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Wilhelm
Few pics of a project I'm working on to break up the misery or paint, bondo and rust removal on my V-8 SBC conversion. I'm going to do the sheridan body work on my car and found these wheels which I liked.

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The problem is the wheels are 10 inches wide with an offset of 2 inches. In searching the web site it seems that most people with this combo have gone with 3" spacers. This seemed like it would put a lot of force on the bearing and I still would not have many other rear brake options. So.... I found some rear 928 hubs on ebay. the bearings are much larger: 85mm diameter and 47mm wide (versus stock 75mm diameter x 37mm long) and this would provide me with other 5 lug rear brake options. So off to the barn.



First, put a piece of 5 inch 1.25 inch wall DOM(Drawn Over Mandrel steel tubing) in the lathe.



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Wilhelm
Cut off everything that didn't look like rear hub.........


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Cut the sides off for the 928 brake shoe backing plates.


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And was left with new hub that could hold a larger (928) bearing. Sure is purty at this point. I'm finally getting the hang of turning parts. The 2 critical dimensions in this hub are the diameter of the bearing bore and the length of the bearing bore back to the its front which is a large circlip. I was confident I got these within 1/1000. Everything else can be done in hundreths.


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Wilhelm
Found a some 11 gauge 4.75" outside diameter tubing, cut it to length and beveled one end.


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Then pressed it into place.

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Then practiced the TIG welding. Sure like that alot, no mess, no spatter but a steeper learning curve than mig. If you look closely, you'll see some bung welds about 5/8" down from the main weld. Just being a bit anal retentive. Doubt this was necessary as I put the press to the limit shoving the hub into the tubing.

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iamchappy
Impressive!....
Wilhelm
Cut the old hub out of a 914 swing arm and than welded in my new 928 hub assembly. Made a jig to keep the alignment all the same. The new exterior bearing surface is 3" farther out than the old 914 stock face.

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Had a 944 turbo brake disc that dropped right onto the 928 hub without any issues.

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Here is how the new wheel will sit on the widened hub without a spacer.

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Advantages:
Bigger bearing
Bearing is moved to center of wheel for less angular loading on bearing.
Should be able to handle the SBC V-8
Bigger brakes
Parking brakes
Takes my mind off my troubles and pesky body repair

Disadvantages:
More weight (will do a comparative weighing- will be using aluminum caliper)
Time

To do:
Finish the parking brake
Add brake caliper bracket
Add some reinforcement
Powdercoat the arm
Make an axle spacer
SirAndy
smilie_pokal.gif


how does the brake attach?
idea.gif Andy
Wilhelm
QUOTE(SirAndy @ Aug 10 2008, 11:30 PM) *

smilie_pokal.gif


how does the brake attach?
idea.gif Andy


More pics and explanation to follow. Basically it will be like the 914, but instead of "ears" for the caliper there will be a plate with a 4.75" hemicircle cut out of one end and 2 holes 3.5" apart on the other end. This will be welded perpendicular to the 4.75" tubing and the caliper will bolt to this.
sww914
What you've done looks great! Good ideas for sure.
My only concern now is all the extra torque that distance will put on the stock trailing arm. Do you plan to reinforce it somehow or deal with that problem if it arises?
Mikey914
Nice. Saw a set of turbo twisties on CL locally and had the same thought, but knew it was beyond what I was capable of. Kind of wild, having the same idea... nice to see someone execute it as nicely as you have.
neo914-6
Excellent work and great idea!
Wilhelm
QUOTE(sww914 @ Aug 10 2008, 11:52 PM) *

What you've done looks great! Good ideas for sure.
My only concern now is all the extra torque that distance will put on the stock trailing arm. Do you plan to reinforce it somehow or deal with that problem if it arises?


