly6 with a 230 @.50 cam.

[@richardholdener1727]

DON'T KNOW-IT JUST NEEDS TO BE EVEN-I DO KNOW EVERY 230 CAM WON'T HAVE THE SAME CRANKING COMPRESSION

[@davidreed6070]

@@richardholdener1727 absolutely correct but the more int. dur the cranking pressure will lower. This engine has 150 All around. I'm thinking the chain might be one tooth off.

[@truthseeker2190]

Boost? They spin rod bearings under normal circumstances

[@mikeclark740]

Dam I want to do that for my Nova with a LS

[@keithsmith9889]

No replacement for displacement?? But boost is isn't it...hmmm lol. Whomever originally said that is rolling over I'm sure

[@drewskiient5071]

Would boosting a stock pontiac 350 hurt?

[@richardholdener1727]

not if the motor is sound and the tune is correct and boost is reasonable

[@forterierocks]

LS engines love boost!

[@ericbridges9]

still waiting on the stock 396

[@ChicagoRob2]

Me too

[@jonnelson3663]

Put a m90 on a 4.3

[@freezinghotshot]

Boost IS displacement 🤔

[@hondatech5000]

Turbo>stroker+hci

[@scotttimpany2845]

Let there be boooost!!

[@joseboyd4563]

Honda. Thats enough said as far as displacement.

[@tomcherry7029]

You are just looking at things in rhe wrong way. , displacement is relative, if you understand basic principles. Cubic inch displacement is the amount of air an engine can move of "displace" boosting an engine is just forcing the most air that an engine can fit/handle . So if the atmospheric pressure is 14.7 at sea level and you add 14.7 lbs of boost you are dubbling the displacement so a 2.0L engine running 14.7 lbs of boost at sea level is the same as a 4.0L engine.

[@richardholdener1727]

you don't double displacement, you double output

[@tomcherry7029]

@richardholdener1727 your are increasing the amount of air that the engine is moving to increase its output. So yes, you are, in fact, increasing how much the engine displacement.

[@rickuyeda4818]

That's just stupid since you can boost the 400. Only the SD 421 and the 389 had a forged crank. Blah, blah, blah,,,,,just get to the point!

[@fellsmoke]

Bigger 400?...the pontiac block regardless of "size" is the same size...

[@richardholdener1727]

a 400 is bigger than a 350-it's just math

[@fellsmoke]

@@richardholdener1727 aspects of build build bigger results...blocks are the same size for the Pontiacs...

[@brendanneuman8202]

Is boost not displacement ? A Maggie 2.3L displaces 2.3L of air per revolution. The replacement for displacement is efficiency!!! Look at all the small modern engines making big numbers!

[@edmundmaitre8738]

I would not trust anything you say because you don't know the difference between engines and motors !!!!!!

[@richardholdener1727]

You should contact Ford Engine Company and General Engines to complain

[@geranwilson8813]

Just think if you took a super duty455 And added a Supercharges turbo charges Are a blower. It would totally shred an LS motor. Turbo charges superchargers and blowers are only for Incompetent Shea tree mechanics who Lack the balls and cannot build a real motor and make serious horsepower and Torque🤣😆🤣😆🤣