A intake manifold seperate from the block with a valley pan? And why did the engineers decide to incorporate the timing cover with the water pump and attach it at the bottom with the oil pan? I hate to say it but I actually prefer the way a small block chevy has a seperate timing cover from the water pump. The whole valley pan and "air gap" type set up on a Pontiac motor is nice I guess for keeping engine heat away from the intake manifold, right? Any other questions you guys ever ask yourselfs about "why did pontiac do this with their motors?" feel free to post 'em.

-Adam

A intake manifold seperate from the block with a valley pan? And why did the engineers decide to incorporate the timing cover with the water pump and attach it at the bottom with the oil pan? I hate to say it but I actually prefer the way a small block chevy has a seperate timing cover from the water pump. The whole valley pan and "air gap" type set up on a Pontiac motor is nice I guess for keeping engine heat away from the intake manifold, right? Any other questions you guys ever ask yourselfs about "why did pontiac do this with their motors?" feel free to post 'em.

-Adam

Pontiac Engineering "Good Ideas"

1) Air Gap manifold keeps the intake charge cool

2) Intake mainfold can be removed without having
to remove the distributor and "retime" the engine.

3) Valley pan gasket can be one piece vs 4 on
the Chevy.

4) Built in Oil Separator on valley pan vs a
separate pressed in part in the valley on the
Chevy.

5) Water pump design allows for superior cooling vs a Chevy using factory parts. A stock
cast impeller Pontiac pump has better flow than some "racing" pumps for Chevys.

6) Deep timing cover allows one piece cam excentric /fuel pump lever contact with the fuel pump
vs needing a fuel pump pushrod. Fuel Pump excentric
goes bad on a chevy (part of the cam) you replace the cam and the lifters. On a Pontiac the cam and
lifters do not need service and you change a cheap part.

7) Pontiac uses a Cam Thrust Plate to hold the cam in
the correct alignment under the timing cover. The Chevy needs a special "Cam Button" or reinforced
timing cover if you put in a high perf cam.

8) Pontiac timing cover has provisions to raise the
engine from the bottom (motor mount bolts removed) to
remove the pan on some engines. The Chevy has no cast
in provisions to support the engine.

9) A Pontiac Timing Cover (using a balancer spacer)
will allow a Motor Plate to easily be installed under
the timing cover and the plate will be mounted securely by 6 bolts. The Chevy block has a couple of
bosses on the front of the engine that allow engine
brackets to be installed but the design is not very
strong for high hp engines.

And the list goes on and on.

Tom V.

The oil filter bracket boss on the Pontiac engine makes it much easier to do the remote oil filter thing. P.S., If you do a cam button on a chevy, you had better use a reinforced timing cover too.

The intake manifold/valley design on a SBC allows engine oil to splash up under the intake exhaust crossover runner. This oil 'cokes" and turns into ugly black residue. Hard to keep your oil in good shape for extended periods with this design.

George

The thing that amazed me about my first Pontiac rebuild was the strange cheap-looking, loose-feeling fuel pump eccentric bolted to the front of the cam gear. I thought "this can't be right" and ordered a new one, only to find it was the same. I think that is clever design when you can make cheap stamped parts work so well.

Ever try removing the timing cover on a Chevy smallblock, at least on the earlier ones? You will have to loosen the front of the oil pan to get it off, it was designed to be installed before the oil pan goes on. Pontiacs have a nice flat flange between the cover and the pan, easy to remove for service.

How about pushrod guide plates? All Pontiac engines built since '67 have them. Even screw-in rocker studs that only came on high-performance Chevy engines came on every Pontiac engine since '74, and on many common 4-barrel engines since '67.

Best of all, in nearly all cases you can directly swap a smaller displacement Pontiac (326/350) with a bigger one (389/400.421/428/455) by merely bolting it in! No need to change exhaust manifolds/headers or accessory brackets to a different type for the big injuns, unlike a Chevy. The Pontiac V8 was/is the first truly modular engine.

