Disadvantages of bigger diameter & lower profile (Heavier wheels)

[geoff Ives]

I have two cars of the same type and year, they are both 924S's. One is bog standard and one has very large wheels.
The standard one seems quicker on acceleration and easier to drive in town traffic. The 'Special' one is heavier in low speed response but sticks to the tarmac like a limpet.
Which is quicker ... The standard one in normal road situations. The 'Special' would, I think' lap a circuit quicker because you could leave braking later and you would not need to scrub of as much speed.
Which is better... Neither as I have both.

 

[924Srr27l]

I have two cars of the same type and year, they are both 924S's. One is bog standard and one has very large wheels.
The standard one seems quicker on acceleration and easier to drive in town traffic. The 'Special' one is heavier in low speed response but sticks to the tarmac like a limpet.
Which is quicker ... The standard one in normal road situations. The 'Special' would, I think' lap a circuit quicker because you could leave braking later and you would not need to scrub of as much speed.
Which is better... Neither as I have both.

Excellent Geoff, I can't see the Pictures but what wheels and tyres do they both wear?
Interesting you mention the steering on the Special? is heavier but the car sticks well, does this mean the stock one slides easily or just rolls more, and
are they both Manual steering ?

R

 

[944 man]

Has this wally really stated that he drills wheels to lighten them?

 

[Monkeythree]

Has this wally really stated that he drills wheels to lighten them?

From his website:

"Step 1 & 2: Machine the centre flat, it looked like it had plenty of meat there and besides this
car would be 23% Lighter so I figured the strength would still be good ! Drill 10 holes for
semi aesthetic reasons / tiny weight loss"

Precision engineering at its finest.

 

[geoff Ives]

Excellent Geoff, I can't see the Pictures but what wheels and tyres do they both wear?
Interesting you mention the steering on the Special? is heavier but the car sticks well, does this mean the stock one slides easily or just rolls more, and
are they both Manual steering ?

R

I've managed to get the image towork.
The standard car is just that. The Porscheshop Project car is in a garage away from home and I will let you know the wheel/tyre sizes when I can get to it.
G

 

[924Srr27l]

Has this wally really stated that he drills wheels to lighten them?

Oh hello again, Yes I got inspiration from some Japanese multi drilled wheels like you often see on
Subaru's and Mx5's etc...also some Ford styles have Religious Spokes too (Holy)

I had to source and buy 3 sets of 16" Cup wheels to not only get all (4) in 7", but also straight rims.

Chemical paint strip / Machine flat the centre,

Then, ruler, magic marker, centre punch and drill away specifically calculated by (Cranberry university)

Then the hard bit, Powdercoat Primer / wet Solvent colour / CNC lathe polish (Diamond cut) and (Dry Gloss Powder lacquer) & Final bake @ 200degs

R

 

[924Srr27l]

I've managed to get the image to work.
The standard car is just that. The Porscheshop Project car is in a garage away from home and I will let you know the wheel/tyre sizes when I can get to it.
G

I see the "shaken but not stirred" car (Martini) they look like 17"? and road tyres

I tried a set of 17's on mine but even though they were probably lighter than yours it killed the acceleration,
and affected the braking and handling adversely compared to the 16's, so I sold them on.

R

 

[924Srr27l]

- (8) transaxles in 16 years (924's / 944's & a 968)
- 20 different sets of wheels have been tried and tested (All on the Road)

- 8 sets on a 924
- 4 sets on a 968
- 4 sets on early 944
- 4 sets on oval dash 944

Here's a few..........

Wide Boy

Lift & Drift

Not mine, but a customer who wanted the Carerra GT Look

Tatty and tired 924S £500!! ebay purchase 2010, with 16" 986 wheels

All show and no go, very very heavy replica low offset cups 88kg!

Very light 15" Cookie's

More Heavy replica's

18" Cayman wheels, light for their size

Lightweight BBS 17's

BMW 850 BBS Splits 17"

BBS 986 17"

6x15 teledial's

15" 932

16" 928 Front / 924 15" rear

8x16 cup / r888 set

R

 

[944Scott]

I hope you have informed your insurance company of this modification.

 

[924Srr27l]

I hope you have informed your insurance company of this modification.

Great Scott !

