Crazy, I did this exact thing to mine this last weekend also getting ready to clear the new larger tires since my 40s already rubbed like crazy there.
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Saying Good-bye to the 90 and Hello to the 72 Build. NEW:Hidden Exhaust
- Thread starter GRINCH
- Start date
Crazy, I did this exact thing to mine this last weekend also getting ready to clear the new larger tires since my 40s already rubbed like crazy there.
I'm curious why the blue fenderwells went on the inside? Wouldn't it have been a lot less work to leave the original fenderwell connected to the bedside, and then graft the blue one to "stretch" it??? 
GRINCH
1/2 ton status
Either way I had to pull them out to make the cut and move the bottom over 1 rib. Once out, the original had more rust on them than the blue ones.
I saved the other half of the blue ones if anyone is looking to tub out thiers. They are in great shape.
I saved the other half of the blue ones if anyone is looking to tub out thiers. They are in great shape.
GRINCH
1/2 ton status
Not much going on...
Finished prepping the doors. Fixed rust in lower corners, Patched speaker holes, Cut truck doors down to blazer doors, all ready for a lil mud and primer.
Abby say's always wear your safety glasses while in the shop.
Abby say's stay tuned for more!!!
She was watching me trying to figure out where to cut the left side of the firewall to make room for the 500. Seen a post on 67-72 chevy site about it. They did it to a 67. The 67 has the linkage assy mounted on the outside. I think I just need clearance where the clutch rod goes through. Remember an auto is going in.
Finished prepping the doors. Fixed rust in lower corners, Patched speaker holes, Cut truck doors down to blazer doors, all ready for a lil mud and primer.
Abby say's always wear your safety glasses while in the shop.
Abby say's stay tuned for more!!!
She was watching me trying to figure out where to cut the left side of the firewall to make room for the 500. Seen a post on 67-72 chevy site about it. They did it to a 67. The 67 has the linkage assy mounted on the outside. I think I just need clearance where the clutch rod goes through. Remember an auto is going in.
y5mgisi
1 ton status
Hey progress is progress. Good job!
GRINCH
1/2 ton status
I can’t believe the way time is flying by and I’m not getting much done. I used to be really good at body work but this one is kicking my a$$. There is more icing on the floor than on the truck. OCD sucks.. I keep telling myself it’s a trail rig and not a pavement queen… Both rear quarters were really smashed in.
I hope to primer it in a week or two.
After primer comes the cage.
It’s time to start thinking about lift. My goal was not to have any at all, Those are 37”s in the pictures. I have a 1” body lift. I cut both the front and rear fenderwells and reshaped them to retain some of the stock look.
So what do you think?
A. 1” zero rates and stock springs. Bumpstops
B. 2” inch lift all around still with zero rates to move axles
C. Custom springs with 3” lift.
Hey Greg, Time to bring back the original post on gearing and open it up for discussion for other to benefit.
I hope to primer it in a week or two.
After primer comes the cage.
It’s time to start thinking about lift. My goal was not to have any at all, Those are 37”s in the pictures. I have a 1” body lift. I cut both the front and rear fenderwells and reshaped them to retain some of the stock look.
So what do you think?
A. 1” zero rates and stock springs. Bumpstops
B. 2” inch lift all around still with zero rates to move axles
C. Custom springs with 3” lift.
Hey Greg, Time to bring back the original post on gearing and open it up for discussion for other to benefit.
bp71k5
3/4 ton status
No discussions about gears until you post more pics on how you modified the wheel wells.
y5mgisi
1 ton status
As much as im sure you dont want to hear it, I would have to say custom springs. That way you get the lift you need and the axle positioning you need with out having to use zero's or having to move spring hangers. And correct me if im wrong but i bleive that year(69-72 or whatever) used an even shorter front spring like 45" or something. So you could do customes with like an inch longer main leaf to help with that issue as well. Any way thats all. I cant wait till i have a garage and can get my OCD on with some body work!
Dennis,
Those fender mods look slick, but I'm concerned that you haven't gone far enough on the front fenders...
