924srr27L Lightweight Doors / Suspension / Bump steer etc..

[924Srr27l]

Strut Top ,

I've cut out a section from a breaker so that I can look at designing a Rubber Top mount

that will locate the Shock absorber piston rod 25mm higher and hence allow more movement

specifically for lowered cars.

Ground Control USA make such a mount but it's used with a Spherical bearing, and this would offer

no vibration absorption like the OE rubber Donut style does from the 924 & Early 944's

The underneath had the Underseal which I ground off and you can see the bronzy Zinc Galvanised Steel

and the Spot welding marks

I want a plate similar to this Golf one (below) but with more depth to house the Rubber mount higher.

Possibly a spacer to keep the Spring pan the same as OE, or the 2.5ID spring will fit through the

4" chassis hole if required.

I'm also hoping to get some quotes on Stainless Steel Strut tubes, threaded for Adjustable platforms

and the same design as the early 944's so any Insert can be fitted (Sach's , KYB, Koni, Bilstein, Spax etc..)

Early Stub axle sizes, although I may consider a Threaded bottom bracket and then the later type could also

be made if I consider making & selling them.

R

 

[geoff Ives]

Why don't you strip all the paint off.... That's what Mercedes did with their Grand Prix cars in the 1930's

 

[924Srr27l]

Why don't you strip all the paint off.... That's what Mercedes did with their Grand Prix cars in the 1930's

Yes, if it wasn't for my profession the car would be even lighter.. but I'm not a fan of the brown patina look!

And I wanted everything fully covered so I can drive come rain or shine, it's no garage queen...I've only

washed it 4 times in 3400 miles..



R

 

[tscaptain]

Now there's a first for me. I've never seen a wash per miles ratio before.[]

 

[924Srr27l]

Suspension

I' looking to have bespoke front struts made for me by UK Manufacturer AVO,

Because all of the other shock manufacturer's Dampers and spring rates are too stiff for my application.

They are also harder still as most are orientated for trackdays etc..and not road use.

AVO will be building me Steel threaded struts with the camber adjustable bottom bracket, upside down Mono tube Internals (Adjustable bump & Rebound) but with a lighter range of Valving, and shorter piston rods (Reduced travel) due to the lower ride height all to be used with the standard Rubber Top mounts and with Spring rates similar to a standard car.

R

 

[924Srr27l]

Progress:

Stub axle Extensions now made M18 Wishbone & M14 for the TRE...

(12.9 Grade High tensile Bolts & Spring Washers)

Ready to be welded in, and linked / triangulated, then Powder coated

New Steel Wilwood Caliper Brackets made to replace the current Aluminium versions which i think may be flexing..

- Wishbones at Fab shop being welded with Billet Threaded M18 bosses

- 4 Rod ends ordered (M18 & M14) 3 piece motorsport tolerance Stainless Steel

R

 

[robdimond]

Wow those bits are longer than I expected, is the car really lowered that much?

 

[924Srr27l]

Wow those bits are longer than I expected, is the car really lowered that much?

45mm from standard





They have been made on the longer side on purpose, with plenty of thread inside so I can cut them down if required.

The original wishbone balljoint stem sits 15mm upwards from the top of the wishbone.

My modified bones are being fitted with a male rod end which is positioned flush

hence the extension is 15mm longer than the actual required difference.

R

 

[John Sims]

This seems like a lot of trouble and expense. For such significant investment I am surprised there isn't an off the shelf solution available from the States.

 

[924Srr27l]

This seems like a lot of trouble and expense. For such significant investment I am surprised there isn't an off the shelf solution available from the States.

A big majority of people that lower their car, or fit incorrect offset wheels, or incorrect tyre sizes etc often claim their car handles "Mint" from such changes which, to a minority who have more feel and especially Racing experience know this is not the case.

No there isn't currently any "Off the shelf solutions", because as above there's no demand for such components because most road users don't think or understand there are any adverse issues and besides any such kit would be seen by them to be far too expensive and would not sell in any quantities.

These modifications are something done more so on dedicated Race cars, but they will also benefit massively lowered road cars for a

select few that are more technically minded and / or performance driven and prepared to pay for bespoke work etc..

For me and a few others seeking such avenue's (Modifying Road cars for performance not looks) it's not a lot of trouble or expense at all, quite the reverse.

It's a buzz to learn , understand, constantly improve and engineer better performance solutions with modifications which from experience will improve the car.

R

 

[blade7]

Who knew, Adrian Newey has a sideline refurbing wheels.....

[8|]

 

[924Srr27l]

R

 

[Eldavo]

This seems like a lot of trouble and expense. For such significant investment I am surprised there isn't an off the shelf solution available from the States.

There's an off the shelf solution available from Germany For all this trouble and expense.

Its called a 944 Turbo []

 

[924Srr27l]

This seems like a lot of trouble and expense. For such significant investment I am surprised there isn't an off the shelf solution available from the States.

There's an off the shelf solution available from Germany For all this trouble and expense.

Its called a 944 Turbo []

Buying a 944 Turbo (I'm presuming you mean) may seem like a easier & better performing solution to some, but to me it can also

be seen as a shallow / defeatist attitude.

