67-72 BigBlock 4x4s! Pos pics info here.

[green724x4]

I just wanted to see how many people were doing BBC engine swaps in thier 67-72 4x4s. And did you have valve cover/distributor fire wall clearance issues.
Lets see some pics.

[green724x4]

Ttt

[jerry moss]

my cousin has a 72 chevy 3/4 ton 4x4 that HAD a big block installed when it was almost new back in '72. it was a hack job supposedly done by a local dealership.. they cut the frame rails for exhaust clearance and beat the firewall for clearance and cut the frame for power steering pully clearance. we yanked it out and reapired their screw ups then put a small block back in it. i had a 69 that had a big block hacked into it at one time that took a lot of work to bring back to normal.
i've seen a few 4x4s with big blocks installed that were done very nicely and looked factory, i guess it just depends on who does the install.

[eedgell]

I have a '71 with a 454 complete with new badges. The engine is snug for fit, but no dents in the firewall, or cuts to the frame. My stock exhaust manifold might have helped some for the frame. Stock engine mount locations were used as well. I am running 3:07's with a sm465, with 35's, and really like the combo. 60 miles an hour @ 2000 rpm. It is like overdrive without the OD. The 454 has plenty of torque on the bottom to over come the tires and gear. No replacement for more displacement.
http://67-72chevytrucks.com/vboard/a...1&d=1192915029

[green724x4]

Gotta love the Olive Green!i
Iam looking into a 427 BB for my swap.

[too much stuff]

When i did mine over 10 years ago, i used stock 77 gmc 2wd exhaust manifolds but i had to grind the little nubs off. Also used the original 350 engine mounts. I put on the corvette style valve covers to get a little more clearance by the firewall, but had to grind just a little off the back lip on the drivers side. When i do it next time, i will go with a smaller dist. like a unilite, or mallory. The stock HEI is against the firewall right now. Everything was pretty tight, but it all went. I think i put a small dent in the firewall where the HEI sits. I hear a body lift makes it easier, or i know a guy that moved everything forward to the next set of holes in the frame. Eric

[1969k10stepside]

If you are going to move the motor forward for clearance and are worried about the fact your driveshafts will need to be lengthened and shortened,think of putting in a 700R4,it is about 2" longer than a SM465/NP205 or a TH350/NP205 so you can move the motor forward 2" and add that and keep the driveshafts as they are now.Plus now you've got overdrive.

[eedgell]

Why do some trucks that under go the "knife" for the BB implant have to beat the firewall, cut the frame, or move the mounts forward? While others go through this process without a scratch? They are all the same body, and frame, no?

Originally Posted by 1969k10stepside

If you are going to move the motor forward for clearance and are worried about the fact your driveshafts will need to be lengthened and shortened,think of putting in a 700R4,it is about 2" longer than a SM465/NP205 or a TH350/NP205 so you can move the motor forward 2" and add that and keep the driveshafts as they are now.Plus now you've got overdrive.

[1969k10stepside]

Well,the body mount condition,motor mount,and transfer case mounts do play a role.A worn out mount on one may cause a clearance issue as one that has new bushings doesnt.Valve covers,different distributor,etc also play a role.

[Yukon Jack]

Originally Posted by eedgell

Why do some trucks that under go the "knife" for the BB implant have to beat the firewall, cut the frame, or move the mounts forward? While others go through this process without a scratch? They are all the same body, and frame, no?

I've wondered that ever since I did the swap as I had major firewall clearance issues. I used all new polyurethane mounts when I swapped in the bbc and added a body lift. For some odd reason I had to make the radiator body lift pucks 1" shorter to and it appears my cab does sit a little angled and I'm sure that didn't help my firewall clearance issue.

I would like to address this issue this winter, may move the engine forward, not sure yet. Another option saw done was to drop the engine crossmember 1" - I might do a combination of things.

Here are some pics of the mods I had to make. I was stupid and didn't prefit everything before I took my truck, in pieces, to the body shop. Really couldn't take the truck back home very easily to address the clearance issue so out came the cutoff wheel to make room.









Some people have used a later model engine crossmember but I'm not sure why that helps. Maybe it sits the engine lower, I don't know.

[too much stuff]

Here are a few pics of how mine is sitting right now. Let me know if you have any questions or want more pics, Eric
Also, can't remember what combonation of brackets i used to make the power steering work, but it works!!

[68,69 K20]

I'm glad this topic comes up from time to time as I have been toying with the idea of putting a big block in my 69 K20. I dont want to do it if it means messing with the frame rails, hacking up firewall, etc.

eedgell, love that truck man!!! The BB swap looks like it could have been factory done, nice job!!