Doubt moving the bearing outward transmits any additional torque to the trailing arm compared to a stock arm with a 3" spacer and this same wheel or a stock arm with a deep offset wide wheel and no spacer. This design puts a lot less torque on the bearing compared to a spacer setup. Plus the bearing is substantially hurkier. Certainly comparing this trailing arm to a stock one with a stock wheel there will be additional torque applied to the arm. I have a set of stock sheet metal arm reinforcements shells I can weld on, but my hunch is they are better at adding weight than strength. I did a search on arm reinforcements where tubes were welded across the insides of the trailing arms. Unfortunately the pics of this thread are all gone. Guess it was a proprietary secret? Think most likely I will run a diagonal from the hub adjacent to the back of the parking brake plate forward at 45 degrees to the outside of the trailing arm keeping it inside of the wheel rim. Anyone have better ideas?
Wilhelm
Since I can add the brake bracket for my caliper essentially anywhere over 360 degrees, can anyone state a sound reason why I shouldn't point it straight up rather than tipped forward at about 100 degrees like the 914?
PeeGreen 914
QUOTE(Wilhelm @ Aug 11 2008, 01:03 AM) *

QUOTE(sww914 @ Aug 10 2008, 11:52 PM) *

What you've done looks great! Good ideas for sure.
My only concern now is all the extra torque that distance will put on the stock trailing arm. Do you plan to reinforce it somehow or deal with that problem if it arises?


Doubt moving the bearing outward transmits any additional torque to the trailing arm compared to a stock arm with a 3" spacer and this same wheel or a stock arm with a deep offset wide wheel and no spacer. This design puts a lot less torque on the bearing compared to a spacer setup. Plus the bearing is substantially hurkier. Certainly comparing this trailing arm to a stock one with a stock wheel there will be additional torque applied to the arm. I have a set of stock sheet metal arm reinforcements shells I can weld on, but my hunch is they are better at adding weight than strength. I did a search on arm reinforcements where tubes were welded across the insides of the trailing arms. Unfortunately the pics of this thread are all gone. Guess it was a proprietary secret? Think most likely I will run a diagonal from the hub adjacent to the back of the parking brake plate forward at 45 degrees to the outside of the trailing arm keeping it inside of the wheel rim. Anyone have better ideas?


Eric Shea does the tubes that strengthen the arms. I would think you would be well advised to do something like that as you are putting more stress on the arm. The bearing I am sure is fine but the arm is now the weak point. May be fine as it is though. Nice work aktion035.gif
Rick_Eberle
QUOTE(Wilhelm @ Aug 11 2008, 06:08 PM) *

Since I can add the brake bracket for my caliper essentially anywhere over 360 degrees, can anyone state a sound reason why I shouldn't point it straight up rather than tipped forward at about 100 degrees like the 914?


That is a nice job!

As to the brakes, won't having the caliper horizontal make bleeding difficult?
roadster fan
Nice work, wish I had some of those tools pray.gif

Here is a pic of the trailing arms with the reinforcements like you described, cant remember who did these (Shea confused24.gif ). Chris Foley was doing the reinforcement by cutting/sectioning the arm and welding in a plate....kinda hard to describe.

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Keep us posted on the progress,

Jim
Wilhelm
Thanks for the info on the reinforcements!

The trailing arm build continues. It was 108 F here Saturday, the shop was 120 F inside and wasn't able to do anything till today. Here is a drawing of the adaptor flange. From my measurements it will work with the caliper I choose with it's adapter or a 944 turbo caliper as a direct bolt on.

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Here is the flange cut out of some plate.

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Flange welded onto the new trailing arm.

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With the backer to support the parking brakes.

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And with the brake shoe carrier

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Wilhelm
Here are the parking brakes set in place without the cable and gizmos to make it work.

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928 hub put in for trial fit.

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944 turbo disc put onto 928 hub

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Detail of adapter for the new brake caliper as seen from the back.

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r_towle
awesome work...

I agree that what you did will add the same if not less stress to the trailing arm than the guys with 3 inch spacers...

Rich
Krieger
Nice work. Do you think the axles are going to hit the inside of the new trailing arm tubes you fabbed, or have you figured this out too?
John
Wow!

That is some excellent thinking.

Are you going to have some sort of bolt on bearing retainer or are you relying on the press fit of the bearing? I think the bearing will be big enough.