Imagine if such a challenge to modify an normally aspirated car to surpass a turbo model's performance was achievable?

It is, and I've done it!



You only have to look at the stock 944 S2 v turbo debate which for many the S2 often wins as a road car, now imagine such a car that

is quicker than both of these and also the 968?

Have you never seen an Historic Race between a classic Mini and an American V8 with hundreds of horsepower? the mini often beats

the higher powered car, Pirelli 's Slogan "Power is nothing without control" is also a classic case in point here with the 924srr27L.

To consider stopping further developments and taking on another project with unnecessary costs would be a backward step,

and besides a forced induction engine will not drive as nice as an N/A. If you'd also driven and experienced one of the fastest

(road car) normally aspirated transaxles in the country you'd understand more.

I've not seen anything available (USA or Germany), to recalibrate the front suspension Geometry of a lowered transaxle, hence

I'm designing some and having it made.

It may seem like too much for some, but if you have the vision, experience, resources and budget man can achieve

many engineering solutions with ease and great success.

Or if your ECU is lagging and wants the easy route... buying a 944 Turbo is the way (apparently!) []

R

 

[edh]

The only off the shelf solutions all appear to be using longer pins. To my knowledge no-one makes modified hubs.

This lower arm might work - claims to have stronger pins than those retro fitted to a standard arm.

http://www.racersedge-inc.com/racersedge/rehome.nsf/0/065E61557E81DA2E8525718F00646D1F?open&id=9.3.10

I'd be interested to know what EMC have done to address roll centre correction, if they ever have..

Also - what about roll centre correction for the rear axle? - just wondering.. []

FWIW A friend of mine has just done this sort of mod to his very fast mk2 golf and commented on a marked improvement in handling.

 

[Eldavo]

Take a joke.

I'm pretty sure that after driving one of the fastest NA transaxle road cars in the country I would be decidedly underwhelmed and imagining what that amount of time and money could've achieved with something faster to start with.

I've driven an awful lot of powerful cars both modified and standard and I quite like Turbocharged engines. I've experienced just how fast 115bhp can be from the passenger seat of a friend's superlight race Caterham - but even he will admit that the chassis can take much more power and will be a far faster car. The same is applicable to the transaxles, the chassis can control and indeed deserves significantly more power than the NA engines can produce.

You can lighten it and it and tinker with geometry all you want but it will never be as fast or capable as if you'd started with a 944 Turbo - see Patrick and his friend Sean's car taking down 997 GT3s for example.

As it is you prefer a NA engine then fair enough, I can't help but wonder what you could achieve with an engine transplant though? An Audi 5cyl Turbo would be awesome Given the development of th rest of the car.

 

[924Srr27l]

Here's some good information / quotes from a select few that know their stuff in regard to the drivability of n/a and turbo engine 944's (From Piston Heads Forum 2009)

PaulJMcNulty Don't forget, in the real world of speed cameras and other drivers an S2 is plenty fast enough for most people. Things like alignment, suspension, tyres, brakes and driver ability or training will make you a lot quicker than bolting on a bigger turbo.

Baz (Hartech)

It is an interesting comparison and when I visited the Porsche factory some years ago - the chief engineer when asked which was the best car Porsche ever made - replied the 944 turbo. Having driven all models for years - I almost agree except that slight lag sometimes catches you out when overtaking and becomes irritating - and if you tune them up (which is easy) the pick up breaks the rear wheel traction and limits resulting performance - apart from which the car is brilliant. That is why we built a 3 litre version to try and provide the bottom end torque that the S2 has and reduce the snatch when the turbo power is delivered and although we have a little more work to do - this outcome has already been achieved.

We were not seeking huge power but expected that by combining the standard turbo and inlet system with a larger engine we would get better bottom end torque - a less agressive transition when the turbo cut in and at lower revs and therefore could utilise the 300 or so bhp more effectively and make a nicer car to drive.

The engines are not too difficult to build but many people then change lots of other things like turbos, waste gates, intercoolers etc and in so doing re-create a huge boost push again on the rear wheels when the turbo cuts in (which in my view detracts from the intention unless it is just flat out top speed you are interested in) and create a lot of re-programming problems.

Jon951 Having switched from a 220 model to a 250 earlier this year one thing I have noticed was that the 220 is less laggy due to the smaller turbo though it does run out of puff quicker. I had a dual port wastegate, different chip and a tweak to the boost on my 220 and on a dyno day she made 274bhp on what was regarded as an accurate and "conservative" dyno machine. Less lag too. I now have the same kit on my 250 and it makes a huge difference. The 250 does have other advantages as already suggested, mainly due to the gradual development of the model throughout its lifetime. Certainly would take a good 220 over a ropey 250 though.

Some people want as much power and punch as possible, however there's more to the best drivability

on public roads than a high top line figure. You can see a few times wheelspin and lag have been mentioned as issues, also the need for low down response / torque sought after and finally suspension & Brakes important to get the power down and most of all driver talent.

