I ran across this , thought it was worth looking at
Pontiac 421 V8 Engine
http://www.hotrodtempest.com/Pontiac_vs_Chevy.html
18 reasons why I think Pontiac engines are superior to Chevy's!
As you may have already guessed, I DON'T LIKE CHEVY ENGINES! It's not that I don't like Chevy's, hell, I can respect any make of car except for maybe AMC! It's just that I'M SICK AND TIRED OF BEING TOLD HOW GREAT THE CHEVY ENGINE IS, by those who have never had, or worked on anything else! I fail to understand why they became so popular. One might say that they are popular because they are cheap to build. This can be debated. First off, they had to become popular before aftermarket parts became cheap. Thus coming back to the original question, WHY DID THEY BECOME SO POPULAR? Second, if you are building a bone stock engine, sure, I'll be the first to admit, you cant get any cheaper. But, if you are trying to make some real power, then they no longer are cheaper. You can build a 400-420 H.P. Pontiac for about $1500-$2000. To make a small block Chevy stay together at that kind of power it costs $3000-$4000.
In all my years of working on cars I have found that there are few engines that are harder to make on-the-car repairs than the Chevy engine. I haven't yet found a V-8 that was easier to work on than a Pontiac. For this reason along, you would think that a Pontiac should have been more popular in the racing circuit. The Chevy engine has a LOT of downfalls. Here are some reasons why I think Pontiac's are better engines.
#1: Pontiac had performance on their minds with every V-8 they built in the 60's. Even the so called 'low performance engines'. Example: every engine from 65-68 had a full length windage tray. Even the 2 barrel 326's had them. And from 69-72 they all had a 4/5'ths windage tray. Only the 'ultra high performance' Chevy's had a windage tray, and it was a joke compared to Pontiacs.
#2: Pontiac machined the combustion chambers in thier heads which provided a much smoother surface than a cast chamber like a Chevy. This makes for much more accurate chamber volume, as well as making less 'hot spots' in the chamber.
#3: Pontiac used screw-in-rocker studs on all performance heads from 67-up, and on all heads from 75-up.
#4: Pontiac had some of the largest valves in the industry. 2.11 inch intakes and 1.77 exhaust. Only special high-perf. BB Chevy's with 2.19 intakes and 1.88 exhaust, and Ford 351 Cleveland 4 barrel heads with 2.19 intakes were larger. The 351c engine had 1.71 exhaust valves. Except for really old Pontiac heads, 1.96 intake and 1.66 exhaust valves were the smallest valves used.
#5: Pontiac had the brains enough to put a valley pan cover over the lifter valley. That way the intake manifold didn't have hot oil splashing up on it [another performance thought from them Pontiac engineers]. Also you don't knock dirt into your engine every time you pull the intake off.
#6: Pontiac intake manifolds are so easy to change since you don't have to pull the distributor to change it. Unlike those Chevy's.
#7: Pontiac timing chains are a breeze to change since the balancer, and timing gears come off without the use of pullers. Also installing the timing cover is a breeze since you don't have to loosen up the oil pan [like you do on a Chevy] and break the seal. Chevy balancers and timing gear are pressed on and can take quite a bit if time to remove and replace. I can do the whole timing chain swap on a Pontiac in the time it would take to install the balancer alone on a Chevy.
#8: Pontiac bottom ends are much stouter and beefier than a Chevy. The only weak point and the only thing I feel Pontiac did wrong was they started casting their connecting rods. These cast rods may have been stronger than their old forged rods, but when something goes wrong [like a seized rod bearing] these cast rods tend to break instead of bend. Although I have still seen about 5 blown-up small block Chevy's to every 1 blown-up Pontiac. Put a set of good rods in a Pontiac and you pretty much have a bullet proof bottom end.
#9: Pontiac centered their main caps with dowel pins, Chevy's just snap into a recess in the block and can be moved from side to side. Pontiac main caps go in one place only.
#10: Pontiac heads, although port size is small, out-flow just about any head from .050-.300 lift. And not by just a little, but by as much as 20-25 cfm @ .100 lift. This kind of flow really builds lots of torque. BB Chevy's only outflow Pontiacs at lifts above .300. Their port size is about twice that of a Pontiacs.
#11: Pontiacs build so much low and mid-range power that you don't have to run the crap out of them to make them fast. Pontiacs make all the power you could want under 5500 rpm's.
#12: Pontiac blocks are real hard and last much longer than other engines.
#13: Pontiac uses big, strong, bolts to bolt on the main caps and heads.
#14: Pontiac uses only 20 head bolts instead of 34, and the bolt holes are blind, thus creating much less cylinder distortion compared to Chevy's 'into the water jacket' design. WHAT'S UP WITH THAT! Why on earth would anyone design an engine where you need to seal the head bolt threads in order to keep water from seeping up the bolt threads into the oil! Chevy cylinders distort about 5-10 times more than Pontiac cylinders do when the heads are torqued on! What were those Chevy engineers thinking!
#15: Pontiacs are so much easier to change spark plugs on. No ex. manifold in the way.
#16: Pontiac uses a retainer plate to hold the cam in. Chevy uses the timing cover and timing chain to hold cam in.
#17: Pontiac uses some of the longest rods in the industry. 6.625 inches long center-to-center.
#18: Pontiac did so many things far superior to Chevy's. I could go on all day and use up a lot of space on the net trying to cover them all. I think you get the picture though so I will stop for now until I get the urge to pick on Chevy's again. WHICH WONT TAKE TOO LONG!
For now, lets all keep that Pontiac fire burning bright.
viewtopic.php?f=44&t=4211&hilit=pontiac
I STILL DON'T KNOW WHY CHEVY'S ARE SO DAMN POPULAR!
