A new thread on the rearend in my lakester.....

[GPster]

Thanks for the reply.I really like to look at full scale explanations because it keeps me abreast of all the things that need to be looked at. GPster

[1FATGMC]

sirstude

several Zcars. I will check with them next time I get out there.

Thanks Doug and I'll keep looking also.  I think a second set of gears is still my best bet.

Sean

wedge pieces of keystock into the spiders, then Braze over them

Thanks Sean.  I think my 2nd line of attack if I can't come up with another set of spiders to modify is to try the bolts through the carrier into the spiders like I think you suggested earlier.  I looked at the carrier this morning and it looks like I could get 3 bolts into each spider this way.  My concern is that the spiders aren't very large in their diameter so the bolts would be pretty close to the center of them and that would reduce the leverage they had to resist the torque of the tires trying to turn the spiders through the axles and side gears.  The spiders and side gears don't turn very fast, but there is a lot of torque on them and that is why you can break an axle on the street with a locked rear.  That torque has to be stopped somewhere and in this case it would be a shear force on 6 bolts.  I talked to hooley this morning and he said the tires didn't chirp much on the salt and since the tires are so narrow he said it isn't like on the street, so the tire could slip much easier on the salt than it can on the street.

enjenjo

I'm having a brain storm.

I've been wondering when that would happen   .

enjenjo

If the spline is the same on the pinion shaft........

I'll see if I can get the yoke off and check this as a possibility.  Thanks.

Beck

This puts more side load on the gears making them bind a bit.

Tom it was good talking to you last night.  If I use Sean's bolt idea the bolts would also force the spiders into the side gears and maybe that binding along with the bolts into the spiders would be strong enough to not wory about breaking something due to the torque on everything from the tires in a turn.

   

Bruce Dorsi

What retains the stub axles in the differential side gears? .....Are C-clips used?

No C-clips.  If you look at the output shafts in the picture you can see grooves that circle the shaft where the splines are for the side gears.  Inside the side gears there are identical grooves.  There is one of those wire type clips that goes into the grooves and holds the shafts in position.  Since this rear has floater type outer hubs where the wheels are with pressed in axles and the 1/2 shafts are splined and can slide in and out on themselves there really isn't much in the way of side loads on these short shafts.

GPster

I really like to look at full scale explanations because it keeps me abreast of all the things that need to be looked at.

So does that mean I understood what you were saying   .

Thanks everyone for the input on this subject.

c ya, Sum

Finally Lakester Construction Has
Begun

[unklian]

Right now your around 150 HP,even with the turbo,your only going to have,lets say 400 HP,and your probably running on the long course.

I would think traction,and acceleration,won't be nearly as much of a problem,as on a faster,more powerful car.

A locked diff would help traction at low speeds,but an open diff might be safer at speed.

What is the consensus on the Land Speed board ?

[1FATGMC]

Right now your around 150 HP,even with the turbo,your only going to have,lets say 400 HP,and your probably running on the long course.

I would think traction,and acceleration,won't be nearly as much of a problem,as on a faster,more powerful car.

A locked diff would help traction at low speeds,but an open diff might be safer at speed.

What is the consensus on the Land Speed board ?

About 125 hp now and I hope for around 275-300 a couple years from now.  

Consensus?  Like asking what is better a Ford or Chevy or MoPar :? .  The guys over there will argue both ways.  For my car I don't think it will matter at all.  Like I said I'm mainly trying to look for ways to get around the lub on the side gear shafts and the base of the spider gears.  

The speed & Chrome site has a good video HERE  here:

http://www.speednchrome.com/gallery.video.01/video13.html

Check it out.  That is with a locked rear and 435 cu of Early Olds on fuel, that puts out over 700lb. ft of torque at 3500 rpm.

Thanks, Sum

[Sean]

Thanks Sean.  I think my 2nd line of attack if I can't come up with another set of spiders to modify is to try the bolts through the carrier into the spiders like I think you suggested earlier.

Weren't me. That sounds like a workable idea though.

[unklian]

I'm mainly trying to look for ways to get around the lub on the side gear shafts and the base of the spider gears.

I think all you need to do is grind a small spiral groove on the ID of the spiders to hold a little extra synthetic grease.Put it together,and forget it.

