BBC in 4X truck - The 1947 - Present Chevrolet & GMC Truck Message Board Network

FIVE 0 · 03-18-2006, 10:59 PM

Brand new here and first post. Im sure its been asked several times but cant find it in old posts. Im in the middle of putting a BB in my 4X and as you all know its not just a drop swap. Whats the most popular way of doing this? Cutting into the firewall, moving tranny and transfer, or not doing it at all. I made the mistake of driving the donor rig with the 454 and now cant get it out of my mind. I would like any advise from any of you who have tried this. Thanks.

**BOSS** · 03-18-2006, 11:06 PM

First Welcome to the board!!! I think you could pm Yukon Jack,he has done it and has alot of pics showing details,maybe he will chime in here.again welcome

FIVE 0 · 03-18-2006, 11:09 PM

Thanks for the welcome and info. I will PM him and see what hes got. Thanks.

**too much stuff** · 03-18-2006, 11:13 PM

Welcome, and i just finessed the firewall where the hei rubbed, got some corvette valve covers with the brake booster notch, and a pair of 77 stock exhaust manifolds from a 1/2 ton truck. This was about 8 years ago. Went fairly smooth from what i remember.

FIVE 0 · 03-18-2006, 11:18 PM

Thats good info. I was looking at Vette valve covers on ebay thinking that my help, being the drivers side is the closest. Im also going to run an HEI and im sure I may have to work that area over to when I get there. Thanks.

**too much stuff** · 03-18-2006, 11:27 PM

On my valve cover, i still had to grind a little off the lip where it hangs over the head and had to pull the tail light wires to the side a hair. I also had to grind a "nub" of the stock exhaust manifold to clear the cross member. I will post more as i think of it, or i can try to get some pics. I set mine on the 350 mounts. I hear a body lift makes it easier, but i don't have that.

sakohntr · 03-18-2006, 11:31 PM

Use all the small block motor mounts and move the whole assembly forward 2 inches. If its a stick you'll have to move the clutch z-bar pivot as well.

FIVE 0 · 03-18-2006, 11:45 PM

If you move the rest forward, how does the rear driveline fair? I think my front one can take it but not sure about the rear. Thanks Ror

FIVE 0 · 03-19-2006, 12:45 AM

Just got moved here and thought I should add a little info that may help. Its a 72 3/4 4X with an auto. Thanks.

4x4Poet · 03-19-2006, 06:18 AM

The BBC is a little longer from the center of the mm to the bellhousing mounting surface, so that should help mitagate moving the whole engine foward. Not that I'm saying that's the thing to do. I'm sure there's a site with BBC vs. SBC dimensions.

One can use a 73up crossmember so clamshell mm can be used. Try a search on 4x4 & BBC and crossmember or xmember and some BBC into 4x4 threads should come up.

If one moves the z-bar mount foward with the BBC, how does one elongate the pedal rod from clutch pedal to z-bar? Cut, sleeve, and weld?

Some one once mentioned using a '70s BBC mech clutch z-bar set up from clutch pedal rod to clutch fork, but I haven't been able to ascertain the reason why or advantage in doing so. If there truly is an advantage. Hydraulic clutch is an option with fabbing and the right bellhousing.

FIVE 0 · 03-19-2006, 11:27 AM

Im running a TH 350 auto, hope it holds up, so I dont need to worry about the clutch linkage. I will look at other xmembers though. Thanks for the info.

**Yukon Jack** · 03-19-2006, 05:32 PM

Welcome to the board and I hope the info I pm'd ya helps you with the swap. I was going to post the article on the 73-8something engine crossmember, but I must have it on my office computer. I will get it posted for you tomorrow.

**kwmech** · 03-20-2006, 01:15 AM

[QUOTE=4x4Poet]The BBC is a little longer from the center of the mm to the bellhousing mounting surface.

The measurements are identical---small block, big block, 6.2 and 6.5 diesels

4x4Poet · 03-20-2006, 07:29 AM

[QUOTE=kwmech]

Quote:

Originally Posted by 4x4Poet

...The measurements are identical---small block, big block, 6.2 and 6.5 diesels

Coulda swore I'd seen different in engine dimension diagrams with the "A, B, C, etc. measurements," but I'm sure my memory is at fault. Thanks for the correction.

**Yukon Jack** · 03-20-2006, 11:24 AM

Here is the article on the new engine crossmember link 1 link 2

qksilver · 03-20-2006, 01:38 PM

That article make it look so easy............
I have all the later model stuff , I will try it on the second to next project!

FIVE 0 · 03-20-2006, 08:03 PM

Outstanding link. Just printed it out. Thanks again for the info. Ror

454_72_4X4 · 03-21-2006, 01:10 AM

I'd have to agree. The 73+ X-member would be the way to go. I didn't know about that when I did mine the first time so it sits on the stock 350 mounts and x-member.

I "clarenced" the firewall on both sides but didn't have any problems with the HEI. It has all kinds of room, almost 3/16 of an inch! LOL

I used the right manifold off of a mid seventies BB pickup and the left was off of a 66 BB car, (Impala I assume). The car manifold has since cracked into 3 pieces and I replaced it with an unkown manifold. I had to remove a little "slice" off of the frame and remodel the engine mount some to get the replacement manifold to fit.

