using the engine as a suspension member

racervette69 said:
mrvette said:
racervette69 said:
Dont think my frame would twist much, due the construction of the cage. Always heard solid transmission mount would crack the bellhousing or tail shaft. So far no cracks.
My Duck 900SS uses the engine to tie the frame together. I kinda like that.

corvette.jpg
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:hissyfit::bump::bounce::rofl::rofl::rofl::smash:

Sorry, but that pix in THIS thread, talking about cracking blocks when used for chassis/frame support...and that HUGE OIL SLICK next to the car.....

:3rd::3rd::banned:
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LOL,, the old Panhead was parked there earlier. :rofl: oil pump had crapped out causing the engine to sump..pushed it out the primary vent...:confused:
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UHH huhh....you can bullshit some of the folks most of the time but not ALL the folks ALL the time.....

just gotta rub it in.....:bump::bump::hissyfit::censored:
 
I think the real issue with potential cracking is when a mostly stock car is using the engine/transmission as a major stressed component. In cars with full cages, the stress introduced to the engine and transmission is significantly reduced. I firmly believe our stock frames are plenty "bendy" enough to crack a block. Speaking of which, I have a crack in my windshield to prove how bendy a frame can be.
 
clutchdust said:
I think the real issue with potential cracking is when a mostly stock car is using the engine/transmission as a major stressed component. In cars with full cages, the stress introduced to the engine and transmission is significantly reduced. I firmly believe our stock frames are plenty "bendy" enough to crack a block. Speaking of which, I have a crack in my windshield to prove how bendy a frame can be.
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who do you know that cracked their engine? what were they running?
 
Don't know the person/people personally. Just my conversations with my engineer friend and engine builder, both of whom have built cars for track use. I know it's second hand information but I trust the sources. If you don't, that's cool.
As for my personal experience, I firmly believe that the stock frame is way too flexible, especially in lateral and torsional loads. I believe this because after one particular track day I found a crack in my windshield that went from one A-pillar to the other, in the second layer of glass. The glass was not cracked prior to the track day and it is obviously a stress crack.
This was the initial spark for my conversation about loading the engine. As I often do, I went to my engineer friend and asked his thoughts on stressing the block to stiffen the frame, explaining my recent experience. That's when he explained the scenario I described earlier.
Keep in mind my caveat. Stressing a block in a tube frame or tube frame modified car will likely have little effect on the block. But it will also likely deliver minimal benefits in structural rigidity. Stressing the block in a mostly stock configuration will deliver more significant benefits, but with greater risk. I am only trying to pass on information that I trust so that those who try this reduce the risk and maximize the gain.
Your choice.
 
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In racecars, the engine is specifically designed to resist loads as part of the chassis with mounting points, stiffeners and etc. A typical engine case is not. Anything else is simply trial-and-error.

Think about the fact that even to bore a cylinder you want to use a torque plate to account for the minor deformations induced by the heads. Now place the dynamic wheel forces on the cylinder wall at the engine mount plus engine stresses and you are likely beyond the where you want to be.

George
 
Corvettes White said:
In racecars, the engine is specifically designed to resist loads as part of the chassis with mounting points, stiffeners and etc. A typical engine case is not. Anything else is simply trial-and-error.

Think about the fact that even to bore a cylinder you want to use a torque plate to account for the minor deformations induced by the heads. Now place the dynamic wheel forces on the cylinder wall at the engine mount plus engine stresses and you are likely beyond the where you want to be.

George
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I'm going to disagree with you unless you can be more specific about where these frame loads are coming from and how large they are. Drag racers put huge loads on these mounts when they dump the clutch or release the transbrake. I don't see bending/twisting moments from roadcourse loads being greater than that.

Now let's discuss head clamping loads. Each bolt provides up to 7000 pounds clamping load x 16 = 112000. That's really not comparible with frame twisting type loads. Apples and oranges.
 