Oops I did it again! you got me thinking now,

What about the flimsey fibreglass sunroof panel ? the drilled Torsion tube ? the handbrake shoes delete?
the Racing Engine, tiny mirrors, plastic back window, bespoke welded coilover struts, non standard brakes, cut inlet manifold etc..etc...

Yeah don;t worry, the 250 images website, 8 pages of PDF Excel sheets detailing the extensive 4 year build, Bill of materials,
Costs breakdown, detailed modification & Restoration 30K costs have all been seen, evaluated and an agreed value set on replacing them all or the whole car.

Specific Insurance was on the agenda, good job I'm on the Ball Brains FAB....

R

 

[924Srr27l]

More............

R

 

[blade7]

£30k......

 

[924Srr27l]

£30k......

Yeah I know you could buy a couple or three Blade's for that or this tasty RC30

And she's a Beaut.........No question, (The Honda's nice too.....lol)

4 year project / spend, @ £7500 a year....Some people easy spend that on coffee, beer and Fags !

I know i've burnt 30K on Women with nothing much to show apart from a CV list of Ex's and 5 kids!

I've easy spent and lost 30k on other cars over 26 years, and spent the same again if not more
on Racing for 10 years.... Money doesn't go far when you start getting involved in
expensive automobile hobbies if you want to win and build the best.

Work & labour from 7 Different Companies (2 in the USA) doesn't come cheap, Porsche parts are well famous for
being pricey!
The Genuine Engine Mounts and a just an OE Water Pump was nearly £600 alone! the LSD £1000,
it all adds up quite rapidly.


Here's a brief summary, (This may contain flashing images and some people may have to sit down!)


Engine & Eng Bay items £8652
Gearbox & Trans £1600
Fuel System £187
Suspension £3217
Exhaust £700
Brakes £2009
Interior £1325
Exterior Body & Panels £2329
Wheels & Tyres £1227
Labour £6325
Paintwork £2780


Total £30,351

R

 

[geoff Ives]

£30k......

Yeah I know you could buy a couple or three Blade's for that or this tasty RC30

Or 10 of these...

 

[geoff Ives]

Or....
4 of these....

 

[geoff Ives]

Or 3 of these.....

 

[blade7]

£30k......

Yeah I know you could buy a couple or three Blade's for that or this tasty RC30

And she's a Beaut.........No question, (The Honda's nice too.....lol)

I'd much rather have an RC45.

 

[924Srr27l]

blade7
I'd much rather have an RC45.

Nah, my passion for 2 wheels is over, 14 bikes I've survived (just)......... Only 4 wheels for fun now.

R

 

[924Srr27l]

This is an Interesting Clip, Chris Harris decides to try 4 Skinny Space Savers on an AMG Merc

https://www.youtube.com/watch?v=HPh90yNX-mY

R

 

[Indi9xx]

A highly complicated subject and like almost anything in engineering component design, every option has advantages and disadvantages, some of which can be enhanced or mitigated with redesign of other components with every assembly being the sum of its parts.

In my opinion, a 944 or 968 on the road is more nimble and stable on 16 inch wheels, partly due to unsprung mass and flywheel effects, partly due to the suspension and steering components as an assembly were developed to work well with 15 or 16 inch wheels. But on a smooth track, at higher speeds (or Autobahn as TTM mentioned) 17 inch wheels (with the right caster mounts) can be a better all round package.. But take that car down a country lane and the 16 inch wheels will see the car more stable over the rough surface and more nimble.

A 991 GT3 has truely massive wheels, to go over the top of seriously massive brake disks, but also to heat sink some serious heat, but with a suspension package, including the hub and the wishbone, which has been designed as a package that works well for its intended application.

A 968 Turbo RS had 18 inch speedline split rims, but the 968 Turbo RS was again designed for its hunting ground to be smooth and fast GP Circuits, not the B346 on a wet sunday morning.

I am all for modifying Porsche cars as many of you will know, but sometimes, Porsche did a pretty good job of specifying a car correctly for its intended market and environment which model by model, is pretty diverse. However, if you want to use the car in a different way to the masses at time of production and have a different set of expectations and requirements to those masses, then modification is the way to go.

Then there is the cool factor.. Cars do look cool with the right large diameter wheels, there is no getting away from that, but that is a completely different design criteria for a different audience, often at the expense of another dynamic.