Projects 1964 PONTIAC 421 HO Engine Build

Get it running and take me for a ride.

 

Should stuck with a 326 with a lumpy cam. Tell everybody a 421. Visually can't tell. Could of saved a bunch of coin.

 

If you ever take a CA vacation, look me up.

My builder's son has a 421 in a '65 Catalina.

It runs in the 12.80s with a mild hydraulic roller cam and only 9.3:1 compression.

These Pontiacs can run, and they don't need 10.75:1 compression.

 

Yeah, sure.

Any more pearls of wisdom?

 

That would be telling stories.
Having a usable and streetable 421ho isn't going be cheap. The casting and stamped numbers guys will be slobbering.

 

That's a

That's a lie. Big HO Cats were faster than GTOs. Advertising killed the big cars. Had a bone stock '65 2plus2 HO 4 speed that ran 14.40. And a not so stock 67 2plus2 428 HO conv. 4speed ran 13.80. The 67 car weight 4200. And I know where the car is now. Full resto. Still peel the tires off.

 

They do run.
Plenty of poncho blood in my veins,
63 GP
68 bonneville 428 ho
66 Gto tri-power 4 speed
67 firebird 400
68 GP 428
Bunch of parts cars and donors.

 

Not too impressive when my low-compression 455 with 2.56 gears runs in the 13.80s, with no traction tires or posi.

Try again.

Or don't.

 

That GTO i had would do the best burnouts ever - spin the tires straight thru 4 gears till you let off the gas.
Back in 1985 I let loose in a parking lot and it was about 350 feet, all 4 gears with 3 breaks in the shifts. Smoke everywhere and thick. now Every 5 years or so, I see one of the guys who was there that night and that's all he talks about. He just told me the story last year again. A lasting 30 year impression that old pontiac put on him.

 

Very cool.

 

Ran plenty of Poncho's. '62 GP's, Cats. Same car different trim. 63 GP under construction right now. Not mine, but a 45 year old friend. He's had the car 40 years. And who can count how many '63 to '67 Cats. All big blocks.

 

Big blocks

 

Yeah.

True Pontiac guys never use that term to describe 421, 428 or 455 engines.

Oh well.

 

Was running in the late '70s on crap Dunlops. Forgot to mention, ripped the rear end out. Drum to drum twice. Broke the welds off the housing then snapped the control arms.

 

Old Pontiac guys do.

 

But true Pontiac guys don't, and I know plenty of old ones.

 

421, 428, 455. Big block.

 

No

 

Large journal = 421, 428 and 455.

Same block size as small journal 400 and smaller cube engines.

I'm amused.

 

Lol....how is any Pontiac engine a big block when they are all identical in appearance? Remember....why not just build a 326 and save a bunch of coin?

 

Yer killin' me.

 

Great threads on your Ponchos buddy...wish I still had mine...

 

Thanks, just killing time the best way I know how.

And thanks again for turning me on to that greasy, rusty '59 389.

 

Man, is the engine compartment pretty enough for that jewel to drop yet ? I've watched this the whole time. You're ready to bump the key, while I happily close my eyes to pipe dreams twisting in the wind .... makes a sh#tty wind chime. In any event ... get to ringing a dinging bud !! What a great project.

 

Thanks for the kind words.

It's all pretty, everything's painted inside the engine compartment as well as the frame and front end pieces.

Just need to straighten out a few things here at the house before I can have room to do the transplant.

Soon.

 

Try droppin' a 326,347,350,380,400 crank in a 421 block and see how that's gonna' work. It only works in reverse if you cut the mains down. Old one from the 60's. Turn down a 421 SD crank to fit a 389, then punch it 90 to 120 over.

 

Boy did you bring back memories man. I purchased a 64 421 HO Bonneville convert in 67 for $1600. Since the vacuum linkage for the outside carbs did not work all the time I had a Pontiac mechanic install mechanical linage and a fuel block at the same time. In 69 after paying off the bank loan I had took my baby to Hi-Speed Power Equipment in Valley Stream, L.I., N.Y. to have the engine blueprinted to factory specs. The engine was pulled, bored .020 over for the chrome molly rings, crank magnaflexed and balanced, new oem cam and lifters, Rochester carbs rebuilt, etc. for $2,000. The engine was reassembled and tuned on Frank Dominianni`s Stranguellini engine dyno. Frank was a Corvette specialist and National class B sports car champion in 62. He new how to tune engines with Rochester carbs and one of the few people who knew how to tune the old Dontov fuel injected Vets. I believe my 64 421 HO had the aluminum case 4 speed Muncie tranny same as the 427 Vets. with the 2:20 1st gear. I also believe it had a heavy duty 4:10 not a 4:11 rear. Please correct me if I am wrong, it was a long time ago. I took it to National Speedway on the Island and because of the fuel block and mechanical linkage they put me into a Modified class so I did not expect to win running stock exhaust and standard street tires. I did turn 13.9 @103.5 mph turning 6300 rpm going through the traps. Not bad for a 4300 lb. Bonneville convert in mho. That car was one of my 3 favorite cars I have ever owned. The others being the original 89 Taurus SHO and my 07 Spec. B.

 

Glad you enjoyed the thread.

Running in the high-13s is pretty darned nice for a heavy convertible. Twisting that 421 up to 6300 is about 1000 RPM past peak HP point, 5200 RPM is about where the stock HO cam and cylinders heads call it quits.

I'm betting your car would've run just as quick with 3.42 gears out back as opposed to the 4.10 gears, these engines are torque monsters and really don't need to be geared like a small-block Chevy.

I mentioned earlier here where I daily drove a very mild 8.2:1 455 with the same HO cam and a TH400 trans with 2.56 gears, it ran 13.80s at nearly 102 MPH.

Torque.

Maybe there's another Pontiac in your future.

 

I'm really liking the wheels too. Great job.

 

I also have another set of period-correct wheels I will be using too, to change up the personality of the car from time to time. I sold the thin triple-stripe whitewalls, I will also run narrow whitewalls with these.