Lower the front end

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dana914
Posts: 36
Joined: Sun Feb 17, 2002 3:01 am

Lower the front end

Post by dana914 » Tue Apr 02, 2002 7:23 pm

I want to lower my front end to match the rear height. Any suggestions would be appreciated. Thanks

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Bleyseng
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Joined: Fri Apr 21, 2000 2:01 am

Lower the front end

Post by Bleyseng » Tue Apr 02, 2002 9:08 pm

There is a 11mm bolt that is on the torsion arms for that adjustment. Spray it first with some PB Blaster and then turn it to adjust the height up or down.
The other thing to look at is if your rear springs are worn out. If they are the orginal 80lb springs they are shot. Get some 140lb springs and enjoy the ride improvement. You can also adjust the rear with adjustable rear shock perches
Geoff


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76 914 2.0L

kevin powers
Posts: 216
Joined: Mon Dec 24, 2001 3:01 am

Lower the front end

Post by kevin powers » Tue Apr 02, 2002 10:15 pm

how much of a diff is there? measure at the points where the rocker pannel meets the wheel well at both ends. as far as body lines go this is a pretty common reference.an even stance makes for a pretty well balanced car. if you go too low you will have to make other changes as well.also make sure that your gas tank is full, the spare is in the front and the air preasure in the tires is correct.

[This message has been edited by kevin powers (edited 04-02-2002).]

Zeke
Posts: 259
Joined: Fri Jan 18, 2002 3:01 am

Lower the front end

Post by Zeke » Tue Apr 02, 2002 10:27 pm

And lift the front allowing the suspension to drop to full droop before adjusting the bolts. Lower the car, roll it back and forth several feet, bounce it, check height and repeat until you get it where you want it.

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Milt 914 2.0 Race Car (under construction)

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Racer Chris
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Joined: Sun Jan 13, 2002 3:01 am

Lower the front end

Post by Racer Chris » Tue Apr 02, 2002 10:34 pm

You may also need to add steering rack spacers to eliminate the bump steer effect.

Chris F.
www.tangerineracing.com

Zeke
Posts: 259
Joined: Fri Jan 18, 2002 3:01 am

Lower the front end

Post by Zeke » Wed Apr 03, 2002 12:26 am

Right on Chris! Hey, where you been, man? Bump steer. Is that when you steer around bumps?

dana914
Posts: 36
Joined: Sun Feb 17, 2002 3:01 am

Lower the front end

Post by dana914 » Wed Apr 03, 2002 2:47 am

Thanks all, I'll look at it all. Looking for a level ride.....

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Racer Chris
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Lower the front end

Post by Racer Chris » Wed Apr 03, 2002 8:27 am

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by zeke27:
Right on Chris! Hey, where you been, man? Bump steer. Is that when you steer around bumps?<HR></BLOCKQUOTE>

Hi Zeke,

I pass through quietly almost every day, looking for a chance to be useful.
Another thing to help with lowering the front end is modifying the struts to raise the spindle. I cut the bottom off and add a length of tube, then reweld the bottom in place. Next I remove a corresponding section of the tube above the steering knuckle to maintain the original length. Finally I heat and bend the steering arm to compensate for the relocated knuckle position. It is important to keep the tube very straight and smooth inside so a shock absorber still fits in.
Some 911 struts are easier to modify because the tube is straight, so one can merely drill out the weld that holds the knuckle in place, then slide it up and reweld.
I can provide this service to anyone interested.

Chris F.
www.tangerineracing.com

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Dave_Darling
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Lower the front end

Post by Dave_Darling » Wed Apr 03, 2002 12:52 pm

And yes, "bump steer" is where the car changes direction when you go over bumps, even though you hold the wheel straight. When you lower the front end past a certain point, you wind up getting toe-angle changes as the wheel goes up and down. This will tend to steer the car.