With a leaf-sprung suspension and shackle, you get a LOT of tire movement toward the back of the fenderwell as the suspension travels upwards. It always catches people off-guard how much clearance is actually needed to prevent rubbing/crushing the fender with the tire.
Before you spend too much more time on those front fenders, it might be wise to get your suspension figured out and set your final ride height....you'll need the weight of the engine/trans/xfercase to be on those springs also.
A couple of things that might help:
- Move axle forward 1 - 1.5"
- Use stiffer, low-lift springs
I know you've seen this photo before, but it's worth pointing out some things about it...
The axle is moved forward 1" in this photo. It helps to provide extra clearance at the rear of the opening for the shackle movement. Also, if you drop a plumbline from the front edge of the opening, it would actually hit the tire!! You'd assume that there's no way the tire could articulate without crushing the front of the wheelwell, but in actuality, by the time the tire gets up that high, it's already MUCH further back in the wheelwell and nowhere near that interference point anymore.
I guess my point is don't take the truck all the way to final paint before you actually flex it out to check clearances....it could be a real heartbreaker.
Those fender mods look slick, but I'm concerned that you haven't gone far enough on the front fenders...
With a leaf-sprung suspension and shackle, you get a LOT of tire movement toward the back of the fenderwell as the suspension travels upwards. It always catches people off-guard how much clearance is actually needed to prevent rubbing/crushing the fender with the tire.
Before you spend too much more time on those front fenders, it might be wise to get your suspension figured out and set your final ride height....you'll need the weight of the engine/trans/xfercase to be on those springs also.
A couple of things that might help:
- Move axle forward 1 - 1.5"
- Use stiffer, low-lift springs
I know you've seen this photo before, but it's worth pointing out some things about it...
The axle is moved forward 1" in this photo. It helps to provide extra clearance at the rear of the opening for the shackle movement. Also, if you drop a plumbline from the front edge of the opening, it would actually hit the tire!! You'd assume that there's no way the tire could articulate without crushing the front of the wheelwell, but in actuality, by the time the tire gets up that high, it's already MUCH further back in the wheelwell and nowhere near that interference point anymore.
I guess my point is don't take the truck all the way to final paint before you actually flex it out to check clearances....it could be a real heartbreaker.
GRINCH
1/2 ton status
I had some pics of the steps but now I can't find them. It wasn't really that hard. I just short of eye balled the angle I wanted with tape and then took out a pie shaped piece. Stay at least a 1/4" away from the edge so when it's welded back together you a some of the original metal exposed. Makes shaping the mud easier. Take out a smaller piece of the pie at first. As you are pushing the edges together after the piece is removed you may have to take a little more. Make a pattern of the piece so you can duplicate it on the other side. Flip it over. Sounds harder than it is.No discussions about gears until you post more pics on how you modified the wheel wells.
Dennis,
Those fender mods look slick, but I'm concerned that you haven't gone far enough on the front fenders...
The axle is moved forward 1" in this photo. It helps to provide extra clearance at the rear of the opening for the shackle movement. Also, if you drop a plumbline from the front edge of the opening, it would actually hit the tire!! You'd assume that there's no way the tire could articulate without crushing the front of the wheelwell, but in actuality, by the time the tire gets up that high, it's already MUCH further back in the wheelwell and nowhere near that interference point anymore.
I guess my point is don't take the truck all the way to final paint before you actually flex it out to check clearances....it could be a real heartbreaker.
My thoughts too. I really couldn't take out much more of the fang without distorting it really bad. I want to retain as much of my inner fender as possible. I have been thinking about taking more from the back of the front fender. I need to see how it will affect the inner fender. I have always planned on moving the axle forward some. I guess it all depends on my springs and shackle length on how much it moves backwards,
The front springs are 44" eye to eye. I think I am going to go the custom spring route.
Did this for my Son a while back. Many hours on the body work.
Any opinions on National Spring, ALCAN, General or Deaver? I am thinking just a 2" lift all around. I know a rear squatting K5 doesn't look as good but they (IMHO) handle and do better off road. If I don't like it I can always add a zero rate.
