Finally: Full Restomod

[ISPKI]

Driver's side patch panels are exceptionally disgusting. I dont have the right tools to get into the corners so cleaning the rust out before welding was extremely difficult. Hopefully going to have the side of the frame cleaned up by the end of tomorrow.

[1969honda]

I'd definitely try the smaller wire diameter and play with the heat and ipm. I recently welded up some .065" exhaust for my wife's Yukon with .035" and at 14v with something around 120ipm iirc it was still to much wire and burned thru like crazy if I tried to pull a continuous bead, on 1.75 or 3" tubing. It was all new tubing and modifying new raw steel Hooker Super Comp F-body LT headers so new steel all around.

[ISPKI]

On 11/5/2019 at 12:45 AM, 1969honda said:

I'd definitely try the smaller wire diameter and play with the heat and ipm. I recently welded up some .065" exhaust for my wife's Yukon with .035" and at 14v with something around 120ipm iirc it was still to much wire and burned thru like crazy if I tried to pull a continuous bead, on 1.75 or 3" tubing. It was all new tubing and modifying new raw steel Hooker Super Comp F-body LT headers so new steel all around.

Yeah I need to get another bottle for my 140A mig, or a bottle of argon so I can run the Tig side of my multiprocess welder. I did just run out of gas so now may be the time.

Thing is, 95% of what I am welding is thin body sheet metal with piss poor joint fit up. This kind of welding should really only be spot welded anyways so as to reduce warping as much as possible. I should take some shots of the engine bay side of the fender panel, those were much better fitting and cleaner...and I wasnt welding up which always helps.

[Ironhead]

On 11/4/2019 at 9:45 PM, 1969honda said:

I'd definitely try the smaller wire diameter and play with the heat and ipm. I recently welded up some .065" exhaust for my wife's Yukon with .035" and at 14v with something around 120ipm iirc it was still to much wire and burned thru like crazy if I tried to pull a continuous bead, on 1.75 or 3" tubing. It was all new tubing and modifying new raw steel Hooker Super Comp F-body LT headers so new steel all around.

 

I pretty much gave up trying to use continuous beads when welding very thin metal, and use a series of connected spot welds.  With such thin metal, you still get ample penetration, and for me (limited skill level) it is the best way to keep the heat under control.

 

Every place I tried continuous beads on the Datsun sheet metal, it was a shit show...both in terms of burn through and horrible distortion.

[ISPKI]

On 12/25/2019 at 9:36 AM, Ironhead said:

 

I pretty much gave up trying to use continuous beads when welding very thin metal, and use a series of connected spot welds.  With such thin metal, you still get ample penetration, and for me (limited skill level) it is the best way to keep the heat under control.

 

Every place I tried continuous beads on the Datsun sheet metal, it was a shit show...both in terms of burn through and horrible distortion.

Continuous beads (stitch welding) is never a good idea on thin sheet metal, exactly for the reasons you mentioned. Distortion being the biggest issue unless the piece you are working on is extremely well constrained, but most of the times it isnt.

 

On longer runs, I usually will place my spots a few inches apart. If I have enough access and the joint permits, I will sometimes clamp on a copper or aluminum backer plate which seems to sink the heat out of the sheet metal sufficiently so as to avoid distortion even in long stitch runs but automotive application rarely has the space for it.

[ISPKI]

So I have had the Z on hold for a bit this winter unfortunately. Finished up a bathroom in the house and fixing the fueling system on my log truck, but I am back at it!

 

Last night I cut out the driver side floor frame and spent a solid hour in 7 degree temps grinding away the rubber insulation and paint to prep the weld areas for welding. Finished the night test fitting the floor panel.

 

Tonight, I am planning on finishing the weld prep and continue fitting the floor pan.

 

Also taking a slightly different approach to this side. My floor area under the seat rails is actually solid on this side, just a bit of surface rust here and there so I cut up to the flange of the forward rail. I am planning on cutting the floor pan with a 1" tab that will slip under the remaining floor and running a small bead across the bottom of that.

[Jboogsthethug]

Keep up the hard work! You're smart about it all! I did a majority of the welding then painted, not realizing how much I'd change my mind about what I wanted before being done. Now I have to repaint over all the welding haha.