I would consider stiffening the trailing arm a bit (but not too much). You DON'T want to make the suspension console the weak point in the rear suspension. It would be a bitch if you ripped that off the car instead of bending an arm.

It looks good so far. Expensive machine work, but it sure looks good.

just my $0.02
SGB
Simply amazing. Wow that sweet. smile.gif
Wilhelm
As the axle would be going into a deeper hole, the angle it could traverse before it contacted the side wall of the tube would be limited. I am using 911 axles and making an aluminum spacer that fits between the connection of the CV joint and the stub axle. This will place this connection back to the normal orientation and regain normal range of motion.

The bearing is held in place on 928s by a huge freakin internal circlip.

It probably would be expensive machine work if I farmed it out, however doing it myself is fun. Certainly more fun than sandblasting sheetmetal and fixing rust!
Todd Enlund
Damn, dude... that rocks. aktion035.gif
Wilhelm
Forgot to add this should anyone else be interested in making one. Truly the only critical dimensions are the bearing bore 84.933mm and bearing depth, ie depth of bearing pocket to back of circlip.

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andys
Wilhelm,

Just catching up after 5 days in Puerto Vallarta, Mexico, thus the late post.

Nice work. Good to see someone thinking outside-the-box. I curious why you chose the 928 bearing? Most think the 914 bearing is more than adequate, and the 911 bearing beyond most needs.

I went with the 911 bearing mostly because it matched the late 911 axles, and I also moved the bearing further outboard in order to fit my 6 speed transaxle. Much like your work, here are a couple of photos of what I did (BTW, I can appreciate the amount of work that goes into this kind of thing). I fabricated a custom trailing arm.

Andys
Brett W
One thing to keep in mind, on a unit bearing like these, the distance between the centerline of the wheel and the bearing centerline determines the amount of torque the bearing sees. So you wouldn't necessarily have an overloaded bearing if the bearing centerline and the wheel centerline lined up.

Good job on the parts though. You need to use a little more filler rod and a little less heat on your TIG welds. Looks like you have a little undercutting.
ClayPerrine
QUOTE(andys @ Aug 20 2008, 05:13 PM) *

Wilhelm,

Just catching up after 5 days in Puerto Vallarta, Mexico, thus the late post.

Nice work. Good to see someone thinking outside-the-box. I curious why you chose the 928 bearing? Most think the 914 bearing is more than adequate, and the 911 bearing beyond most needs.

I went with the 911 bearing mostly because it matched the late 911 axles, and I also moved the bearing further outboard in order to fit my 6 speed transaxle. Much like your work, here are a couple of photos of what I did (BTW, I can appreciate the amount of work that goes into this kind of thing). I fabricated a custom trailing arm.

Andys


From experience...


Junk the Wilwood spot caliper. If you set the brake when the rotor is hot, after it cools it won't release. You will end up beating the shit out of the caliper trying to get the park brake off.


andys
Clay,

I've read that opinion before, but unfortunately only after I had already completed the work. Do you know why it doesn't release? Is it a symptom of the Wilwood design? Many cars use calipers and pads for parking brake applications, so I'm wondering what's the deal? Guess I'll find out for myself as soon as I get the wheels on the ground. I have all the 911 stuff just in case this doesn't work out.

Andys
Brett W
The Carrera GT used a spot type caliper.
IPB Image
McMark
Beautiful... drooley.gif
PeeGreen 914
Ummm... Can I have that rear suspension? biggrin.gif
Wilhelm
"I curious why you chose the 928 bearing? Most think the 914 bearing is more than adequate, and the 911 bearing beyond most needs."

I have a 928 and am familiar with this so had a reference for it during the design phase. Also I got complete rear hubs/carriers/brakes shoe setup for both rear corners of ebay for $25.00 a pop, much cheaper than I saw for any 911 stuff. Like many of you I am a CSOB.

"You need to use a little more filler rod and a little less heat on your TIG welds. Looks like you have a little undercutting."

