SPUN ROD BEARINGS! Especially when using a solid flat tappet cam. The sore spot with all Pontiac V8 engines is the stock rod bolts, not the rods. On any rebuild, you must replace the stock rod bolts with ARP bolts and resize the big end of the stock malleable iron rods. That will cost about $200 - $250 per set. Now there are economical aftermarket (Eagle) steel rods for Pontiac V8 engines and only cost a little more than resizing your old stock rods. There is nothing wrong with stock cast ductile iron rods if the bolts are replaced with ARP bolts, especially in a 389/400 engine. The 421/428/455 engines needs aftermarket rods rather than rebuilt stock rods if you are going to thrash those engines. . The Pontiac rod bolts are the cause of rod failures. They stretch, cause the big end to go out of round, the bearings spin-out, seize on the crank and the rod snaps just below the pin eye. Then the old cast iron Pontiac rod gets the blame for the failure. I have shifted a 400 CI Pontiac with stock rods with ARP bolts at 6500 RPM many times with no failures. Stock Pontiac rod bolts are spongy when you torque them down to 46 lb (and not a ounce more) and will break between 60 and 70 lb. torque. ARP bolts come up to torque rather quickly and will not break even at 90 lb torque. If you try to drive a Pontiac like a SB Chevrolet, expect spun rod bearings unless you have resized the rods with ARP bolts. The 1973-1979 stock Pontiac rods are better because they have no spit-hole to sling oil on the camshaft. With no spit-hole, your crank oil passages will force more oil across the face of the bearings where it is needed most. Enlarge and re-chamfer the three center mail bearing oil feed holes to 5/16" in the upper half of the main barings to match the holes in the block for more oil supply to the rod bearings. Besides paying special attention to the oiling, replaceing the bolts and resizing (or replacing) the rods, a Pontiac engine is a very reliable racing engine. In a short wheel-base and light weight vehicle such as a '26 Ford T, never push a torque monster like a Pontiac engine to it's limit or you may be upside down in a ditch.
we run a 455 HO in our 62 chevy PU and love it. Kouffman Raceing makes all the go fast parts for Pontiac also. some of the racers we run with that have Pontiac motors run 308 and 336 gears because of the low end torque, and still get 16 mpg's on the hiway.
Go buy the Jim Hamd book. It's Poncho performance bible. http://www.amazon.com/How-Build-Performance-Pontiac-Design/dp/1884089674
I have a 455 Pontiac (of course) in my 67 GTO, and am putting one in my '28 Pontiac. The motor is kinda heavy and wide. The newer blocks have serveral provisions to mount motor mounts so you would have some options Bruce
great input Duntov.......also on my 63 motor the studs were changed to screw in, oiling now flows through pushrods. restricted oil flow to top end with special lifters. running a rev chip set a 6K, light car dont need to wing any higher .
Mr Haney what trans are you running in your 30? That is one good looking ride. Have you ever had it to the strip?
In 1961, my associate had a 1959 389 CI Pontiac tri-power engine in a fiberglass '27 T bucket roadster which was channelled over 19?? Ford frame rails with a transverse spring in back. It had a 40" fiberglass truck bed containing a Moon gas tank. He could punch that thing at 60 MPH and with some good bite, he would lift the front tires 3" off the pavement. At 90 MPH, I looked down at the right front tire and it was just skipping along hitting the high-spots of the pavement. He had a B-W 4-speed transmission in it and it would smoke the rear tires and go sideways in 2nd gear from a dead stop. He never used 1st gear because it was just like a granny-low. It was equipped with a 1940 Ford rear end with 4.44 rear gears. The roadster was pleasing to look at even with no chrome and it was still in the fiberglass black gelcoat. It would be what we call a "rat rod" today. Back then, I called it a "death trap." It had no roll cage and no seat belt harnesses. We drove around in it for 6 months with no windshield because reproduction windshield posts were on order and were being made at the time. He finally got them and built a frame and windshield with struts. I think that rat-rod roadster is still alive and kicking today but with a SB Chevy engine. Some things never change.
Thanks for the compliment. I run a 1967 munci close ratio trans with weber aluminum flywheel, super duty bellhousing. car has never seen a dragstrip, new build as of late last season. Plan on racing it at 42 in July [rock and race] Best, Russ
I have a Pontiac 400 that I'm saving for a project. I'd love to put it in a 56 F-100 if one were to find its way to my shop. I've also thought of putting it into a '57 Ford Custom or Ranchero. The Ponchos pictured in this thread are beautiful motors. Rob
I would use it in a heartbeat. Im a big fan of pontiac mills. We have a 55 GMC with a 287 a 69 fire bird350 auto and i have a 68 400 engine that i plan on swapping into my 55 chev two dr wagon . Tri power intakes are plentiful and would look great on your car. OldWolf
Okay, so with a little rearranging I ended up with a different pontiac motor than the one I intended to use, but I scribbled down every number i could read on it. A034.......... 0014843-4.......... K125.......Firing Order 8436572.........525353.......QM1.......4x?......481988.... Can someone make sense of this?