Pontiac engines have many nice design features like Chevy engines have and then some. http://forums.performanceyears.com/g.../icon_cool.gif

Every time I work on my 455 i'm reminded of how thoughtfully engineered the engine is, and how in many ways it was ahead of it's time. It is amazing to me how pontiac with one basic form factor (well, there was the 301...) made a complete family of engines of all sizes, with major interchangeability.

Another couple of interesting/advanced OEM features are the factory oil splash guards over the rocker arms and the factory windage tray.

- On a Pontiac the starter is on the same side as the battery. Shorter cables, easier routing.
- The A/C compressor is on the same side as the suitcase. Shorter hoses, easier routing.
- Pontiac was the first to use the rocker arm/pivot ball arrangement.
- Pontiac only has 1 flywheel tooth count.
- Pontiac doesn't use a rubber hose to connect the water pump/timing cover to the water crossover.
- Pontiac (BOP) uses a larger u-joint.
- Pontiac (BOP) uses bearing-retained axles.
- A puller normally isn't needed for swapping harmonic balancers.

Spark plugs are very easy to change http://forums.performanceyears.com/g...n_rolleyes.gif

While replacing a header gasket the other day, I
said to myself "their better be a good reason they turned down these exaust ports" anybody know?

Actually, I can't believe someone would view these things as negative. One of the reasons I like Pontiacs so much is becasue of the features you mentioned. I HATE the way chevy engines are assembled and could never see myself running one again. as for other engines, the reason I decided to put a pontiac 455 in my Jeep we because the AMC oiling system made me think my investment would destroy itself after 60,000 miles. steel oil pump gears in an aluminum housing? no way Im building an engine that is oiled that way. Pontiacs may have oiling issues too, but at least they have a REAL oil pump! Once you go PontiAC you never go bACK .... http://forums.performanceyears.com/g...on_biggrin.gif

<span class="ev_code_RED">Please remain calm. This is a hijack.</span>

skid,
What kind of Jeep and do you have pictures? A friend of mine is majorly into Jeeps and I would like to show him your setup.

<span class="ev_code_RED">You may return to your previous topic now.</span> http://forums.performanceyears.com/g.../icon_razz.gif http://forums.performanceyears.com/g...on_biggrin.gif

Dan

You forgot a couple more good things. Most of combustion chambers fully machined. Where most chevy chambers were rough cast.

pretty flat valve angles for flat chambers with good quench. Why are all the chevy guys running heads with flatter valve anges.

You can get a 350 or 400 cubic inch motor with 2.11 and 1.77 valves from the factory.

Pretty good rod to stroke ratios. Especially 400.

Don't know too many street engines that can run low dollar with a 455 besides maybe a buick.

The only drawback i can see is cast rod (above 6000rpm), lack of inexpensive aftermarket hi end parts and thin pan rail for sealing.

Why all the chevy bashing? Every time a question comes up about engine design, everyone jumps on Chevrolet with both feet! No comparisons are made to Ford, Olds, etc. I dig pontiacs, so don't get me wrong.
Chevy's intake manifold was designed to be the top part of the engine for added strength, when have you ever seen a lifter valley brace on a chevy?
The bolt on fuel pump accentric is because of the fuel pump mounted farther foreward on the block, really, has anyone EVER seen a chevy cam lose a fuel pump eccentric?
Chevy's cast combustion chamber seems to do the same thing as the pontiac's without the expensive machining process.
Chevy's water pump is serviceable by removing 4 bolts, and if it rusts through from owner neglect, it doesnt dump coolant into the oil. also a motor plate bolted under the water pump isn't only easier to make, it is as strong as anything designed by other brands.
Chevy's are also a whole lot easier to put headers on.
And the list goes on....

I'm not just stirring up crap here, like I said, I like Pontiacs, but why not bring up pros and cons about ALL makes, not just the Chevies? If pontiac engines were so superior, why are they not the "Corporate" engines of today? just a thought.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Dan&Dot:
<span class="ev_code_RED">Please remain calm. This is a hijack.</span>

skid,
What kind of Jeep and do you have pictures? A friend of mine is majorly into Jeeps and I would like to show him your setup.

