Technical MOTOR, 348-409 Information

348:
Bore - 4.125"
Stroke - 3.25"
Rod Size - 6.135"
Firing Order - 1-8-4-3-6-5-7-2
Weight - 645 Pounds
Forged Crank - Round flywheel bolt flange
Crank mains - 2.4977"
Pushrod Length - Ex. 9.140" IN. 8.772"
Pushrod Diameter - 5/16"
Dipstick - Driver Side (Passenger Side on trucks)
Ignition Timing - 4 degrees before top dead center
Spark Plugs - AC44(Standard) AC45(Hot) AC43(Cold)
Spark Plug Gap - .035"
Rocker Arm Ratio - 1.75:1
Internally Balanced

409:
Bore - 4.312"
Stroke - 3.5"
Rod Size - 6.0"
Firing Order - 1-8-4-3-6-5-7-2
Weight - 645 Pounds
Forged Crank - Bell Shaped Flywheel bolt flange
Crank Mains - 2.4977"
Pushrod Length - EX. 9.140" IN. 8.772"
Fuel Pump Pushrod Lengh - 5.75"
Dipstick - Passenger Side
Spark Plugs - AC43N (standard) AC44N(Hot) AC42n(Cold)
Spark Plug Gap - .035"
Rocker Arm Ratio - 1.75:1

(more coming in a few minutes)

 

Interchangable Parts:

Part Small Block Big Block
Points Yes Yes
COndensor Yes Yes
Distributor Cap Yes Yes
Rotor Yes Yes
Vaccuum Advance Yes Yes
Distributor Gear Yes Yes
Rear Main Seal No Yes
Timing Cover Seal Yes No
340HP 409 Valve Springs Yes No
Connecting rod bearings No Yes
Oil Pump Shaft No Yes
Oil Pump Yes No
Oil Filter Cartridge Yes Yes
Oil Filter Canister Yes Yes
Fuel Pump Yes No
Fuel Pump Mounting Plate Yes No
Fuel Pump Pushrod Yes Yes
Water pump bearing Yes No
Water Pump Seal Yes No
Water Pump Impeller Yes No

(more coming)

 

Casting Numbers:

Blocks:
3732755.....348......59-61
3732811.....348......58
3751872.....348......58
3755011.....348......59-61
3771705.....348......59-61
3782012.....348......58-61
3788068.....409......62-63
3795623.....409......61
3798962.....348......62-65...Truck
3815707.....348......58-61
3830814.....427......63......"Z11" (4.312" bore x 3.65" stroke)
3830814.....409......63-64
3839752.....409......62-63
3839754.....409......65
3844422.....409......63-65
3857655.....348......62-65...Truck
3857656.....409......64-65
3860386.....409......62-64
3860387.....348......58



Heads:
3732791.....348......58-60
3758379.....348......59-61...250 hp
3759256.....348......58
3759332.....348......58-60
3764702.....348......60......Truck
3767738.....348......59-60...250 hp
3781147.....348......60-61...HiPerf, 2.06"/1.72" valves
3795586.....348/409..61......HiPerf, 2.06"/1.72" valves
3814690.....409......62-63...HiPerf, 2.19"/1.72" valves
3815857.....348/409..58-62...Truck
3819333.....348/409..62-65...HD Truck
3830817.....409......63-65...340 hp
3837731.....427......63......"Z11" (4.312" bore x 3.65" stroke)
3852583.....409......63-65...HiPerf, 2.19"/1.72" valves

 

http://img.photobucket.com/albums/v428/johnnyb327/Topv-cover.jpg A valve cover with a low spark plug holder is from a 348 tri-power

http://img.photobucket.com/albums/v428/johnnyb327/2ndV-cover.jpg a high valve cover holder is from 348 and 409 motor (less tripower) built between 58 and 62.

http://img.photobucket.com/albums/v428/johnnyb327/3rdv-cover.jpg 63-65 all 409's used valve covers with a high spark plug holder featuring a plastic fixture.

http://img.photobucket.com/albums/v428/johnnyb327/4thv-cover.jpg Truck engines used the valve covers with the spark plug fixture thats near the middle.

http://img.photobucket.com/albums/v428/johnnyb327/5thv-cover.jpg Hi-po 409s built between 62 and 65 featured the internal oil drippers.

