427 industrial engine swap??? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

68_GMC_910 · 09-22-2002, 07:08 PM

As you may know my truck right now has a 250 straight six and 3 speed manual... 4:11s with no posi yet (I'm workin' on that)

I was almost sure I was going to be normal and go with a small block chevy 350 and 4 speed, but now I'm not so sure at all...

the 427 BB from the C60/C70/ect... have peaked my interest... I wanna put one in my '68 and I have a few questions...

- is this a good idea for a swap?

-can I mount the engine on the six-banger mounts?

-I'm aware these motors came attached to SM420s and SM465s stock for manuals... I want a faster transmission with higher gears... what tranny do you reccomend for a truck that will be raced and are there any other trannies I might find in these trucks with these engines? (slushboxes)

-what trannies will or will not bolt up to the Bellhousing?

lukecp · 09-22-2002, 08:21 PM

The bellhousing pattern on the 366/427 "tall deck" motors is exactly the same as on all other Chevy inline 6, SB, and BB engines. I would put a TH400 behind the 427, it is known to be a tourqe monster. For racing and going fast, you would proably be better off spending your money on a 396, 402, 427 (regular deck height), or 454. The tall deck 427 is a good motor for a dump truck, but it won't rev as high or make as much horsepower as a regular deck height BBC. You can buy performance parts for them though. I am pretty sure that any aftermarket BBC head will bolt on, and so will the intakes if you use a set of spacers. The distributor is a little different on a tall deck, i think it is a bit longer.

Longhorn Man · 09-23-2002, 02:18 AM

I would not bother onless you are spending 10K on a mountian motor.
No upper end, way too much lower end, hard to get the aftermarket parts.
Although they do have steel cranks if I am not mistaken.

palallin · 09-23-2002, 05:20 PM

Quote:

Originally posted by longhornmail
No upper end, way too much lower end, . . . .

However, for those of you of the 4x4-building ilk, it ought to be just what the truck needs.

Mike C · 09-23-2002, 06:09 PM

A tall deck 427 is significantly wider than a regular deck 427. Makes squeezing exhaust in difficult. GM went to a taller deck in order to add another piston ring to the assembly. This was required because the engines are designed to operate at continuous WOT and the extra rings transfer heat from the pison assembly. You can buy tall deck intakes, adjustable slip collar distributors and use any Mark IV cylinder head as a replacement for the peanut port truck heads. They have small port for high velocity, small valves and large valve stems. The large valve stems have more surface area in order for more contact with the guide to shed heat and the small valves have a smaller surface area all to keep heat in the chamber. All in all you'd be better off finding a 402 from a car or truck, a pasenger car 427 or a 73-84 454.

68_GMC_910 · 09-23-2002, 06:34 PM

wow. that's very interesting. thanks for the input.

09-22-2002, 07:08 PM	#1
68_GMC_910 what would Neal do? Join Date: Sep 2002 Location: Winnipeg, Manitoba, Canada Posts: 150	427 industrial engine swap??? As you may know my truck right now has a 250 straight six and 3 speed manual... 4:11s with no posi yet (I'm workin' on that) I was almost sure I was going to be normal and go with a small block chevy 350 and 4 speed, but now I'm not so sure at all... the 427 BB from the C60/C70/ect... have peaked my interest... I wanna put one in my '68 and I have a few questions... - is this a good idea for a swap? -can I mount the engine on the six-banger mounts? -I'm aware these motors came attached to SM420s and SM465s stock for manuals... I want a faster transmission with higher gears... what tranny do you reccomend for a truck that will be raced and are there any other trannies I might find in these trucks with these engines? (slushboxes) -what trannies will or will not bolt up to the Bellhousing? __________________ 1968 GMC 910 Long Step 250/3onTree 1969 Chevy C10 longfleet, 350/350 Last edited by 68_GMC_910; 09-22-2002 at 07:12 PM.

09-22-2002, 08:21 PM	#2
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	The bellhousing pattern on the 366/427 "tall deck" motors is exactly the same as on all other Chevy inline 6, SB, and BB engines. I would put a TH400 behind the 427, it is known to be a tourqe monster. For racing and going fast, you would proably be better off spending your money on a 396, 402, 427 (regular deck height), or 454. The tall deck 427 is a good motor for a dump truck, but it won't rev as high or make as much horsepower as a regular deck height BBC. You can buy performance parts for them though. I am pretty sure that any aftermarket BBC head will bolt on, and so will the intakes if you use a set of spacers. The distributor is a little different on a tall deck, i think it is a bit longer. __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

09-23-2002, 06:09 PM	#5
Mike C Registered User Join Date: Dec 1999 Location: Austin, TX, USA Posts: 7,709	A tall deck 427 is significantly wider than a regular deck 427. Makes squeezing exhaust in difficult. GM went to a taller deck in order to add another piston ring to the assembly. This was required because the engines are designed to operate at continuous WOT and the extra rings transfer heat from the pison assembly. You can buy tall deck intakes, adjustable slip collar distributors and use any Mark IV cylinder head as a replacement for the peanut port truck heads. They have small port for high velocity, small valves and large valve stems. The large valve stems have more surface area in order for more contact with the guide to shed heat and the small valves have a smaller surface area all to keep heat in the chamber. All in all you'd be better off finding a 402 from a car or truck, a pasenger car 427 or a 73-84 454. __________________ 44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax

09-23-2002, 06:34 PM	#6
68_GMC_910 what would Neal do? Join Date: Sep 2002 Location: Winnipeg, Manitoba, Canada Posts: 150	wow. that's very interesting. thanks for the input. __________________ 1968 GMC 910 Long Step 250/3onTree 1969 Chevy C10 longfleet, 350/350

09-23-2002, 02:18 AM	#3
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	I would not bother onless you are spending 10K on a mountian motor. No upper end, way too much lower end, hard to get the aftermarket parts. Although they do have steel cranks if I am not mistaken.



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