I have a buddy who loves these motors, always tells me how great potental they have, anyone run one? just curious?
i've got one out of a 72 gto in my wifes 67 firebird.if it werent for the leaky q-jet and hiway gears in the rear it would be a real puller.
buddy of mine at the local speed shop has a 68 firebird with a poncho 400 in it. it still pulls damn good with the little 2 barrel on it too! fun little car!
Great motors with plenty of cohones but as Brandonsgrandpa stated better run a rev limiter. Have built many and been pleased with most.
I've had several. Lots of torque, and strong runners. Just understand that they aren't 283 Chevies, and don't try for 7000 rpm. I've seen mid '70s T/As run in the 12s with 3.08 gears---from 0-5000 rpm, they're monsters.
can they still be had at the junkyards fairly cheap? what aout speed parts? Sounds like this might work for a project of mine, decent power and affordable motor? trany options? speed parts? how do i identify one?
i run one in my 67 Tempest---- a great mill it is.... bop-pattern th350 or th400 tranny (or th200r) all work fine.... to id them there is a stamping on the rear of the block, towards the top on what would be the passenger side.... they are still out there but becoming harder to find (at least around here)..... I built mine for under 1500 bux and it has about 400hp and 460 ft/lbs at the rear wheels..... Yeah, they don't like to rev much past 5200-5400 rpm.... The valvetrain is the weak link in these motors... but a BB chevy valve train is an easy swap..... Try and find a set of 4x or 6x heads... and stay away from the 74 and up motors (smog motors) unless you are gonna rebuild the entire motor and throw a bunch of parts at it.... A lot of parts available for these mills, all pontiac mills have identical dimensions except the 389 and pre-63's(?)... so everything is pretty much interchangable.... (I still tell people that my car is a 326 car) (oops cat is out of the bag) The bottom ends are virtually indestructable......even in stock form..... I have run a 200 shot of giggle junkwith no probs, just changed the jetting in the carb and pulled some timing out..... And you can get a tri-power intake if you wanna make it pretty...... I could rant on on for ever about pontiac motors..... Oh, wait..... I am.......
I Ve Ran Pontiacs For 25 Years+ Sold On Torque And Hp. Very Reliable !!!! Building A Poncho Powered 59 Chassis Research Dragster Now Anyone Out There Near Mich Have A 55-60 Pontiac Motor For Sale??? Looking For Block Or Complete Thanx Jerry
Here's mine this morning. Started making a funny noise at the drags friday night... I have the wierdest shit happen to me, I swear..My shop truck has the same 421 I built 13 years ago, yet my hot rod goes through cams, blocks, etc every couple of years.. Don't let me scare you...Pontiacs are bitchn motors. Holler if you need any help. -Abone.
I've got an apart but complete '73 Pontiac 400 from a LeMans "Grand Am" I'd sell for $100 if someone comes and picks it up. That's a steal, I need the space.
I am running a '65 389, 40 over in my A coupe. I have several buddies that run Poncho's as well. Great motors, super low end torque.
Don't feel bad if you can't find any '67-'72 performance heads; even the "smog" 4X and 6X heads can make good street power. While they aren't as easy to find as they were a few years ago, it shouldn't be that difficult to locate a garden variety 400 out of a Catalina or Bonneville. I see Edelbrock Performer intakes for Pontiacs at every swap meet I go to, along with countless pairs of headers--I probably saw at least a dozen sets at Englishtown on Friday. Flywheels are out there at the meets as well, and B-O-P stick bell housings are still pretty much falling out of trees. They have a two letter code (YH, WT, etc.) in the same place as small block Chevies do--on the passenger side front. Pre-'70 blocks have two motor mount bosses and '70-up blocks have three, but adapter brackets are available if you need them for your particular chassis, and some blocks had all five bosses.
So when i got to the junkyard this week im gonna look, they came in late 60's early 70's big ponchos? Since they are all the same easiet way to tell its a 400 is the numbers?
well, my buddy has offered to help me put one together if i can find a shortblock, hes got a tranny, and some other stuff for me and maybe a set of heads, anyone got one they wanna sell?
I have some 4x heads laying around. I picked up the 400 for the connecting rods they are the same as early olds. Anyone have some early olds speed parts and want to trade?
They're good motors. Had one in a '70 Gran Prix as a kid. Not a good idea, I did 100 in it several times. The most amusing story was when they oiled one of the side roads in the spring. I come up to a stop and they'd just done the lane I had to cross to turn left, so I layed on it and left two streaks that were there until the next time they oiled it again. Even my 389 in my '60 Pontiac would really go, I never had a problem with it. I have a spare '59 389 I'd let go of if someone wants. I got a '77 400 last winter for $200, and we got a '68 that was set up but pretty clean inside for free a while back. the whole car for free. I even had 3 455's at once and paid like $2300 between the three cars.
I've got some earily 70's 6X heads laying around. Local guy told me those are the heads to have, but he says that about lots of things. Are they worth a darn? Is it worth my time to clean them up and sell'em? Just curious.
There are two kinds of 6x heads, 6x-4 and 6x-8 The 4's have a higher compression ratio and are a bit more valueable. I used 6x-8 heads on my 455 with a bit of meat shaved off of them. Check eBay, 6x heads do sell.
6x's are not that big of a deal.there are a ton of them around.a better head that is still easy to find sometimes are the # 13's & 16's.toss a set on a 400 and it will be a runner.some are saying run a rev limiter.?I've turned mine to 7200RPM a few times with just a set of stock rods with the side beams polished.still nice to have a limiter though.? in case you don't know how to shift when the neddle goes in the red.???
I had pontiac motors to 6500 to 7000 rpms also. My results were usually like post # 14 or worse.Most of the time the heads can be saved.If you are real serious about racing them, a oil filter eleminator is another good devise. AND NEVER use a high pressure/volume oil pump. My first pontiac motor was a 55 in a 32 ford pu. another bit of advise is...If you are TALL.chopping/sectioning/channeling should be well thought out. I wish i had made a notch on something to have record the # of pontiac motors I ruined.But who gives a shit. It has been BIG FUN!!!!!!! Jim
Anybody else ever have a Chevydude argue with them that the Pontiac 400 is in fact a Chevrolet 400? Talk about making me want to throw punches!
...and if you want big valve heads with lower compression for the piss known as pump gas today, look for 96 or 7K3. Between the two, the 96 heads are preferred, because they were the last ones with six exhaust manifold bolts. Headers have enough leakage problems without going down to four hold down bolts.
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