BUILD-OFF CHALLENGE: Tygaboy's '75 LS3, It seemed a good idea at the time... Options

[Cracker]

Something else to consider when designing your structure...Foley was sharing with me recently the importance of designing towards keeping the longs from twisting. However, you have a hot-rod - not a race car. Keep that in mind too so as to not over-build. Clean would be sweet - the less you see and only the necessary installed.

Tony

[tygaboy]

CHASSIS STIFFENING: Inner Longs

Got started on the inner long stiffener. Since I deleted the heater tubes, I'm going to skin the long "everywhere". And trying to keep it tight. I like the clean look!
Given the way the longs change shape behind the firewall, I'm planning to make each side in two pieces: the part seen here, and the second part for the "up the long" part.

That part will be more complex and I'm going to have to wait til I cut the suspension consoles out to prep for the Tangerine Racing raised pick up kit.

[tygaboy]

Details, details... trim to fit - even the little weep hole thingy.
Yes, it'll be hidden under carpet but I know it's the way I wanted it. (IMG:style_emoticons/default/shades.gif)

[Mueller]

CHASSIS STIFFENING: Inner Longs

Got started on the inner long stiffener. Since I deleted the heater tubes, I'm going to skin the long "everywhere". And trying to keep it tight. I like the clean look!
Given the way the longs change shape behind the firewall, I'm planning to make each side in two pieces: the part seen here, and the second part for the "up the long" part.

That part will be more complex and I'm going to have to wait til I cut the suspension consoles out to prep for the Tangerine Racing raised pick up kit.

I too like that clean smooth look.

[tygaboy]

Fitting the left side... This went way faster as I was able to use the right side as a template. Just laid them back to back, traced then cut. Done and done!

[Rand]

Nice. You don't need a bunch of tubage. This alone is going to make a big difference.

How are you handling the ebrake?

[tygaboy]

Another. And if you need to make large holes for things like seat belt mount in an inner long stiffener, use a knock out punch! (Crappy pic, in terms of showing that, I know.)
I treated myself to a set of KO punches from Swag Offroad and they're awesome. I use a HF hand hydraulic pump and wow. Super clean, accurate, etc.
I also got their dimple die set which I plan to employ on some of the tunnel and roll cage gussets. Pics as I get to that.

[tygaboy]

Artsy shot of the day. I just love the smooth, clean look! Now to mess it all up with hole drilling and plug welding. Ah well, it'll get covered up at some point anyway.

[tygaboy]

Nice. You don't need a bunch of tubage. This alone is going to make a big difference.

How are you handling the ebrake?

I have a ebrake handle from a 993, so it'll be center mount. A couple of us are going this sort of direction - take a look at 914forme's build, post 291.

[Rand]

Nice. You don't need a bunch of tubage. This alone is going to make a big difference.

How are you handling the ebrake?

I have a ebrake handle from a 993, so it'll be center mount. A couple of us are going this sort of dirtection - take a look at 914forme's build, post 291.

Nice. That's a mod I've thought a lot about. Keep going man, you have a killer build happening!

[Cracker]

Your picture reminds me of a Fred Flintstone mobile...missing floor and all! As always Chris - the work looks fantastic. You better slow down as most projects take decades - you're going to hurt some feelings at this pace!

Tony

Another. And if you need to make large holes for things like seat belt mount in an inner long stiffener, use a knock out punch! (Crappy pic, in terms of showing that, I know.)
I treated myself to a set of KO punches from Swag Offroad and they're awesome. I use a HF hand hydraulic pump and wow. Super clean, accurate, etc.
I also got their dimple die set which I plan to employ on some of the tunnel and roll cage gussets. Pics as I get to that.

[tygaboy]

CHASSIS STIFFENING: Lower Firewall

Today's realization is that this really is a jigsaw puzzle. And I've determined I want to have all the pieces before I start putting any of it together.

So... My stiffening plan includes a tunnel from the firewall to the front roll hoop. Since this will tie into the lower firewall and it's all the way out, this is an opportunity to beef up that area of the chassis, too.

I was planning to run a bar across from long to long and sandwich that between the stock inner and outer firewall sheet metal. But with some additional head scratching and input from my race car fab buddy, Martin, I've decided to build a more substantial structure. Similar to what MichiganMat has done on his build.

If you haven't figured it out yet, I love curves. Arches are pretty strong, too.
Roll bender to the rescue! This is a different one from the one I used to roll the round tube. It's purpose build for flat/square stock. I got it for free and it saves me buying additional dies for the Swag Offroad roll bender.

So instead of running a straight tube across and running sheetmetal from the upper firewall down to the tube, I'm going to roll a square tube that fits right up against that curved lower edge.

First, I used the curve template tool to capture the radius I need. I was surprised at just how much arch there is.

[tygaboy]

Then it's roll, check, roll, check. Manual roll bending 1.5" .095 wall tubes is a pretty good work out, too!
This pic reminded me how fortunate I am to have a high ceiling in the shop.

[tygaboy]

Looks good to me!

[tygaboy]

I'm not so confident that I trust my measurements on what to me are the trickier bits. This firewall arch is one of them. I knew the bar would intersect the long in such a way that it was going to require an interesting cut. So I prefer to sneak up these sorts of things using the "measure, cut, trial fit, measure, cut, trial fit" method until I get it where it needs to be, hopefully avoiding the "I cut it three times and it's still too short...!" situation. (IMG:style_emoticons/default/WTF.gif)

Here's the current state of things. The arch is dead on and overall fitment is looking really good.

The lower bar is a simple straight cut. I used one of those laser measuring devices and it was absolutely on the money. I cut the bar to that length and it's nice and snug.
And yes, I will be adding "footings" under all these bars so there will be more trimming.

I'm really happy with how this is turning out! (IMG:style_emoticons/default/piratenanner.gif)

[tygaboy]

In the pics above, the rear floor is just held in place with a floor jack to help locate the lower bar.
Now, it's on to making up some bracing for the lower firewall area, removing the tunnel and fabbing the rest of the floor supports. Not sure how much more I'll get done this weekend but I'm feeling pretty good about how this stage is going.

[Cracker]

Chris,

I like it. One word of caution; however, don't do anything that is permanent until you can fit the drivetrain in place. Too much structure, in place and done with will be difficult to re-do down the road (psychologically).

I'd suggest you take a break from anything relating to the lower fire wall at this point and focus on installing the entire driveline to achieve the most forward positioning of the transaxle as possible. To get the angles absolutely correct - the firewall will need to be modified. Now is the time to do that. Have I made myself clear enough???

I'm really only dealing with one issue at this point - CV angles. If you are patient, you can remove this from the table. All the best.

T

[tygaboy]

Suspension porn! Got my trailing arms back from Chris at Tangerine Racing:
stiffened, gussets, 911 e-brake assembly, hub-centric Carerra hubs, Elephant bushings, etc.
(IMG:style_emoticons/default/wub.gif)

[Cracker]

Damn right those are slick...Foley does excellent work! My struts head up to TR tomorrow to raise the spindles (plug for Chris - he CAN raise the spindle hieght on the tappered BOGE struts). Thanks Chris for the hi-jack!

Tony

[914forme]

Oh wow our builds are very close, I like what your doing keep it up!