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I have always used solid mounts, never a problem. Doesn't vibrate much more than poly either

On my 82 I have additional braces running from the bellhousiong to the frame rails in hopes of making the chassis more torsional stiff w/ them. They are angled down so they're not in a flat plane w/ the frame rails
 
Twin_Turbo said:
I have always used solid mounts, never a problem. Doesn't vibrate much more than poly either

On my 82 I have additional braces running from the bellhousiong to the frame rails in hopes of making the chassis more torsional stiff w/ them. They are angled down so they're not in a flat plane w/ the frame rails
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TT, is that before or after you mounted the birdcage on your car to reinforce the frame ?

You have a picture of that ?
 
Twin_Turbo said:
I have always used solid mounts, never a problem. Doesn't vibrate much more than poly either

On my 82 I have additional braces running from the bellhousiong to the frame rails in hopes of making the chassis more torsional stiff w/ them. They are angled down so they're not in a flat plane w/ the frame rails
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I too would be interested to see what you came up with. After the cracked windshield event, I did something that sounds remarkably similar to mine. I had pictures, but they died with my last PC :( For the record, mine is basically an upside down "batwing" bolted to the scattershield. And I used the scattershield specifically because I knew I was going to load it as a structural member of the car. Even though it's only loaded in one plane, I go under it after track events and check everything. Seems I can get 6-8 track days before I have broken/lost a couple bolts on the member. So, yeah, it's stressed.
 
I lost both my PCs due to water damage, the hard disc took a head crash on one and the other is completely fubar. I managed to recover some but lost a whole lot, especially pics. I can't find it anymore.

Basically it's a set of rods w/a mounting plate that bolts on the 2 side bolts of the bellhousing/engine, they angle down to a bracket on a frame. There's a poly bushing on the end between the frame and support bracket. IT's simply a set of rear motor mounts, sort of like a midplate idea.
 
Twin_Turbo said:
I lost both my PCs due to water damage, the hard disc took a head crash on one and the other is completely fubar. I managed to recover some but lost a whole lot, especially pics. I can't find it anymore.

Basically it's a set of rods w/a mounting plate that bolts on the 2 side bolts of the bellhousing/engine, they angle down to a bracket on a frame. There's a poly bushing on the end between the frame and support bracket. IT's simply a set of rear motor mounts, sort of like a midplate idea.
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Sounds like the roof came down on you because of the snow.
 
Belgian1979vette said:
Twin_Turbo said:
I lost both my PCs due to water damage, the hard disc took a head crash on one and the other is completely fubar. I managed to recover some but lost a whole lot, especially pics. I can't find it anymore.

Basically it's a set of rods w/a mounting plate that bolts on the 2 side bolts of the bellhousing/engine, they angle down to a bracket on a frame. There's a poly bushing on the end between the frame and support bracket. IT's simply a set of rear motor mounts, sort of like a midplate idea.
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Sounds like the roof came down on you because of the snow.
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Netherlands and New Orleans have a lot in common, can you imagine a hurry cain coming to the English Channel?? much less heavy SNOW to N/Orleans....???


:crap::surrender:
 
This is off thread, but we got the worst snow in decades, anyway i surely haven't seen anything like this in the 40 years i'm old. Nobody really was prepared. Had to clean the waterdrains of my roof because on every meter of drain there was about 40 kg of ice hanging in there. A part of that came down right in front of our door...
 
Belgian1979vette said:
This is off thread, but we got the worst snow in decades, anyway i surely haven't seen anything like this in the 40 years i'm old. Nobody really was prepared. Had to clean the waterdrains of my roof because on every meter of drain there was about 40 kg of ice hanging in there. A part of that came down right in front of our door...
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I know snow like that from my daze in Maryland, outside DC,...that weather can be a BITCH in winter....seen blizzards come though back when....I slid down a hillside and turned over to look up through a tunnel of snow about 10' above me......not easy to get back up....

my last winter there, was 4' in the driveway....

that spring I sold and moved to FLORIDA....

:clap::clap::clap::clap::clap::clap::clap::clap::clap::clap::devil::clap::clap::clap::clap::clap:
 
Damn weather,, hate it for you guys,,, winter is no longer a season, but an Fkn occupation.
 
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