It sounds like a 1974 engine . The 4X heads were 1973-1974 heads. But it also has a K125 number? Was this on the intake or block? And the A024 number Im assuming that is on the heads? These 4 digits represent the Month, day year. A would be January, the next two digits would be day so it would be the 2nd of January, and the last digit would be the year. So January 2nd, 1974. There will be a stamp also on the block at the front passenger side just below the head like a YH, or WX,WZ,WT etc etc. Whet is this umber and then look by the distributer for the same date pad with the 4 digits. Get back with us on that. With Pontiacs, Most blocks are created equal except for a few 1975 blocks , they have thin webs around the crank. To make power its as simple as changing heads and a cam. This is a video of a 2bbl 1968 block with stock cast rods, non ported #16 heads and just a bunch of bolt on stuff like the 4 bbl intake. The block and heads are essentially stock but with TRW stock replacement forged pistons. The first clip is my car in the movies. My car comes in just after the Character "Steve" arrives at his parents house. The second clip is how it idles and revs. Gotta love Pontiacs!! Who said Pontiacs dont rev? LOL! Oh and the video is without the nitrous. That would ad an extra 150 HP. http://www.youtube.com/watch?v=6dTfMAH9UL8&feature=channel http://www.youtube.com/watch?v=Xuq-3a0AHEU&feature=channel_page
bastards. I just spent an hour watching poncho burnouts on youtube. I think I'm gonna go drool over the 400 I have for my 41 chevy now... I've never been disappointed with pontiac power. ever.
If you looked at my videos, my car at 3810 does 12.56 mph with non ported stock 400 heads and a mild cam. The engine cost $999 to rebuild in 1991. If you want power for cheap, Pontiacs fit the bill no matter what most people have heard. You can buy a ballanced rotating assembly now with all high grade parts for $1600. This includes bearings, rings, Ross custom forged pistons, H beam rods, Eagle crank, and ballanced. This will turn any 400 block into a 467 cid engine. If you then install a small roller cam and out of the box Edelbrock heads, try 530 hp and 578 ft lbs of torque on pump gas. The options are endless now with Pontiacs!!! Just look what my 400 does and add at least another 100+hp. Have fun with your Poncho. Oh and there are no big block or small block Pontiacs. On the outside, there are no differences in size and most all parts interchange.
Cool stuff. if you are running a hoodless car, the cool thing is that the design of the Pontiac castings "look" older. I used to hate it when I had a '76 T/A- just didn't seem to fit the rest of the car, but from a "traditionalist" standpoint, you can't go wrong. That design has been around since about 1955 (correct me if I'm wrong). It's also impressive looking because it has a wide stance between the cyl heads. Some metallic paint, detailing, and a set of Cal Custom type finned valve covers and that's boner material.(see page 1 ) What everyone here is saying about torque- OMG. My motor was a 455, with all matched mid range performance mods and 2.11/1.77 heads. That MF'er snapped about half of the wheel studs on the rear axle from 1-2 shifts, ate a couple of torque converters, and would make rubber vapor out of a pair of BFG 295/50's. That was with a 2.73 diff and a 3800 lb car..
Pontiac can be very quick and also very reliable. 2 references are- Quick- my '59 389 based engine I built for my digger so far has run 6.77 @ 200mph in the quarter. It is the quickest of all factory block Pontiacs to date. Reliable- the 455HO I built for my GTO in 1999 is still running strong with 173,000 miles on it. It is just starting to use some oil at idle and has had a cam with over .500 lift for that many miles. It also runs cool here in the Az desert and does not leak. They are great motors for most any application. There are many parts available now too for these fine engines. Steve Hosting- 1st annual Pontiac/Buick/Olds Fall Fest Sat Nov 28 Phoenix 12th annual Pontiac Heaven April 8-11 Phoenix www.pontiacheaven.org 8th annual Nostlagic Show and Go! April 10-11 Phoenix www.nostalgicshowandgo.org
Did Pontiac make high performance heads or were all the heads the same more or less? I have a set off a '67 GTO, didn't know if they're special or run of the mill 400 heads. Check out my signature if anybody's interested in a Pontiac 400.
Depends on the number on the middle exhaust port, yes they made a lot of different heads, some better than others. I traded one set for an entire car a few years ago. As for IDing a motor, the casting number on the right rear of the block #1, the date code somewhere near the distributor #2, the stamped engine code on the right front of the block #3 and you can pretty well pin it down. Most of the numbers are google-searchable.
The heads should be 670 heads, close chamber 10.5:1 compression. They are decent performance heads. 2.11 Intake, 1.77 exhaust and have screw in rocker studs.
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