Thanks, I appreciate any tips. I'm early on in my TIG welding having done MIG for 25 years. While welding this I think I was concentrating more on good penetration and was trying to avoid melting filler onto my weld rather than integrating it into my weld. I can see that it requires more eye hand coordination than MIG. I find myself pausing, taking a deep breathe, and getting set, before running each bead. Seems like with MIG I've gotten used to hitting the trigger and running with it!


ClayPerrine
QUOTE(andys @ Aug 21 2008, 12:11 AM) *

Clay,

I've read that opinion before, but unfortunately only after I had already completed the work. Do you know why it doesn't release? Is it a symptom of the Wilwood design? Many cars use calipers and pads for parking brake applications, so I'm wondering what's the deal? Guess I'll find out for myself as soon as I get the wheels on the ground. I have all the 911 stuff just in case this doesn't work out.

Andys



It is the Wilwood caliper design. for some reason it won't release after the brake cools if it is set when the rotor is hot.

Wilwood discontinued the spot caliper for that reason (that's what I was told when I phoned them about it).



But this is cool..

Hydraulic Caliper with Mechanical Park Brake

Maybe as a replacement for a stock 914 rear?
ClayPerrine
QUOTE(Brett W @ Aug 21 2008, 02:15 AM) *

The Carrera GT used a spot type caliper.
IPB Image



Custom built brembo caliper, not the Wilwood one. This is a known problem with the Wilwood spot caliper.

andys
QUOTE(Wilhelm @ Aug 21 2008, 11:34 AM) *

"I curious why you chose the 928 bearing? Most think the 914 bearing is more than adequate, and the 911 bearing beyond most needs."

I have a 928 and am familiar with this so had a reference for it during the design phase. Also I got complete rear hubs/carriers/brakes shoe setup for both rear corners of ebay for $25.00 a pop, much cheaper than I saw for any 911 stuff. Like many of you I am a CSOB.

"You need to use a little more filler rod and a little less heat on your TIG welds. Looks like you have a little undercutting."

Thanks, I appreciate any tips. I'm early on in my TIG welding having done MIG for 25 years. While welding this I think I was concentrating more on good penetration and was trying to avoid melting filler onto my weld rather than integrating it into my weld. I can see that it requires more eye hand coordination than MIG. I find myself pausing, taking a deep breathe, and getting set, before running each bead. Seems like with MIG I've gotten used to hitting the trigger and running with it!


$25 bux is way cheap; I see your motivation.

Going from MIG to TIG, just slow down a bit and get used to using the pedal to control your heat. As they say, practice, etc.

Andys
ClayPerrine
For what its worth, even Wilwood is using a parkbrake like a 911....


Wilwood rear brake kit.
Brett W
Glad I haven't bought the Wilwood spot caliper.
seanery
nice project! it's very cool!!!
andys
QUOTE(ClayPerrine @ Aug 21 2008, 11:55 AM) *

QUOTE(andys @ Aug 21 2008, 12:11 AM) *

Clay,

I've read that opinion before, but unfortunately only after I had already completed the work. Do you know why it doesn't release? Is it a symptom of the Wilwood design? Many cars use calipers and pads for parking brake applications, so I'm wondering what's the deal? Guess I'll find out for myself as soon as I get the wheels on the ground. I have all the 911 stuff just in case this doesn't work out.

Andys



It is the Wilwood caliper design. for some reason it won't release after the brake cools if it is set when the rotor is hot.

Wilwood discontinued the spot caliper for that reason (that's what I was told when I phoned them about it).



Clay/Brett/et al,

Today I phoned Wilwood with regard to Clays experience of the caliper sticking closed after applied to a hot rotor and subsequently cooled. I asked to speak to a tech guy with several years experience. The tech guy told me he is unaware that any problems exist in this regard. The only complaints they have center around the un-fixed pad rattling (the moveable pad simply sits loosely in a cavity and can rattle around; kind of a poor design, IMO). He said many of these spot calipers are used on kit cars without issue. BTW, they still offer the spot caliper anlong with replacement pads even though it is not listed on the current site (?). Nevertheless, I told him if I encounter a problem like Clay described, I will call in the complaint. He welcomed any feedback without apprehension.

