draggin GTO that is some great info you have been posting. Thanks for taking all the time it takes to host the photos etc. Now if we could FIND some of those heads to use................
Pretty much any 59-up mount will bolt to any block, even the late 301 3-bolt mounts will physically bolt to a '59 block using the two end holes. But for the second-generation Firebird/T-A they moved the position of the mount on the block, resulting in motors that usually have pads for both but they aren't always drilled and tapped. I suspect it depends on what block casting # as to what mount provisions it has. So your buckets will work but might not be positioned right if your clip is out of a second-gen F-body. Here, depending on the year you might be able to move the chassis side of the mount to get something that will work, since these could be had with a bunch of different motors over the years.
I'm using a '74 400 block. Are the holes different than '78? I was mainly checking to make sure the bucket heights are the same. I know that from my CHevy experience, some cars had different height buckets.
Be sure to check for valve to cylinder/piston clearance. My first car was(is still) a '64 GTO with a 389. Back in the late '60's, a fellow Pontiac hotrodder said that I could get more horsepower with the '65 389/421 heads BUT I would have to have the block "eyebrowed" at the edges of the cylinder bores so that the valves would not hit the block. I am not sure about this because I never swapped the heads and I can't swear that the information is correct. The '64 389 heads supposedly had smaller valves than the '65 389 heads and maybe all of the 421 heads. Just be sure to check this out to see what will work and what won't.
Somewhere in the mid 60's Pontiac changed the valve angle. But, that's prolly been covered here in prior pages
May I add that my big-headed B-i-L bought a used STOCK '67 'Bird with a 400/4-speed in it back say in '71 or so and like 1 year later, the front aluminum water pump/timing chain housing corroded through and put coolant in his oil! Luckily he caught it before toasting the motor! Please check this close! pdq67
Just found this thread thanks all for the great info. I've got a question and excuse me if its already been covered but what manual car 4 speed trany interchanges with a 1957 347 truck motor? Right now I have a creeper truck 4 speed. Any help would be great thanks .
Most current replacement pistons for Pontiac engines are made with reliefs for both valve angles. At least the ones I put in the 389 I did, had two sets in the tops of them.
Hey Super Poncho Tech Gurus.... I needed to replace some rocker arms in my 55 287, (A couple are sitting on an angle) Any suggestions on what will fit that might be easy to find, or is it 55 only? Also half the rockers aren't getting oil, is this serious trouble? any suggestions on how to fix this without tearin the heads or motor down? Thanks!
I didn't notice anything about "Best Valve Covers". In my quest to build a nice street and 'test & tune' 400, I bought a few sets of valve covers. Once again, and no suprise, the stock Pontiac part is the first place to look. Some stock stamped sheet metal covers have spot welded sheet metal drip guides to direct the oil squirting out of the push rods down into the rocker fucrum. This is no small issue. Too bad those Mickey Thompson covers don't have that. Those Offenhauser covers look the best! Too bad they don't have it either! I'm thinking about making oil guides from 6061 aluminum angle and TIG welding them in there, because if Pontiac thought it was a good idea, then it must be worth while.
Just ran across this thread...very cool. I noticed in the very first post it was said that the Super Duty came along in late 1961...It has ben hashed around before but the 421 did not start the Super Duty program...Super Duty was introduced in to selected people in 1960...a whole lot to the NASCAR boys but was also around for the drag boys...I do believe the first factory built SD car's came in late 61..I had & sold as set of 60 Super Duty heads several years ago. You had to use a corresponding intake with it. The valve geometry was different and I believe stem length was like a .100 longer and the shape of runners was different too. I also had a "510" aluminum Tri-power intake which was cast like a 61 but was declared illegal for 61 but legal for 60's by NHRA ??? WE used to plug the water by pass hole.. I presently run a NSS 60 the Arapaho but the motor is nowhere near a old 389 !! Ran a 10.28 @ 133.90 & race weight is 4,090..Still more left in it.. Later..
People tend to associate the SD program with just the super duty 421, but of course the SD389 came first. It was an over the counter engine only, available from 1960 to 1962. As far as the SD421 goes, the general consensus is there were a handful of engines delivered very late in the 1961 model year to selected racers (Thompson, Beswick, etc.) but none were installed in a car at the factory - that didn't happen until 1962, and that lasted until the GM racing ban came down in 1963.
Beswick's '61 was delivered with the Super Duty parts for the 389 in the trunk to be installed at the dealership. He drove the car down to the Winternationals and installed the McKellar cam in the parking lot of the Hotel that they were staying at.
hi Big Cheif i read what you wrote about putting sbc studs and rockers on 55-60? pontiac engine post 142.i have everyting on shelf is it sbc 1.5 rockers you mentioned long shot.and for pushrod lenght did you use sbc or pontiac. im a swede so explain the word fulcom iwas not in dictiornary. ken
Here's a page with a simple drawing showing a rocker arm fulcrum. A fulcrum is a physics term regarding the pivot point of a lever. http://www.autozone.com/autozone/re...wTo&pageId= 0996b43f80a0118d&subtitle=inspect http://www.stevesnovasite.com/forums/showpost.php?p=1488102&postcount=9 We almost always use custom length pushrods in our builds so I'm not sure what the exact length was, it was most likely closer to the Pontiac 9.1" pushrod than the SBC 7.8" pushrod. You'll need to check the valvetrain geometry to see exactly what length pushrods you'll need.