<span class="ev_code_RED">You may return to your previous topic now.</span> http://forums.performanceyears.com/g.../icon_razz.gif http://forums.performanceyears.com/g...on_biggrin.gif

Dan <HR></BLOCKQUOTE>

Yes, as a matter of fact, I did a temporary install of the empty block and transmission case today to measure for building new mount towers. Turns out, it is a close fit, may not have have to do alot of fabricating... I can post pics, but dont want to hijack this post too bad! want me to email them? or I can start a new topic, that is if anyone cares to see an installation of a Pontiac 455 in a Jeep Cherokee.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by meanken:
Why all the chevy bashing? <HR></BLOCKQUOTE>

Maybe (at least on this thread) it's because the opening post on this thread made the comparison:

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>I hate to say it but I actually prefer the way a small block chevy has a seperate timing cover from the water pump. <HR></BLOCKQUOTE>

No one here is chevy bashing it's just the most popular engine and to compare to everyone else would take forever. There are alot of good things about chevies like i agree i like their water pump setup too. But my opinion is the pontiac motor is better. And the reason GM went chevy is simple. More chevy motors were produced because they offered more models cars and trucks and were cheaper to build. Cheaper motor for gm to build = save money. The lifter bore thing is very simple pontiac designed the motor for LOTS of low RPM torque no need for square cam lobes. And by the way the open lifter area is good for oil drainback and it's easier to adjust the rocker lash.

I will never complain about the angle for Pontiac headers. The extra time spent is more than paid for with the ease of spark plug changes and lack of burnt plug wires.

Besides, the only really hard bolt to tighted is the rear one on the center exhaust.

AHHHH! Come on guys, lets here some testimonals from the other SIDE!!! http://forums.performanceyears.com/g...on_biggrin.gif

Were the hell you at inbred?

Does that sound southern?( you know, were for where and stuff )
If not it must be this DAMM Hennessy.

I have changed many chevy cams because the fuel lobe was ate up. During the 80's, chevies were using such garbage for cams that it is a wonder gm didn't go belly up repairing them. As for the water pump, it's a nightmare if you break a bolt in any engine. And as for the intake story, that applys to every engine. The Pontiac down turned exhaust ports were for easier exhaust under chassis exit and to prevent burned plug wires. Oh, on the easier to put headers on a chevy thing, not in an S10 !!! But I'll get into that little project of mine another time. hehehehe

Yeah, I remember the notorious Chevy cam problems. I replaced a bunch of em too, but they all had the lifter lobes ate off of them. Boy did I make a bunch of money on those, and got pretty good at changing them too. (at first GM wouldn't pay warranty on them)
And a 15 minute Pontiac intake swap just can't be beat.
I wasn't being ugly, It's just always Chevy that gets brought up into this topic and I was curious as to why. I guess it does kinda make sense since it is the most abundant one out there. Carry on, gents. http://forums.performanceyears.com/g.../icon_cool.gif

Interesting to hear Edelbrock brag on their "revolutionary" new Air Gap intake design, worth 10 hp, they say. When customers ask me to explain, I just use a Pontiac intake as comparison, usually the RAIV, just to make my point, and explain to them that it was a NASCAR design initially. Also tease them about screw in studs, oil deflectors and windage trays, which they don't have. pontiac went to "rollover" heads in '67, from 20 degrees to 14 degrees, whereas Chevy still uses the 23 degree design even though it is proven tha the 18 degree makes more power. I won't even go into Fords. Pushrods? What day was your car made on? Do you have shaft, rail type or pedistal mount rockers? What is the deck height of your small block? What a cluster!

Reading through all of these replies has given me a new respect and appreciation for the innovations and designs that the Pontiac engineers developed such a long time ago. Makes me even more proud to be a pontiac nut instead of your run of the mill chevy/ford guy.

http://forums.performanceyears.com/g.../icon_cool.gif
-ATF

skid2964, you could post your Jeep project in the Non Pontiac Motors in Pontiacs section of the forum, its also for Pontiac engines in other makes. I would like to see you keep project,as this is something Ive thought about doing in a Jeep J series pickup. Soory about the hijack.

