What is the truth on BB 4x4's - The 1947 - Present Chevrolet & GMC Truck Message Board Network

eedgell · 05-05-2007, 05:43 PM

were there any Big Block 4x4's made or not? I have heard it both ways. Also I have heard that it is difficult to put a BB in a 4x4.? If so why? Not to be dumb, but my 71' cheyenne is my first of this style. 1973 to 1987's love BB's and is no problem on install. If they are different, why?

eedgell

1969k10stepside · 05-05-2007, 05:45 PM

No big block 67-72s were 4wd originally.The problem is clearance when you put one in.The valve covers and distributor hit the firewall in many cases.It can be fixed so a BBC can go in by using a body lift,moving the motor and transfer case crossmember forward,or doing some firewall work.I dont know exactly why the 73+ are different but it may be because the motor is farther forward.The 73+ uses a different motor mount crossmember too.

Longhorn Man · 05-05-2007, 07:11 PM

exactly, there were none made.

eedgell · 05-05-2007, 07:27 PM

Ok, but plenty were made in 2WD. Other than drive trane, what is different in the cab chassis to make the big block not fit?

eedgell

**Classic Heartbeat** · 05-05-2007, 08:14 PM

The engine crossmember. It is located too far back in the engine compartment to give the motor the clearence on the firewall. A big hammer fixes that problem, or moving the motor forward, withch opens up it's own can of worms. As well as a body lift. Been there, done that, got the "T" shirt....lol WES www.ClassicHeartbeat.com

**special-K** · 05-05-2007, 09:28 PM

I guess the motors (all) sit back into the firewall in a 4wd to keep clearance for the solid front drive axle.With the new body designed for`73,they worked it out to fit.They designed the cab/firewall to give more room.Remember,no big blocks at all until`68.

1969 GMC · 05-05-2007, 09:38 PM

Quote:

Originally Posted by eedgell

were there any Big Block 4x4's made or not?

Not until the 73-87 trucks did this happen. Not sure what year it happened, but I have personally seen an '87 V30 crew cab dually with a TBI 454 that was bone stock (showed up on the SPID sticker), so I know that they're out there.

I also want to know if there were any solid axle 4x4 big block suburbans made...I don't think there were. Same with K5's. Or even really anything but 1 tons. I can't remember ever seeing one.

CrashEd · 05-06-2007, 06:15 AM

I just put a 402 in my 72 4x4 and it was as easy as just changing small blocks other than the little bends i put in the firewall. I just used the small block motor mounts and it droped right in. The only problem i have now is tire traction.
Ed

GREASEMONKEY72 · 05-06-2007, 06:26 AM

Quote:

Originally Posted by CrashEd

The only problem i have now is tire traction.
Ed

maybe thats why the factory didnt put them in the 4x4s

Bishops Trucks · 05-06-2007, 06:49 AM

I had one in my '71 4X4 when I bought it. Someone massaged the firewall to get the distributer to fit but MSD makes one for firewall clearance issues.

hgs_notes · 05-06-2007, 09:05 AM

I'm looking at a junkyard blazer with no drive train and was thinking about putting a big block in it. The cross member under the engine was cut out and needs replaced. Will the 73 and up cross members fit? Could I make one with pipe and plate to allow clearance to slide it forward or would it still need the body lift or firewall hammer adjustment?

**Classic Heartbeat** · 05-06-2007, 02:29 PM

The 73 up crossmember will not fit. I was going to go that rout on project muscle truck because the motor mounts are stronger, however after altering the crossmember to make it fit, it didn't set right. So I will now alter a stock crossmember to allow for the newer motor mounts. WES www.CalssicHeartbeat.com

**Yukon Jack** · 05-07-2007, 11:37 AM

Quote:

Originally Posted by hgs_notes

I'm looking at a junkyard blazer with no drive train and was thinking about putting a big block in it. The cross member under the engine was cut out and needs replaced. Will the 73 and up cross members fit? Could I make one with pipe and plate to allow clearance to slide it forward or would it still need the body lift or firewall hammer adjustment?

Burt4x4 initially used a 73-up engine crossmember when he put in his bbc - then he went to an aftermarket crossmember.

Bram · 05-07-2007, 11:48 AM

Basically what I did is connect all three together and dropped the transfer case in the original holes; this gave me plenty of firewall clearance with the BB, with no other mods like body lift. All I had to do was move the motor mounts forward and drill new holes. Hope this helps a little?

hgs_notes · 05-07-2007, 05:39 PM

Bram, excellent photos and nice looking rig. What headers are those? Is that the stock front cross member and motor mounts, just slid forward?

Bram · 05-07-2007, 05:50 PM

Quote:

Originally Posted by hgs_notes

Bram, excellent photos and nice looking rig. What headers are those? Is that the stock front cross member and motor mounts, just slid forward?

