Why is it that pontiac 350's are considered Big Blocks and Chevy 350's are considered Small Blocks? I might just be missinformed but I have heard something about this in the past.
Desktop Dyno lists them as such.
Also; are the installs any different on the two different types, any input would be appreciated

 

Pontiac did make a big block with 350 cubic inch displacement and it is totally different than a Chevy 350, but all 3rd Generation F-bodies had the Chevy 350 engine (corporate motor).

 

More correctly, Pontiac had a different engine altogether, not a big block OR a small block. Just 1 block (physically, it was about the same size as Chevy's big block) but the same block covered ALL the dispacements from the original 287 in 1955, all the way up to the 455 Super Duty in 1973. The last genuine Pontiac block was cast for the 1979 model year. (yes, purists, the same basic design carried on through 1981 with the 301, but that was considered the short deck, and had very little in common with the other engine series)

Ok, that being said, all the different GM divisions had their own engine series, most of them being faaaarrrrrr more superior than the Chevy. Then in 1980, we saw the beginning of the "corporate" engine which was the Chevy small block, because it was the cheapest to produce.

There are several companies out there that ARE using the original molds, or improved copies of these fine engines (Pontiac ones, that is!!) and most are being cast in aluminum!!!

Hth

 

Hey Poncho, do you have any links to any of these places that are molding original blocks out of aluminum.

 

i wouldnt be to sure about the FAAAAAAAAAAR superior thing, the chevy small block is not too bad at all, the whole rod/stroke ratio on the pontiac 455s sucked, the buick motors were physically HUGE, similar with the oldsmobiles. also there is a huge lack of aftermarket for the b.o.p. stuff, all in all, id say if cubic inches are a must, the bbc is probably the best way to go. canted valves rock.

adam

 

Poncho is right, no big/small blocks. Same engine size with different bore and stroke. 400's have 3 inch mains where 455 have 3 1/4". The Chevy is cheaper to build but more and more aftermarket parts are becoming available for Pontiacs. And when it comes to torque... Pontiac is king.

 

Try some of these guys:

http://www.jbp-pontiac.com/products.html

http://www.angelfire.com/fl4/pontiac...chineshop.html

http://www.boyleworks.com/ta400/musclecar.html

http://www.wallaceracing.com/index.htm

Lots and lots and lots of good info here!

Good luck! Remember, like bob8748 said, "When it comes to torque... Pontiac is king" If you look at engine specs for even just stock configurations, the torque is huge compared to the Chevy of the same displacement. The engines were pretty much bulletproof. Very hard to break!!! (I know, I've tried!!) But they're also heavier, so it's a trade-off.

As far as the install is concerned, if you have a mid-70's block, they usually have 5 holes for different mount configurations. One of those will work with Chevy big-block engine mounts to put it into the car.

The engine itself will install just like any other, but you might have a tranny issue. The Chevy bolt pattern was different from the Buick-Olds-Pontiac (BOP) standard throughout the rest of GM, therefore, either use a different transmission altogether, or get an adapter plate. Buddy of mine put a built TH200C (IIRC) behind his built Poncho 400 (putting out over 500 hp!!) and it was just fine, even had 4 gears! All this was in a 68 Firebird convertible (gorgeous, btw) and looked totally stock.

You might be looking at driveshaft length and torque arm mounting issues as well.

I guess the bottom line is this... If you were looking for a "bolt-in" to put a real Pontiac motor in your Pontiac car, it won't work. It WILL require some thought, planning, and possibly some modification and fabrication. BUT, it is a very worthwhile project, and the difference in power is amazing, if you don't have subframe connectors, you WILL break your car the first time you really get on it!!

Hope this helps, and good luck!!

 

you missed a Poncho engine site: www.pontiacpower.com

Car Craft reviewed one of their engines, and it looks like these guys know what they're doing with Ponchos.

 

Yeah! There's probably quite a few I've missed! I just copied the ones I happened to have bookmarked that were easy to find!

I tell ya, I can break a Chevy engine, it's not that hard to do, the Pontiac's though, totally different story!! Those things are practically bulletproof!! (same with the other thick-webbed engines, Buick, Olds, Caddy, etc.)

I'm STILL toying with the idea of putting a 400/428 into my T/A, but I don't think the body/frame will handle that much torque without putting in a full cage!

Enjoy!

 

Better off with late sixties to early seventies blocks... stronger webbing. There is a lot of choices with the Ponchos because of the same engine size. I believe you can put a 428 crank into 400 block to build a 440. Bore the 455 to a 467. Hope I got my figures right... (Crown Royal).

 

Not to put down the pontiac engines, but; I believe that all the torque that everyone is talking about comes from the TPI set up, which is famous for having gobbs of torque...granted, most pontiac engines I have seen or read about have a very imppressivve amount of torque. But I think the torque most people are refering to is from a TPI intake. Just my $0.2.