See what happens when you run it. :?:

If Salt is getting in there,you can machine a step in the ID,
to hold an O-ring.

Simple is Good.
Also makes getting replacement parts easier.

[Fat Cat]

OK I have done a little looking. There appears to be 2 different rearends used in the 240Z's But you most likely have the most comon one(I hope)   The most common one was used in the 240Z from 1970-73, the 260Z in 1974, the 280Z from 1975-78 the 1979 280ZX Coupe, and the 1980-83 280ZX R-180. It also was used in the 1977-79 Datsun 810 and the 1983-84 Nissan Maxima R-180.

The Hollander numbers for the differential case are manual trans #51774 and auto trans #52594. The side gears are manual trans #51776 and auto trans #53095

If you want any more info let me know.

[1FATGMC]

OK I have done a little looking. There appears to be 2 different rearends used in the 240Z's But you most likely have the most comon one(I hope)   The most common one was used in the 240Z from 1970-73, the 260Z in 1974, the 280Z from 1975-78 the 1979 280ZX Coupe, and the 1980-83 280ZX R-180. It also was used in the 1977-79 Datsun 810 and the 1983-84 Nissan Maxima R-180.

The Hollander numbers for the differential case are manual trans #51774 and auto trans #52594. The side gears are manual trans #51776 and auto trans #53095

If you want any more info let me know.

That is probably the one as the guy I got the rear from said it was also used in the 260 and 280Z.

Do they show a number for the spider gears?  I have e-mails to a couple places who say they have 240, 260, 280 parts, but haven't heard back yet from any of them.

Thanks for your help,

Sum

[sirstude]

Sum

Went out to the yard on Saturday, and they have 6 or 7 Zcars with rear ends.  They were not willing to part out any of the rears, all complete and in the $250 range for each.  I was hoping for one hit in the back that they would part out.

Doug

[GPster]

If I am following this discussion correct this is going to be a 200 MPH hopeful on the long track with one brake. If any of these locking ideas breaks  and one axel is free in the carrier then you will have only one wheel that is braked. If the idea you have chosen really scatters than the only thing the brake will do is slow down the engine if the chain is still good. One (more) simple idea. Take the axel gears out of the carrier and machine them for keys and make the matching key slots in their respective bores in the carrier. Allow the back of the axel gear face to remain entact so that there is a surface to keep the keys in place( the inside edge of the carrier bearing will hold the keys from coming out the other side). These keys won't be full length. Use the  shaft for the spider gears and a machined block to hold the axel gears apart and in their place. The axel gears will be keyed to the carrier so there won't be any motion there requiring lubrication. There will be no spider gears and no worry about coming up with spares or lubrication. The only pieces requiring lubrication will be the bearings which can be sealed and the chain. The chain lubrication is going to be thrown straight out not side-ways to the brake disc and calipers. The keys should keep the axels locked and brakable and for tuning and checking the driveline I would think you could pull the spider gear shaft and blocking and slide the axel gears inward enough to remove the keys. Now I can think about getting splash pans big enough to keep oil off my new driveway. GPster

[unklian]

How bulky is the DeDion tube going to be ? :?:


The axles look pretty big already.
Anything hanging out in the breeze will slow you down.


What if you had some Ford Banjo style axle tubes bolted to a swing arm ?
With an chain drive diff in between.

That way you only have one tube in the breeze,instead of two.
Maybe add some streamlining to the tube to make it more of a tear drop shape.

And do the rules specify the number of studs on each wheel ? :?:

[1FATGMC]

Sum

Went out to the yard on Saturday, and they have 6 or 7 Zcars with rear ends.  They were not willing to part out any of the rears, all complete and in the $250 range for each.  I was hoping for one hit in the back that they would part out.

Doug

Doug I think I have some spider gears coming.  I got an e-mail last night from a guy on a "Z" board that says he has some I can have.  He is in SE Asia right now, but will be back this week   .  Thanks for looking.

If I am following this discussion correct this is going to be a 200 MPH hopeful on the long track with one brake. If any of these locking ideas breaks and one axel is free in the carrier then you will have only one wheel that is braked.

