Once the general shape has...
Once the general shape has been checked against its counterparts on the other side of the manifold, the welded area is ground and contoured with a die grinder.
Forty years of machining and restoring has presented a lot of opportunities to tackle problems from different directions, and for concours restoration work, Lamar and his son, Rob, needed a way of restoring cast aluminum so it looks like it did when the factory installed it on the cars, rather than when some guy glass beaded it in his garage and bolted it on.
We’ve seen the Waldens repair and restore cracked or broken cast-iron intakes, blocks, and bell housings, as well as aluminum parts, and have spoken with them often about their process for reskinning aluminum. The finish they get runs right in line with what we’ve always thought the finish on factory aluminum parts should be: smooth, dull gray, and not the least bit porous or whitish.
Here you can see the outside...
Here you can see the outside contour of the broken ear has been restored. The repair was left unground where it meets the machined surface at this point.
When you just glass bead aluminum Lamar told us, it opens the pores and absorbs any oil or gas. The open pores also let it oxidize more quickly, Rob adds, which makes them look old and dingy before their time. With Lamar’s reskinning process, the pores on the surface of the part are closed, which not only gives a piece the proper finish and inhibits oxidation, but it keeps the parts from absorbing grease and grime. Cleaning and detailing is as simple as giving it a shot of WD-40 and wiping it off.
He’s understandably protective of the process, so we aren’t showing that final step, but he’s not so proud of the work that he charges ridiculously for it. After a cast aluminum piece comes out of Lamar’s treatment, it looks like it was just poured from good molds at the foundry, rather than looking like a porous metal lava rock.
Once the repairs have been...
Once the repairs have been made, Walden uses a CNC machine to mill the gasket surfaces, dressing the repaired area at the same time.
Their restoration process doesn’t end there, thoughbesides repairing damage and recreating missing sections, they also re-machine the entire gasket mating surfaces, which yielded some surprising results in our opinion: Most intake manifolds are warped now, Lamar says, so they true the surfaces, eliminating leaking gaskets. We had them do an old Edelbrock C3B intake for our daily driver, and the intake gasket mounting surfaces needed to be milled 0.030-inch before it was square again.
Lamar is nationally known as a 409 Chevy guru, so when we asked if he could whip something together for this story, Rob walked to the pile of 409 intakes and found a suitable candidate for us to watch him restore. The one he picked off the top of the pile looked like something found in the woods, but once he was done; you’d swear the thing was N.O.S.
Bead blasting revealed a cracked mounting bolt boss, and just a little effort broke it away. Cracked temp sending holes and pipe plug bosses are also common.
By today, most vintage intakes...
By today, most vintage intakes are warped. This first pass took off 0.002-inch, and cleaned up at 0.005-inch, while the Edelbrock C3B we restored needed 0.030-inch to clean up.
Once the machined surfaces...
Once the machined surfaces are finished, the repaired/filled bolthole is drilled through at the proper angle.
Originally, most bolt bosses...
Originally, most bolt bosses are spot-faced. A spot-face tool plunges down, but intake runners typically are in the way, so Lamar made one that installs from the bottom.
The repaired boss; welded,...
The repaired boss; welded, spot-faced, and the intake is reskinned. You can’t tell the area was ever missing.
The carb pads and thermostat...
The carb pads and thermostat housing surface is machined too. The intake goes through the reskinning process before it is machined on the CNC mill.
The sheetmetal heat shield...
The sheetmetal heat shield is also blasted and reskinned before being reinstalled with the original rivets.
The finished intake is so...
The finished intake is so close to N.O.S. it only needs a factory box to pass for the genuine article. Lamar jammed this one out for us, so he left the hose nipple in.
Waldens will restore anything...
Waldens will restore anything made from aluminum, and can also make invisible repairs to cast-iron pieces like multi-carb intakes and 409 blocks.
This is the factory original...
This is the factory original block from Reggie Jackson’s No. 51 ZL-1 Camaro, originally owned by Lamar. The whole rear corner, including oil filter boss, was gone.