 

Ahem... 87
I was referring to the older blocks. Carbed engines. Every stock car off the production line can run the best TPI system. They are good for daily drivers. We are talking about torque that can twist these late models apart. And yep. Need SFC's and a cage if done right

 

I agree with everything you said, except one...I think that a TPI engine (not necesarilly stock or GM) is just as good, if not better, than a carbed engine when it comes to torque. Now don't get me wrong, you can get amazing power from carbed engines but, I think that if the same time and attention to detail is used when building a custom TPI set up the end product is as good or better than a carbed engine. I am also talking drivability, gas milage, power band, torque. I think it is fare to say that it doesn't matter what kind of engine you build (Ford, GM, Dodge/ BB, SB), if its done right and taken care of you'll get a long life and tons of power out of it. But as far as torque is conserned; TPI engines usually have more torque than HP. Again, not an expert opinion but an opinion none the less.

 

Pontiac motors have no more or less torque than any other motor of the same displacement and compression. The gasoline molecules do not take a break during their release of energy and romantically and sentimentally step outside the cylinder and read the brand name on the castings, and somehow react to the cast iron's owner's feelings for the cast iron manufacturer.

Torque is directly proportional to the cylinder fill (determined by the induction system); the displacement (duh); and the engine's "thermal efficiency", its ability to extract chemical energy from gasoline molecules and turn it into mechanical energy, which is primarily a function of compression ratio. Horsepower is the time rate of torque, and is directly proportional to induction system flow and "thermal efficiency", and little else, as long as the moving parts of the engine can survive at the RPM required for an engine of any given displacement to reach the flow capacity of its induction system.

I always have to laugh when I see people characterize engines that way. "Oh yeah, well my Hupmobile 400 is a 'torque monster' compared to your ****** 400" yeah right.

If you look at dyno graphs or other raw numbers (numbers, like gasoline molecules, are also not sentimental or romantic, and also don't read brand names on cast iron) you'll find that for motors of different mfrs with similar induction systems (intake cross section, port volume, valve size, cam profile, etc. etc.) the torque vs RPM curves are very, very close. Personally I see no reason whatsoever to accept a 200-lb weight penalty in one of these cars, just for the sake of having my "favorite brand" of cast iron under the hood.

And yes, I have a soft spot in my heart for Pontiacs also, starting with my first car which was a 59 Catalina; I also had a 64 Catalina (what a POS), a 67 Lemans, and a handful of others. My fondness for my first car does not cause me to hallucinate about the engine's output however.

 

One point, A heavier rotating mass has the potential to increase torque vs hp. Look at a flywheel for example....

I will second the fact that a poncho mill is a torque beast

 

No kidding, Poncho mills are torque kings. I'm looking into a 400+ci EFI Poncho mill for my car

 

Pontiac engines are not "torque kings", any more than any other brand of motor is. Cubic inches are "torque kings"! Any >400 CID motor will produce more torque than a smaller motor would; no matter who cast the metal that contains the inches. A 400 Chevrolet or a 400 Olds motor will produce esentially the same torque as a Pontiac, given the same cam, same intake, etc.

This business about "my favorite brand" of engine being a "torque monster" is just plain ludicrous. It has no foundation in the real world.

 

You seem like a cool guy but I dont agree with that. For example, a ford engine with the same spec cam etc will make different power than a sbc. THat is a fact. Look at the head ports and other things. You are saying that a 400sbc and a 400 sbf would produce the same power in the same spots? I don't think so. Ford spaces the exhaust ports evenly, this will effect the power output. Hell, I don't even think a small block chevy 400 would produce the same power curve as a big block 400. Maybe more, maybe less but that bb 400 will be different. Different brand names have use different and sometimes rare/expensive casting materials. I also know that a pontiac 400 4 bolt is stronger than a sbc 400 4 bolt....

 

Well the Pontiac vers Chevy has been around a long time. They both have they're good and bad points. As far as the pontiac being tuffer than a chevy is pure And I know where a 73 400 pontiac block is, that still has the center main web atached to the crank. It came out of my race car. It ran 7.80s in the 1/8 when Randy owned it, now it does 7.003 and 8 mph faster with a sbc 383 shifting a 5000 and going thru the traps at 5800. I've had Pontiacs and Chevys AND Mopars for 35 years. For DRAG racing I'll still take the sbc over anything else.

 

this is my 6.6L SBC 87' Formula. I'm proud of my chevy mill...

 

Buick 455 is only 100lbs more than a sbc & has more torque than a 426 HEMI.

Old's and Caddy had the biggest engines as far as size and width goes. I have two old Old's intakes and they are at-least 4 feet wide. My last year 1980 Buick 350x is still considered a small block even though it the size of a BBC. [350r was Chevy]

Reason there isn't as much performance parts for them is they came packed full of performance stock from the factory. They don't need more parts. Where the low buck sbc needs the aftermarket world. Yes Chevy is the ecno line at GM.

TAperformance.com is the place for the good parts.

Running stock for stock motors, a sbc would lose in the GM performance battle. Especially in the 4000+lb cars of days past.

Now the first person to blab how cheap it is to build a sbc better re-think that position. That is why most of the market has jump ship over to ford. They are even cheaper to build and run just as fast or faster, especially in the lighter ford cars.

If cheaper is your only reason, rather then real re-search, you should be driving a ford.

 

damn i feel dumber now that i've read this