Wow, it's been over a month since my last post. Quick update. I rolled the build table over to set the front subframe in place and see how it fit. I knew I would have to trim the upper mounts a bit and reweld a piece of 1/8" flatbar over the cut off pieces. What I didn't expect though, was that the front of the chassis itself was way the f...well, way off. As in not even close. I went back over everything, and none of the tacks were broken or out of shape. Turns out, the measuring implements I was using were from a time, many years ago, when a certain fella I worked with was, shall we say "hard" on tools. The squares were not, the level was not, etc. Needless to say, they went in the scrap bin. Bought some new good quality stuff. Yep, chassis is way off. Trapezoidal, out of square, etc. Everything except the passenger area. Somehow, that ended up perfect.
Really disheartening to say the least. My own fault for not double checking my tools.
, and one more
for good measure. So, it was time for Me, Myself, and I to have a "Come to Jesus" meeting. Throw in the towel, or suck it up, basically start over, and keep going. I was in a funk for a week. Decided that I really did want to do this, so out came the cutoff wheel on the 4" grinder, and off came the front of the chassis. Tubing won't go to waste, I'll use it for the triangulation pieces. Bought another length of tubing for the new front tubes, measured, cut, tacked, double and triple checked as I went along, and now we have a new front on the chassis. Also made the top an additional 1/4"higher to make sure the top of the chassis cleared the 'Vette sub frame. Plumb, square, etc. Got my rear hangar points figured out for the rear batwing, my co-conspirator will help me set that tomorrow. In the meantime, I picked up a HF tubing roller to make the curves for the dash and firewall hoops. Rolled a gentle curve from 1" .083 tubing, longer than I need by about 4" per side. Cut two 18" pcs. of the same tubing and used the Woodward tubing bender to make the two vertical pcs. of the dash hoop by leaving 6" before the bend, and proceeded to make a bend of 84 deg., on a 3" Center. Set them on the floor just to get a visual of about how it would look and transition, I think It is perfect. 1/2 hour to cut, roll, and bend the pieces. I'll cut to size and tack them up tomorrow as well. If that all works out tomorrow, I plan on taking a couple of "Mental Health" days, maybe Wed. and Thurs. to tie in the front end, and then start doing some of the final welding on the chassis.
I also have a question for those out there that have dealt with this kind of stuff before. I'm planning on running my ride height a bit higher than most, at 7" (About what a C4 Vette is). with the suspension set pretty much as it was in the C4, with only a couple of inches longer on the wheelbase, I'm thinking of the following:
1) 7" allows me to run the exhaust under and out the back of the car.
2) I can drop the engine and trans down to about 2" under the frame, and with 3" of suspension compression, still have 2" of clearance.
Doing a bit of research, I also found the following:
1) I can pick up 4" on the engine height if I dry sump the SBC. That would leave the bellhousing and flywheel as the limiting factor, and it just happens to be the same height as the stock Vette oil pan.
2) Quarter Master makes a 7.5" Clutch, Bellhousing, and Flywheel for the '86 and up SBC. I was considering going with a lighter flywheel anyway, so if I dry sump, I can pick up whatever the difference in the bellhousing size is for dropping the engine as much as another 3" or so. That would allow me to basically drop the engine 3" or 4 " and still have the oil pan just at the bottom of the chassis.
The only thing sticking in the back of my mind though, is if I get the engine center line down that low, how will it make the handling change. I think the stock C4's had a front vertical roll center of around 3.5 or 4 inches. In my current layout, the engine is already about 2" lower than the original mounts in the subframe.
As always, thoughts, comments, and criticisms welcome!