510 Goon IRS Swap - goin lower...

[]2eDeYe]

Sorry Jrock, they were capping everything underneath. I'll swing by again tomorrow.

 

Here is a shot of the lower mount with the suspension out of the car.

 

[datsunfreak]

Dumb question: From the looks of it, the stock spring pockets on the lower control arms line up with the frame rails. Why not use springs there instead of all the reinforcement necessary for coilovers? Just for more adjustability?

[]2eDeYe]

Dumb question: From the looks of it, the stock spring pockets on the lower control arms line up with the frame rails. Why not use springs there instead of all the reinforcement necessary for coilovers? Just for more adjustability?

 

Not a dumb question, it was contemplated.

 

There is not as much room there as there seems, so the control arm would have to have a deep pocket and the frame rail might have to be shaved into non existence.

Then you would still have to mount shocks, though they would not require as much reinforcement.

 

Basically the coilovers are a much tighter package and required less fabrication to mount. Plus no need to have a compressor, tank and valves.

[jrock4224]

awwww nice ... thats quite a lot of leverage that has been gusseted....i would still gone bag.....thats alot of shear stress right there supporting the car....simple answer why coilovers... one location handles shocks and coil....theres no room under a goon....looks nice .. no rush on pic of car on ground... just anxious...me personally if i was gonna make that mount that way ... i would have trussed the two mounts to more of the control arm... being there what holds the car up ... even though its gusseted everywhere i look at is the longer the mount the longer/or more surface area the attachment to the suspension arm should be.....all the length is in the cantilever against the arm.... there are compound stresses there that could create some issues...a simple way i look at it is, the length of the mount linearly should equal or exceded the mounting surface to the arm...tough on this set up, but if you triangulated the mount again u would half the stresses you are leveraging on the mount thats there.....using thicker steel is never the answer as your just adding to the unsprung weight leveraging against that arm/mount...i have seen 1/2 plate ripped off of frames in shearing fashion under normal loads..i also am of the opinion that the factory shock mount needs to be plated closed theres a lot o emphasis on that one side of the mount and although it is tubed for the og mount i would still plate those as one since that tube is not gonna do much if failure should incureand once its plated i would truss the back of the mount if nothing else, meaning u cant add a triangulation to said mount due to half shaft interference......... .i hope that kinda makes sense...i always try to over build as a suspension failure usually ends up in a wrecked car...or worse..

 

 

 

..great progress.....this so makes me wish i had a irs laying around

[LaidoutRivi63]

 

I have to say I agree with what was said Above. Not to be critical but using heavier metal just makes the chances of it failing at the original mount, it's around 10 gauge, way higher because of the heat from where it was welded. Also, those long triangle gussets transfer all the long moment into a small area where the welds are likely to break and separate. If I could offer a suggestion. Why not tie into it from the spring pocket under the half shaft. Curve it for shaft clearance, and box-truss the whole thing. Then the mount is more part of the arm than just a large moment arm. I'd stick to 1/8" plate too.

[jrock4224]

rivi is outlining the exactly what i was thinking in fixing the concerns..at least to disapate some of the load...the half shaft doesnt move up and down enough to inferfere with the triangulation.....1/8 is more than sufficent...again please dont take this as bashing i just am suggesting for the longevity of the swap and basic bulletproofness...none of my suggestions are anymore than that, suggestions and can be used or not....i still love where this car is going just sharing some of my experiences

[Farmer Joe]

didnt frank and jeff do it like this on that other white goon?

 

looks fine as it is..

[jrock4224]

let the your being a jerk lemme prove you wrong posts start......WHAT PART OF A SUGGESTION WAS MISSED I N YOUR READING OF MY COMMENT ... i even said in my post that it was just that....im not hating on this im suggesting ... hey if it works great .... but i could drive home on a square wheel and that would work too but its not the best way....i know if that mount breaks and that wheel is shoved up into the well its gonna get exciting fast....why not spend an hour assuring that doesnt happen...redeye tell them to keep up the good work and let them know i wasnt being a jerk simply sharing some thoughts on things i have seen and done and how to maybe improve on a obvioulsy proven way that farmer outlined...till then i will wait for pics and keep my suggestions to myself ...

 

 

farmer u know this car will be piloted by a female ...which is not a bad thing, but i wouldnt want to send my wife out in my goon that could suddenly have a rear one wheel lock up at freeway speeds.....when i coulda spent a hour making sure that wouldnt happen....mayybe you should look at the entire picture(back story..) before racing into to defend, well nothing...