Having owned and worked on many different cars and engines, sounds like Pontiac should have moved the distributor up front. The it would be almost perfect. http://forums.performanceyears.com/g...icon_smile.gif

I recall someone once explaining that decision also..

anyone??

ATF204 - this thread explains some of the reasons some of us "old-timers" prefer real Pontiac engines to the corporate bowtie small block.

Jon.

the only thing that frustrates me about my 389 is the distributor in the back of the motor. its so cramped back there. then again i did own my buick engine before the pontiac so im just not used to it being back there.

Real men wear bow-tie or do I have that backwards.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by pontiac6269:
skid2964, you could post your Jeep project in the Non Pontiac Motors in Pontiacs section of the forum, its also for Pontiac engines in other makes. I would like to see you keep project,as this is something Ive thought about doing in a Jeep J series pickup. Soory about the hijack. <HR></BLOCKQUOTE>

Yes, I will do that ....

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> the only thing that frustrates me about my 389 is the distributor in the back of the motor. <HR></BLOCKQUOTE>

Get hold of BOP Engineering. They can get you all setup with a front mounted distributor.
http://www.bopengineering.com/beltdrive_acc_front.shtml

has anybody said anything about the part swapping of a pontiac motor vs chevy. pontiacs all interchange from 326-455, cranks on 326-400only rods on all heads,intake, exhaust, chevy certain small blocks, no part swapping onto the big block chevy.

One issue with a front mounted distributor is the oil pump. Most GM apps use a rear sump pan, so you have quite a distance to prime that oil pump. Cadillacs had this issue also.

A LOT of Super Street high horsepower Fords
use a normal front mounted pump and a rear sump with long pick-up and have no issues with the
pump getting a prime.

You MUST securely mount the pick up tube for the
pump near the screen or it will eventually break
and you will have an air leak and loss of prime.

As more and more Pontiac guys embrace efi technology
you can have the coil packs near the front of the engine and never have to go near the back except to initially install the cam sensor/ oil pump drive.

Butler's engine has this provision on it. It also will
allow a better tunnel ram design intake manifold with
the distributor gone.

Tom V.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by meanken:

I'm not just stirring up crap here, like I said, I like Pontiacs, but why not bring up pros and cons about ALL makes, not just the Chevies? If pontiac engines were so superior, why are they not the "Corporate" engines of today? just a thought. <HR></BLOCKQUOTE>

The fact that Pontiac power did not become the "corporate" engines of today had absolutely nothing to do with which engine had the best design. It was a bean-counter decision. Chevies always were GMs baby because they sold the most cars. There was always preference given to chevies. Recall GM's tripower ban after 1966? Why could you get tripower in a '67 corvette? Or how about motors no bigger than 400 c.i. in mid-size cars? Why could you get a 427 in a corvette or camaro?

Considering the many advantages listed in this thread, imagine what kind of engine the Pontiac motor would be if it WAS the corporate motor of today? Besides the few after market companies doing the minute amount of develpment, R&D for this motor has been dead since 1980. At yet is still lives, in fact, it's thriving more today than ever!

BTW, Juliano...it's "bowties are for sissies!"

Been reading the thread and have learned lots of interesting stuff as the 455 for the wagon is the first pontiac V-8 I have worked with, And there are some things I like about it and others, chevys (the other v-8 I have worked with)are better, But one thing I havn't seen really explained.
What is with the water pump set up? The intermedieate plate and the bushings?
When I took my heads in to be done, the old guy in the machine shop talked about how to make sure the bushings were ok because it was a common mistake to make on the pontiac motor to leave them out and have an overheating problem. So was there an adbantage to the design?
BTW the project is almost done. Too much stuff getting in the way.

I don't know exactly why they made the setup like that. My personal opinion is i like the chevy style water pump better but i have never had any problem with it. But i have heard that the pontiac pumps have a bigger impeller and i guess the housing has to be larger. Any one else have any comments?