A low rpm torquey large bore / short stroke blueprinted race crank / mild cam and 20 piston brake system

low Centre of gravity corrected Geometry 50/50 weight transaxle that weighs the same as a Fiat 500 is exactly in this mold, less is more, drivability is eveything as a stable chassis and strong brakes are.

Comparable with a stock 944 turbo 220/250, it's not. with a modified one in stock trim would need to be 350bhp I think to be close, but even then it would be a close comparison.

Hence why Barry was not looking to produce a 400bhp+ motor due to the wheelspin issues, Lag and poor low rpm torque & response.

R

 

[924Srr27l]

The only off the shelf solutions all appear to be using longer pins. To my knowledge no-one makes modified hubs.

This lower arm might work - claims to have stronger pins than those retro fitted to a standard arm.

http://www.racersedge-inc.com/racersedge/rehome.nsf/0/065E61557E81DA2E8525718F00646D1F?open&id=9.3.10

I'd be interested to know what EMC have done to address roll centre correction, if they ever have..

Also - what about roll centre correction for the rear axle? - just wondering.. []

FWIW A friend of mine has just done this sort of mod to his very fast mk2 golf and commented on a marked improvement in handling.

Racers hardware The 944 front control arm has long been know to be a weak point in the car's suspension. Also, when drivers lower their car they throw the suspension geometry “Out of Whack” and thereby lose a lot of the improvement they are hoping to make.

Yes, thanks I've seen the Racers hardware wishbone and I'm sure this works very well, I just thought i could make something as good and hopefully not as pricey by modifying Porsche aluminium arms and using the best Rod ends i could find (£320 for 4) in combination with welding on permanently extensions on to a fresh pair of stub axles.

The plan is to do a big change all at the same time for maximum effect: replace the Wishbones / Stubs and adjustable damping struts with shortened (More travel) versions, lower spring rates and keep the rubber top mounts for compliance & comfort.

I'm not sure what EMC and other racers do, apart from the pictures in this thread of the highly modified

stub axle I've been lent which was from a very successful 944 racecar. Which has the extensions welded on and boxed in.

I think some Racers do nothing and / or are unaware that such changes would reap big benefits as you mentioned from your friend's golf I've heard and read nothing but a big improvement.

Yes good point about what about the rear, and my answer would be the rear of the car does everything I ask of it at the moment (It may misbehave when the front's sorted?) but I have no oversteer or wheelspin issues, it's the excessive roll on the front which I know is the altered roll centre and incorrect wishbone angle also the bumpsteer is causing issues so this will also be sorted in tandem with the new stub track rod end extensions.

R

 

[924Srr27l]

Take a joke.

I'm pretty sure that after driving one of the fastest NA transaxle road cars in the country I would be decidedly underwhelmed and imagining what that amount of time and money could've achieved with something faster to start with.

I've driven an awful lot of powerful cars both modified and standard and I quite like Turbocharged engines. I've experienced just how fast 115bhp can be from the passenger seat of a friend's superlight race Caterham - but even he will admit that the chassis can take much more power and will be a far faster car. The same is applicable to the transaxles, the chassis can control and indeed deserves significantly more power than the NA engines can produce.

You can lighten it and it and tinker with geometry all you want but it will never be as fast or capable as if you'd started with a 944 Turbo - see Patrick and his friend Sean's car taking down 997 GT3s for example.

As it is you prefer a NA engine then fair enough, I can't help but wonder what you could achieve with an engine transplant though? An Audi 5cyl Turbo would be awesome Given the development of th rest of the car.

I can't tell if your Joking, as (historically) your comments have been very adverse, personal and negative etc..

If you put a (LOL) or (Joke) after your comments i'll know in the future.

I like your comment that you'd:

Eldavo be decidedly underwhelmed and imagining what amount of time and money could've achieved with something faster to start with.

This is something I can clearly see is impossible to explain to you in a way that you understand it. I think I could try very hard (As usual) but it's really not going to work is it?

I could try and explain that a high power figure isn't everything, that a lower bhp figure but a Torque figure the same as the BHP in a chassis that responds so much better than stock due to various suspension & brake modifications with a huge weight loss make the overall package a far quicker road car than seeking a high top end figure.

Eldavo You can lighten it and it and tinker with geometry all you want but it will never be as fast or capable as if you'd started with a 944 Turbo

If I fitted a stock 220 or 250 Turbo engine in my car it would not be as good on the road as the 2.7 N/A.

If I bought a stock 220 or 250 944 car it would be even less as good (Heavier car, worn suspension and less powerful brakes etc...)

If i put a modified turbo engine in my car (300+ bhp) the car would be faster in a straight line, no different cornering but it would have a very different power delivery in and out of corners and wheelspin issues. Whilst these characteristics I'm sure would be fun they make the car harder to drive and slower on the road which is not my goal.

(Re Look at Barry Hartech's views on this thread)

R

 

[924Srr27l]

Eldavo] I can't help but wonder what you could achieve with an engine transplant though? An Audi 5cyl Turbo would be awesome Given the development of the rest of the car.

Nah, that's double cheating, Turbo and not a Porsche engine.

I'd rather build a spaceframe car with 944 panels and a Honda 1.8 Vtec Screamer with a sequential box.

R