Ron Tyler Differential Mount

[jmortensen]

You guys may want to consider that the crossmember holds the front control arms at a fixed distance and acts kind of like a strut tower bar does in the front. IF (and I don't KNOW) taking that piece out allows the front control arm mounts to move relative to each other, you'll be getting some funky camber and toe changes as it moves.

[Zs-ondabrain]

I agree, but at the same time, the car won't be hot-rodded around. I've spent way to much money and time on the 260Z to go thrashing around in it like Tom Cruise in a rent-a-car in "Days of Thunder"

I cut the center out in hopes of raising the dual exhaust up a few inches or so. Plus it looks different and kinda cool. If I find that it may be an issue, I'll make, or have one made, a bracket to act like a strut bar for the rear. But I won't be speeding, braking and cornering like a race car. I'm building it for Show, Cruising and Touring (long drives) It'll have all the luxuries of a sedan and the Sportiness of a coupe. Or at least that's what I'm shooting for. I'll have a better idea about the crossmember/diff/Rt mount and Camber when it's all in and drivable.

But thatnks for your Concern Jon, I know you're just looking out for me (Us)

Dave

[jmortensen]

I cut the center out in hopes of raising the dual exhaust up a few inches or so. Plus it looks different and kinda cool. If I find that it may be an issue, I'll make, or have one made, a bracket to act like a strut bar for the rear. But I won't be speeding, braking and cornering like a race car. I'm building it for Show, Cruising and Touring (long drives) It'll have all the luxuries of a sedan and the Sportiness of a coupe. Or at least that's what I'm shooting for. I'll have a better idea about the crossmember/diff/Rt mount and Camber when it's all in and drivable.

But thatnks for your Concern Jon, I know you're just looking out for me (Us)

Dave

Sure thing. I have done some funky mods to my car in this area and eventually (2015 or 2020 when I actually drive mine again) part of the plan is to actually test the difference with the crossmember and without in autox type driving. I agree that for a pure street cruiser it probably makes no difference as you said.

I was thinking of taking it off because it would make diff swaps SUPER easy, and add room for the exhaust as you said.

[EVILC]

You guys may want to consider that the crossmember holds the front control arms at a fixed distance and acts kind of like a strut tower bar does in the front. IF (and I don't KNOW) taking that piece out allows the front control arm mounts to move relative to each other, you'll be getting some funky camber and toe changes as it moves.

I also wondered if that was true. I on my old LS1 car, removed the crossmember and replaced it with two upright end caps. It made more clearance for my exhaust. I now have the crossmember in on the new setup just to ease my mind that it "should" be acting as a brace between the two control arms. Any idea on how to check that? Would imagine you can't just because real loads need to be there to check movement.

[EVILC]

Jon the main reason I wasn't running the crossmember the first time because it made getting the q45 diff in and out 1, 2, 3! The car was tracked a few times and couldn't find any damage or reasons to think removing the crossmemeber had any negative effect.

[jmortensen]

I also wondered if that was true. I on my old LS1 car, removed the crossmember and replaced it with two upright end caps. It made more clearance for my exhaust. I now have the crossmember in on the new setup just to ease my mind that it "should" be acting as a brace between the two control arms. Any idea on how to check that? Would imagine you can't just because real loads need to be there to check movement.

Just an idea, but you could use a ratcheting tie down and pull the front of the wheels together with the car on jack stands and then use a plumb bob on some part of the suspension to measure deflection, then do it again with the full crossmember in place. You'd need to have an extra crossmember cut up to check it both ways. I was going to test with my butt-o-meter.

[RT Hunter]

I have a question. Would the RT mount be as bad as a solid mount?

People say the solid mount will tear up the differential and mustache bar.

From what I see, the RT bar is kind of like a solid mount that it's keeping the differential against the cross member. But if it does allow movement, (since it has a rubber piece on top), would it come banging back down on the cross member = bad?

[Zs-ondabrain]

The R/T mount is nothing like a solid mount. Period. A solid mount is just that, Solid. The R/T mount is a hanging support for the diff, as apposed to a resting mount crossmember.

When the wheels get forward (1st gear thru 4th or 5th) power from the diff, the diff moves in an upward motion. If you have a regular crossmember and diff mount, the diff will try and pull away from the crossmember, and eventually, under heavy loads or Horse Power, will rip it apart.

Under the same conditions but with an R/T mount, the diff will merely push upwards towards the new urethane mount, in a "squishing action. So think of it this way..... If you put a trucks bumper up against a brick wall with a peice of Urethane inbetween and slowly accelerate, the truck won't go very far but the urethane will absorb the push.

But if you put a hole in the wall and tie the bumper to the brick wall and put it in reverse, somethings gonna give, whether it be the rope, the bumper or the wall. Click the link and you'll see what the Safety interlock is and how it's better than the stock mount.

http://www.energysuspensionparts.com/Installation_Instructions/Energy_Suspension/17112.pdf

The diff won't hit the cross member under deceleration because it's held Above the crossmember and the Urethane bushing required for the R/T mount is a "Fail-Safe style. So even if you remove ALL the Urethane from the mount, the mount will NOT fail because the 2 sides are interconnected.

[RT Hunter]

Thanks for the explanation.

I think I got confused because I saw a photo without the stock mount below the differential. The photo had the differential laying directly on the cross member. But I read another place, and found out you're actually suppose to have the stock mounts also.

I think I will get the RT mounts real soon!

[Zs-ondabrain]

The idea of the R/T is to eliminate the stock mount and it's possible failings under acceleration. If you find that the crossmember sits too close to the diff after the R/T instal, and the bolt heads may touch the X-member, drill out and area for each bolt head so that you still have the Xmember and the bolt heads clear and don't touch it.

You can kinda see the crossmember has been drilled out in the picture below. Just enough to clear the bolt heads.

[RT Hunter]

Oh ok, I see how it's suppose to look like now after the install. Thanks for the photo!

How much room is there between the differential and the crossmember? Looks like it's less than 1/4".

So under acceleration, the differential goes up. But how about when you decelerate while still in gear? Would it try to slam down onto the cross member?

[RT Hunter]

I think I just understood how the RT mount works now....

At first, I thought the RT mount was only pushing the diff. down.

But the mount is actually bolted to the differential itself, which also holds it from the differential going downwards even more - hence the reason not needing the lower stock mount?