Its BB Chevy studs and Small block Ford Rockers that will work. Not SB Chevy Rockers. Theres no way they will work.
pontiac .chevy bb.chevy sb use the same 7/16 studs if you have solid lifters or in high lift cams.for the eye all rockers look the same.i dont want to invent the wheel again.pontiac have a oil problem 1955-1964 with rockers wearing out mostly from bad oil supply tru block and heads.by putting oil tru rockes this will be solved. thanks for info about pushrods BIG CHIEF.i have to ask i was to easy using stock lenght. ken
Thats what I run, bbc 7/16 studs and sbf 1.6 rockers. But the pushrod hole must be elongated for any higher ratio arm.
I run BB Chev studs and 1.65s on my engines that could stand a little more lift and it also adds about 3-4 degrees duration. My Stock rebuilt 400 that was built in 1991 is still running strong and pulls 1.6secs 0-60ft and 12.5s in the quarter with non ported heads with 44 year old valves "but elonged pushrod holes" on pump gas. It's also in a 3810 lb race weight car. Very streetable. This is why I love Pontiacs. I actually have had 5 at once but am now down to 4 with some coming and going in the 35 years I have been into them. I actually lived breathed and dreamed Pontiacs for about 25 years but they were GTO's and Firebirds 1967,68,69s and then al hell broke loose and Hotrods got into my blood so I'm changing a bit to learn about Hemi powered Whippets and 351 Fords in a 1936 Ford right now in my life. Still have my love for Pontiacs but....... a little diversion.
Sounds like you got a nice 400 combo going there. What cam, stall and rear gear? I'm still working on mine to get there, changing stall and ring gear this winter.
I'm running stock #16 heads, an old Crane Commander that is close to the same specs as the Summit 2802 or the Edelbrock Torker Plus. 224-234 on 114 degree lobe separation. Tight 3,000 stall. The 2400 stall also worked but at the track I could feel it needed a bit more. 3:73 gears with 28" tall Mickey Thompson Drag radials. These don't stand a chance on the steet for hooking up!!! Even at 20 mph! My dyno numbers were over 400 HP engine HP and 478 ft lbs at the rear tires from just over 3500 to over 6,000. The graph looked like an arrow!!! Holley 800 DP with Street Dominator , 2 1/2" exhaust with X pipe. I actually added nitrous and am doing 11.7s with a piss poor 150 shot. Pig rich and bouncing off the rev limiter at the 1,000 ft mark. It's actually a real basic engine. The transmission is a $150 used TH 350. I built a car that has a ton of low mid end torque that seems to still make power beyond 6200. I just don't want to take the stock rods up higher than this. Here's a video of the engine getting a bit of a workout. This is how this car gets driven most of the time. Sometimes I feel sorry for it!! LOL!! Watch the movie clip from start to finish. Its not a commercial. and crank up the volume. I think the engine sounds killer. http://www.youtube.com/watch?v=6dTfMAH9UL8&list=UUEINMnZhujPuBIqY-4jHfyw&index=17&feature=plcp The best thing about this combo is that it never gets above 175 degrees even in the heat of the day in stop and go traffic and I burn pump gas. Im actually thinking about yanking all the braided hoses and Nitrous crap off and making everything look stock again complete with stock Rally II rims but still haul ass. It has stock interior. Here's another video of the car. http://www.youtube.com/watch?v=Xuq-3a0AHEU&list=UUEINMnZhujPuBIqY-4jHfyw&index=16&feature=plcp
Im currently doing my first Pontiac. It`s a `71 455 with `70 #13 heads. Going with the factory replacement forged flattops w/ 4 valve reliefs. compression calulator says 11.4 for this combo. The engine was built in the 80`s. Told it was a 2 bolt main block turned into a 4 bolt main and line bored. It has main studs. The cam is around .520 lift. I`m guessing. I took a mesurement of the lobe height and x 1.5. It had one bad pistion, Melted ring landings. Prob due to a lean condition. I have the Holley 750 DP that was ran on it back then and it looks like the jets were never changed. So #72 primary jet (and prob secondary) + 11.4 comp and 455ci....lean. I wanted to do a cheep rebuild and reuse the cast pistions just replace whats needed, but they don`t make the cast STD bore pistion anymore. In fact its damn hard to find anything STD for a 455. Anyway, it`s going in a Datsun 240z racecar with a TH350 and a Chevy 8.5 rear with 3.42 gears. looking for 11.4`s without breaking a sweat. Prob add a 150 shot later down the road. Yeah I know Datsun 240z!!!! OFF Topic!!!!....So what, were talking Pontiacs here! Mark
Dear Pontiac Engine whisperers! I am posting on behalf of my mate who has 62 Catalina! with 389 4 speed that has just landed and is having a problem with the ring gear and starter and was hoping you may be able to assist. The problem is that the nose on the starter is not protruding far enough. it's not completely engaging with the ring gear. It's metal on metal with a terrible grinding sound. the starter then spins too freely and craps out. The gear is left chewed up. They've tried shimming the starter and it just cant be shimmed any further. I'd say it's less than 7 or 8mm away (shops indication) Any part numbers to look at for correct ring gear? It is possible that the T-10 is not the correct one for the year. So maybe there's a difference there. Believes the starter is correct, though it is a newer style one. Any insight Pontiac scholars? Here's a pic of the car..
Does anyone know where I can get a head that will bolt to my 55 v8 pontiac 287? just got the call from the machine shop...engine is perfect..aside from a huge crack in one of the heads. Thanks guys
If I remember correctly you can put some later heads on if you use the correct intake for the heads. Gary
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