[ISPKI]

On 3/2/2020 at 12:29 PM, Jboogsthethug said:

Keep up the hard work! You're smart about it all! I did a majority of the welding then painted, not realizing how much I'd change my mind about what I wanted before being done. Now I have to repaint over all the welding haha.

 

Thank you! your car in your sig looks fantastic!

 

Been a bit but ive been working hard on the Z. Driver's side floor and floor frame support are welded in. Went a little better than the passenger side, the floor under the seat rails was not rotted the way the passenger side was so I only installed half the floor pan and didnt cut out the cross members, made for alot less work.

 

I also test fit the 302 into the engine bay! I have Brian Layne's engine cradle print and fabricated the materials at work (CNC machining is so much nicer than grinding at home). I have the engine cradle all welded up and it fits beautifully. A little snug, I have to tap it in with a mallet to get it to seat all the way but that tells me its perfect.

 

I wanted to ask people how they have fastened the engine cradle to the frame of the Z? I started by drilling and welding in thread inserts inside the frame but now that ive done a few and have seen how flimsy the frame material is, I wonder if I should go about it a little differently. Here is my thought;

 

Drill thru top and bottom of frame. insert a steel sleeve spanning the ID of the frame and weld it in. Weld a thread insert top and bottom of the tube. Install a long bolt from bottom up (3/8-16 big nuff?) so that it protrudes out the top by about 1/2-3/4" functionally acting as a stud. When threading thru the thread inserts, the bolt should push or pull the thread inserts together, applying compression force to the welded tube inside the frame. That should transfer as much load from the engine cradle as possible. Attached is a drawing of what I am thinking.

[Exposed]

@ISPKI thats pretty much how I did mine but for my sway bar. I drilled out a hole at the top through to the bottom then dropped in the tube sleeve, finished it off by welding and grinding it down. Have it documented on page 11 of my build thread about 1/3 of the way down.

Edited April 6, 2020 by Exposed

[ISPKI]

19 hours ago, Exposed said:

@ISPKI thats pretty much how I did mine but for my sway bar. I drilled out a hole at the top through to the bottom then dropped in the tube sleeve, finished it off by welding and grinding it down. Have it documented on page 11 of my build thread about 1/3 of the way down.

Awesome, glad to know im on the right track.

I made one of the tube inserts last night out of some steel tube that I had laying around. Not super heavy wall but I bet it doesnt really need to be all that heavy. Seemed like maybe 1/16" wall thickness, 3/4" OD roughly. I think the thread insert on both ends of the tube adds a level of complication that isnt really necessary. I ended up having the thread insert on the top, pressed in a nut into the bottom of the tube, then threaded a bolt through both so it protruded out the top by about an inch. I then drilled 1" holes thru top and bottom of the frame and welded the insert into it. The bolt came out smack dab in between the steering rack cross member and the mount for the forward control arm(?), where that heavy rod mounts angularly thru the frame. Seems to be  the strongest spot on the frame. Going to do another one closer to the firewall, 2 horizontally through the frame, and 1 through the steering rack cross member.

[ISPKI]

Here is how the frame inserts look. It was a real pain to weld into the bottom of the frame

[ISPKI]

Arighty. So I spent some time shaving the brackets out of the engine bay, removing A/C lines and what not. I picked up my buddy's load leveller for the hoist and have the engine almost in position. However, the oil pan is touching the engine cradle and the motor mounts still need to come down another inch or so to line up with the cradle.

 

I will have to wait to get it mounted until I can find a front sump or dual sump oil pan.

 

In the meantime, I completed the frame insert tubes for the mounting studs on the driver side. Going to start working on the passenger side this afternoon.

[Jboogsthethug]

What does your engine cradle look like? Is it one of those that bolt up in between the tranny and engine and are basically a big sheet of metal?

[ISPKI]

20 hours ago, Jboogsthethug said:

What does your engine cradle look like? Is it one of those that bolt up in between the tranny and engine and are basically a big sheet of metal?

No, it is similar in design to Brian Layne's motor cradle with some minor tweaks (mostly mounting).

I did not see if he used horizontal mounting points, all I saw in his write up were two top bolts plus one bolt thru the steering cross member. I am going to do 2 top, 2 sides, 1 thru the steering cross member. This is mostly due to the engine that I am working with being much newer and probably capable of putting out a little more power, plus I may procharge it down the road, who knows.

