Laying out the 72 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Bagd72Chevy · 11-09-2005, 01:44 PM

Hey guys,

My truck is already bagged on 20's (27" tall tires) with air rides control arms and two inch dropped spindles. It lays the crossmember but I think I want to go to the frame.

My Questions are about the front.

I think I'm going to crossmember drop it 1.25 inches to keep stock steering, then Z it 2 inches or so to get that last bit. Will this get the frame down??
Also will I run into problems with the tubular upper control arms and the steering shaft??

Thanks guys,
Ryan

fastbagged68 · 11-09-2005, 03:09 PM

Air out your truck and measure how far off the ground your frame is right behind the firewall. I suspect it to be less then 3 inches. Notch your crossmember 1.25 and Z the difference of it. Unless you plan on running bigger tires that will do. Also check what else hangs below your frame rail....ie your trailing arm crossmember, rivets on the frame...

Another thing...if you can't see under your truck to measure the frame jack it up level and put some 4x12 blocks to get it up off the ground 3.5". Hope this makes sense.

Bagd72Chevy · 11-09-2005, 03:20 PM

Thanks for the reply.

The problem is the truck is on jack stands right now. So I was looking for a round about measurement. When I do it I'll drop the crossmember then mount it and measure for the Z.

ANyone have any idea about the steering shaft??

XXL · 11-09-2005, 10:17 PM

Quote:

Originally Posted by Bagd72Chevy

ANyone have any idea about the steering shaft??

My 1.5" xmember drop required 2 swivel joints in the steering shaft. I doubt 0.25" less is going to eliminate that need.

*...jasper...* · 11-12-2005, 10:13 AM

XXL Am I reading this correct. You cut and dropped your front crossmember 1.5 inches. And other then adding 2 swivel joints to the steering box shaft, thats all you had to do ? I thought you had to do more. Like maybe re locate the steering box. and tie rods to clear. Your steering does not hit your frame ?

XXL · 11-12-2005, 12:45 PM

Quote:

Originally Posted by ...jasper...

XXL Am I reading this correct. You cut and dropped your front crossmember 1.5 inches. And other then adding 2 swivel joints to the steering box shaft, thats all you had to do ? I thought you had to do more. Like maybe re locate the steering box. and tie rods to clear. Your steering does not hit your frame ?

Correct... well, almost, 1.5" CaptKaos crossmember drop, steering box in stock location, _3_ Borgeson u-joints, and voila.

*...jasper...* · 11-13-2005, 10:28 AM

Thanks for the help. Just one other thing. Once when I was at a swap meet I saw a 71 sitting low in the parking lot. I looked under it. And The lower A-frame was bolted up diffrent. The guy was not around so I could not ask. The lower A-frame instead of bolted up by the factory u-bolts to the bottom of the crossmember. There was a plate bolted up to the crossmember were the u-bolts went, then the lower A-frame was bolted up to it. Which let the lower A-frame be on each side of the crossmember and not the bottom. I am sure the reason for this is so the bottom a-frame would be higher off the ground. Is this a bracket that you can buy,or something that has to be made up.

XXL · 11-15-2005, 12:40 AM

Quote:

Originally Posted by ...jasper...

Thanks for the help. Just one other thing. Once when I was at a swap meet I saw a 71 sitting low in the parking lot. I looked under it. And The lower A-frame was bolted up diffrent. The guy was not around so I could not ask. The lower A-frame instead of bolted up by the factory u-bolts to the bottom of the crossmember. There was a plate bolted up to the crossmember were the u-bolts went, then the lower A-frame was bolted up to it. Which let the lower A-frame be on each side of the crossmember and not the bottom. I am sure the reason for this is so the bottom a-frame would be higher off the ground. Is this a bracket that you can buy,or something that has to be made up.

There's nothing bolt-on that does this... except that there are some who offer pre-mod'd xmembers for this. There are several on the board who've done this mod... do a search or read the giant crossmember thread for lots more info.

lvscott · 11-22-2005, 01:44 AM

Quote:

Originally Posted by fastbagged68

Notch your crossmember 1.25 and Z the difference of it.

i was wondering if there is anything that keeps me from just z-ing the frame without notching the crossmember?

