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

[924Srr27l]

Anyone got a Complete Door they can weigh reasonably accurate pls ... ?
(Inc Doorcard, mirror etc..) So i can compare when I've finished making lighter doors......

I was considering Fiberglass but they don't fit very well.

So I've picked up some Steel doors which I'm going to Lighten further by drilling holes in them, also
removing inner and outer section Steel panels, and replace with Aluminium as the outer frame will fit
much better than the fibre versions.

R

 

[924Srr27l]

Bit more Progress today on one Door....

Marked, drilled and cut the front out and cleaned up all

the sharp edges, I was surprised this panel weighed as much as 2KG

Need to do the same to the other door then ready for the Fab shop to make, fit and rivet on the replacement front panel in aluminium

I might get them to add some swaged ribs and also I need to design, get fabricated and bolt in some aluminium X Door bars.

Then chemically strip or Shot blast off the Rivera? Blue, Powdercoat White and Solvent paint the (Front) Alpine White, & (Inside) Satin Black

I've also got some Early Script door cards, where I've cut off most of the card to only leave the top scripted piece.

Not sure yet where the inside handle will go, but I'll use stock external handles and latches and my current Lightweight Race mirrors.

I think they should be at least 15Kg (each) less than standard doors.







R

 

[944 man]

Unless your car has a full cage, and really it needs to be a welded-in multi-point, those doors will be absolutely deadly in the event of a crash.

 

[944Turbo]

some lightweight doors here but I think they didn't fit that well

https://www.porscheclubgb.com/forum/download.axd?file=0;641531

 

[924Srr27l]

some lightweight doors here but I think they didn't fit that well

https://www.porscheclubgb.com/forum/download.axd?file=0;641531

Are those GRP from Teilecar ? Club Autosport do them also and maybe they would fit reasonably

but they are of course made for Race use and "the Fit" is not a priority only the performance benefits...

Hence the fit is more important for my application as a Floppy door swinging about in the breeze and requiring tank tape

to hold it would be annoying. So some Racer's have lightened the original Steel doors as I'm doing and these of course

Fit nicely.

R

 

[924Srr27l]

Unless your car has a full cage, and really it needs to be a welded-in multi-point, those doors will be absolutely deadly in the event of a crash.

I'll try and not be facetious and pretend I'm not aware of the Risks ....[]

There's a Huge chunk of Fiberglass (Sunroof / Bonnet / Front Wings / Front & Rear bumpers) and Plastic (Side and rear hatch Windows) on the entire car that would also be "less forgiving" in an accident.

It's a Racer for the Road hence the RR in the codename...

I Just can't begin to consider adding 60kg+ with a Steel Cage when I've spent millions from a Lotto Grant to lose 250kg!

Hence why the rear cage/ brace bars are Aluminium and also why the Internal Door bar's I'm designing to be bolted inside each door will also be Aluminium..

Aluminium Struts / Stub axles and Rubber Top Mounts are still on the list..

R

 

[Eldavo]

The FG parts on the front end are less important than the steel bumper bars and chassis legs and structure that sit underneath them.

The doors don't benefit from being clad over a rigid structure hence the internal bracing and strength. A couple of bits of aluminium tube aren't going to save you from a side impact that you won't even hear due to driving around in your ear defenders.

I also love the the fact that your car has a "codename" - it is entirely befitting.

 

[944 man]

Gutted doors weigh no more than GRP doors, but only a fool would remove the side impact protection from the drivers door.

Not facetious Roger: conceited. And deluded.

 

[pauljmcnulty]

I can't believe that someone would compare plastic side windows or sunroof with door side impact protection! Perhaps leave the safety to Porsche and not mess with it, but then this could be Darwinism in action. []

 

[924Srr27l]

Gutted doors weigh no more than GRP doors, but only a fool would remove the side impact protection from the drivers door.

Not facetious Roger: conceited. And deluded.

I don't understand what your "Gutted" about?, these doors won't be lighter than Fibreglass ones?

These Steel doors I'm modifying with the side bar removed are stronger than any fibreglass doors.

The door bar on a 6 point bolt in Cage is quite low and doesn't look that helpful if a 4x4 rammed the

side of the door.



A weld in multi Steel would for sure be super safe but I'm not racing this car for now.



The 924 Carerra GT's Road (Clubsport) and Le Mans Race Cars used Aluminium for the Rollcage,

I can easily add some Aluminium structure / Door bars from the B Pillar down to the footwell...

The Road CGT Doors don' look like they have an Internal side Impact bar, and lastly the Outer Steel skin on the 924/944 doors

is only about 1.5mm thick (approx.).



There's plenty of Road Sportscars that are not as strong in the "What if" accident department.





R

 

[924Srr27l]

I can't believe that someone would compare plastic side windows or sunroof with door side impact protection! Perhaps leave the safety to Porsche and not mess with it, but then this could be Darwinism in action. []

Yes, I deviated from the "Perhaps leave the safety to Porsche and not mess with it" thoughts about 4 years ago on this project!

I have Messed with a nice Standard 924S in a Big way, there's no turning back now...

As for Darwin's Theory? " a theory that inherent dynamic forces allow only the fittest persons or organizations to prosper in a competitive environment"

So far so good..[]

R

 

[924Srr27l]

The FG parts on the front end are less important than the steel bumper bars and chassis legs and structure that sit underneath them.

The doors don't benefit from being clad over a rigid structure hence the internal bracing and strength. A couple of bits of aluminium tube aren't going to save you from a side impact that you won't even hear due to driving around in your ear defenders.