Did I mention I have a 14SF for the rear and a 60 for the front?
Last edited:
Why are you going with a semi floater instead of a full floater? Never liked the idea of a tire walking away if you break a rear shaft
GRINCH
1/2 ton status
Cause I already have 2 of them. Both have 4.10 gears. One is in my rolled Blazer that is for sale and if it doesn't sell it's already to bolt in. E-locker, Superior axle shafts and disc brakes included. They are lighter and more ground clearance. Max I'm going to run is 37"'s and most of my playing is in the Snow.. I feel pretty confident I won't break one... But you never know!! With the E-locker it becomes an open diff at the push of a button.
Got it, I would run built one if I had one over finding/paying for a stock FF any day. Keep the pics coming
GRINCH
1/2 ton status
More updates:
Most of the body work is done.
Since I'm going with a danhard heater. http://www.danhard.com/sub2.htm
I closed up the firewall holes.
I also need to make clearance on the passenger side for the Cad 500 to clear.
What is this and what was it for? Stock? (Behind drivers seat)
I think I have decided to go with Tuff Country springs. I'm going to run a 2" lift. I'm going to get the HD springpack for the front. Not only because of the Cad 500. (Really only weighs 50# more than a SBC) but because of the winch bumber and winch, dual batt etc....
While I'm waiting for the springs to arrive I need to finish cleaning up the frame and undercarriage.
Most of the body work is done.
Since I'm going with a danhard heater. http://www.danhard.com/sub2.htm
I closed up the firewall holes.
I also need to make clearance on the passenger side for the Cad 500 to clear.
What is this and what was it for? Stock? (Behind drivers seat)
I think I have decided to go with Tuff Country springs. I'm going to run a 2" lift. I'm going to get the HD springpack for the front. Not only because of the Cad 500. (Really only weighs 50# more than a SBC) but because of the winch bumber and winch, dual batt etc....
While I'm waiting for the springs to arrive I need to finish cleaning up the frame and undercarriage.
bp71k5
3/4 ton status
I believe the spring was used to hold the factory hydraulic jack and the lug wrench.
I can't imagine actually needing an extra heater in mine. The giant 350 ci heater in the front burns my feet throught the floorboards on long summer drives.
I can't imagine actually needing an extra heater in mine. The giant 350 ci heater in the front burns my feet throught the floorboards on long summer drives.
GRINCH
1/2 ton status
It get's a little colder here in Montana... I still have snow at my house!!
I was actually really impressed with my 71 heater. i never took it off and checked/cleaned it out and with the poorly insulated soft top and holes in the floors all over the last trailride it took we went through a blizzard in some low mountains and we stayed perfectly comfortable.
GRINCH
1/2 ton status
Let’s pickup back up on the gearing issue for this build.
First;
The main purpose of the rig is for Snow wheeling. I want the gearing low enough to be able to crawl on top of the snow with little tire spin.
I also want to be able to use it for sand/dirt drags. 100 Yard track
I will be purchasing a STAK t-case with one of the following options
1.0 , 2.10, 3.75
Or
1.0 , 2.43, 4.33
Or
1.0 3.05, 5.44
I am leaning more toward the 2.43/4.33 since I may be able to use the 2.43 range for the drags and some of the snow runs.
I currently have my axles (60/14) set up with 4.10 gears. I am not opposed to changing them out. I have to pull the carriers to put the lockers (Eaton Elocker) in both any way.
The motor will be a Cad 500 producing a Minimum 400 HP and 550 Ft Torque. It will be hooked up to 400 Tranny.
I may convert the 400 to a switch pitch which allows you to run two different stall speeds at a flick up a switch. Meaning I could launch on the 4000 (or 3000) stall and switch it to the low stall for more MPH at the end of the track. This can be setup to do automatically also.