 

Unfortunately, his drawings do not show the depth of the center cross member relative to the top of the side rails. I think mine is not quite as deep as his.

[Jboogsthethug]

oh interesting! Are you going to solid mount that or use some bushings? I could see that being much easier to drop in than what I'm doing (same motor mounts and I just built new mounts on the new engine) ha. Lining up the bolts is a pain for me!

[ISPKI]

21 hours ago, Jboogsthethug said:

oh interesting! Are you going to solid mount that or use some bushings? I could see that being much easier to drop in than what I'm doing (same motor mounts and I just built new mounts on the new engine) ha. Lining up the bolts is a pain for me!

Nah no bushings on the cradle side. The other piece to this is a 2" wide steel "U" that will cross bolt through the 45 angular tubes. That "U" has a 9/16" hole in the top where the motor mounts on the engine will go. Using motor mounts out of a 1983 F150 with a 302. Seem to line up well and are vulcanized rubber mounts so I shouldnt need any bushings frame side.

 

The "U" that Layne used were 3/16" plates folded to shape, mine are 1/4" groove welded on top with a 3/8" fillet weld inside. Should be excessively strong for the application.

 

I have to try and get the engine into position with the "U" brackets bolted onto it, then once it's there, I will need to clamp the brackets to the cradle, unbolt the motor mounts, and then get in there and cross drill a pair of 1/2" bolt holes thru the cradle. Dont think I will weld nuts on the cradle just so I have a little adjustment when finally seating the motor.

 

I dont think I want to do that until I have the transmission bolted to the motor so I can see how thats going to line up and my tranny is missing the bellhousing so that is the item I am looking for currently.

[yellowoctupus]

I'm assuming you are going by these designs:  https://www.lainefamily.com/240Z_V8_Conversion-files/240Z_Conversion_Drawings.pdf

 

From the dimensions shown in his PDF, you should have 6.3" from the top of your frame rails to the top of the lower tube.  (9.103" * sin(45))-(0.187" * sin(45)) = 6.3"

 

 

I have been running a similar design for my supercharged 4.6 for years with two through-frame rali bolts on each side (vertical holes).  No problems, you don't need extra beef.  I didn't even weld in sleeves to keep the frame rails from crushing.  I would allow for the whole cradle assembly to slide front and back to facilitate engine installs.  (don't weld studs in from the top or overthink it generally).  

 

One thing I WOULD do if I were you is add a bolt in plate (I actually thought Brian's design incorporated a bolt in center section) to allow the oil pan to be dropped without jacking the engine off it's mounts, etc. Next time my engine's out i am going to change my design. It's had a minor oil leak for years that I can't be bothered to pull the whole engine/trans etc to deal with.  

Edited April 12, 2020 by yellowoctupus
Antigrammerman strikes again!

[ISPKI]

Yeah thats the design im doin. Good to know about the extra beef. I am going to do one thread insert in the frame tubes and just use a long bolt. That should be good enough and I will be able to remove them if need be.

 

I ended up cutting the center section as my 45 degree tubes werent 45 degrees and the oil pan was bottoming out on the cradle. I reset the angle pieces to ~44.5 degrees, lowered the center tube by 2" and rewelded it. Did one seam inside the tube, then made some heavy 1/4" gussets formed on my anvil and welded those in. I think it should be plenty stout and the engine is resting at .1 degrees on both X and Y axis, should be plenty for the motor mounts to compensate for.

 

I clamped and cross drilled a 3/8" hole in both mounts, locked them together with 3/8" bolts, and then removed the engine. Drilled a 2nd thru hole for a 1/2" bolt and then opened up the 3/8" holes to 1/2". I have the cross member in right now, just waiting to find a bellhousing before I drill the frame mount holes for it.

[ISPKI]

Having a hell of a time trying to install a summit oil filter relocation kit at the moment. Not really understanding how this snap ring is supposed to fit or how these inserts are supposed to line up or how I am supposed to remove the threaded nut from the block.

[ISPKI]

Well, ended up yanking the filter adapter out of the arm that was on the block, turned it down and it ended up working just fine.

Picked up a bellhousing and fork for the T5 and got it bolted on and test fit into the car. Shifter comes thru the trans tunnel about an inch or two forward of the Automatic shifter location. I had studs in the top mounting holes of the bellhousing that were hitting the firewall so it will go back a little bit more once I get bolts in there.