I also love the fact that your car has a "codename" - it is entirely befitting.

You mean you've never realised 924SRR27L means 924 S Road Racer 2.7 Lightweight!!

Must try harder.....

Tubes of Aluminium are not going to be as strong as Steel, Sure, but they'll be better than just the

Aluminium panel, and I was thinking of devising some more rigidity with extra tubing from the B Pillar to the floor etc...

Don't worry I've got it covered, Including my Ears ! []

R

 

[944Turbo]

some lightweight doors here but I think they didn't fit that well

https://www.porscheclubgb.com/forum/download.axd?file=0;641531

Are those GRP from Teilecar ? Club Autosport do them also and maybe they would fit reasonably

but they are of course made for Race use and "the Fit" is not a priority only the performance benefits...

Hence the fit is more important for my application as a Floppy door swinging about in the breeze and requiring tank tape

to hold it would be annoying. So some Racer's have lightened the original Steel doors as I'm doing and these of course

Fit nicely.

R

No, as it explains in the link (the blue here) they are carbon and from rsr-racing in the canary islands, however RSR may no longer exist as I cannot get the link in the other topic to work

 

[924Srr27l]

The link didn't work at Work, got it now that's the Aus Racer geezer....333 333

R

 

[Eldavo]

The "Aus Racer Geezer" knows a hell of a lot about these cars and you would do well to look at the evolution of his car. I don't recall him drilling holes in the spokes of his wheels - probably because he either knows what he's doing or surrounds himself with others that do.

Despite the fact we cannot see eye to eye on several things I dont want to think of anyone putting themselves at wholly unnecessary risk just to prove their point on the internet!!!

 

[924Srr27l]

The "Aus Racer Geezer" knows a hell of a lot about these cars and you would do well to look at the evolution of his car. I don't recall him drilling holes in the spokes of his wheels - probably because he either knows what he's doing or surrounds himself with others that do.

Despite the fact we cannot see eye to eye on several things I dont want to think of anyone putting themselves at wholly unnecessary risk just to prove their point on the internet!!!

Chill with your Health & Safety concerns, and thanks but no thanks on suggesting I look at other people and sources. I'm more than happy with the group

of Mechanical Race Engineers & Expertise I currently have at my disposal, who also as you put it "Know a Hell of a lot about these car's" and my holy Wheels are doing fine really...They may be coming off at some point for some Jap Rays 7x16 Ce28N Forged Rims...just over 6kg each!



R

 

[John Sims]

Doors are an integral part of the cars safety cell; used to transfer forces in the event of impact, not just as a barrier if T boned. The lack of protection in Lotus 7 type cars is the main reason I got rid of mine. They are great when racing cars of a similar specification but the internal squidgy elements are far too exposed and vulnerable when on the road or on a mixed track day.

Doors also add to the rigidity of the monocoque. Proper racing cars gain rigidity from properly designed multi point cages. The benefit of this gained rigity is so significant that some series actually dictate a maximum number of mounting points. So, without an appropriate cage, floppy doors could be detrimental to the cars handling.

Other than that, do what you like. It's your life. Aside for anyone foolhardy enough to sit in the passenger seat (best removed to save weight) the only squidgy likely to be killed is a Rodger.

With this whole "I might race it" thread, have you actually established what series you are aiming for as all tend to have rules on what you can and can't do in respect of modifications? There is no point in creating a race car which isn't eligible to race.

 

[John Sims]

I am pleased to hear you are changing your wheels as I had wondered if you had done a full stress simulation before grinding and drilling. I am assuming not.

 

[924Srr27l]

Doors are an integral part of the cars safety cell; used to transfer forces in the event of impact, not just as a barrier if T boned. The lack of protection in Lotus 7 type cars is the main reason I got rid of mine. They are great when racing cars of a similar specification but the internal squidgy elements are far too exposed and vulnerable when on the road or on a mixed track day.

Yes the 7's and many other fibre clad small kit cars are very vulnerable and this is always a risk on road or track..

Doors also add to the rigidity of the monocoque. Proper racing cars gain rigidity from properly designed multi point cages. The benefit of this gained rigity is so significant that some series actually dictate a maximum number of mounting points. So, without an appropriate cage, floppy doors could be detrimental to the cars handling. Sure, a multi point weld in cage would be so much stiffer than the current production roof structure. Quite how much the 2 hinges and one latch actually stop the body twisting & flexing and if this has a noticeable effect or not? [/i]is difficult to answer until its tested on the road. [/i]

Other than that, do what you like. It's your life. Aside for anyone foolhardy enough to sit in the passenger seat (best removed to save weight) the only squidgy likely to be killed is a Rodger. Yes the soft part inside any metal structure will always be the first to be affected!

With this whole "I might race it" thread, have you actually established what series you are aiming for as all tend to have rules on what you can and can't do in respect of modifications? There is no point in creating a race car which isn't eligible to race. There's plenty of options, CSCC Future classics, Welsh open series and the PCGB Speed championship etc..I've looked at and considered many but decided not for now as the car is in too good condition to make it a Race car and I also do not want to take it off the road this year but use it a lot. The CSCC regs are very open for example and this car would have a very distinct advantage compared to many others in it's class.

 

[924Srr27l]

I am pleased to hear you are changing your wheels as I had wondered if you had done a full stress simulation before grinding and drilling. I am assuming not.

I need to save up first they are £2000 a set ! and Ill also need to make bespoke Aluminium hubs 5x100 or 5x114 etc..

Yes the Bespoke Cup Wheels Full analysis was done by a Force India F1 Engineer and the design was machined accordingly..