On the Distributor in back part, if I remember right, there was a fear of water drowning problems. Also since the chassis required the rear sump, it was easier to have the distributor at the back of the engine to drive the oil pump. They never imagined the kind of pressures the modern race stuff puts on the cam as far as twist when the oil pump is also driven at the other end of the cam. Todays spring pressures were unheard of then, as the most radical cams and valvetrain was not much more than a now typical flat tappet cam set up. Do you realize the Pontiac V8 design has been in use 50 years this fall? That is an achievement !!! And just think, chevy borrowed many ideas from it to get their small block in production. So hats off to the Pontiac engineers of 50 years ago.

One point I forgot to mention. The GM board decided to keep the chevy engine because it was in production in nearly every country GM sold vehicals, Mexico was also the cheapest labor cost. Pontiac did not have engine plants all over the world or in Mexico.

Along with the many great design ideas Pontiac had there are a couple elements that seem like they could have been improved;

The water passage between the back of the timing cover and the front of the intake manifold. Pulling the intake towards the timing cover with that slender bolt can alter the alignment of the ports in the heads to the intake. Although sawing off the front of the intake solves this and allows for a dry intake swap...I would have prefered a short section of hose ala Olds or BBC.

Non adjustable valve train - decking the block or shaving the heads can really foul this up if you're sticking with the factory system. I guess it's easy enough to convert the heads to an adjustable system, just kind of a puzzlement why the non-adjustable design was held to.

Out of curiosity, which other major Engine designs used a non-adjustable valve train? Was it more economical to build on the assembly line? Was it less prone to problems for the duration of the warranty?

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by silver:
Out of curiosity, which other major Engine designs used a non-adjustable valve train? <HR></BLOCKQUOTE>

Two that come to my mind are the oldsmobile and ford windsors.

I think Buick also was non-adjustable. I'm suprised that no one mentioned that chevy claims they are the first to introduce reverse-flow cooling(the LT1)&gt; Pontiac had this idea covered in 1955, but the tubes in the heads would clog up creating warranty problems. Was this becouse people were neglecting the cooling systems. Has anyone tried to copy this design on a 400 or 455 and document the differeces in power?? http://forums.performanceyears.com/g...on_biggrin.gif

http://forums.performanceyears.com/g.../icon_cool.gifyou want bashing for the other engines too? AMC, like Pontiac and the small block Chevy, Outside block size stayed the same but bore and stroke changes for more cubes.
BUICK, Differant engines bolted up to same tran's bolt pattern... BOP

Unlike Ford, Small block, small block trans, Big Block, Big block trans, FE engine? Didn't match anything but FE. 3 differant 351's C, M, W. No interchange: but 289, 302's probably the best engines Ford made, besides the straight 6 300.

I HAVE A SAYING: IF YOUR BEHIND IT AND YOU CAN SMELL IT, 9 TIMES OUT OF 10 IT'S A FORD!!!

Dodge, Chrysler, Plymouth: Small blocks, Big blocks, Wedge, Hemi....nothing more need's said here.

I think that if the aftermarket providers would have got on the band wagon and made more Pontiac HP parts then the chevy's way back then. The Pontiac engine might have been around a lot longer. But, you have to remember that when the GTO's first came out everyone had to put HP stuff in just to stay with them. That's why you go into a parts store today and see Ford and Chevy HP parts. They are still trying to keep up!! But seriously weight means HP, which mean's fuel consumption and with that, GM went with the easier engine to mass produce and change with the times. They are also a lot lighter (HP per Pound) then the Heavier Pontiac mill. Just remember that Pontiac came up with a lot of the Ideas that are still in use today on internal combustion engines.

AMC CU IN up to 401
CHEVY CU IN 265-400
PONTIAC CU IN well you know!!!

