Custom motor mounts?

[MikeG]

No it doesn't. Basic physics. Where did you get the idea that raising the crank centerline, would change the weight distribution??????

 

[snoranger]

Raising the crank centerline does move the weight around and helps driveline geometry and launch angles. Btw 87 mustang gt mounts were used in this hypothetical situation.

Good, you used 87 mustang mounts. Supposedly the 93 convertible mounts and aftermarket poly mounts (that are commonly used) sit the engine about 3/4” lower than the regular GT mounts... now you just need to find another 1/4”.

 

[Chris86ranger]

Raising the crank centerline does move the weight around and helps driveline geometry and launch angles. Btw 87 mustang gt mounts were used in this hypothetical situation

No it doesn't. Basic physics. Where did you get the idea that raising the crank centerline, would change the weight distribution??????

By raising the center of gravity of the vehicle in question, quite a few articles out there to read. Just Google raising crank centerline.

 

[MikeG]

I don't need to google drag-racing voo-doo. It's basic Euclidean geometry. If you can't put prove it with that, it's in the same category as sacrificing a chicken before the race, for luck.

If you want the ultimate crank centerline raise, then flip the engine upside down like the old Jumo inverted-Y engine that German ME-109s used. Easy Peasy!

Moving the engine back an inch does a little, but not very much. Example.... if you have a 100 inch wheelbase (just making that up to make the math easier) then 1 inch back puts about 1% more of the engine weight on the rear wheels. Your biggest concern is going to be getting it to fit at all, let alone fiddling with the position for some theoretical advantage. Either that or put it in the bed, and be done with it......

 

[JOLENE_THE_RANGER]

youll accomplish more by building weight transfer (squat) into your rear suspension geometry than you will moving the engine backwards one inch

 

[ericbphoto]

Since I can't spell Euclidean, I Googled the other thing. And, although it doesn't give an in-depth explanation of the how's and whys, this article does support the OP's desire to raise the crankshaft height a bit.

Y'all play nice.

A Little Setback: Engine Mounting Strategies for Drag Racing - OnAllCylinders

Just how important is engine mounting in a drag car? Very. Consider the case of a common rear-wheel drive production line car: Typically, mounts are laid out in a three-point …

www.onallcylinders.com

 

[MikeG]

He claims it will have an effect, but doesn't explain why. So.... I'm thinking it's more in the realm of voodoo.

In an extreme example, if the engine was as high off the ground as it was from the rear wheels (ie. driveshaft at 45 degrees to horizontal), the rear suspension squatting will physically move it a noticeable amount toward the rear wheels, and by moving it, yes there would be more weight on the rear wheels (as long as the nose of the car stays in the air). But if moving the engine back only picks up 1% more traction, then moving it up would only be a tiny, tiny fraction of that. Real? Perhaps. Measurable in the real world? I doubt it.

It should be easy enough to write out an equation, for anyone who passed high school physics. Till I see that, I'm calling BS. Or, more likely, the people claiming this, don't point out what a tiny, tiny, tiny fraction of anything this does.

 

[MikeG]

Just doing some musings, with a triangle calculator......

If the center of mass (CM) of the engine/transmission is 100" from the rear wheels (just to make the math easier, I know it's closer than that), and the suspension goes up 5" in the front and down 5" in the back, then the suspension "squat" effectively moves the CM back toward the rear wheels about an inch. The entire vehicle rotates about 5.7 degrees. That's because the CM moves in an arc, not because it gets physically closer to the rear wheels. The wheelbase is effectively an inch shorter, because of the rotation. That's a teeny bit more weight on the rear wheels, half a percent.

Making a ridiculous engine mount with the same 100" between the engine/transmission CM and rear axle, but with the driveshaft angle at 45 degrees, then the CM of the engine/transmission is now only 70.7 inches, horizontally, from the rear axle (but we have to raise the CM of the engine/transmission 70.7 inches to do that). What happens when the suspension 'squats'? The car rotates the same 5.7 degrees or so, but the CM of the engine/transmission is now just 63.3 inches from the rear wheels. So there's about 10% more weight transfer, of the engine/transmission, because the engine started out 6 feet up in the air.

But that's just the weight transfer from the engine / transmission, not the entire vehicle. So yeah we got 10% more weight (of the engine/transmission) on the rear wheels..... but we have to put the engine 6 feet higher!

So going up or down an inch isn't going to mean 'squat', no pun intended, in the real world. People can fool themselves that it's meaningful.

 

[snoranger]

The OP didn’t ask why... he asked how.

 

[MikeG]

True. Drill holes where you want them.....

My understanding that racers wouldn't use stock engine mounts if they could avoid it, they'd want the engine bolted to the frame (it was in the article you referenced). So if he's gonna fab them, then just make whatever fits. The existing engine mounts might serve as a template, if they could not be modified sufficiently.

 

[Broosedamoose]

I understand what your saying. When Windsor engines are put in an 87 Ranger (assuming from your signature) they will all sit in relatively the same place. If you want to go up and back 1" from that place you will have to make the mounts as no one sells them that way. You could uses the Mustang mounts and drill out the frame for the 1" back and then make spacers for the 1" up.

 

[Chris86ranger]

So two pages and twenty plus responses to answer a simple a question. No one produces an off the shelf or custom motor mount that would move the engine back and up. That's a whole lot of effort for a simple yes or no.

 

[ericbphoto]

Oh no. We could have put even more effort into this. Sorry if we cheated you out of the full experience.

 

[Chris86ranger]

One for all and all for none.

 

[MikeG]

That's why they're called "custom" .....