Another option right now is to change out the planetaries in the 400 from 2.48 1st and 1.48 2nd to 2.75 for 1st. This may be too low and also increases the spread between 1st and 2nd. Like the problem I had with my 700R4 with 1st at 3.06 and 2nd at 1.63
I did consider the 4l80E but the cost would really hamper the build budget. But it would give me OD which could be used on the street as well as at the drags.
I will be running either 36" or 37" tires.
Since the STAK is at least 6 weeks out for delivery I need to get it ordered ASAP.
Here is what Greg and I were working on a while back (Thanks Greg)
Here are some calcs to help you along on your new build (the '72K5)... I wanted to make sure that this data ends up in a searchable forum so that others can benefit from this effort too...
Take a look at the following data. I'll make a few observations, then we can pick up the discussion in your new build thread when you create it.
Going from a 700R4/241 setup to a TH400/Atlas4 (or STaK) box may end up being a good solution for your snow wheeling, but may work against you a bit on the sand drags.... this is more a function of the TH400 selection than the Atlas, because you're losing the deeper 1st gear ratio (3.06 vs. 2.48) and you also lose the ability to run in OD to pick up more MPH at the big end of the track.
Although you don't run many highway miles, the TH400 will punish you more in fuel consumption and engine RPM as well (obviously) without the OD.
Take a look at the data, and start your new thread. Once you do, we can post this chart over there too and get into the numbers more deeply....
So what gears to run in the axle and what to order from STAK?
First;
The main purpose of the rig is for Snow wheeling. I want the gearing low enough to be able to crawl on top of the snow with little tire spin.
I also want to be able to use it for sand/dirt drags. 100 Yard track
I will be purchasing a STAK t-case with one of the following options
1.0 , 2.10, 3.75
Or
1.0 , 2.43, 4.33
Or
1.0 3.05, 5.44
I am leaning more toward the 2.43/4.33 since I may be able to use the 2.43 range for the drags and some of the snow runs.
I currently have my axles (60/14) set up with 4.10 gears. I am not opposed to changing them out. I have to pull the carriers to put the lockers (Eaton Elocker) in both any way.
The motor will be a Cad 500 producing a Minimum 400 HP and 550 Ft Torque. It will be hooked up to 400 Tranny.
I may convert the 400 to a switch pitch which allows you to run two different stall speeds at a flick up a switch. Meaning I could launch on the 4000 (or 3000) stall and switch it to the low stall for more MPH at the end of the track. This can be setup to do automatically also.
Another option right now is to change out the planetaries in the 400 from 2.48 1st and 1.48 2nd to 2.75 for 1st. This may be too low and also increases the spread between 1st and 2nd. Like the problem I had with my 700R4 with 1st at 3.06 and 2nd at 1.63
I did consider the 4l80E but the cost would really hamper the build budget. But it would give me OD which could be used on the street as well as at the drags.
I will be running either 36" or 37" tires.
Since the STAK is at least 6 weeks out for delivery I need to get it ordered ASAP.
Here is what Greg and I were working on a while back (Thanks Greg)
Here are some calcs to help you along on your new build (the '72K5)... I wanted to make sure that this data ends up in a searchable forum so that others can benefit from this effort too...
Take a look at the following data. I'll make a few observations, then we can pick up the discussion in your new build thread when you create it.
Going from a 700R4/241 setup to a TH400/Atlas4 (or STaK) box may end up being a good solution for your snow wheeling, but may work against you a bit on the sand drags.... this is more a function of the TH400 selection than the Atlas, because you're losing the deeper 1st gear ratio (3.06 vs. 2.48) and you also lose the ability to run in OD to pick up more MPH at the big end of the track.
Although you don't run many highway miles, the TH400 will punish you more in fuel consumption and engine RPM as well (obviously) without the OD.
Take a look at the data, and start your new thread. Once you do, we can post this chart over there too and get into the numbers more deeply....
So what gears to run in the axle and what to order from STAK?
Last edited by a moderator:
bp71k5
3/4 ton status
I suspect if you have the deep gearing your talking about in the transfer case, you won't need more than the 4.10's in the axles especially with the big motor and an auto tranny.
