Just started project to create Group S car

Glenn Campbell · March 25, 2009, 08:17:58 PM

I have just purchased a 1979 GTV, some work done on engine and lots of work done on body, ready to turn into a Group S racer. Any help with advice would be great. eg who would you recommend for an acredited roll cage? I also have a glass (after market ) roof. Should I replace it with lexan?

Jekyll and Hyde · March 25, 2009, 09:05:12 PM

Quotewho would you recommend for an acredited roll cage? I also have a glass (after market ) roof. Should I replace it with lexan?

For the roll cage, Mark at Eastern Race Fabrication in Bayswater. Phone: 0419 696 660

For the roof, take all the sunroof gear out, and get metal welded in the hole, or if you can find a whole roof transplant that. Sunroofs make the body flex more.

alfagtv58 · March 26, 2009, 09:11:52 AM

Great stuff Glenn. When do you anticipate having it finished?

Quote from: Jekyll and Hyde on March 25, 2009, 09:05:12 PM
Sunroofs make the body flex more.

and are quite heavy, which raises the centre of gravity.

I assume that you know Ojars is where to get the lexan, given you also run a 944 race car!! I have left my original glass with him for a template, but be careful with the rear screen, I left the 'glue in' type there and you want to get the rubber seal type which is smaller.

Cheers,

Glenn Campbell · March 29, 2009, 02:35:44 PM

Thanks guys for the advice - I anticipate having it ready for the second half of the year. Any other advice re Brake pads, suspension mods (those allowed), transaxle mods (those allowed) would be appreciated.

alfagtv58 · March 30, 2009, 10:58:13 AM

Brakes - I run EBC reds ATM. I have also ditched the booster and installed a pedal box (pedal box fabricated by Eastern Race Fab and fitted by Hugh at Monza motors) with master cyls sized by Howard at Race Brakes.

Suspension - Short story - Koni Yellows re-valved (see Hugh at Monza for spec's), Vin Sharps monster torsion bars, bigger front sway bar, muuuch heavier rear springs (I am running 240 lbs), rear deDion modified with a couple of degrees of camber. Best to chat with Vin Sharp for full run down.

Transaxle - 75 Twin Spark with modified ratios. This unit runs the same housing as the standard Alfetta, so it is all above board. Again, chat to Vin Sharp for spec's and $$. Which reminds me, I must get that 5th gear mod done......

k76 · March 30, 2009, 01:39:15 PM

Just to satisfy my curiosity, what is the advantage of ditching the booster? Better feel or lower weight? The shaft running across the firewall is a heavy beast!

alfagtv58 · March 30, 2009, 02:09:35 PM

It isn't for a better feel, that's for sure. My pedal feels quite 'wooden'. But getting rid of the booster and that steel telephone pole that runs across the firewall saves a bunch of weight. It also allows for a balance bar to be put in so you can get the brakes set up right. Keeping in mind, GroupS regs do allow for dual or tandem systems to be fitted and also allow for an adjustable bias but it is not allowed to be adjustable from the cockpit.

k76 · March 30, 2009, 04:26:49 PM

Thanks Phil,

Can't you adjust the bias with the normal setup? I know the standard item valve isn't adjustable, but I thought it was a matter of getting one that is?

Kris

Colin Byrne · March 30, 2009, 07:18:59 PM

Quoteit isn't for a better feel, that's for sure.

That said you should get a more 'consistent' feel without a booster as levels of vacuum will vary, depending on throttle position, which will change the amount of power assist given by the booster, eliminating the booster removes that variable

QuoteCan't you adjust the bias with the normal setup? I know the standard item valve isn't adjustable, but I thought it was a matter of getting one that is?

While you can get adjustable bias valves which are easy to install, a balance bar is a much better option. The problem with valves is they effectively throttle the brake line, while this works fine on a brake apply you can have problems on brake release as the fluid is throttled in both directions which, in some cases, can cause the rear brakes to stay engaged after the brake pedal has been released.

alfagtv58 · March 31, 2009, 08:41:29 AM

Quote from: Colin Byrne on March 30, 2009, 07:18:59 PM
Quoteit isn't for a better feel, that's for sure.

That said you should get a more 'consistent' feel without a booster

Yup, at the 6 hour (in '07) I did a one hour long stint and the pedal felt the same after an hour of pounding! At Bathurst (really hard on brakes) at the end of the weekend the pedal felt a bit spongy after the chase, but I think if I bled the brakes on Saturday night it would have eliminated that.

Scott Farquharson · April 07, 2009, 11:52:38 AM

Great stuff Glenn - Good Luck with the project!

Glenn Campbell · April 12, 2009, 10:41:55 AM

I am gatting a 6 point roll cage and race seat fitted at present and replacing the fuel tank with a 40 litre plastic safety tank - are there any issues with placing this in the rear of the cabin - I know that I will have to seal this from the cabin somehow - any suggestions?

Also - oil catch tanks - any sources?

This car may be ready faster than I expected, so....

Paint Color - I suspect Monza Red is over done - any sugestions of a color ( and speed stripe color?) not in use by any of the group S guys would be helpful. The original color of this vehicle was dull ruby red - awful.

Glenn Campbell · April 20, 2009, 06:01:25 PM

The roll cage is now complete, race seat fitted, safety fuel tank fitted... only a trifling few (pages) of mechanical issues, suspension mods and paint job to go!!

I need urgent advice on 3 issues - are there any restrictions on cold air intake systems - can I use trumpets? Can I brace the brake booster? Where do I source extractors?

alfagtv58 · April 21, 2009, 09:39:17 AM

Quote from: Glenn Campbell on April 12, 2009, 10:41:55 AM
Also - oil catch tanks - any sources?

I had mine fabricated up by Mark at Eastern Racing Fabrications --- 0419 696 660

Quote from: Glenn Campbell on April 12, 2009, 10:41:55 AM
Paint Color - I suspect Monza Red is over done - any sugestions of a color ( and speed stripe color?) not in use by any of the group S guys would be helpful. The original color of this vehicle was dull ruby red - awful.

The Alfa's at the Easter race meeting had every colour under the rainbow!! Having said that only 2 red Alfettas and 2 or 3 red 105's. Fair bit of Silver on the Alfetta's though.

Quote from: Glenn Campbell on April 20, 2009, 06:01:25 PM
I need urgent advice on 3 issues - are there any restrictions on cold air intake systems - can I use trumpets? Can I brace the brake booster? Where do I source extractors?

1. no restrictions on air intake, trumpets are fine.
2. I have removed my booster, so bracing it shouldnt be an issue!
3. Vin Sharp at PACE Eng. 9844 0147

Glenn Campbell · April 22, 2009, 06:04:49 PM

Thanks Phil

It's hard to go past Red. I will make up my mind soon.

Thanks for the advice - We are a few weeks away from having it mechanically put together, and then it's only the paint job and plexan to finish.

The worst part will be painting the roll cage - you have to be built like a jockey who does Yoga - and I am built more like a Bear!

I will try to post a photo soon.

Regards