Thanks! They are Doug Thorley headers, and yes it was the stock cross member and motor mounts.

DieselEater · 05-07-2007, 07:13 PM

I used a cross member from an 80' with new holes drilled...at least 3 inches clearance behind the distributor...Also used the 80 drivetrain...cut the rear shaft to fit.

Next time I'll use stock parts and dent the firewalls!!!!

eedgell · 05-07-2007, 11:23 PM

That all makes much more cents than beeting up the fire wall. I bought mine with the bigg-es block-es hard as rock-es 454 already in with no fire wall damage. Men built them, we can build them better!!

*72longbed* · 05-08-2007, 08:53 AM

Bram,
what brand/make is that duel electric fan setup? Does it do the job for you?

Thanks,
72longbed

Bram · 05-08-2007, 09:01 AM

Quote:

Originally Posted by 72longbed

Bram,
what brand/make is that duel electric fan setup? Does it do the job for you?

Thanks,
72longbed

It was a Be Cool setup, and yes it does quite well. Never had a problem with over heating even when pulling a four horse gooseneck through these Ozark hills in 95 degree weather, or idling around a field hauling hay.

05-05-2007, 05:43 PM	#1
eedgell It's the air up here Join Date: Mar 2007 Location: Western Colorado Posts: 710	What is the truth on BB 4x4's were there any Big Block 4x4's made or not? I have heard it both ways. Also I have heard that it is difficult to put a BB in a 4x4.? If so why? Not to be dumb, but my 71' cheyenne is my first of this style. 1973 to 1987's love BB's and is no problem on install. If they are different, why? eedgell __________________ 1971 cheyenne k10 4 speed np 205 454 BB factory a/c Never drink down stream of the herd! Eric

05-05-2007, 05:45 PM	#2
1969k10stepside Registered User Join Date: Mar 2006 Location: USA Posts: 21,020	Re: What is the truth on BB 4x4's No big block 67-72s were 4wd originally.The problem is clearance when you put one in.The valve covers and distributor hit the firewall in many cases.It can be fixed so a BBC can go in by using a body lift,moving the motor and transfer case crossmember forward,or doing some firewall work.I dont know exactly why the 73+ are different but it may be because the motor is farther forward.The 73+ uses a different motor mount crossmember too. Last edited by 1969k10stepside; 05-05-2007 at 09:39 PM. Reason: spelled transfer case wrong...

05-05-2007, 07:11 PM	#3
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Re: What is the truth on BB 4x4's exactly, there were none made.

05-05-2007, 07:27 PM	#4
eedgell It's the air up here Join Date: Mar 2007 Location: Western Colorado Posts: 710	Re: What is the truth on BB 4x4's Ok, but plenty were made in 2WD. Other than drive trane, what is different in the cab chassis to make the big block not fit? eedgell __________________ 1971 cheyenne k10 4 speed np 205 454 BB factory a/c Never drink down stream of the herd! Eric

05-05-2007, 08:14 PM	#5
Classic Heartbeat Project Junkie! Fishing Poor!! Join Date: Dec 1999 Location: Olympia,Wa. 98512 Posts: 10,770	Re: What is the truth on BB 4x4's The engine crossmember. It is located too far back in the engine compartment to give the motor the clearence on the firewall. A big hammer fixes that problem, or moving the motor forward, withch opens up it's own can of worms. As well as a body lift. Been there, done that, got the "T" shirt....lol WES www.ClassicHeartbeat.com __________________ On-line catolog Classic Heartbeat Pickup Parts WEHEPP@comcast.net Call us Toll Free (888) 338-2502 Like Us on Facebook No appointment necessary. 72 BB Chevy Custom Deluxe / Custom Camper 67 I-6 (Soon to be 5.7 LS1) Panel 68 BB Chevy Short Bed 72 6.0 LQ9 Short Bed Chevy 4X4 Olympia's fastest growing truck parts supplier. Olympia's home for Wayward Chevys

05-05-2007, 09:28 PM	#6
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,858	Re: What is the truth on BB 4x4's I guess the motors (all) sit back into the firewall in a 4wd to keep clearance for the solid front drive axle.With the new body designed for`73,they worked it out to fit.They designed the cab/firewall to give more room.Remember,no big blocks at all until`68. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ Last edited by special-K; 05-05-2007 at 09:29 PM.