Raising the steering rack upwards will restore the rack-tierod-wheel geometry and get you back to where toe changes are very small when you go over bumps.

Remember to loosen the U-joints on the steering shaft if you install the rack spacers (the "bump steer kit"). Otherwise they might bind up making the steering difficult in some spots. Extremes might even break the U-joints! When you get the U-joints to where they don't bind during the full range of motion of the steering wheel, tighten them up on the shafts again.

--DD

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1974 VW-Porsche 914 2.0 (Type IV powered!)

Pelican Parts' 914 Tech Geek http://www.pelicanparts.com

Zeke
Posts: 259
Joined: Fri Jan 18, 2002 3:01 am

Lower the front end

Post by Zeke » Wed Apr 03, 2002 1:50 pm

DD, I won't try any more tougne-in-cheek about bump steer. But, since you brought it up, don't you have to elongate the hole into the driver's comparment at the floor when you drop the rack? I would think you would have to remove the u-jointed shaft altogether. Right or wrong?

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Milt 914 2.0 Race Car (under construction)

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Racer Chris
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Lower the front end

Post by Racer Chris » Wed Apr 03, 2002 1:59 pm

Zeke,

Rack spacers raise the steering rack relative to the crossmember. No sheetmetal modification is required for the spacers to fit, but I think one thing Dave forgot to mention is the clamp under the fuel tank. It may need to be loosened also when installing the spacers. If you wanted to move the rack up much more than what the retail rack spacer product does, you might run into interference issues.

Zeke
Posts: 259
Joined: Fri Jan 18, 2002 3:01 am

Lower the front end

Post by Zeke » Wed Apr 03, 2002 10:46 pm

Right. Steering rack on top of crossmember. D'oh. Raise up, not drop down. D'oh2(squared) But the original question wasn't that stupid was it? The splined input shaft to the rack will no longer be in the center of the hole in the floor. Do you use the boot?

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Milt 914 2.0 Race Car (under construction)

[This message has been edited by zeke27 (edited 04-03-2002).]

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Racer Chris
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Lower the front end

Post by Racer Chris » Wed Apr 03, 2002 11:42 pm

I would have to check on the boot, I don't remember now. I think it would fit ok. I have been through several combinations over the years. At one time I made up a set of spacers that were taller than the store bought ones. I have never actually checked the bumpsteer situation with a gauge. Never noticed a problem on the track either.
The big thing about moving the spindles like I described is that shock travel is restored, so bottoming out the shocks is unlikely. I typically move the spindle about 7/8". It is still possible to fit some stock wheels (like Fuchs alloys) without interfering with the ball joint. Bending the steering arm eliminates the need for rack spacers. It is a bit tricky to get right. Another way used in 935 suspension kits is to replace the tie-rod end with a spherical rod end and use a long bolt and spacer between it and the steering arm.


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Chris F. :)

www.tangerineracing.com

Zeke
Posts: 259
Joined: Fri Jan 18, 2002 3:01 am

Lower the front end

Post by Zeke » Thu Apr 04, 2002 12:24 am

Whoa Chris! You bent the steering arm? With a torch I presume. Is that a forged piece? You're the metalurgist, I won't heat and bend anything untill someone (maybe two someones) tell me it's OK. Did you heat treat the thing after?

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Milt 914 2.0 Race Car (under construction)

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Racer Chris
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Lower the front end

Post by Racer Chris » Thu Apr 04, 2002 10:10 pm

The steering arm is pretty hefty, much stronger than necessary. I'm sure its OK to heat it to a medium red color to bend it and air cool. It's not high carbon tool steel or anything special so no heat treat cycle is necessary IMO. I don't get the spindle area hot enough to affect the stength there. A forged alloy like that won't get very soft from annealing anyway. Most of it's strength is in the chemical composition, not the heat treat. Another slight benefit from bending the arm is that it shortens the leverage, thereby increasing the steering rate. Image

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Chris F.

www.tangerineracing.com

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