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914World.com _ 914World Garage _ Correcting the rear wheel to fender offset.
Posted by: Jonny Retrofit Sep 16 2021, 12:11 AM
Hi Guys,
We are running 8 x 15 Fuchs on the back of our narrow body '14. With careful tyre choice and a mild fender pull this works great on the passenger side of the car. On the driver side, however, there is 5mm less clearance which appears to be a common issue.
The wheels look great and I want to keep them so have been thinking about how to correct this offset. One option would be to modify the trailing arm front pivot tube. E.g. shorten on the inboard side and lengthen outboard, bringing the arm in by 5mm.
Any thoughts on this approach with respect to the suspension geometry? The only thing I can think of is that the damper would be at a slightly different angle but I can't see 5mm across the length of the damper making that much difference. We don't have a rear ARB. Pretty sure the driveshaft has enough slack to cope with the 5mm reduced distance.
Thoughts welcome!
Posted by: SirAndy Sep 16 2021, 12:35 AM
Just pull the drivers side fender some more. Much quicker and cheaper than trying to refab the suspension.
I take it you already rolled the fender lip?
Posted by: Jonny Retrofit Sep 16 2021, 12:49 AM
Just pull the drivers side fender some more. Much quicker and cheaper than trying to refab the suspension.
I take it you already rolled the fender lip?
Already pulled, rolled and car is painted. The rub is not on the lip, it's about an inch above that.
Posted by: Jonny Retrofit Sep 16 2021, 12:58 AM
This side is fine:
Posted by: Optimusglen Sep 16 2021, 08:21 AM
You going to shorten the axle 5mm too? Or potentially deal with binding?
Posted by: mskala Sep 16 2021, 08:43 AM
Unsure of your goals and restrictions, but given that running stock 8x15
is pretty far outside of the 'guarantee I can get it work' zone, my suggestion
is just add camber if you have a bit of space on the inside. Budget for
replacing tires a bit more often, but our cars are so light anyway I get pretty
good wear runnig max camber with 7.5" wheels.)
Posted by: Shivers Sep 16 2021, 09:20 AM
Out of the box. Is your 914 some kind of fire breathing monster, or is it a cruiser with a 1.7. Reason I ask is, would it be possible to remove a bit from the mounting face on the wheel and the rotor hat? If it is a hard driven high powered 914, never mind.
Posted by: brant Sep 16 2021, 09:23 AM
Unsure of your goals and restrictions, but given that running stock 8x15
is pretty far outside of the 'guarantee I can get it work' zone, my suggestion
is just add camber if you have a bit of space on the inside. Budget for
replacing tires a bit more often, but our cars are so light anyway I get pretty
good wear runnig max camber with 7.5" wheels.)
I agree..
multiple people have built the different swing arms you describe.
a ton of work... not realistic unless you are competing in a specific race class
much less brain damage to:
-realign
-change wheels
-add spacers and pull the fender
Posted by: LefthandRev Sep 16 2021, 10:30 AM
Just pull the drivers side fender some more. Much quicker and cheaper than trying to refab the suspension.
I take it you already rolled the fender lip?
What Andy said. I have super minimal clearance on my driver's side, but passenger's is fine.
How I test it after pulling, I got from watching the RWB mini-docs. Jack the car up, put a wheel or ramp under the wheel in question, then lower it down slowly until the car is resting on the object: Three wheels on the ground, one up. You should be able to slip a screwdriver along the length of the gap without issue. If not, put it back on the ground and pull it some more.
Posted by: Jonny Retrofit Sep 16 2021, 10:45 AM
Just to be clear, I don’t want to narrow the arms - agree that is a big job. My plan was to cut and shut the front tube part of the arm where the spindle goes through, thereby offsetting the arm inboard by 5mm. This would not be that hard to do and would have the same effect as moving the mounting point (which I can’t do because of already welded in strengthening)
The car is a 300HP EV conversion with a Tesla drive unit. Has some power but it is also heavy for a 914 at 1250kg. I need the car to squat to get the power down. Have already got a fair amount of camber.
Posted by: jcd914 Sep 16 2021, 10:59 AM
The suspension is precisely aligned with the centerline of the car and changing a single control arm will upset the balance of the suspension.
The fenders were not so precisely aligned and the clearance issue is due to the fender placement not the control arm placement.
Good luck what ever path you chose.
Jim
Posted by: horizontally-opposed Sep 16 2021, 11:05 AM
Agree with others—the right move here is, unfortunately, widening that fender.
You don't want to affect suspension geometry, particularly on only one side of the car, to get tire clearance. You're messing up more than you're gaining.
