Come on guys. This man has something really cool going.. Keep up the good work..BTW.. I'll take the whole thing.... Going to be a very cool car...
so now I have a technical/safety/construction question. I want to get my engine mounts in the chassis this weekend, and I've settled on a design for the bellhousing mounts, but I've come up with a front mount idea that I need to bounce off you guys.... The front mount on the flathead six is two bolts on a plate above the timing cover. The stock mount has a rubber biscuit and then a horseshoe shaped thing that the legs bolt to the frame. I had initially considered just building a zoomie version of the stock horseshoe, that spread out to bolt to the top of the rails, but..... since I'm going to sit in front of the engine, and there will be a roll bar in front of the engine, and a firewall between me and the engine, could I put the roll bar in, then a horizontal cross brace, with a mount pad facing to the rear to bolt the upper front engine mount to? I'd feel better if there was an extra bar between me and the engine, and in theory the roll bar, with vertical bars, a horizontal cross brace, and two triangulating down bars to the front, would be the most structurally sound area to mount the engine, BUT.... is that just a no-no to mount the engine to the roll bar like that? I'm thinking in terms of hitting the wall head on at 100mph that's the best way to keep the engine from eating my lunch.
I would want the roll cage to be independent of the motor mount. What with the motor behind you, you could become like the bug on the windshield(splat). Oh those sudden stops.
precisely the scenario I'm trying to work around right now. I figure a head on at speed will have plenty of "splat" factor all on its own, so how do I keep the engine from contributing more than necessary? as food for thought, here's a middie (Miscalculation 1) now, put the forward bars at the top, triangulate down and forward. Put a horizontal bar across the roll bar hoop from side to side just above the timing cover. Put a plate between cross bar and engine. (Is that a better visual than the above description?)
The cross bar as an engine stopper is a cold hearted necessity. So as long as it's there anyway, might as well use it for something. On ours I welded the firewall in place as a permanent part of the rear hoop, mid frame cross member and horizontal stop bar (also upper belt mount), as basically a bulkhead. It's yet another security measure. Relative inertia at an impact would actually be far less of a spread with the engine attached to the cage than if it had even a few inches to go while you were "stopping". I kept our gap to just under two inches for that very reason. Our cage is different but on impact will function much the same as if you were to add a second, middle (perhaps lighter, but not much), "triangulation" starting at the cross tube and going forward to the same frame junction as the upper one on each side of the sample picture you have. Think of stacked triangles. This'd direct an impact load to a forward joint that'd pull the rest of the cage (and occupant) along rather than entering that driver's space. Personally though, If I didn't trust my engine mounts I'd cable tie the engine securely to the aft part of the frame and let the frame itself help fight any telescoping.
Hi Sled, our car being conventional in as much as the engine is forward of the driver, we used the top portion of the stock mount structure and made legs from streamline aircraft tube that extend to the chassis. The rear mounts are off of the bell housing and take all of the fore and aft loads and the front just holds the engine up in place. Like your build.......nicely out of the box.
I really dig your front mount, and while I don't have any aircraft tubing, was considering something similar until I came up with the cage mount idea. Part of my problem stems from not using the stock bell, which as you said, does the fore/aft motion duty. I'm kinda switching places in that way. you think it's out of the box now? wait two or three weeks....... btw- my registration for Mokan goes out Monday morning.
In #40 you give a better picture of your intentions. My thoughts are that if your going to attach the front mount to the cage, put a curved section of tube accross the back of the cage, so if the motor comes forward a little the load (if the tube bends) will not be into your back. In other words, a little room for safety. Your right, it will make a longer structure to spred the load. Go for it, but don't make the chassis too stiff. Wheel hop?
got the basic "dogsled" (thanks for the term CrkInsp) tacked up this weekend finally after some false starts the last couple weekends. Next on it is to go back and double check all the measurements, level, square, etc, before removing the scrap metal gussets to stuff the engine and trans back in the rails. Then finish the engine/trans mounts. also got the brake handle done, the battery switch mount done, and got started on the tail light, while I was fumbling on the chassis. one other thing- I was going to lock the carrier on the banjo w/ "Merc" axles, but have now decided otherwise, and have sent the spiders off with a knowledgeable friend to be machined pictures forthcoming.
Hey, Sled, Hot-damn ! You're mailin' in the registration for the MOKAN-MANIA ? Right on, Dood. I know I ain't been much help with the road-trip to Seattle area but mayhaps I can give you a hand this next week-end. Copco
If you're gonna run that outfit at MoKan, I have one question for ya. Did you ever get your carbs worked out? Best I recall your step-ups were a problem at the dyno. I may be behind, if so - catch me up. Hud
Hud- I'm not confident that the carbs are sorted properly. I argued repeatedly with my engine builder about tuning the carbs in the manner and order you and I talked about, but he wouldn't hear of it. It was his contention that fiddling anything but the end result at full throttle was a waste of time. So.. track tuning it is. I recently gained access to a knowlegeable and meticulous chassis dyno operator, so perhaps that will be in the cards for later. As it is, the engine has proven reliable with 30 pulls on the dyno, and, with its lack of proper airflow it limits itself pretty well, so, getting the thing on the track is the most important thing right now. I have a whole slate of engine changes for the winter teardown. Making time on the chassis has been KILLING me lately. Every time I turn around I seem to lose build time. All have are Friday evenings, Sat's and Sun's, and if I miss one, it hurts BIGTIME. This weekend I hope to get the engine and trans mounts done, the rear mounts done, and the bottom of the main hoop done. With that, I should be able to move on smoothly.
I spend alot of time reading folk's posts here. How they take off, run down the track, the fact they are actually shifting gears, etc. This much I think I can say with some degree of confidence, you need your carbs tuned correctly through each circuit. If you were starting off the line with a stutter box, maybe not. Feathering it in and out with the foot peddle - oh yeah. Box 'em up and ship them to me. I'm not doing anything but carb mods these days. I'm going to have to go into the Custom's carbs to change the float needles anyway - so it would be a good time to replicate those mods on your carbs as we are running nearly identical engine setups. I might even get fancy and set you up with replaceable air bleeds. While you're ironing out the chassis, it would be a good time to put those B&B's to rest. That way you'd be ready to take some final dyno pulls before the final install ahead of MoKan. We'll just call it my contribution to the mopar contingent. If I can't get one built, at least I can help you along just a tad. Hud
picture from Copco from Friday night He came and helped me measure everything out and set up for getting the engine and trans mounts in Saturday
Hey, Sled, You're cookin' now, Dood ! Lookin' good. That front engine mount looks perfect; can't wait to see it in person. Sorry I couldn't get over on Saturday, lotsa honey-do's. And the kids stopped over Sunday but looks like you made a bunch of progress. I'll stop by the shop; maybe I can snag another "customer."
pics of the recent progress- front cossmember, "seat bar" and rear roll bar braces all made and installed.
From basic layout and equipment selection to build quality, I really like your car a lot. Kinda wish I had stuck to more vintage parts for mine... Don't slow down on your build. I (along with many others, no doubt) want to see it in action, soon!
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