BB and SB motor mount dimensions are the same so there's no worries there.

4x4Poet · 03-23-2006, 06:39 AM

That link to a 4x4Power mag article is the one I have that I've posted about several times. I don't have a digicam, unfortunately.

The BBC radiator shroud shown doesn't look like a 67-72 2wd BBC shroud to me. It looks like a either a 73up shroud or maybe a 2wd SBC shroud. The one in back of the BBC shroud does look like a 67-72 4x4 SBC shroud.

03-18-2006, 10:59 PM	#1
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	BBC in 4X truck Brand new here and first post. Im sure its been asked several times but cant find it in old posts. Im in the middle of putting a BB in my 4X and as you all know its not just a drop swap. Whats the most popular way of doing this? Cutting into the firewall, moving tranny and transfer, or not doing it at all. I made the mistake of driving the donor rig with the 454 and now cant get it out of my mind. I would like any advise from any of you who have tried this. Thanks.

03-18-2006, 11:06 PM	#2
BOSS Just here to help Join Date: Jan 2002 Location: Norwood,Mo Posts: 3,893	Re: BBC in 4X truck First Welcome to the board!!! I think you could pm Yukon Jack,he has done it and has alot of pics showing details,maybe he will chime in here.again welcome __________________ Support our site Norwood Survivor

03-18-2006, 11:09 PM	#3
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	Re: BBC in 4X truck Thanks for the welcome and info. I will PM him and see what hes got. Thanks.

03-18-2006, 11:13 PM	#4
too much stuff Roadtrip! Join Date: Feb 2003 Location: Grand Rapids MN Posts: 13,712	Re: BBC in 4X truck Welcome, and i just finessed the firewall where the hei rubbed, got some corvette valve covers with the brake booster notch, and a pair of 77 stock exhaust manifolds from a 1/2 ton truck. This was about 8 years ago. Went fairly smooth from what i remember. __________________ 67 gmc custom lwb dakota truck. Sold...And bought back 69 swb 4x4 project (in progress) 70 c-10 lwb texas truck 70 4x4/BB/bkts/posi/tach(retired) 70 swb (wifes) 70 jimmy camper 71 K-5 factory 2wd 71 cheyenne 4x4/tach/posi/ plow rig 71 Cheyenne20 BB, buckets, tach, tilt, 4 speed 72 jimmy CST wyoming rig 72 jimmy Colorado rig 72 lifted texas 4x4 3/4 ton burb 65 fury conv. 383/auto 65 chrysler 300 "L" 413 auto

03-18-2006, 11:18 PM	#5
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	Re: BBC in 4X truck Thats good info. I was looking at Vette valve covers on ebay thinking that my help, being the drivers side is the closest. Im also going to run an HEI and im sure I may have to work that area over to when I get there. Thanks.

03-18-2006, 11:27 PM	#6
too much stuff Roadtrip! Join Date: Feb 2003 Location: Grand Rapids MN Posts: 13,712	Re: BBC in 4X truck On my valve cover, i still had to grind a little off the lip where it hangs over the head and had to pull the tail light wires to the side a hair. I also had to grind a "nub" of the stock exhaust manifold to clear the cross member. I will post more as i think of it, or i can try to get some pics. I set mine on the 350 mounts. I hear a body lift makes it easier, but i don't have that. __________________ 67 gmc custom lwb dakota truck. Sold...And bought back 69 swb 4x4 project (in progress) 70 c-10 lwb texas truck 70 4x4/BB/bkts/posi/tach(retired) 70 swb (wifes) 70 jimmy camper 71 K-5 factory 2wd 71 cheyenne 4x4/tach/posi/ plow rig 71 Cheyenne20 BB, buckets, tach, tilt, 4 speed 72 jimmy CST wyoming rig 72 jimmy Colorado rig 72 lifted texas 4x4 3/4 ton burb 65 fury conv. 383/auto 65 chrysler 300 "L" 413 auto

03-18-2006, 11:31 PM	#7
sakohntr Registered User Join Date: Mar 2002 Location: Floodwood Minnesota Posts: 1,057	Re: BBC in 4X truck Use all the small block motor mounts and move the whole assembly forward 2 inches. If its a stick you'll have to move the clutch z-bar pivot as well. __________________ 1967 K30 Napco 292/SM420 original paint 30k miles 1968 K60 Napco 396/5spd. dbl frame 52" michelins 1969 K10 SWB GMC 454/4spd 6" 35's posi,hooks 1972 C30 longhorn,BB/AT,A/C,Tilt,Toolbox,lokr 1987 K20 Chevrolet Suburban. 6" lift. 5.7L/TH400 1979 K60 GMC Coleman 4x4, 427/Allison.

03-18-2006, 11:45 PM	#8
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	Re: BBC in 4X truck If you move the rest forward, how does the rear driveline fair? I think my front one can take it but not sure about the rear. Thanks Ror

03-19-2006, 12:45 AM	#9
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	Re: BBC in 4X truck Just got moved here and thought I should add a little info that may help. Its a 72 3/4 4X with an auto. Thanks.