[Farmer Joe]

whoa whoa buddy..

 

so are you there, and know what the mount looks like in every aspect? cmon guy...

 

guess we'll see later if there another pic snapped from a different angle.

[]2eDeYe]

awwww nice ... thats quite a lot of leverage that has been gusseted....i would still gone bag.....thats alot of shear stress right there supporting the car....simple answer why coilovers... one location handles shocks and coil....theres no room under a goon....looks nice .. no rush on pic of car on ground... just anxious...me personally if i was gonna make that mount that way ... i would have trussed the two mounts to more of the control arm... being there what holds the car up ... even though its gusseted everywhere i look at is the longer the mount the longer/or more surface area the attachment to the suspension arm should be.....all the length is in the cantilever against the arm.... there are compound stresses there that could create some issues...a simple way i look at it is, the length of the mount linearly should equal or exceded the mounting surface to the arm...tough on this set up, but if you triangulated the mount again u would half the stresses you are leveraging on the mount thats there.....using thicker steel is never the answer as your just adding to the unsprung weight leveraging against that arm/mount...i have seen 1/2 plate ripped off of frames in shearing fashion under normal loads..i also am of the opinion that the factory shock mount needs to be plated closed theres a lot o emphasis on that one side of the mount and although it is tubed for the og mount i would still plate those as one since that tube is not gonna do much if failure should incureand once its plated i would truss the back of the mount if nothing else, meaning u cant add a triangulation to said mount due to half shaft interference......... .i hope that kinda makes sense...i always try to over build as a suspension failure usually ends up in a wrecked car...or worse..

 

 

 

..great progress.....this so makes me wish i had a irs laying around

 

 

I have to say I agree with what was said Above. Not to be critical but using heavier metal just makes the chances of it failing at the original mount, it's around 10 gauge, way higher because of the heat from where it was welded. Also, those long triangle gussets transfer all the long moment into a small area where the welds are likely to break and separate. If I could offer a suggestion. Why not tie into it from the spring pocket under the half shaft. Curve it for shaft clearance, and box-truss the whole thing. Then the mount is more part of the arm than just a large moment arm. I'd stick to 1/8" plate too.

 

 

rivi is outlining the exactly what i was thinking in fixing the concerns..at least to disapate some of the load...the half shaft doesnt move up and down enough to inferfere with the triangulation.....1/8 is more than sufficent...again please dont take this as bashing i just am suggesting for the longevity of the swap and basic bulletproofness...none of my suggestions are anymore than that, suggestions and can be used or not....i still love where this car is going just sharing some of my experiences

didnt frank and jeff do it like this on that other white goon?

 

looks fine as it is..

 

 

Yes it is pretty close, they used a boxed section instead of the gusseted plate but it welded on in the same place. Not much room under the car back there.

 

 

 

 

I'll try to address the above concerns...let me know if I miss something.

 

The vertical plate, that takes most of the load of the car, is welded to the original shock mount stud that was trimmed off and left in the arm. Boxing that area really won't add much strength to the mount as the shock mount stud is captured by the two side plates, but I guess it couldn't hurt either.

 

The way this suspension works, there is not a ton of fore-aft load going into that mount as the lower control arms take that load through the bushings at the K member. The shocks are almost parallel to the upper crossmember, when looking at the car from the side, so they impart most, if not all, of their load down and out.

 

There is not much to tie to under the half shaft and welding to the bearing housing did not seem like a good plan. The forward gusset could go a little farther forward to the bearing housing, but again most of the load is vertical coming down through the shock.

 

My main concern with this design is the smaller section that allows clearance for the body of the shock, but there has to be clearance there. This to me is the weakest point, but I believe it will be ok as there is a decent section area there.

 

The only piece of 1/4" is the long leg that attaches to the both the old shock mount stud and the new lower shock mount. All the gussets are 1/8" plate and the lower mount is made from 1/8" wall tubing.

 

 

The car will be given a thorough shake down before going back to the owners.

 

Hopefully that addressed everything.

 

 

Thanks for the constructive criticism, it is helpful to get your guys input. :)

 

 

 

I'll try to get a couple pics from different angles for you guys tonight.