What year BB's are you guys running? 2wd exhaust manifolds? Any oil pan clearance issues? Any info you guys who have done this swap have and would like to share would be great, thanks, Mike.

[Yukon Jack]

I'm running 73-?? 4wd headers on mine by Dynomax. My oil pan clearance using my stock crossmember was very close so I used a couple washers between the block and the engine mount to raise the motor up slightly. My bbc is a 1989 454 from a C30 so it has the truck oil pan.

I did have to grind a little off my passenger side frame rail to make the headers fit.

[Burt4x4]

Here is my 454 before I put it in.

Took the front clip off to make things easier.

I painted everything black so the pics are kinda hard to see...

You can see the firewall bashing I had to clear the driver side cover.

Pass side Thorley header clearance...the second tube from the front is about 1/8" from the frame, my buddy put a small 1/2moom cut in his frame but I didn't need to but prolly should have for CYA to keep it from hitting when flexing.

I am using a small Malory EFI dist so clearence is not an issue. Plus I have a 3" body lift.

This is a shot of my new cog belt setup & the 73+ crossmember I used (gone now).


I put in an ORD 73+ crossmember cuz the factory 73+ one I put in cracked. This is a much stronger way to go.. www.diy4x.com makes a firstgen crossmember that pits better, not so close to the oil pan, DIY wasn't making them the time I did mine so OR was my only choice at the time.

as you can see the ORD is very very close but not touching....

Gotta love the power of a 454

[BurnoutNova]

dang.... i should do this. i even have a 71 dated 402 and all the factory a/c & p/s brackets to make it work too...

hmmm

[Burt4x4]

Originally Posted by BurnoutNova

dang.... i should do this. i even have a 71 dated 402 and all the factory a/c & p/s brackets to make it work too...

hmmm

Rebuild that BBC and doit The lowend torque is awesome, I can wheel with my feet on the floor and the rig just keeps motoring up and around at idel corse its fun to punch-it too

[green724x4]

My progress has been slow but I am getting there.Ready to pull the tired 350 out.

Burt 4x4 how much did the thorley headers run you, what part # and how is the ceramic holding up. Which mallory distributor is that.
Has anyone else did a BBC swap in there 67-72 since.
I really want this to be a helpful source for some one who is thinking about doing it.

[Burt4x4]

Thorley = 304-Y I think I paid $325 from Summit..been a wile now..
Here is a pic I found that shows the color of the heders after about 700 miles or so:

Dirt/water/mud/rain & HEAT = faded


Mallory 6148201
This dist. is built to work with Edelbrock Pro-Flo MPFI = the plug on the dist matches the plug on the Edelbrock FI harness. The small cap design is great for firewall clearance!

[Truck Hippy]

This is a shot of a truck I had back in '95 that I put a 454 in. Its a '72 swb 4x4 that was loaded. I put the 454 in without any firewall, frame, or other mods. I pulled this engine out and put in an orginal 402 about one year later. While the engine was out, I noticed the lip on the valve covers rubbed the firewall on each side during engine movement so before installing the 402, I took a hammer and just tapped the firewall on each side. Only just enough to provide room for the engine to move without touching. I may have been able to tweek the valve covers but I didn't try.

[BurnoutNova]

is that a 67-9 camaro in that last picture?

[Truck Hippy]

You have a very good eye, lol. Thats a '68 camaro that I raised cain in with several big blocks while I had it.

[BurnoutNova]

Originally Posted by Truck Hippy

You have a very good eye, lol. Thats a '68 camaro that I raised cain in with several big blocks while I had it.

the more i looked at that pic the less confident i got that it was a first gen camaro, lol. i kinda like trying to guess what stuff is in the backrounds of pictures

[BurnoutNova]

you still have either the camaro or the short K10? that K10 looks like a badass ride, the mopre i look at these thing the more i want to yank the 350 out of my K10 and put my 402 in. damnit i need to quit looking at this site i end up tearing more stuff apart after i sit here and watch everyone else do it, lol

[Truck Hippy]

Originally Posted by BurnoutNova

you still have either the camaro or the short K10? that K10 looks like a badass ride, the mopre i look at these thing the more i want to yank the 350 out of my K10 and put my 402 in. damnit i need to quit looking at this site i end up tearing more stuff apart after i sit here and watch everyone else do it, lol

I only wish I still had them. The Camaro got swapped a few years after this pic and the truck was sold in '98. The truck was a factory super and was my favorite color, orange. It had tilt, tach, a/c, hooks, am/fm, posi, and dual battery. I have had alot of 4x4's but this one I regret selling.

[BurnoutNova]

if everyone knew they'd be so desireable they wouldnt have been so desireable now.. lol it doesnt make scence but some of them have to be sold, wrecked and rusted away before the others become scarce