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nicksoccer22

Diff Swap Affecting Brakes?

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I'm not sure if this belongs in the drive-train or brakes section, but with black Friday coming up I thought I'd throw it here since It gets more views, MODS feel free to move it.

I'm new to IRS suspension and I'm really having trouble wrapping my head around how a diff swap will affect the car. I've read the FAQ's and I think a q45 diff is the way I want to go. As I said I'm having trouble visualizing how this all goes together, is there a picture or some kind of diagram with all the components like the half shafts and companion flange? and all that other stuff and how it all connects? my biggest question is will it affect my brakes? I want to get set from silverminemotors if they have a black Friday sale, but I'm worried that a diff swap would change the hub, or something to make the brakes no longer fit. I'm sorry that this is a probably a pretty silly question, but there's a lot of new terms I don't know, and its hard for me to understand it in word form. I get the difference between the short and long nose diffs and how they are mounted, but everything beyond that confuses me.

1. Is there a diagram or laid out and labeled image of how the q45 or similar diff connects to the 240z stuff?

2. Would a q45 swap affect my aftermarket brake choices?

Thanks Guys!

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Totally depends on how you're planning on connecting the short nose R200 (Q45 diff) to the S30 chassis.

If you're going to get the full Techno Toy Tuning package, then yes, your brakes and pretty much everything on the rear end will be changed.

However, if you're planning on doing something else...

I guess you could get some kind of custom mount to mount the R200 to the chassis, then get some sort of custom adapter to bolt your axles to the diff output flanges. That way you'd still be using the same axles and hubs.

I'm not sure anyone sells those parts though.

Also, if you're not sure what is part is what, power goes from the engine to the tires in this order

Engine>>>Transmission>>>Driveshaft>>>Diff input flange>>>Diff gears>>>Diff Output Flange>>>Axles>>>Companion Flange>>>Stub Axle>>>Tires.

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Sorta off topic, but I just want to clarify something on the first post in this sticky, 

Jmortensen gives a list of things to do to put a long nose r200 into a 72-73 240z 

1. mustache bar from 280Z with R200

2. yoke (companion flange) from 280Z with R200

3. rear cover from 280Z or ZX with R200

4. side stub shafts from 280Z or ZX with R200 to bolt up to stock halfshafts

Of these components Diff Output Flange>>>Axles>>>Companion Flange>>>Stub Axle>>>Tires, the only parts you'd need from a 280z with a long nose r200 would be the companion flange and stub shafts/axles? And because the stub axles are being changed, brake upgrades for a 240 would no longer fit, and I'd need 280z stuff, assuming I sourced the stub axles from a 280z? 

 

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Ok well lets get back on topic.

A Q45 doesn't have a Longnose R200. It has a short nose R200, and is completely different.

casedifferencefull.png

Are you going to install a Longnose R200 (which are commonly found in the 280z) or a shortnose R200 (which are commonly found in the Q45)?

Or are you talking about getting the Longnose R200 out of a Z31, which uses CV axles and has an LSD equipped?

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I should have been more specific when I said I was getting off topic. I was just trying to see if I was understanding that post on the sticky correctly when asking about the 280z with a long nose r200. 

 

I'm still interested in the q45's short nose, but it seems like there is a lot more involved in it, and with my limited knowledge on this, I might need to reconsider. 

 

To my previous post, if I did swap the 280z long nose and it's companion flange and stub axle, would I then be in the market for 280z brakes? I just want to make sure I'm understanding the basics of this before I get too deep down the rabbit hole.

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If you're just putting on a 280z longnose R200, then you don't actually need the companion flange and stub axle.

However, as it is stronger than the 240z stub axle, if you're planning on boosting power at all, it wouldn't be a terrible upgrade to do.

As far as rear brakes go, if you're upgrading rear brakes to disk brakes, then it doesn't matter if you change the stub axle and companion flange. They don't affect the rear rotor or mounting surface.

Here is an example that shows that the 240z,260z,&280z all use the same rear brake upgrade.

http://www.silverminemotors.com/datsun/datsun-280z/brake-upgrades/stage-4-rear-big-brake-kit

I would recommend reading a lot more, multiple times, most of the stick threads, as well as just looking at the rear end of your car to see what all the parts are actually doing. There is a wealth of information on this site. Just keep searching.

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The brakes are completely separate from the differential.  You could install a Ford, Chevy, Mopar, Suzuki, Yamaha, Kia, etc. differential and not have to touch the brakes at all.  At all, no bleeding, adjusting or anything, not even the parking brake.

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Thanks for the info NewZed, I had figured that's how it worked, but I didn't want to drop 600 bucks on a set of brakes that I would eventually have to swap out. And thank you NeverDone, I'm a 4 hour drive from my car and any of my manuals. so the description of how the power got delivered was helpful, I'll be sure to reread the sticky's a few more times.  

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On ‎11‎/‎20‎/‎2017 at 12:10 PM, nicksoccer22 said:

I'm not sure if this belongs in the drive-train or brakes section, but with black Friday coming up I thought I'd throw it here since It gets more views, MODS feel free to move it.

I'm new to IRS suspension and I'm really having trouble wrapping my head around how a diff swap will affect the car. I've read the FAQ's and I think a q45 diff is the way I want to go. As I said I'm having trouble visualizing how this all goes together, is there a picture or some kind of diagram with all the components like the half shafts and companion flange? and all that other stuff and how it all connects? my biggest question is will it affect my brakes? I want to get set from silverminemotors if they have a black Friday sale, but I'm worried that a diff swap would change the hub, or something to make the brakes no longer fit. I'm sorry that this is a probably a pretty silly question, but there's a lot of new terms I don't know, and its hard for me to understand it in word form. I get the difference between the short and long nose diffs and how they are mounted, but everything beyond that confuses me.

1. Is there a diagram or laid out and labeled image of how the q45 or similar diff connects to the 240z stuff?

2. Would a q45 swap affect my aftermarket brake choices?

Thanks Guys!

Hey I was wondering what car you are working on. I have a R200 with a Mfactory LSD and everything needed to put into a 240, that I am not using. It is nearly new and in excellent condition. If you have interest let me know. 

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