Pontiac 421 V8 Engine
http://www.hotrodtempest.com/Pontiac_vs_Chevy.html
18 reasons why I think Pontiac engines are superior to Chevy's!
As you may have already guessed, I DON'T LIKE CHEVY ENGINES! It's not that I don't like Chevy's, hell, I can respect any make of car except for maybe AMC! It's just that I'M SICK AND TIRED OF BEING TOLD HOW GREAT THE CHEVY ENGINE IS, by those who have never had, or worked on anything else! I fail to understand why they became so popular. One might say that they are popular because they are cheap to build. This can be debated. First off, they had to become popular before aftermarket parts became cheap. Thus coming back to the original question, WHY DID THEY BECOME SO POPULAR? Second, if you are building a bone stock engine, sure, I'll be the first to admit, you cant get any cheaper. But, if you are trying to make some real power, then they no longer are cheaper. You can build a 400-420 H.P. Pontiac for about $1500-$2000. To make a small block Chevy stay together at that kind of power it costs $3000-$4000.
In all my years of working on cars I have found that there are few engines that are harder to make on-the-car repairs than the Chevy engine. I haven't yet found a V-8 that was easier to work on than a Pontiac. For this reason along, you would think that a Pontiac should have been more popular in the racing circuit. The Chevy engine has a LOT of downfalls. Here are some reasons why I think Pontiac's are better engines.
#1: Pontiac had performance on their minds with every V-8 they built in the 60's. Even the so called 'low performance engines'. Example: every engine from 65-68 had a full length windage tray. Even the 2 barrel 326's had them. And from 69-72 they all had a 4/5'ths windage tray. Only the 'ultra high performance' Chevy's had a windage tray, and it was a joke compared to Pontiacs.
#2: Pontiac machined the combustion chambers in thier heads which provided a much smoother surface than a cast chamber like a Chevy. This makes for much more accurate chamber volume, as well as making less 'hot spots' in the chamber.
#3: Pontiac used screw-in-rocker studs on all performance heads from 67-up, and on all heads from 75-up.
#4: Pontiac had some of the largest valves in the industry. 2.11 inch intakes and 1.77 exhaust. Only special high-perf. BB Chevy's with 2.19 intakes and 1.88 exhaust, and Ford 351 Cleveland 4 barrel heads with 2.19 intakes were larger. The 351c engine had 1.71 exhaust valves. Except for really old Pontiac heads, 1.96 intake and 1.66 exhaust valves were the smallest valves used.
#5: Pontiac had the brains enough to put a valley pan cover over the lifter valley. That way the intake manifold didn't have hot oil splashing up on it [another performance thought from them Pontiac engineers]. Also you don't knock dirt into your engine every time you pull the intake off.
#6: Pontiac intake manifolds are so easy to change since you don't have to pull the distributor to change it. Unlike those Chevy's.
#7: Pontiac timing chains are a breeze to change since the balancer, and timing gears come off without the use of pullers. Also installing the timing cover is a breeze since you don't have to loosen up the oil pan [like you do on a Chevy] and break the seal. Chevy balancers and timing gear are pressed on and can take quite a bit if time to remove and replace. I can do the whole timing chain swap on a Pontiac in the time it would take to install the balancer alone on a Chevy.
#8: Pontiac bottom ends are much stouter and beefier than a Chevy. The only weak point and the only thing I feel Pontiac did wrong was they started casting their connecting rods. These cast rods may have been stronger than their old forged rods, but when something goes wrong [like a seized rod bearing] these cast rods tend to break instead of bend. Although I have still seen about 5 blown-up small block Chevy's to every 1 blown-up Pontiac. Put a set of good rods in a Pontiac and you pretty much have a bullet proof bottom end.
#9: Pontiac centered their main caps with dowel pins, Chevy's just snap into a recess in the block and can be moved from side to side. Pontiac main caps go in one place only.
#10: Pontiac heads, although port size is small, out-flow just about any head from .050-.300 lift. And not by just a little, but by as much as 20-25 cfm @ .100 lift. This kind of flow really builds lots of torque. BB Chevy's only outflow Pontiacs at lifts above .300. Their port size is about twice that of a Pontiacs.
#11: Pontiacs build so much low and mid-range power that you don't have to run the crap out of them to make them fast. Pontiacs make all the power you could want under 5500 rpm's.
#12: Pontiac blocks are real hard and last much longer than other engines.
#13: Pontiac uses big, strong, bolts to bolt on the main caps and heads.
#14: Pontiac uses only 20 head bolts instead of 34, and the bolt holes are blind, thus creating much less cylinder distortion compared to Chevy's 'into the water jacket' design. WHAT'S UP WITH THAT! Why on earth would anyone design an engine where you need to seal the head bolt threads in order to keep water from seeping up the bolt threads into the oil! Chevy cylinders distort about 5-10 times more than Pontiac cylinders do when the heads are torqued on! What were those Chevy engineers thinking!
#15: Pontiacs are so much easier to change spark plugs on. No ex. manifold in the way.
#16: Pontiac uses a retainer plate to hold the cam in. Chevy uses the timing cover and timing chain to hold cam in.
#17: Pontiac uses some of the longest rods in the industry. 6.625 inches long center-to-center.
#18: Pontiac did so many things far superior to Chevy's. I could go on all day and use up a lot of space on the net trying to cover them all. I think you get the picture though so I will stop for now until I get the urge to pick on Chevy's again. WHICH WONT TAKE TOO LONG!
For now, lets all keep that Pontiac fire burning bright.
viewtopic.php?f=44&t=4211&hilit=pontiac
I STILL DON'T KNOW WHY CHEVY'S ARE SO DAMN POPULAR!
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