03-19-2006, 06:18 AM	#10
4x4Poet Registered User Join Date: Nov 2004 Location: "Under Montana skies." Posts: 1,836	The BBC is a little longer from the center of the mm to the bellhousing mounting surface, so that should help mitagate moving the whole engine foward. Not that I'm saying that's the thing to do. I'm sure there's a site with BBC vs. SBC dimensions. One can use a 73up crossmember so clamshell mm can be used. Try a search on 4x4 & BBC and crossmember or xmember and some BBC into 4x4 threads should come up. If one moves the z-bar mount foward with the BBC, how does one elongate the pedal rod from clutch pedal to z-bar? Cut, sleeve, and weld? Some one once mentioned using a '70s BBC mech clutch z-bar set up from clutch pedal rod to clutch fork, but I haven't been able to ascertain the reason why or advantage in doing so. If there truly is an advantage. Hydraulic clutch is an option with fabbing and the right bellhousing. __________________ '71 GMC K20 Suburban, '71 GMC K10 Suburban, '72 Chevy C10 CST Suburban, '72 Chevy K20 clunker pickup. Last edited by 4x4Poet; 03-19-2006 at 06:21 AM.

03-19-2006, 11:27 AM	#11
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	Re: BBC in 4X truck Im running a TH 350 auto, hope it holds up, so I dont need to worry about the clutch linkage. I will look at other xmembers though. Thanks for the info.

03-19-2006, 05:32 PM	#12
Yukon Jack Post Whore Join Date: Feb 2000 Location: Rose Hill, KS, USA Posts: 12,683	Re: BBC in 4X truck Welcome to the board and I hope the info I pm'd ya helps you with the swap. I was going to post the article on the 73-8something engine crossmember, but I must have it on my office computer. I will get it posted for you tomorrow. __________________ 1970 Blazer with a 400 sbc and 4" lift 1980 Pontiac Trans Am, 455 Oldsmobile 2012 Kawasaki Concours 14

03-20-2006, 01:15 AM	#13
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,480	Re: BBC in 4X truck [QUOTE=4x4Poet]The BBC is a little longer from the center of the mm to the bellhousing mounting surface. The measurements are identical---small block, big block, 6.2 and 6.5 diesels

03-20-2006, 11:24 AM	#15
Yukon Jack Post Whore Join Date: Feb 2000 Location: Rose Hill, KS, USA Posts: 12,683	Re: BBC in 4X truck Here is the article on the new engine crossmember link 1 link 2 __________________ 1970 Blazer with a 400 sbc and 4" lift 1980 Pontiac Trans Am, 455 Oldsmobile 2012 Kawasaki Concours 14

03-20-2006, 01:38 PM	#16
qksilver Senior Member Join Date: Dec 2004 Location: Southern Pines NC Posts: 3,853	Re: BBC in 4X truck That article make it look so easy............ I have all the later model stuff , I will try it on the second to next project!



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03-20-2006, 08:03 PM	#17
FIVE 0 Registered User Join Date: Mar 2006 Location: Idaho Posts: 84	Re: BBC in 4X truck Outstanding link. Just printed it out. Thanks again for the info. Ror

03-21-2006, 01:10 AM	#18
454_72_4X4 Registered User Join Date: Apr 2004 Location: N.E. MO Posts: 1,749	Re: BBC in 4X truck I'd have to agree. The 73+ X-member would be the way to go. I didn't know about that when I did mine the first time so it sits on the stock 350 mounts and x-member. I "clarenced" the firewall on both sides but didn't have any problems with the HEI. It has all kinds of room, almost 3/16 of an inch! LOL I used the right manifold off of a mid seventies BB pickup and the left was off of a 66 BB car, (Impala I assume). The car manifold has since cracked into 3 pieces and I replaced it with an unkown manifold. I had to remove a little "slice" off of the frame and remodel the engine mount some to get the replacement manifold to fit. BB and SB motor mount dimensions are the same so there's no worries there. __________________ 72 C20 4X4 454 4 speed 89 Trans Am (was) 305 TPI 700r4 93 C1500 2wd Extended cab 350 700r4 98 Sonoma (TPI outa the Trans Am) 03 Yamaha 660 Raptor 03/04 660 Raptor 07 700 Raptor 85 Honda Odyssey

03-23-2006, 06:39 AM	#19
4x4Poet Registered User Join Date: Nov 2004 Location: "Under Montana skies." Posts: 1,836	Re: BBC in 4X truck That link to a 4x4Power mag article is the one I have that I've posted about several times. I don't have a digicam, unfortunately. The BBC radiator shroud shown doesn't look like a 67-72 2wd BBC shroud to me. It looks like a either a 73up shroud or maybe a 2wd SBC shroud. The one in back of the BBC shroud does look like a 67-72 4x4 SBC shroud. __________________ '71 GMC K20 Suburban, '71 GMC K10 Suburban, '72 Chevy C10 CST Suburban, '72 Chevy K20 clunker pickup.

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