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I would only buy mounts that are covered by a Life Time warranty. Corksport doesn't fall into that category.
I've been going back and forth between the JBR and corksport units. The JBR unit actually seems to have a smaller bushing diameter so even at the same 70 stiffness rating the JBR unit will be stiffer.

When I look at the corksport unit it looks a little close to the subframe on the top under load, it's tough to tell from the pictures/video. I wouldn't want to be contacting things if I'm running 20-30% more torque than stock...but at least the corksport unit is symmetric creating a nice straight load path between the bushings that makes the mount unlikely to break.

The JBR unit however is flat on the bottom and really kinked on top which is not good from a potential cracking standpoint. You have the basic tension load from being pulled apart, plus a bending moment that also adds tension at the upper radius, plus a stress concentration as a result of the tight curve. It's a recipe for a fatigue failure at some point, and aluminum has much poorer fatigue properties than steel.

So I would take my chances with the corksport unit warranties or not. Hopefully clearances are more than adequate even with a modified engine. Maybe corksport can provide some actual clearance data static and dynamic.
 

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People are always much quicker to complain than to compliment.
I've been going back and forth between the JBR and corksport units. The JBR unit actually seems to have a smaller bushing diameter so even at the same 70 stiffness rating the JBR unit will be stiffer.

When I look at the corksport unit it looks a little close to the subframe on the top under load, it's tough to tell from the pictures/video. I wouldn't want to be contacting things if I'm running 20-30% more torque than stock...but at least the corksport unit is symmetric creating a nice straight load path between the bushings that makes the mount unlikely to break.

The JBR unit however is flat on the bottom and really kinked on top which is not good from a potential cracking standpoint. You have the basic tension load from being pulled apart, plus a bending moment that also adds tension at the upper radius, plus a stress concentration as a result of the tight curve. It's a recipe for a fatigue failure at some point, and aluminum has much poorer fatigue properties than steel.

So I would take my chances with the corksport unit warranties or not. Hopefully clearances are more than adequate even with a modified engine. Maybe corksport can provide some actual clearance data static and dynamic.


OK, Good luck with that.
 

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I run the JBR 70dm mount, and there's a lot of NVH under 1500rpms, but helps a lot with wheel hop and traction
 

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I didn't think about it possibly helping traction and wheel hop.

I've attributed that more to the suspension bushings, specifically the trailing arm bushings that have a bunch of holes in them in the direction (down) when torque is applied to the wheels. I'll be filling them with urethane at the same time I swap the mount, so wheel hop should improve dramatically.

Fatty04, Presumably idle NHV is worse since it's the lowest rpm? Is it just vibration or is it harsh and noisy too? I came from a miata, so I'm not worried about this much I'm just curious of your opinion.
 

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Idle is tolerable, not bad at all, but you know the mounts there. But climbing off idle will buzz my review mirror. And rattle my sunglasses in the headliner compartment
 

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!!! that sounds pretty intense. I'd probably be better off with the corksport unit having a larger bushing diameter possibly being a bit softer...

Thanks for the feedback.
 

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Discussion Starter · #30 ·
I think the forums scared them in to submission. I've completely forgotten about this thread and how much hate there was for CS. I even read the other thread that demonized the company. I have a few of their products and never had any issues.. even the ones that had the most complaints. BUT people DO complain just to complain.

Bottom line is, it's a small company and they don't exactly have the resources to do extensive R&D. What R&D they have are performed on volunteer test cars. I don't blame the guys for having a few defects because in the light of things, it's just a few defects.

*shrug*
 

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Personally I do notice that it seems harder for me to engage 2nd gear on a full throttle shift (MTX). It seems like the gate moves to the left on me so I bang the shifter betwen 2nd and 4th and grind a bit, but it's a fixed shifter mount on a cable actuated assy so it shouldn't matter should it? The only thing I can think of is the rocking of the engine exceeds the excess length of the right-left cable, essentially tugging on the shifter fork and "moving the gate" relative to my shift lever position. If that is the case then this stiffer motor mount would help solve that problem.
So, did the mount make a difference with the shifting?
 
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