SCOTI · 11-22-2005, 11:12 AM

Quote:

Originally Posted by lvscott

i was wondering if there is anything that keeps me from just z-ing the frame without notching the crossmember?

Do a notch if you need a little.
Do a 'Z' if you need a lot.

XXL · 11-22-2005, 08:31 PM

Quote:

Originally Posted by SCOTI

Do a notch if you need a little.
Do a 'Z' if you need a lot.

Actually, if you need a lot, I'd do some of both. With just a Z, you'll be able to get the low-hanging parts on the ground real fast (lower control arms), but you won't be very low visually (relatively speaking, of course... for me, anything that won't stop a golf ball is nosebleed-high

)

lvscott · 11-23-2005, 02:49 AM

Quote:

Originally Posted by XXL

Actually, if you need a lot, I'd do some of both. With just a Z, you'll be able to get the low-hanging parts on the ground real fast (lower control arms), but you won't be very low visually (relatively speaking, of course... for me, anything that won't stop a golf ball is nosebleed-high

)

actually i like the way my truck looks when it is just about fully aired out. but that doesn't leave much room for suspension travel, so i figure if i z my frame 3-4 inches my ride height should be just about right? i hope.

**Captkaos** · 11-23-2005, 01:27 PM

Quote:

Originally Posted by XXL

Correct... well, almost, 1.5" CaptKaos crossmember drop, steering box in stock location, _3_ Borgeson u-joints, and voila.

Thanks for the Props XXL! I keep looking for your truck updates, anything new.

11-09-2005, 01:44 PM	#1
Bagd72Chevy C10 Collector Join Date: Oct 2003 Location: Baton Rouge, LA Posts: 417	Laying out the 72 Hey guys, My truck is already bagged on 20's (27" tall tires) with air rides control arms and two inch dropped spindles. It lays the crossmember but I think I want to go to the frame. My Questions are about the front. I think I'm going to crossmember drop it 1.25 inches to keep stock steering, then Z it 2 inches or so to get that last bit. Will this get the frame down?? Also will I run into problems with the tubular upper control arms and the steering shaft?? Thanks guys, Ryan

11-09-2005, 03:09 PM	#2
fastbagged68 Registered User Join Date: Jun 2002 Location: Tri Valley California Posts: 792	Re: Laying out the 72 Air out your truck and measure how far off the ground your frame is right behind the firewall. I suspect it to be less then 3 inches. Notch your crossmember 1.25 and Z the difference of it. Unless you plan on running bigger tires that will do. Also check what else hangs below your frame rail....ie your trailing arm crossmember, rivets on the frame... Another thing...if you can't see under your truck to measure the frame jack it up level and put some 4x12 blocks to get it up off the ground 3.5". Hope this makes sense.

11-09-2005, 03:20 PM	#3
Bagd72Chevy C10 Collector Join Date: Oct 2003 Location: Baton Rouge, LA Posts: 417	Re: Laying out the 72 Thanks for the reply. The problem is the truck is on jack stands right now. So I was looking for a round about measurement. When I do it I'll drop the crossmember then mount it and measure for the Z. ANyone have any idea about the steering shaft??

11-12-2005, 10:13 AM	#5
...jasper... Account Suspended Join Date: Oct 2005 Location: Riverside Calif. USA Posts: 29	Re: Laying out the 72 XXL Am I reading this correct. You cut and dropped your front crossmember 1.5 inches. And other then adding 2 swivel joints to the steering box shaft, thats all you had to do ? I thought you had to do more. Like maybe re locate the steering box. and tie rods to clear. Your steering does not hit your frame ?

11-13-2005, 10:28 AM	#7
...jasper... Account Suspended Join Date: Oct 2005 Location: Riverside Calif. USA Posts: 29	Re: Laying out the 72 Thanks for the help. Just one other thing. Once when I was at a swap meet I saw a 71 sitting low in the parking lot. I looked under it. And The lower A-frame was bolted up diffrent. The guy was not around so I could not ask. The lower A-frame instead of bolted up by the factory u-bolts to the bottom of the crossmember. There was a plate bolted up to the crossmember were the u-bolts went, then the lower A-frame was bolted up to it. Which let the lower A-frame be on each side of the crossmember and not the bottom. I am sure the reason for this is so the bottom a-frame would be higher off the ground. Is this a bracket that you can buy,or something that has to be made up.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.