That's all

 

Actually thats not all sorry....Right as I pressed that I thought I would add a tips section when building....

With the truck engines, since they have the notch in the cylinder, bore them to not only add more piston area, but to also fill that notch more.

The ports are pretty small on a lot of the heads, so match port them with the intake and exhaust manifolds.

Oh yeah, add as many cubic inches possible!

John

 

Cool info on the W block, I am going to have to save this thread so i can print it out when I get home.

Jonney

 

I was not aware that so much of the distributors were the same, considering the distributors themselves will not interchange. I'll have to remember that for my motor.

 

not important, but the 348 figures on stroke are off i think. as listed, it gives ya like 440 ci. bore looks right to me, but stroke oughta be around 3.25 or therabouts. the rest of the info is much appreciated. i love W blocks.

 

whoa shit I fucked up on the stroke....sorry guys

 

Thanks, good info for fresh W-engine owner like me!

 

Yeah, this will be saved. Any good ideas for combinations on making 500hp (ish) without having to claw some hipo heads out of a hoarders hands???

 

Also worth mentioning as a 'spotter's trick'...348 engines have the oil dipstick on the driver's side, where 409 engines have it on the passenger's side. Makes it easier to distinguish the two motors at a glance...especially when that "409" at the swap meet ends up being a 348 truck engine!

 

Good piece of advice for car engines, but I've got a late 348 out of a motorhome that has the deep pan and dipstick on the passenger side. Best thing to do is check the casting numbers. Pans can get changed. Not that an original 409 pan wouldn't be a good score at a swap.

 

Early 58 blocks and heads made after 58 WONT work together without some modification. In 58 the factory added some meat on the outside of the sparkplug area of the head, In 59, they added waterpassages with corresponding holes in the block. the late 58 blocks had extra meat on the outside and you can drill out the water holes to match those in the heads. On the early blocks, the holes in the head hang OVER the edge on the block deck!

I made mine work by welding the 4 little holes in the heads.

 

Great post, Johhny and good info T-man.

I am collecting parts for my Impala to do a 348 4sp conversion down the road.

This thing followed me home the other day:

 

whats this doin way back here?

to the TOP!

 

Bore a 409 .030 and then put a 454 crank in it. Port match the heads and intake. Get a isky cam and then run it. I think the final CID is close to 477. So 500 horsepower wouldn't be too far off

 

July 2001 issue of R&C had a good article titled "Mighty Fine 409" that was about pulling 500 ponies out of the engines. If anyone wants a copy I'll see if I can make a pdf file out of it to send out.

 

YES! (please)

 

Man,,,awesome info....I heard that alot of stuff was interchanable,,,but you just never know sometimes..I had a 348 w/3 deuces that i planned on putting in my Model A but had to switch things up...Kind of wish i didnt get rid of it....But i guess i will find another one someday...lol

But i'm about to burn these printers up at work now...Thanks for taking the time to post this info!

Dirty

 

Me too. That would be great. Thanks.

 

that would be great!

 

Igorw,

Thanks for the E-mailed article. I found a link to it in the net also. Here it is.

http://www.348-409.com/literature/cc409story.html

 

You have a choice here with the stroker kit: You can either turn down the mains on the crank, or align bore the block/main caps. When making this choice, as yourself this: if you were putting that 454 crank in a 454 block, would you turn one down that far? The answer is no.
Bore the block and caps. Or, more to the point, ditch the 2-bolt caps, add ProGram 4-bolt caps, and then align bore them. To quote Lamar Walden, "If you just turn down that crank and keep the two-bolt mains, that crank is going to whip around down there like a licorice stick." You'll end up with a broken crank.

Comp makes really good cams for these engines, too. And they've got much more modern lobe profiles available for even more power.

-Brad

 

OK, so I got a 3830814 block stuffed with pistons with no heads. How do I know if it's a 427????????? It's got a 61 crank....oh well...

 

BLOWER!!!

 

Anyone make a blower intake for one?

(and I have zero machining skills. I can't even cut a 2X4 straight.)

 

I know somebody that does...

 

WHO?! (really, you couldn't just post it? You gotta make me ask?!)

 

check the bore! I'll bust out the 427 bore info for ya in a few minutes