 

 

 

PS

Jrock, sometimes it's really hard to grasp your point with the way you ramble/post. :lol:

[jrock4224]

farmer....no m not there but have built a ton of suspension systems and seen alot fo things good and bad.....i was simply suggesting ....i dont need to see the other side...no one has to do what i say no ne has to agree with what i say.....it was simply a suggestion ...i know when i work on ohers car s and do fab work i always try and try to think of everything and any scenario that would go bad....im not basjhng the welds or the plate or the fab ... it all looks great i just blieve in over kill and double redundancy when it comes to suspension...i will refrain from posting anymore info and just keep it positive like i thought i was being ...

 

 

red eye.... thanks for taking the time to read my post and attempt to understand it ... sorry if there confusing ....i was just sharing some thoughts...thats it ... wasnt trying to insight a war...i can sympathize with your comment reguarding no room under there....i know from changing my link suspension design three time now that fitting anything under a goon with the intention of not invading cargo and sitting space is hard...everything in ths thread makes me want a irs goon....trailer made is doing it right...and i will just shut up and watch...i really wish i coulda made the wish bone idea work ...im changing my mazda to a three link.....and its such a painless design... meaning im a mini trucker... but no the kinda minitrucker that likes his gastank and air shit in the bed... i like to use my bed....

 

funny im tryin to sell my fullsize thats bagged.... and every email i get is the bed is stock and wheres the air shit...what can i say it took a long time to get everything the way i wanted and get it to lay out completely front to back with out cutting up the bed....the one ton in my avatar had all the air shit n the bed cause i was in a rush... never again...my goon is getting some cool hidden stuff for its air managment

[LaidoutRivi63]

If you post more pictures, I can do the statics and strengths calculations as close as possible using your pictures and my rear clip on the lift. Not as an attack, but for piece of mind for yourself. I can get a good idea what kind of forces each of those components is seeing with a little work on paper. I did not and still do not mean any offence as I am only making judgement from a single picture. however, somethings may not become apparent in a shakedown. My friends bagged car snapped a adjustable stud on a wishbone setup after 2 months of hard driving. It was a slow break that happened because it was only just strong enough. He was lucky enough that it happened at 40mph and not at 80.

[datsunfreak]

2eDeYe' timestamp='1349964291' post='773666']

Not a dumb question, it was contemplated.

 

There is not as much room there as there seems, so the control arm would have to have a deep pocket and the frame rail might have to be shaved into non existence.

Then you would still have to mount shocks, though they would not require as much reinforcement.

 

Cool. :thumbup:

 

I ended up putting my springs on the frame, but they are really short. Not too short, but short nonetheless. Static height the springs are about 7" long, pretty comparable to a standard 8" (free height) coil spring. Had to go fairly stiff though (240 wheel rate) to make sure none of the bits bang into each other. ^_^

 

For me it came down to wanting to use the stock shock mounting spots. It would have been "better" to go through the floor and attach coilovers to a cage, but the mantra has always been to not do anything that can't be undone. So that way I can put the stock rear end back any time. Don't ask me why. :P

[]2eDeYe]

.i know when i work on ohers car s and do fab work i always try and try to think of everything and any scenario that would go bad....im not basjhng the welds or the plate or the fab ... it all looks great i just blieve in over kill and double redundancy when it comes to suspension...i will refrain from posting anymore info and just keep it positive like i thought i was being ...

 

 

When in doubt, build it stout ;)

 

red eye.... thanks for taking the time to read my post and attempt to understand it ... sorry if there confusing ....i was just sharing some thoughts...thats it ... wasnt trying to insight a war...

 

 

 

We got thick skin around here :devil:

 

 

If you post more pictures, I can do the statics and strengths calculations as close as possible using your pictures and my rear clip on the lift. Not as an attack, but for piece of mind for yourself. I can get a good idea what kind of forces each of those components is seeing with a little work on paper. I did not and still do not mean any offence as I am only making judgement from a single picture. however, somethings may not become apparent in a shakedown.

 

 

 

No offense taken. :)

 

It's about a 6" lever arm with 200lbs static load when the car is sitting. The 1/4" plate is about 2 1/2" at it's narrowest. More pics below.

 

 

 

Cool.

 

I ended up putting my springs on the frame, but they are really short. Not too short, but short nonetheless. Static height the springs are about 7" long, pretty comparable to a standard 8" (free height) coil spring. Had to go fairly stiff though (240 wheel rate) to make sure none of the bits bang into each other.