So, I will try out the spot caliper as you see it in my photo. If it sticks as, Clay describes, I'll post it here and call Wilwood. In the meantime, I'll keep my Carrera parking brake hardware just in case.

Andys
charliew
I don't know why this additional challenge occured to me yesterday but I really appreciate you'all sharing your solutions as they are great.

I wonder if the wilwood caliper or the pads are already heated up and have expanded more than the rotor when the brake is set and therefore the pads are bound up from the rotor not shrinking as much as the caliper? If it does happen and you do get it loose you might try a cushion spacer of some type under the stationary pad to keep it from being bound up on cooling, maybe even a warped washer ( I don't remember their real name)

It could also be the flexing of the mounting bracket from the leverage applied to the arm. I am sure you can figgure it out and make them work.

I know it's a pain but if it does lock up you might try jacking up the car and loosening the wheel and rotor and it might save beating the caliper up.

Both solutions look great to me.

I am going to try to move the 914 bearing housing out ward andrefabing the arm or a copy of the arm out to it to try and not have the stub axle so far up in the bearing housing, this may prove to be easier said than done. I currently think the 914 bearings are large enough. I already have the 911 brake and stub stuff and it looks to be enough brake for a hot suby in this light car to me.

I think it's better to have more heat than filler than more filler than heat.
My previous experience with torch welding helped me on my curve with tig. I don't have any grip in my left hand so I have to stop and reposition the wire pretty often so that is my challenge. My best friend is a welder and fabber by trade so I have all the advice I will ever need. His beads are almost robot perfect.

I guess my search abilities are not real good as I missed this yesterday when I was starting this solution search.
Lou W
Very nice work. beerchug.gif
burton73
QUOTE(ClayPerrine @ Aug 20 2008, 08:06 PM) *

QUOTE(andys @ Aug 20 2008, 05:13 PM) *

Wilhelm,

Just catching up after 5 days in Puerto Vallarta, Mexico, thus the late post.

Nice work. Good to see someone thinking outside-the-box. I curious why you chose the 928 bearing? Most think the 914 bearing is more than adequate, and the 911 bearing beyond most needs.

I went with the 911 bearing mostly because it matched the late 911 axles, and I also moved the bearing further outboard in order to fit my 6 speed transaxle. Much like your work, here are a couple of photos of what I did (BTW, I can appreciate the amount of work that goes into this kind of thing). I fabricated a custom trailing arm.

Andys


From experience...


Junk the Wilwood spot caliper. If you set the brake when the rotor is hot, after it cools it won't release. You will end up beating the shit out of the caliper trying to get the park brake off.

Hi Clay,

I just ordered a set of Wilwood Mechanical spot calipers to make parking brakes for my V8 car that will have Boxster brakes with Rich Johnston adapters. Just to be sure I called Marty today at MSDS that runs them on his Turbo 914-6 car and they did a second car and he says they are perfect. I went over this with Eric Shea for a long time on the phone and he said as far as this thread went, it made no sense as the 914 brakes are really set up to be mechanical E calipers when we pull the handle.

Is this a red-hot racecar brake problem? Can it be the pads?

The only discontinued item on the web was a different number that the 120-2281,
120-2280.

Bob
ClayPerrine
QUOTE(burton73 @ Dec 8 2008, 11:28 PM) *

QUOTE(ClayPerrine @ Aug 20 2008, 08:06 PM) *

QUOTE(andys @ Aug 20 2008, 05:13 PM) *

Wilhelm,

Just catching up after 5 days in Puerto Vallarta, Mexico, thus the late post.

Nice work. Good to see someone thinking outside-the-box. I curious why you chose the 928 bearing? Most think the 914 bearing is more than adequate, and the 911 bearing beyond most needs.

I went with the 911 bearing mostly because it matched the late 911 axles, and I also moved the bearing further outboard in order to fit my 6 speed transaxle. Much like your work, here are a couple of photos of what I did (BTW, I can appreciate the amount of work that goes into this kind of thing). I fabricated a custom trailing arm.

Andys


From experience...


