Visiting my favourite GEO Specialist to do his magic - COG!!

Gibbo

Gibbo

Gibbo

OcUK Staff
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Hi there


Its a long overdue visit, but I am at COG for the day to have some new Porsche suspension goodies fitted along with a full GEO setup.

Cars current GEO is well a bit all over, due to wear and tear on suspension components and well use and trackdays.

So far we've diagnosed in the suspension overall the following needs to be done and is being done as I speak:-

Front suspension bump stops - These more or less destroyed, no doubt due to trackday use (heavy braking), thankfully the dampers are fine, no leaks or damage.
Front top mounts - They are nearly gone and with more front camber they will be destroyed, so being changed to the latest Porsche generation models.
Front Springs/Struts - Filled with stone, gravel, tarmec, no doubt due to council treating the roads by just putting loose chippings down. Does your springs no favours as the drainage hole block, causing drains not to work and springs sit in water making them rust and eventually snap. So all road debris removed, cleaned and all re-greased.

I shall post up what the GEO setting were and what the new settings will be end of the day. But with all these new fresh parts in can't wait to drive it again. :)


Here is a picture of it on the ramps at COG:-

ouoyf9.jpg




Many places can do a GEO, but so many places will just take your car and well put a GEO on it. Whats the point in this if parts of your suspension are worn or broken, the GEO will be lost the moment you drive down the road.

Some pictures of the things were finding along the way:-

Think Bumpstops have had it, next to new ones to show the difference

ht5jko.jpg



Springs cleaned, all stone chipps got out so drainage holes unblocked and all cleaned up and re-greased

29ks8es.jpg



Top mounts de-laminating, see the rubber seperating - NOT GOOD!

2a65hrc.jpg
 
Hi there


Front struts, springs with new bump stops and top mounts, all cleaned up and waxed ready to go back in. Both have been refreshed by the way. :)

30uphjt.jpg


11mau0g.jpg




Oh and we drove the car before we started this work and on the test roundabout the car as happy at a steady 27mph and pushing too 29mph caused push (understeer). To compare after Chris worked his magic on the Mustang it could do the same roundabout at 32mph, if the 911 can match that it shall be very impressive. :)
 
Looks like the work was needed.

I bet with the new parts and the right set-up it will feel like a new car.

Would be good if you had a way of measuring g-force to see what it can do around the roundabout!

What tyres are you using? Looks a bit like Pilot Super Sports in the first picture?
 
^JP^ said:
Looks like the work was needed.

I bet with the new parts and the right set-up it will feel like a new car.

Would be good if you had a way of measuring g-force to see what it can do around the roundabout!

What tyres are you using? Looks a bit like Pilot Super Sports in the first picture?
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Yes tyres of MPSS. :)

Car feels absolutely awesome, though something just broke in the rear, I am guessing its one of the rear drop links have no doubt snapped, gonna shine a torch in a bit and swing of the bar. :D

Though until I broke it rounderbout cornering speeds are a good 2-3mph better, but the car just feels even more planted, way more confident inspiring, more stable etc. Really looking forward to the track day and Chris from COG said he'd attend it too so we can make any adjustments necessary whilst at track. :)

In short the following was done:-

New Gen2 997 Top mounts.
New front Bump stops.
Front dampers checked, springs all checked etc.
New lower front arms fitted.
New front & rear ARBS fitted.

The result is the car now has:-

-1.8 negative front camber (-1.00 on left before and only 0.50 on right before)
-1.75 negative rear camber (-2.00 on right before and only -1.00 on right)
8.30 caster both front sides (7.50 previously)
0.00 toe on the front (0.04 toe out before)
+0.02 toe in on the rear, just makes its very planted and under braking. (toe was all over place in rear)
Front track widened by 18mm

Basically the car now has a slightly more aggressive GEO setup than a gen2 997 GT3, but only margin, result is the car is better in every situation, even less road noise as all Porsche parts used, until something broke, which I am guessing is one of the rear links, we did notice they could be a weak point, but let me check and comeback on that.

In short car turns in better, has way more grip both front and rear in both left and right turns, accelerates and stops straight with zero dive. Car handles bumps and uneven surfaces better and the damping felt better and the car just felt tighter and quieter, no more jiggling about at all and it handled superb before even with the GEO a bit all over, hence why you should re-check GEO often or mark all your bolts to ensure nothihg has moved which has now being done. :)
 
It's centre mavity so not sure why you call it COG. You been playing too much gears of war.

Reminds me I need to get my geo (geometry) checked at WiM (wheels in motion)


Oh and growing up in Atherstone I know the roads well:p
 
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^JP^ said:
Sounds good, how do you think the tyre wear will be with those settings?
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Shall be improved!

Before I was cornering right on the tyres edges, I was basically using all the tyres and beyond, so excessive outer wear. Now the car uses the tyre far more effectively, hence improve wear as more even. :)

Had a tug at the rear bar, its either not that or I can't pull it hard enough.

When we put it together Chris pointed out the rear lower arms were starting to getting a little play and would be due replacement soon and he mentioned the rear drop links he was not 100% happy with them and they might bind and need some adjustment. So what I can only describe as what sounds like something moving in the back as in something come loose. Shall get it up on ramps tomorrow and have a good look. Good think is everything is marked so if something has come loose, in theory tightening back up to where the markings are will keep the settings bang on or at least I can easily adjust myself on anyones GEO machine within reason.

So a good day, car handled great but looks like either the rear drop links or lower arms need replacing. Not the end of world, rear drop links are about £60 for the par and if its rear arms, well both is sub £200.
 
Was it not once referred to on Chris' page as 'centre of mavity' hence the COG abbreviation Simon?

Has Chris got a new workshop now? Looks very different to all those years ago when I first went!
 
Housey said:
As I have said several times 911's are very sensitive to geo, even the gay ones like yours ;)
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It handled superb mate! A nice improvement, looking forward to Donnington. :)

Just don't want to risk pushing it knowing that something is jiggling about in the rear, I only noticed it because I heard it after doing some serious hard driving on my favourite roads so either something has come loose or a weak point has being found in the suspension which needs replacing. I suspect its the lower rear arms as he said they'd need replacing in coming months and maybe the GEO has just well accelerated their death.

Chris drove it and he said for a C2S if felt very alive, he commented to drive it felt far more like a GTS if not better. :)

Just wish it had developed this noise whilst on the test drive, at least its happened before the track day.
 
Gibbo, would Porsche 997 Carrera 2 S with Aero Kit describe your car? And what year is it if you don't mind me asking? I know you have the warranty, what year of car is likely not to have it?
 
Simon said:
Reminds me I need to get my geo (geometry) checked at WiM (wheels in motion)
Click to expand...

Which one?

I went to the new one in Milton Keynes (branded under a different name but same guys)

Very impressive space. Tony was showing me the work in progress for the fully automated wheel refurb line, totally hands off from start to finish. Even said they could give a 1 day turn around on my S2000 AP2V2s even including a diamond cut face!

Bloody easy to get to off the M1 also :D
 
Hi there

All fixed, seems the rear anti-roll drop links were the culprits, but it turns out they were just not tight enough, all fixed now! :)
 
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