Chassis Stiffening - Driver's Side

After the Long was patched up, I added a further skin to stiffen the chassis - inline with the passenger side. Paint removed, metal cleaned up...

..and weld primered.

The Jack Post area was plated first in two halves of 1.5mm steel with curved upper and lower edges to fit perfectly against the Long beneath.

I drilled the plate that sits on the angle of the Long and removed the paint around the holes..

All 3 pieces were tack welded in place..

 Welds were finished, cleaned up and ground smooth-ish..

Jack Post & Long Repair - Drivers Side

Like the passenger side, the driver's side Jacking Point was in need of some love. So I cut-out the original one and removed the worst of the rust.

I made a point of marking the position of the Jack Post so I know exactly where to position the replacement part.

8mm holes were drilled out around the edge of the cut-out to patch-in a plate on the inside of the Long itself.

The inner plate (1.2mm) was plug welded using the drilled holes..

This inner-plate gave me something to weld the second layer to. The bottom edge of the Long was fine so I just needed to put a single bend in the patch (1.5mm) to fill the top curve of the Long. The holes are obviously for me to plug-weld it to the inner-plate..

Then it's just a case of fully welding the patch in place and then grinding it smooth. I could have stopped here, but because of all the additional stiffening I'm doing to the chassis, I decided to add another layer. I'll show this in the next post. This thing ain't going to flex at all!

Firewall Patch

The Firewall separates the cabin from the engine bay. It has sound & heat-proofing material glued to the engine side which can trap moisture and start rust. This car's firewall has a few holes that need patching. Here's one done...

Here's the hole I cut out to fill...you can see how pitted the piece was that came out of it below.

Here's the replacement piece I fabricated..

 Held in place with Intergrips..

Tack welded, then fully welded. After all this, I ground it smooth and primered it.

914 Maddog Inner Long Chassis Stiffening Kit - Grind and Primer

After loads of welding, it's time to grind the welds smooth-ish and get some primer on them. So that's exactly what I did! I didn't grind the welds flat but I took them down to a level where they wouldn't be noticeable beneath a carpet..if indeed I do carpet the interior.

Here's the driver's side.. 

Lower Firewall left.. thrilling!

More shiny metal!! Lower Firewall right..

The Longs: Driver's..

Passenger's..

...and after plenty of wire-brushing and degreaser, it's time to lay down a nice coat of tough 2K Epoxy Primer. I've got some new stuff made by Lechler which is lovely and smooth. I never thought I'd feel strongly about paint(!) but this stuff, dare I say it, is alot nicer than the stuff I got from Rustbuster and was alot less expensive too....does anyone care?? I should go on 'Watchdog'! Here's the passenger side sprayed up in RAL 7035 Light Grey.

914 Maddog Inner Long Chassis Stiffening Kit - Weld

So to start welding.. It was important to really keep the heat to a minimum so I really took my time doing this. I cooled each weld with compressed air and avoided welding in the same area for too long. I'd weld on one side for 3 or 4 plug welds then move to another area.. For the bead welds I'd do an inch then cool it with the compressed air. It goes without saying that it's a very good idea to brace the door opening to help prevent it from distorting during the welding.

Here's a shot of the Firewall corner. You can see where the screws have been removed; these can easily be filled with weld. I'd only take the screws out when there were plenty of close welds to hold the plate tightly in place.

Here's the Driver's Long. You can see the indent for the handbrake. The metal needs to be hammered in this area to fit snugly.

Here's the welding of the firewall section pretty much finished. There's a ton of welds here because of the extra holes I drilled. You can probably make out the separate inch long beads along the edges.

Here are the beads along the top edge close up.

I wouldn't remove the screws until it's pretty much surrounded by the welds, but then that's just me being ultra-careful!

Work in progress! You can see the door braces..

I cut off the bottom edge of the sections so I could weld them to the Long itself. You can see the short separated beads. I guess you don't really need to do this but I figured it might add a bit of stiffness and I'm also thinking I may not put carpets in the cabin so finishing the edges cleanly like this just made sense visually. ** ref comment below.

More details....

 ...and more...

..and job done!

** See far right of picture above and picture below. I decided to take the opportunity to better weld the actual Long to the outside of the wheel arch. The factory welding is sketchy at best and I thought a bit of extra welding would be a good idea to strengthen the join... If you do this, be aware there's a nice load of weather proofing 'tar' on the other side of the metal which will happily go up in flames if you're not careful!!

914 Maddog Inner Long Chassis Stiffening Kit - Prep

Knowing I'm going to be putting alot of power through this chassis and after a bit of research and advice from the great folks at 914World.com I decided to weld-in reinforcement to the Longs inside the cabin. I bought the 3 piece kit from Maddog Motorsports http://maddogsmotorsports.org

Here's what you get in the kit.... 2 folded sections that go inside the main Longs and a flat plate that connects the sides along the base of the firewall.

I spent time prepping the three sections. They had a good deal of Black Oxide covering them which I removed with a Strip Disc on an Angle Grinder. I've found in the past that it's more difficult to weld through the oxide, you get alot of spatter and the weld isn't as clean - I guess it could be contaminated with the oxide....so best spend the time and effort removing it I reckon. You can see the oxide on the right of the pic below...and the shiny stripped metal to the left.

The holes in the sections were roughly 6mm diameter but I decided to drill them out to 8mm for a little extra strength. I also drilled a number of extra holes which I felt would add a degree of strength and stiffness. As soon as the sections were stripped and drilled, I sprayed them with Weld Thru Primer to prevent re-oxidation..it can happen pretty quickly!

Obviously I needed to strip the Longs and Lower Firewall of paint and clean them up ready for welding. Here's some more shiny pics of the Longs ready to be welded onto..I forgot to take a pic of the Lower Firewall...doh!

...and sprayed with Weld-Thru primer.

It was worth taking the time to fit the sections carefully into place with self-tapping screws. The screws obviously hold the sections really closely against the car to help create solid welds and get maximum reinforcement.

Here's the Lower Firewall section screwed into place..

A little bit of hammering and bending is needed to get the sections to fit in certain areas - such as the handbrake recess, firewall corners and centre...see pic below. I got a bit carried away and decided to clean out the weld-thru primer in the holes with thinners. I reckon you get a better, stronger weld when welding directly onto bare metal..hopefully I'll only have to do this job once..oh yeah, make sure the thinners have completely dried before you start welding!!!..

Tangerine Racing - Suspension Ear Re-Inforcement

Having re-inforced the outer suspension console, I needed to do the inner one - often referred to as the suspension 'ear'.

When I cleaned it up I realised there were a few rust holes which I welded up before welding on the re-inforcement piece.

This is the part from Tangerine Racing. Cleaned up and weld primered..

Here it is welded into place and 'tidied up' with the grinder post welding. Not the easiest thing to weld neatly! But it works...

Before painting it with Epoxy Primer I gave it a final going over with a cup brush on the grinder..and look what I unearthed..a lovely big hole on the underside of the ear. Had I not found it I suppose the suspension could have folded under heavy loading ...

 

...so I closed it up with with what could be described as a welded 'dog's dinner'! To be fair it was really tricky welding in this tight corner, especially upside-down. I think that should be strong enough now!

I should just mention, I also decided to weld all around the edges of the ear for extra rigidity.

More holes on the other side of the ear, welded closed..

..and the whole thing gets a liberal slap of primer, ready for the next 40 years.