Wider is better for cornering, everyone knows that.
If that's the case, why did Porsche engineers leave so much usable room under the front fenders?
Was it because they adapted some other cars geometry to the 914?
I have seen wheel spacers for our cars, have many of you used them to widen the track of the front end?
I don't race my car and it would just be for esthetic value but I have considered putting spacers in to "fill out the front fenders" but was wondering if it would screw up some other front end geometry.
What do you think?

I've been wondering about the same thing!

Front suspension is pure 911 design, hence the two can be interchanged between 1969 and late 70's. The 914/6 was a 911 suspension.

The rear is unique to the 914 and had to fit around the engine and transmission.

QUOTE (tracks914 @ Nov 3 2005, 02:09 PM)

If that's the case, why did Porsche engineers leave so much usable room under the front fenders?

Space your front wheels out to the edge just like the rears. Then go start taking corners really fast and you'll see why.

Wait, that was a retarded answer on my part.

When you turn your wheels and take a corner at the limit of the car (Compressed susp) the tire will either get chewed up by the fender or the tire will kick the fender lip out.

QUOTE (Root_Werks @ Nov 3 2005, 03:44 PM)

When you turn your wheels and take a corner at the limit of the car (Compressed susp) the tire will either get chewed up by the fender or the tire will kick the fender lip out.

naaa, think about that again ...

i run spacers in the front, about a (fat) fingers worth of space between the fender and the tires, car lowered. many, many AX runs, and i never had the tires rub on the fender ...
Andy

I'd have to say one reason could be safety....an understeering* car is generally safer for the "regular" public

*front end pushes instead of the rear swinging out

QUOTE (Mueller @ Nov 3 2005, 04:09 PM)

an understeering* car is generally safer for the "regular" public

"normal" drivers tend to let off the gas when they encounter loosing grip.
in a understeer situation, this will result in gaining control of the car again, in an oversteer situation this will result in a spin ...

Andy

QUOTE (tracks914 @ Nov 3 2005, 03:09 PM)

If that's the case, why did Porsche engineers leave so much usable room under the front fenders?

It's really very simple. The front wheels turn. The rears do not. The extra room is to allow the front wheels to turn.

QUOTE (Demick @ Nov 3 2005, 04:28 PM)

It's really very simple. The front wheels turn. The rears do not. The extra room is to allow the front wheels to turn.

i run a 1 1/4" spacer in the front and my wheels still turn ...

Andy

QUOTE (Demick @ Nov 3 2005, 03:28 PM)

QUOTE (tracks914 @ Nov 3 2005, 03:09 PM) If that's the case, why did Porsche engineers leave so much usable  room under the front fenders? It's really very simple. The front wheels turn. The rears do not. The extra room is to allow the front wheels to turn.

Your rear wheels don't turn? Is that cos the car is on jackstands???

lmao

I agree with Andy. I run a 205-50 on a 7" 911 offset wheel with 911 struts and 1/2" spacers under stock fenders. My ride height is 4" under the frame rail. I autocross quite a bit and set decent times on Khumos. Wheels turn just fine, but will rub if you hit a large bump while turning tightly. Not enough rub to even leave marks on the tires, but enough to leave black marks on the insides of my fenders.

Kelly

Slight thread hi-jack.

Andy, are you using a 27mm+1/4" (4mm) spacer to get 1 1/4" (31.75mm) spacer? What length studs are you using? I'm looking to put flares on my car so I can run 8's on the rear and then space the fronts. Is my only option for studs to buy 100mm's and then trim them down?

Kelly

Can you put a 3/4" or 1" spacer on the stock hub with stock Mahles and not hit/rub the fenders?

Depends on your fenders. These cars weren't all the same when they left Karmann, and they're certainly not the same now 30-35 years later. The rear fenders show wide variation from side to side and car to car, and there's no reason to think the front fenders are any different. On my first 914, I could fit my pinky between the tire and rear fender lip on one side, but my first two fingers fit fine on the other side, and there was no evidence the car had been hit, and this didn't change with a good alignment. My second 914 shows a smaller variation, but the wide fender is on the other side.