05-06-2007, 06:15 AM	#8
CrashEd 72 chevy Join Date: Jan 2007 Location: Central Il Posts: 725	Re: What is the truth on BB 4x4's I just put a 402 in my 72 4x4 and it was as easy as just changing small blocks other than the little bends i put in the firewall. I just used the small block motor mounts and it droped right in. The only problem i have now is tire traction. Ed

05-06-2007, 06:49 AM	#10
Bishops Trucks KEEP ON TRUCKIN' Join Date: Jun 2005 Location: Sterling, Va. Posts: 5,731	Re: What is the truth on BB 4x4's I had one in my '71 4X4 when I bought it. Someone massaged the firewall to get the distributer to fit but MSD makes one for firewall clearance issues. __________________ JIM '97 GMC Sierra K1500 '95 Chevy Silverado C1500 '71 Cheyenne Z71 / LT1 & 4-Speed SWB K/10 Father/Son Project http://www.youtube.com/watch?v=4l689JKXPnA http://67-72chevytrucks.com/vboard/payments.php "LIVIN' FREE FOREVER"

05-06-2007, 09:05 AM	#11
hgs_notes GEARHEAD Join Date: Aug 2003 Location: MN Posts: 6,122	Re: What is the truth on BB 4x4's I'm looking at a junkyard blazer with no drive train and was thinking about putting a big block in it. The cross member under the engine was cut out and needs replaced. Will the 73 and up cross members fit? Could I make one with pipe and plate to allow clearance to slide it forward or would it still need the body lift or firewall hammer adjustment? __________________ If no one knows what you're doing, they can't tell you you're doing it wrong HG's Dream Car Build - Shelby Cobra Kit Build your own adjustable track bar 71 Long Fleet C/10 72 Jimmy 4x4 (Junkyard Jimmy) HG's Plow Truck '78 K35 Dually Bigass Farm Truck HG's thread of miscellaneous stuff

05-06-2007, 02:29 PM	#12
Classic Heartbeat Project Junkie! Fishing Poor!! Join Date: Dec 1999 Location: Olympia,Wa. 98512 Posts: 10,770	Re: What is the truth on BB 4x4's The 73 up crossmember will not fit. I was going to go that rout on project muscle truck because the motor mounts are stronger, however after altering the crossmember to make it fit, it didn't set right. So I will now alter a stock crossmember to allow for the newer motor mounts. WES www.CalssicHeartbeat.com __________________ On-line catolog Classic Heartbeat Pickup Parts WEHEPP@comcast.net Call us Toll Free (888) 338-2502 Like Us on Facebook No appointment necessary. 72 BB Chevy Custom Deluxe / Custom Camper 67 I-6 (Soon to be 5.7 LS1) Panel 68 BB Chevy Short Bed 72 6.0 LQ9 Short Bed Chevy 4X4 Olympia's fastest growing truck parts supplier. Olympia's home for Wayward Chevys

05-07-2007, 11:48 AM	#14
Bram Broke Join Date: Aug 2001 Location: West Plains,MO Posts: 385	Re: What is the truth on BB 4x4's Basically what I did is connect all three together and dropped the transfer case in the original holes; this gave me plenty of firewall clearance with the BB, with no other mods like body lift. All I had to do was move the motor mounts forward and drill new holes. Hope this helps a little? __________________ 72CheyenneSuper1ton4x4BigBlock

05-07-2007, 05:39 PM	#15
hgs_notes GEARHEAD Join Date: Aug 2003 Location: MN Posts: 6,122	Re: What is the truth on BB 4x4's Bram, excellent photos and nice looking rig. What headers are those? Is that the stock front cross member and motor mounts, just slid forward? __________________ If no one knows what you're doing, they can't tell you you're doing it wrong HG's Dream Car Build - Shelby Cobra Kit Build your own adjustable track bar 71 Long Fleet C/10 72 Jimmy 4x4 (Junkyard Jimmy) HG's Plow Truck '78 K35 Dually Bigass Farm Truck HG's thread of miscellaneous stuff

05-07-2007, 07:13 PM	#17
DieselEater Registered User Join Date: Dec 2006 Location: Trinidad, Colorado Posts: 642	Re: What is the truth on BB 4x4's I used a cross member from an 80' with new holes drilled...at least 3 inches clearance behind the distributor...Also used the 80 drivetrain...cut the rear shaft to fit. Next time I'll use stock parts and dent the firewalls!!!! __________________ 69' 3/4 4X4 470ci BBC 700 HP.... D60/14bolt 205/465 http://profile.myspace.com/index.cfm...ndid=127691959

05-07-2007, 11:23 PM	#18
eedgell It's the air up here Join Date: Mar 2007 Location: Western Colorado Posts: 710	Re: What is the truth on BB 4x4's That all makes much more cents than beeting up the fire wall. I bought mine with the bigg-es block-es hard as rock-es 454 already in with no fire wall damage. Men built them, we can build them better!! __________________ 1971 cheyenne k10 4 speed np 205 454 BB factory a/c Never drink down stream of the herd! Eric

05-08-2007, 08:53 AM	#19
72longbed Account Suspended Join Date: Jun 2003 Location: PA Posts: 1,411	Re: What is the truth on BB 4x4's Bram, what brand/make is that duel electric fan setup? Does it do the job for you? Thanks, 72longbed



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