All I know is back in 1973 I wish I had the pictures of the faces of the two friends of mine that had chevys after a little high speed race on the way home one night after a football game. It seems that my buddy with his 1969 Chevelle SS 396 opened up my hood at half time and went in and pulled a spark plug wire. They figured that on the way home they would challenge me on the highway and make my car look bad. The joke was on them when my 1968 400 GTO blew their doors off. I noticed the miss but it a not uncommon for me that after sometime of slow running the spark plugs got funky. They tried to pass me on a long stretch of highway up here in Wisconsin and never even got to my doors before I pulled away. IF I ONLY HAD A PICTURE. By the way these devoted Chevy fans didn’t have the kauhunas to tell me about the wire pull but a nice freshman was happy to let me know that he was standing right there when they did it. Needless to say that gave me months of harassment time with them.

I got to them again a couple of years later at a local 1/8th mile drag strip. I was quicker than their lovely 1969 SS Camaro and Chevelle even though the wheel hop on my car was terrible. The guy in the timing tower said it hopped so hard that he could see the seal on the trunk to body actually separate. I took it upon myself to take their best times and mine and make a nice wall plaque. Over the years I have seen it removed from my wall in my computer room after they stop over.

Any way you look at Pontiac was a TOP player in the performance world and can and could keep up with anything. When I saw the front end of a 1968 GTO I was for ever changed and I wish I still had my 69 Judge Jacket but I wore it to rags many a year ago.

Almost ALL pushrod engines are non-adjustable
today. Tried to adjust a newer big block GM?
How bout a GEN3[5.7.4.8,5.3,6.0,etc],3.1,3.8
any later model mopar or Ford? They`re easier in the field just to slap back together.<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by silver:
Along with the many great design ideas Pontiac had there are a couple elements that seem like they could have been improved;

The water passage between the back of the timing cover and the front of the intake manifold. Pulling the intake towards the timing cover with that slender bolt can alter the alignment of the ports in the heads to the intake. Although sawing off the front of the intake solves this and allows for a dry intake swap...I would have prefered a short section of hose ala Olds or BBC.

Non adjustable valve train - decking the block or shaving the heads can really foul this up if you're sticking with the factory system. I guess it's easy enough to convert the heads to an adjustable system, just kind of a puzzlement why the non-adjustable design was held to.

Out of curiosity, which other major Engine designs used a non-adjustable valve train? Was it more economical to build on the assembly line? Was it less prone to problems for the duration of the warranty? <HR></BLOCKQUOTE>

Most everything has been mentioned but, there are still more. Tom mentioned about not having to pull the dist to do an intake swap but, it is even better than that. You can pull both heads, change rod bearings or more and not have to touch the dist/mag. Having the starter on the left has proven to be an advantage as some chebs have switched to a left side starter for an oil pan kickout on the right side. What about the rocker baffles? I have seen them in the Bill Mitchell catalog for chebs as a "new idea"!.
I like the motor mounts, the Pontiacs have the nut welded on, the cheb guys have the fuel pump in the way and have to hold a nut while they turn the bolt. There are so many little things like that that make a Pontiac more pleasurable to work on.
As to Pontiac engine production and the corporate thing. Believe it or not, it actually started in 1959! That is the last year that GMC trucks with the V-8 option used Pontiac power. I read that, though GMC customers were happy with Pontiac touque under their truck hoods, the Pontiac engine plant wasn't able to keep up with production for both cars and trucks so they dropped GMC and let cheb use their V-8s. Imagine how many HD 4bolt truck blocks and forged cranks and rods there would be today if Pontiac still supplied engines for GMC!
Steve www.pontiacheaven.org

Quote:

"Having the starter on the left has proven to be an advantage as some chebs have switched to a left side starter for an oil pan kickout on the right side."

Thanks Steve! I knew about the left starter/ right oil pan kickout as the aluminum pan from the Hamberger people I have is built with the kick-out and does a great job.

The round holes in the block deck surface make it very easy to make a "Dry Deck" engine with normal cast iron
plugs.

You can feed water externally into the block easily if
you weld a fitting into each of the core plugs in the three locations on the late blocks and make a water manifold.

The front of the Pontiac block is flat in the timing cover area which makes easy mounting of a front engine plate, external water pump, dry sump, and/or a front
mounted distributor (like the BOP unit).

Tom V.