My rear fenders are the same way. I can only (barely) get my pinky inbetween on the driver side but almost 2 fingers on the PS.
The fronts seem a little more equal but I can almost get 3 fingers in on both sides. (the fenders that is)

As mentioned before a car with a narrower front track will be safer for most of the population. Many front wheel drive cars can spin should you lift of the throttle in a heavily loaded corner as well as under trail braking. OUr cars can do the same if you exceed the traction limits while coasting or under braking. Next time you are out run around a nice cloverleaf on ramp and play with speed and braking to see how your chassis reacts to different inputs.

When you go adding spacers to your hubs you increase the scrub radius. Increasing the scrub radius will make the car do some weird things. The contact patch will tend to move in bump, rotational torques will increase in single wheel bumps, bump steer can increase. Increasing the scrub radius can also lead to roll understeer.

Now increasing the front track is very benefical. It decreases weight transfer from side to side. It can also increase later acceleration (grip). The proper way to increase front track is to lengthen the a-arms and move the upper strut mounts outward. This will require some fab work.

QUOTE (blabla914 @ Nov 3 2005, 04:49 PM)

Andy, are you using a 27mm+1/4" (4mm) spacer to get 1 1/4" (31.75mm) spacer?

100mm studs in the rear, 74(?) mm studs in the front, spacer in the front is 1" + 1/4 " ...

Andy

QUOTE (Brett W @ Nov 3 2005, 07:55 PM)

When you go adding spacers to your hubs you increase the scrub radius. Increasing the scrub radius will make the car do some weird things. The contact patch will tend to move in bump, rotational torques will increase in single wheel bumps, bump steer can increase. Increasing the scrub radius can also lead to roll understeer. Now increasing the front track is very benefical. It decreases weight transfer from side to side. It can also increase later acceleration (grip). The proper way to increase front track is to lengthen the a-arms and move the upper strut mounts outward. This will require some fab work.

How much does increasing the front track with spacers, therefore changing the original scrub radius, affect steering effort? When going from the stock 5.5" wide wheel, to a 7.0" or 8.0" wheel or to spacers you're moving the wheel ceneter line further away from the steering axis which is going to require more steering effort. I'm just curious how much it increases.

It's all about costs. $$$

The 914/6 uses 911 hubs and brakes which result in a wider
front track, just as the designers and engineers wanted.

The lower cost 914/4 (4) lug uses VW parts bin brakes and
rotors which result in the narrower track.

It's just that simple.

QUOTE (SirAndy @ Nov 3 2005, 03:32 PM)

QUOTE (Demick @ Nov 3 2005, 04:28 PM) It's really very simple.  The front wheels turn.  The rears do not.  The extra room is to allow the front wheels to turn. i run a 1 1/4" spacer in the front and my wheels still turn ... Andy

Andy man, look at your pic in your avitar! I don't think you have to worry about too much suspension travel allowing a tire/wheel tucking too far up into the fender.

Yeah, okay, there are more than just one reason. Understear is easier to deal with than over steer to the general public. But I still think part of it is designed so that tall thin tires of the day wouldn't rub into the fender arches when the 914 was pushed to it's limits. But I could be wrong.

Thanks Andy.

I used to run a 21mm spacer under my front wheels with stock 914-4 struts and brakes and it worked great. Take some measurements yourself and I think you will find about 20mm is what you need to get things even.

Another excellent point is you have to be careful about tire diameter. I run a 205-50 which is only about 22" in diameter. If you tried to run a 205-60 which is like 25.5" in diameter with my rim/spacer/camber/ride height setup I think you would have serious problems.

It is true that using a spacer increases the scrub angle, but in our case the benefits far outweight the penalty. The steering does get heavier. Don't even consider smaller than approx. 14" diameter steering wheel if you want to drive on the track for any period of time. If you are in really good shape it may not be a problem. If the weight of the steering really bothers you, reduce caster. Just beware you will sacrifice some high speed stability with reduced caster and you may need more static camber to make R compound tires work well.

Just to clarify, the 914-6 front end will not improve the scrub radius. If you compare 914-4 and 914-6 struts and brakes I think you'll see that the only reason the -6 had a wider front track is the hubs are wider. Adding spacers and making the hub wider have the same effect on scrub radius. The only way to widen the track without effecting the scrub radius is to move the ball joint out and move the strut attachment points out (or just run a LOT of negative camber) to match.

Kelly

I run 15x7s with 205x50 Avons which are even bigger than the Hoosiers and I have no clearance problems in the front.