Project HEMI 55

[chevynut]

I got the stock brake pedal brace cut down and flanges welded onto it. I made a bracket that's going to be welded to the back of the firewall to mount it to.

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As you can see I cut the hole for the steering column. Steve bought a billet Flaming River column mount but the column is 2" and the mount is 1 3/4"! So we're going to use an Ididit one like mine that's a little smaller and fits better. Plus I can use mine to set it all up instead of waiting for his to arrive.

Next I have to build the support structure for the column and then the firewall can come back out for welding.

I still don't know what we're going to do about the brake pedal, or whether we'll even use the stock one. It's not something I agreed to address, but I have some ideas and may end up designing and building it for him.

[567chevys]

Looks good ,

Tons of work .
Hope he likes it .

Sid

[chevynut]

I've been working on the steering column mount and I knew it was going to be a challenge because of where it came through the firewall, and the engine clearance. I made a cardboard mockup to get close, then I went ahead and bent up a sheetmetal mount that will be welded to the firewall. This mount should address the brake pedal travel issue, since it allow at least 1" more room for the brake pedal to move toward the firewall.

Here's the final piece with the cutout for the Ididit column mount. It took a lot of trimming and fitting to get it to fit right....

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Once I got it to fit I dropped the engine and tranny in place and checked the fit (for the second time)...

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It's tight at the valve cover, but I have about 3/4" to the mount, and around 1/2" to the IDIDIT piece at the closest place. I installed the steering shaft and u-joints and confirmed that I have around 3/16" or more clearance to the headers and a-arm shafts.

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Here's a view from the inside before cutting out the brake pedal relief in the firewall. I'll do that after I tack the mount in place. I also installed an instrument cluster I had to make sure it all fit. I pushed the 32" column as far forward as possible to get the best steering shaft angle to the rack, and to clear the instrument bezel. The bottom of the column is 1/8" to 1/4" outboard of the stock location to help with header clearances.

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Next I have to remove the firewall and weld the whole thing up, then install it and weld it into the body. I think Steve's wanting me to set up his brakes too, and I have some ideas for that. Going to probably use a Hydroboost and move it 6" or so outboard of the stock location.

[Belair-o]

Chevynut,
Wow, very creative and innovative design and fabrication job. You are making fast progress on the puzzle of making it all work!
Regards, Doug

[WagonCrazy]

My gawd that's close to those headers and valve cover! Can you even get to the header bolts to tighten/remove them? Good work Laszlo...

[chevynut]

Paul, the header bolts are no problem. I always think about having to work on stuff when I design something.

I got the firewall welded together but haven't welded it to the body yet. I don't want to paint myself into a corner so I want to do all the fab work I can before the firewall gets welded in

Next problem.....if you look at the firewall you'll see there's no place to put a master cylinder in front of the brake pedal. I gave Steve the option of going through the floor and trying to get some sort of booster on the frame, which I wouldn't commit to working on, or moving the booster and master cylinder toward the driver's side. We tentatively decided to use a hydroboost on the firewall.

Then I did some measuring and I bolted on the hood hinge.

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The sharpie lines show the area I have to work with. Unfortunately, a hydroboost won't fit in that area due to the accumulator. With the accumulator in the 2 oclock position the hood hinge interferes, and with it in the 7 o'clock position the valve cover can't be removed.

So I gave Steve a couple of options to address that......a manual brake master cylinder, or an ABS electric booster. He decided to go with the electric booster. I'm not sure how well manual brakes would work on this application. This is what we're using....



The horizontal line shows the approximate vertical location of the master cylinder centerline. For the electric booster I plan to decrease the pedal ratio from 6:1 to 4:1 which I think will work better. So the booster will be about 1" lower than that line. Once it gets here I'll finalize the location and cut the hole.

I've also been working on the pedal assembly. I decided to make the pedal turn a 1" rod in order to move the booster over around 6". So I removed the stock pivot and machined a rod to fit snugly into the brake pedal. The right end will have a bearing boss welded to the pedal bracket, with a 3/4" ID sintered bushing in it. The pedal will be solidly joined to the shaft with a bolt through the pedal and shaft.

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At the other end I'll make a bracket that bolts to a 1/8" thick plate on the firewall (which will be welded to it) and the bracket will have another sintered bushing in it. The actuating lever will be welded to the rod once everything is fabbed up.

[WagonCrazy]

What if you talked your customer into using a 1 piece forward tilt front end? Then you could ditch the hood hinges altogether and pick up the room needed for the hydroboost?

Ditch the inner fenders too and you could do fenderwell headers on that Hemi!

[chevynut]

What if you talked your customer into using a 1 piece forward tilt front end? Then you could ditch the hood hinges altogether and pick up the room needed for the hydroboost?

Ditch the inner fenders too and you could do fenderwell headers on that Hemi!

If I had my hood hinges "productized" that's what we would be using. But that's a project for some other day....maybe. I don't know if aftermarket billet hinges would help or not. But there's another issue.....if I go over too far and down with the booster/MC, the tire could hit the master cylinder on full compression. A HB/MC is about 14" long. I designed mine a little differently keeping the height the same, and even with the shorter 10" booster and MC it's close to the tire. Imagine if this was 4" longer and 1" lower:

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I tried talking Steve into a set of custom headers so I could move the engine forward a little more, but he said no. I 's sure fenderwell headers would have to be custom too, and they probably would have caused even more problems.

[chevynut]

Steve got the ABS Power Brake booster ordered and it should be here Wednesday. I the meantime I worked some more on the brake pedal assembly.

I finished off the end of the shaft and and drilled a retainer bolt hole, and welded the bushing boss to the brace assembly. Then I drilled the pedal and shaft to lock them together. I fabbed a lever 3" long on centers with two additional holes for adjustments if Steve wants to tweak the braking. The 3" hole gives a 4:1 pedal ratio.


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Once the booster arrives I'll finalize the location and cut the holes in the firewall for it. I also have a plate I made that will be welded in to support that area. The last piece will be a bracket with another bushing on the left end that will be bolted to that plate.

[chevynut]

Got the booster the other day and located it and cut and drilled the holes to fasten it to the firewall. The hood hinge does interfere with it so I talked to Steve about it and he'll use some after-market hinges if he has to. The hinge doesn't seem to sit perfectly vertical in the stock holes so maybe the hinge is tweaked. I told him he may be able to make the stock hinges work but I'm not sure. In any case, I'm not worrying about it .

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After getting it mounted I found out that the pushrod is just about the perfect length....so that will save me some work not having to re-do it.


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