 

For me it came down to wanting to use the stock shock mounting spots. It would have been "better" to go through the floor and attach coilovers to a cage, but the mantra has always been to not do anything that can't be undone. So that way I can put the stock rear end back any time. Don't ask me why.

 

 

Build thread? :D

 

 

 

 

Now for a few more pics.

 

Keep in mind that most of the welding was done in this position. :lol:

 

 

 

 

...and that this is a BUDGET build.

 

 

 

 

 

They boxed in the old shock mount as suggested. This ties the solid 3/4" stud to the top of the mount.

 

 

I can see some areas to that can be strengthened in this pic ^ I'll have to take another look tomorrow and see if it's just the angle of the shot

 

 

 

We really don't mind the criticism as we want the car to function and be safe. I have a load test planned, should be fun :rofl:

[datsunfreak]

2eDeYe' timestamp='1350005160' post='774052']

 

Build thread? :D

 

 

Oh, sorry. ^_^

 

Sadly, some of my photo links are busted because of the site I had my pics hosted on, but here's the thread:

http://community.rat...the-1200-today/

 

Pic of the spring before I built the upper spring mount, compressed with the weight of the car on it:

 

 

 

 

Pic after the rear was finished:

 

[]2eDeYe]

Nice! I didn't realize you finished that swap.

 

Was your ebrake still functional? I just realized that's why the shock support is the shape it is.

[datsunfreak]

2eDeYe' timestamp='1350008229' post='774088']

Nice! I didn't realize you finished that swap.

 

I'll still probably tweak a few things here and there, but it's "done" enough to drive just fine.

 

Was your ebrake still functional?

 

Oh goodness no. ^_^

 

But it could be, had I left the 510 brakes on it. I took them off and put on 280ZX disc brakes. I ditched the stock stuff in favor of one of these:

 

http://www.ebay.com/itm/Blk-Hydraulic-handbrake-e-brake-Kit-Evo-8-9-STi-Grip-Lever-Ebrake-Parking-Lever-/230858601825?pt=Motors_Car_Truck_Parts_Accessories&hash=item35c03eb561&vxp=mtr

 

Ratcheting hydraulic e-brake. Works as a parking brake, and as a cutting brake. ;)

 

I just realized that's why the shock support is the shape it is.

 

Yeah, trying to mimic the stock 1200 shock location and movement.

[VintageRice]

First time seeing this thread.

 

RAD

 

Keep going, hurry up and GETER DUUUUUUUUN SON!

 

 

:D

 

Love that goon.

[jrock4224]

2eDeYe' timestamp='1350005160' post='774052']

 

 

 

I can see some areas to that can be strengthened in this pic ^ I'll have to take another look tomorrow and see if it's just the angle of the shot

 

 

 

We really don't mind the criticism as we want the car to function and be safe. I have a load test planned, should be fun :rofl:

 

extending that lower gusset all the way to the outside edge of old shock mount is what i assume u mean..and a few others i see, but im not bringing that up again....looks good... i see a powder plug protecting some threads from slag b b's.....i can sympathize... i runined a weld on bung tacking some fourlink stuff together...

[Rustina 510]

Great work

[]2eDeYe]

extending that lower gusset all the way to the outside edge of old shock mount is what i assume u mean..and a few others i see, but im not bringing that up again....looks good... i see a powder plug protecting some threads from slag b b's.....i can sympathize... i runined a weld on bung tacking some fourlink stuff together...

 

Yep, I remembered that the e-brake cable occupies that spot but there might be room for a bit more structure there.

 

I'm confident it will hold up as is, just the main plate held the car up with no deflection dragging the car around the shop by a couple jacks.

[erikcarter]

looks amazing. I am watching this thread I am getting ready to do the same swap to my goon. Thanks for the blueprints!

[]2eDeYe]

Thanks.

 

There's a bit of pink down there :lol:

 

 

 

 

They had to weld those brackets in to hold the stock tank.

[jrock4224]

um ok wierd question... why is there a spark plug in the upper right hand corner of that pic of the diff and gas tank pic...

[datzenmike]

Plugging the fuel line. (ironic ain't it???)

 

 

Aw man, not a strut bar. I wanted to see them do this without going into the cargo area.

 

Would not the rear seat brace across the back when latched in place? Maybe it could be strengthened?