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Engine torque limiter
#11

(03-09-2021, 01:44 PM)Just Add Boost Wrote:  Only issue will be grinding off the powder coat in the weld area.
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You don't think the dampening biscuit will melt while welding, Chris?  OR.....are you gonna remove the biscuit(s) altogether? <shrug>

Since the L/H (driver's-side) mount is in "tension" during acceleration, the bolt is really the only thing that needs to be uber strong. Sooo......you could  temporarily use a wooden biscuit between the upper and lower mounting brkts in order to see if making the mount "solid" is gonna yield the results you're after. 

This whole scenario kinda boggles my alleged mind, cuz I wouldn't have thought that those types of mounts would deflect enough to allow much "rotational" engine movement. Usually, torque straps/struts are only needed with "spongy" stock mounts to prevent shearing the rubber dampening material. OTOH, I used an aluminum front and steel "mid" motor plate, along with a rubber trans mount on my S/Gas Vega.
Placerville, California
(former)  '78 2.3T Courier w/blow-thru Autolite 2bbl carb ~ (current)  '87 2.3T Ranger w/PiMP’d EFI
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#12

I don't think these mounts allow much movement but I also think the exhaust really can't tolerate any side to side movement without putting a heck of a load on the turbo/header.
I did notice when I was putting the engine in back in January that the driver side mount was loose where you could actually tilt the upper separate from the lower. I cranked down the center bolt at least one full turn and it tightened everything back down.
Maybe that was the issue and it is now solved..who knows?
Just don't want to break the header again..
88 TC: 2.9L tall deck, SVO head, boport header, sheet metal intake, BWS300SXE turbo, AWIC. C4 trans. E85
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#13

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I don't blame you for wanting to prevent future header cracking, Chris!  Maybe it's time to reconsider that flex joint you alluded to earlier &/or support that heavy turbo & WG with a homemade "spring strut"......as depicted below in my "pencil CAD" drawing (posted previously on TF), lol. BTW, the ends should be "articulated" via Heim ends, so the turbo can move around as the header tubes expand/contract with heat cycling. <shrug>

[Image: Dk71NMB.jpg?1]
Placerville, California
(former)  '78 2.3T Courier w/blow-thru Autolite 2bbl carb ~ (current)  '87 2.3T Ranger w/PiMP’d EFI
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#14

I have a 3.5" flex joint but it is too fat to fit anywhere along the exhaust. That's how tight everything is.
Bruce said the next time the engine is out we should build a custom midplate to replace the current plate and attach it to the frame. Maybe just leave these mounts in place and do that so I don't have to mess with a front motor plate.
88 TC: 2.9L tall deck, SVO head, boport header, sheet metal intake, BWS300SXE turbo, AWIC. C4 trans. E85
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#15

Those are some of my mounts and they're steel, and the bushings are 70A durometer poly.

If you wanted to do solid in place of the poly, you'd want to have a way to locate the bushing on the larger hole in the upper bracket. A bit of 2" to 2-1/2" dia AL with a 1/2" hole in it and a machined locator on one end could work. You wouldn't need the upper bushing either.

The torque limiter, mounted a bit higher would save from the additional NVH, however.

It sounds like your biggest issue is the lack of a flex joint on the exhaust. They're not solid, but my mounts restricted most engine movement.

The SVO's had dampers, not limiters. To make the SVO seem more "refined" they went back to the big rubber block mounts the earlier cars used, but those also caused the engine to flop all over. The dampers helped reduce some of that, without adding NVH.
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."
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#16

Update to this. I actually removed the urethane "biscuit" between the upper and lower mounts. I measured the total thickness and then cut a piece of 1-3/4" roll bar tubing to fit in place of the urethane. After putting the mounts back on for correct clocking, Bruce welded the tubing as much as he could access while mounted to the engine. I then pulled the mounts back off and he finish welded them. I then shot a couple coats of epoxy paint and reinstalled them.
Did some initial test drives this past weekend. It was not as bad as I was expecting. A little buzzing in the steering wheel and the windshield mirror is now pretty blurry (side mirrors are ok) but other than that not a big deal. With no hood I was used to seeing the engine vibrate a bit at red lights..no more of that, rock solid now.
Keep in mind this is a weekend toy that maybe gets 1000 miles a year put on it. If it was a true daily I may have gone a different route.
Ready for some track time this friday!

   
88 TC: 2.9L tall deck, SVO head, boport header, sheet metal intake, BWS300SXE turbo, AWIC. C4 trans. E85
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#17

Hmmm.........it's interesting that you "solidified" the passenger-side mount, Chris (the one that gets compressed during acceleration/launching). I woulda thought that the hard-durometer poly biscuit on Chuck's mount could only compress maybe 1/8-1/4 inch. I.e., most folks that use torque straps or chains, install 'em on the L/H (driver's) side to prevent/limit the mount on that side from being "pulled/stretched" apart or to its' limit. <shrug>
Placerville, California
(former)  '78 2.3T Courier w/blow-thru Autolite 2bbl carb ~ (current)  '87 2.3T Ranger w/PiMP’d EFI
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#18

I converted both mounts to solid.
88 TC: 2.9L tall deck, SVO head, boport header, sheet metal intake, BWS300SXE turbo, AWIC. C4 trans. E85
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#19

[Image: 371907850_BEER_TOAST_400x400.gif]
Placerville, California
(former)  '78 2.3T Courier w/blow-thru Autolite 2bbl carb ~ (current)  '87 2.3T Ranger w/PiMP’d EFI
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