If it's a matter of getting the tire closer to the inner fender, and you can do it on both sides of the car equally, you could look at wheels with custom offsets. Or, if someone really knows what they're doing (i.e. an engineer and materials expert), you might be able to take a bit of the padding off of the back of the wheel. I wouldn't trust "just anybody" in messing with that, though. Your life, and others', are worth way more than whatever getting a paint gun out will cost.
Especially if the car is having trouble putting the power down. That tells me it's quick. Sounds like fun, and I've love to learn more about your car! 
Posted by: mrholland2 Sep 16 2021, 11:12 AM
Just to be clear, I don’t want to narrow the arms - agree that is a big job. My plan was to cut and shut the front tube part of the arm where the spindle goes through, thereby offsetting the arm inboard by 5mm. This would not be that hard to do and would have the same effect as moving the mounting point (which I can’t do because of already welded in strengthening)
The car is a 300HP EV conversion with a Tesla drive unit. Has some power but it is also heavy for a 914 at 1250kg. I need the car to squat to get the power down. Have already got a fair amount of camber.
Is this the one from the TV show??
Posted by: infraredcalvin Sep 16 2021, 12:18 PM
Although I'm not a fan of stretched tires, they appear to look good on fuchs on this car. I'd like to see more pics of the car please!
Posted by: Jonny Retrofit Sep 16 2021, 01:04 PM
Yes it’s the car that was on Vintage Voltage. I will start another thread with some pictures, in the meantime, there are pics on IG. Link below.
https://www.instagram.com/p/CT34qxVI5ae/
Posted by: Superhawk996 Sep 16 2021, 01:07 PM
This side is fine:
Danger Will Robinson. 205/55 tire on an 8" rim are well outside Tire and Rim Association guidelines. Widest is 7 1/2" width, with recommendation for 6.5" wide rim.
Lot's of bad scenarios ranging from debeading at speed to blow out from overheating of sidewalls.
Posted by: mepstein Sep 16 2021, 01:08 PM
This used to happen all the time at the shop where I worked. Not checking dimensions until the car was painted.
My first step would be to contact a good PDR guy and see if they can work their magic to make the clearance.
Second choice would be to call the guy who pulled the fenders and have them pull it some more. Fix the paint if it cracks.
Posted by: mepstein Sep 16 2021, 01:10 PM
This side is fine:
Danger Will Robinson. 205/55 tire on an 8" rim are well outside Tire and Rim Association guidelines. Widest is 7 1/2 with recommendation for 6.5" wide rim.
Lot's of bad scenarios ranging from debeading at speed to blow out from overheating of sidewalls.
Yea. I was thinking that running 7’s would fix a lot of issues.
Posted by: Jonny Retrofit Sep 16 2021, 01:28 PM
This side is fine:
Danger Will Robinson. 205/55 tire on an 8" rim are well outside Tire and Rim Association guidelines. Widest is 7 1/2" width, with recommendation for 6.5" wide rim.
Lot's of bad scenarios ranging from debeading at speed to blow out from overheating of sidewalls.
‘Well outside?” Don’t think so, it’s only one tyre size away which is 10mm. In reality it doesn’t look stretched at all - picture is making it look like that.
Appreciate the advice on the suspension geo which was what I was
looking for.
TBH, being new to 914, I did not expect to have this issue. Just my bad luck that the wheel test fit was done on the side with the space!
Posted by: 914e Sep 16 2021, 01:35 PM
@http://www.914world.com/bbs2/index.php?showuser=19211 My rear fender clearance varied considerably. I didn't notice till after I had finished the body work and the car was in final primer and ready to paint. I measured both sides to the inner and found the one side was about 5/8" close than the other. The car has never been hit in the rear so from what I could tell so it must have alway been like this.
What I did was take a about 12" of a pine 2x4 and gave the whole piece a slight curve with a belt sander. The ends I rounded heavily, along with the long corners. This way no sharp edges would be pressing the primed fender. I used a second longer piece of wood against the inner structure and used a scissor jack to push the fender slowly out working back and forth slowly working the fender out to match the other side. It didn't crack the primer. This might work for you.
Posted by: rhodyguy Sep 16 2021, 01:48 PM
Try a baseball bat. Or in your case a cricket bat to ease the fenders a bit more.
Posted by: targa72e Sep 17 2021, 08:03 PM
I did similar to 914E but used plywood against the fender. As pressure from the jack was applied the plywood took on a curved shape. I was able to move the fender out with out cracking the paint as well.
John
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