PY Online Forums - Bringing the Pontiac Hobby Together

PY Online Forums - Bringing the Pontiac Hobby Together (https://forums.maxperformanceinc.com/forums/index.php)
-   THE LOBBY (https://forums.maxperformanceinc.com/forums/forumdisplay.php?f=467)
-   -   Neighbor gave a 350 Engine and TH400 (https://forums.maxperformanceinc.com/forums/showthread.php?t=882147)

Half-Inch Stud 09-12-2025 06:34 PM

Neighbor gave a 350 Engine and TH400
 
1 Attachment(s)
Recently arrived. You know this means i gotta sort it out (complete tear down, clean).
Got no 400 or 455 Blocks ( no intakes or EXH either) to build something.

71 cast date 350 block. heads got screw-in Studs. PC TH400

Half-Inch Stud 09-14-2025 08:26 PM

Update: the TH400 was a 73-BC, Buick, and the internals are good.

The 71 cast 350 is a YP, cast rods, 4-brow valve reliefs look good.
had unported 1969 13's heads ( i can work with that).
Replacement Timing Chain was loose.
Lifters had minor wear, tossed.
Cam seems good, but 0.39" with 1.5:1, 0.43" with 1.65:1.
HEI 1112500 seems good.
Pulleys; Water, crank, AC seem nice enough.

OCMDGTO 09-14-2025 08:34 PM

Stud,
You need to get behind the wheel of another Pontiac

Half-Inch Stud 09-15-2025 08:02 AM

Slow and steady apparently. Desire a large CiD for TQ and towing. 95 Towncar would be the chassis.

Best result is reuse of the Fuel-Inj & coil plates, so 36-1 and probable serpentine for AC, Alt, PS.

77 TRASHCAN 09-15-2025 09:42 PM

Weight of Town Car?

You know what to do to the TH400...

I didn't see any pulleys or brackets on the 350. It could be used to engine mounts and such until a 455 knocks on your door. It'd give you something to do...

Half-Inch Stud 09-16-2025 10:28 PM

Quote:

Originally Posted by 77 TRASHCAN (Post 6582182)
Weight of Town Car?

You know what to do to the TH400...I didn't see any pulleys or brackets on the 350. It could be used to engine mounts and such until a 455 knocks on your door. It'd give you something to do...

Yea, if the 350 CYLs are good, then it will be a build&run for all systems to get done, including cam break-in. 350 had V-grove pulleys, and igot to figure on Vee vs Serpentine due to Towncar AC. Hmm. 400/455 block comes later ( if not sooner like trip over a deal.)

Hunter98TA 09-17-2025 06:37 AM

I have the heads and intake from a 68 400 GTO if you're interested. I'm just over the River in SJ

Half-Inch Stud 09-17-2025 07:57 AM

Quote:

Originally Posted by Hunter98TA (Post 6582418)
I have the heads and intake from a 68 400 GTO if you're interested. I'm just over the River in SJ

Thanks, that would be interesting, but im in north Alabama these days.

Hunter98TA 09-17-2025 08:12 AM

OK, I just ran the numbers on the 2 intakes I have if you're ever back up this way

9790140 Firebird (350HO, 400, 400HO, 400 Ram Air I), GTO

9799068 Firebird (4bbl, RA III), GTO (4bbl)

jhein 09-17-2025 11:04 AM

FYI, Frank's has a few decent 400/455 blocks available.

Half-Inch Stud 09-18-2025 08:01 AM

Quote:

Originally Posted by Hunter98TA (Post 6582427)
OK, I just ran the numbers on the 2 intakes I have if you're ever back up this way

9790140 Firebird (350HO, 400, 400HO, 400 Ram Air I), GTO

9799068 Firebird (4bbl, RA III), GTO (4bbl)


Either 0140 or 068 intake would be nice!

QUOTE=jhein;6582451]FYI, Frank's has a few decent 400/455 blocks available.[/QUOTE]

Wonder what Frank would charge for a 400 or 455 block crank and pistons?

77 TRASHCAN 09-18-2025 09:57 AM

I'm always on the look out for a 455, totally complete from oil pan to air cleaner, out of a :A: or "F" body. I've read her the brackets allow all the accessories to fit under the hood of either one of those cars. Of course I only have a "F" body, my TA, hence my reasoning.

You don't see much of that going on any more...of course it all depands upon price and condition...and what version of engine...

mgarblik 09-18-2025 09:58 AM

I still see 400-455 blocks on Facebook Marketplace on a regular basis. They are not listed every day like in the past, but people and estates are still purging them. Picked up 2 73 455 blocks and cranks for $500.00 not long ago. One std bore, one +.030. Sold one for $500.00 with good crank and kept one. Just keep your eyes open, one will find you.

thepontiacman 09-19-2025 09:58 PM

Good luck with your build.

You know I have 400's and 455's here in Talladega, but not at screaming deal prices mentioned above.



Sent from my moto g power 5G - 2023 using Tapatalk

Half-Inch Stud 09-20-2025 08:12 AM

Not quite a "build". Tore down the short block; #8 rod spun the bearing tabs gave up, but no overlap. Not sure if worth crank cut .010 on rods.

Nor tanking block. Pistons looked fine after gasoline scrub. Bores look good from 3' away.need a closer look.

@Pontiacman; maybe a quote on a 455 block crank pistons?

thepontiacman 09-23-2025 03:13 PM

PM sent

Half-Inch Stud 09-24-2025 09:04 AM

Cleaned most parts. Who does this: each bottleneckrocker stud has teflon tape wrapped on the jamnut threads, as if to keep an oil puddle in the rocker ball. Which it doesn't do. So maybe was to keep the nut tight which it also doesn't do.

Half-Inch Stud 09-27-2025 08:25 AM

Might be buying a 4-bolt 421Block& Crank, 4X Heads, with some small parts.

tempest1964 09-27-2025 08:55 AM

Hope you get the 421 block. Mine seemed very beefy on the thickness of the lifter bosses, etc. What year is the casting? I think they changed the oiling the last year or two.

Half-Inch Stud 09-27-2025 05:05 PM

1 Attachment(s)
Got these items: 4-bolt 421 STD Bore, STD Arma Steel crank(checked good to stay STD), some new Main+Cam Bearings, 8 Cast rods, wind-tray, 4X Heads bare, M/T Valve Covers with Offy Breathers, 2 used-"maybe good" cams 1 is the 66 421 cam, and the GM HO Manifolds.

And an ability to drop-off scrap iron ( the freebyPontiac 350 Block, Crank, Pistons from 1st Post.

Seller ground my 2 455 Cranks Pre-Covid.

Tings i'm gonna need:
428 STD bore Pistons & Rings
Forged rods
Manifold with Fuel-Injector bosses, prefer Dual-Plane, but maybe a Tomahawk.
Large inlet oil pump
Rear seal, gasket set, The good valve seals
2.11, 1.66 1-piece stainless Valves
8QTY 1.5:1 roller rockers.
HO Exh flanges and short downpipes
2-bolt Motor Mounts.
HYd Lifters, really old stock.

I post the stopid stuff with needfuls in case a fella has em and we make a deal.


All times are GMT -4. The time now is 12:18 PM.