Junk the Wilwood spot caliper. If you set the brake when the rotor is hot, after it cools it won't release. You will end up beating the shit out of the caliper trying to get the park brake off.

Hi Clay,

I just ordered a set of Wilwood Mechanical spot calipers to make parking brakes for my V8 car that will have Boxster brakes with Rich Johnston adapters. Just to be sure I called Marty today at MSDS that runs them on his Turbo 914-6 car and they did a second car and he says they are perfect. I went over this with Eric Shea for a long time on the phone and he said as far as this thread went, it made no sense as the 914 brakes are really set up to be mechanical E calipers when we pull the handle.

Is this a red-hot racecar brake problem? Can it be the pads?

The only discontinued item on the web was a different number that the 120-2281,
120-2280.

Bob




Talk to Rich Johnson, and have him tell you about Mike Floyd's car. It was the one with the stuck park brake that got beat with a hammer to make it release.

burton73
Clay,

This was Rich’s answer to my email on the question. I guess we will need to see how Andy’s set up is going to work as it is done and Marty’s 2 set ups are working perfect for 2 years. I am a $100 in parts now so I can change out and sell what I have but I am looking for the easiest way for an E brake. I have seen Eric’s tread on the 911 set up but I do not know where to get the parts and how easy it would be to set it up.



“The problem Mike had was with the spot brake from Wilwood. It would hang when set for a period of time and Mike eventually went to the 911 based drum brake setup. I wouldn't base all systems on this one case Bob. I'm not sure the execution of Mike's system didn't contribute to this hanging issue. I will say that the drum system has been a much better setup and very OE looking vs. the mechanical look the levered spot brake had.

Rich”

charliew
Wilhelm I have been anxiously waiting to see the rest of your solution ie the spacers inbetween the cv's and stub. I have some 18x11 turbo wheels waiting. I may, to save the machine work just use the 914 bearing and hub and just move it out but the spacer will be interesting. I think it will need to be mild steel to have 6 threaded holes for the cv and 6 more counterbored for the stub flange. Might as well make it the length you need to use the axles you have. I haven't looked close but it looks like the inside of the new wide wheel is just about where the stock wheel is. I hope the wheel wells are not any closer than the control arm.
Looks great sofar.
Wilhelm
I'm anxiously awaiting the solution too! It has been miserably cold here and in fact is snowing again. The "shop" (barn) is unheated, work has been soul sucking, the children needy, the wife has the projects list (whine, whine, whine)...... I have the engine and tranny in, one of the half shafts is sitting in the hub and I was planning on tomorrow going out and running the suspension through its full range to see if I will need a spacer versus just purchasing longer axles from Sway-a-way. The deciding factor will be if the axle has enough room when the suspension is in full extension. Then it comes down to money and time. Probably cost me $100 in material and my time to make the spacers versus $300 to just purchase a pair of longer axles Swayaway Axles. God and my wife willing I will make a decision tomorrow!!!!!!!!!!!
charliew
Oh yeah I forget about the weather everywhere but here. It was 37 with 30 mph winds sat and I tried to find a doe I liked but the only good ones were by the gate as I drove out and my rifle was in it's case unloaded in the back seat of my sub. It's 30 this morn. and no wind, perfect except that sun is my wifes only day off and we go to ihop and my son just got back from san fran. and we will eat with him and his girlfriend and visit.

Do 914 guys ever use shorter shocks to limit droop? I don't know how much motion you need but it doesn't seem like more than 4 inches at the wheel, I don't know these little cars that well. Also would it not be cheaper to just open the inside of the control arm up the required amount? I would like to run my axles angled to the front some and that will agrivate the problem even more. That also means I will need swayaways probably. Unless I find the longest 911/944's I can get and just go with that. I still need to study up on computing the proper axle length to fit in the cv's to keep them centered for whatever I decide on. It seems the 944 may be the longest stock one available. Course I guess I could shop for some used custom ones.

I use a motor oil and juniper wood stove in my shop some but I also have my old 3 ton house electric heater but it really runs the bill up. We are just now getting into our cold season.

My wifes been patiently waiting on me to redo the kitchen cabinets for 6 months.
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