Joe it looks like I'm going to be using a set of welded spiders, which lots of people have done, so I think I'll be ok.  BTW there are some 300 mph cars there running with just one brake.  Even after Hooley's 200+ mph run he said he just coasted off to a stop.  That is the nice thing about b'ville--lots of room to stop.  Thanks for worrying about me   .

How bulky is the DeDion tube going to be ?  
The axles look pretty big already.
Anything hanging out in the breeze will slow you down.

If I use the deDion tube it will be proabably 2 1/2 inches in dia. or square.  It would be located right behind the 1/2 shafts so it wouldn't add any to the height of that area of the car.

I had thoughts of a-arm type swing arms on both sides of the car going to the outer hubs, but then gave up on the idea.  After seeing the pictures of the following sand car I'm reinvestigating that idea.

   

Now this is a long suspension travel car.  If I do this my 1/2 shafts will be parallel to the ground and I won't use a coil-over hanging out in the wind.  It is too complicated to explain how I'll handle the suspension, but it will control the travel of the outer hub.  I'll try and get some sketchs posted when I get time.  BTW some of these sand cars are running turbo 'busa motors in them.  LINK TO SAND CARS  

And do the rules specify the number of studs on each wheel ?

Only "vehicles with tires having a dia. of 29" or greater, or with wheels over 17" in dia."  My tires and wheels won't be in that catagory.

   

I finished mounting the sprocket to the carrier over the weekend (CHECK HERE).  Next I'll make the adapter for the disc brake rotor and that will finish up the center section (thanks for getting the aluminum Benny).  At this point I'm committed to trying the center section out as it is.

Thanks for everyone's help on this,

Sum

[unklian]

Ideally,the A-arms need to be made of Streamlined tubing,
or wrapped in sheetmetal to crate a similar shape.

While a round tube will have less drag than square,it will still have much more drag than a streamlined tube.Conversely,a streamlined tube can be larger,and have the same amount of drag,or less than a round.

If you planned it out,you could make the axles run inside an enclosed A-arm assembly.The streamlined shape of the assembly could be airodynamicly cleaner than a collection of round tubes.

A transverse leaf could handle spring duty,or rocker arms with inboard springs and shocks.

Solid axles would be smaller in diameter than the tubular axles you have,allowing for a smaller cross section profile.

Double check the rules on streamlining,
as they apply to suspension.

[1FATGMC]

Ideally,the A-arms need to be made of Streamlined tubing,
or wrapped in sheetmetal to crate a similar shape.

While a round tube will have less drag than square,it will still have much more drag than a streamlined tube.Conversely,a streamlined tube can be larger,and have the same amount of drag,or less than a round.

If you planned it out,you could make the axles run inside an enclosed A-arm assembly.The streamlined shape of the assembly could be airodynamicly cleaner than a collection of round tubes.

A transverse leaf could handle spring duty,or rocker arms with inboard springs and shocks.

Solid axles would be smaller in diameter than the tubular axles you have,allowing for a smaller cross section profile.

Double check the rules on streamlining,
as they apply to suspension.

   

Ian none of the parts you are talking about will be out in the air.  There will be a streamline fairing going out from the body, like a wing that will house all of these parts.  That is why I'm trying to get them all in the same level plane.  The fairing will start at the front of the car and go to the back, covering both the front and rear axles, control arms, and suspension pieces.  I talk more about it on THE FIRST PAGE  of my construction site.

Please let me know if any of that doesn't make sense.  One of the nice things about b'ville is everyone has different ideas on what will work and some times you find cars that take a very different approach that both set  records.

c ya, Sum

[unklian]

Making more sense as time goes on.
I see a Solar Powered Racer influemce.

I wonder if such a long streamlined side pod would create too much drag due to surface friction ?

Perhaps smaller sections over the front and rear axles,similar to a Soap Box Derbt Car,would produce less drag,and could be adjusted independently.

OR your design could be used to generate some downforce at speed.
Vertical side panels would capture the air underneth,
and the curve of the underside of the side pod would create downforce.

There are 2 main enemys at Bonneville.Drag and Lift.
The question is how to reduce and balance them.

Wasn't the body on Flatfire designed with a bunch of wind tunnel time ?
There are lots of side views around,but not many from the front.
I'm guessing it's real pointy,and makes the air go down the sides,instead of over top which would create lift.