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Gordo

Gordo takes over the Peter Mac Build.

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With race day (weekend) approaching fast, I gave the trailer the once over.

    7.15 am at the Phillip Island race track and it was about 6deg and foggy.  Rolled the car off the trailer and screwed the front splitter on. A few friends came over and did the walk around. The first time people had seen the car. It was nice to get a good reaction .  Scruteenering went well. I was in the second practice group. I have to say I was a little nerves. Lots of things could go wrong, but I had preperd well , but I will,still take it nice and slow and get my confidence with the zed. The first thing I noticed was how slippery the slick tires are on the first two laps. Also the brake performance was weard . They just didn't work. As hard as I pushed I couldn't get them to bight hard. I found myself braking way early and standing on the pedal as hard as I could. I actually came into Honda corner with no cars behind me and tried to lock up the wheels. Not even close. I couldn't do it all weekend , the brake pedal was as hard as a rock.

  But the aero was great. I could go faster through the fast corners once the tires warmed up than ever before.

The morning sessions track temp was below 10 deg. It wasn't till the afternoon when the sun came out and track temp went to 20 deg , that the tires worked a bit better.  My son timed me at 1.49s I was happy with that.

  But the brakes and tires would need some working out. Anyway, Sprint day was next.

 

      We were confronted with the same weather conditions. Very cold start.  I rolled onto the weight bridge at scrutineering. Was a little surprised at the weight, thought I might come in a bit lighter.  1020kg.

But when I thought about it it's got 40kg of roll cage, massive wheels, 15kg front splitter. Petrol tank cover and heavy brackets holding it up and electric powersteering .

 

  So the first session was cold and no tire temp. Temp gun on the tires was only 30 deg. So I temped the rear disc, only 40 deg and the front 60deg. Say what. Normally there off the scale. This wasnt helping  the tire temp.

Normally the brakes build heat into the wheels, and this transfers to the tires. NOT HAPPENING.

 

Over all the car was good. Spring rates worked. No vibrations , turn in was good, understeer , over steer was natural . But did notice the R32  Diff wasn't working, was single spinning over Lukey Hights.

Ended up with a  high 1.48s.  Happy to get through the weekend .

 

  The pedal box is having the master cylinders changed for more pad pressure. So I'm hoping that will fix the brakes, and with any luck help the tire temps. The diff I'm going to leave for another time.

 

The zed has hit the track, so the fun has just begun.  It's race ready. But it will never be FINISHED!!

        Hope you enjoyed the journey . I will be back on the track in about 4 weeks.  Cheers.

 

  Some pics from the weekend.

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Gordo

 

Been following your progress for a few days, have to say spectacular!

 

Great to see Pete's legacy in such great hands and equally the work you have put into it and your achievements.

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This car went to exactly the right person!

Have no doubt you'll have the issues sorted and breaking records soon enough. And it looks amazeballs!

But I must say........... 15kg splitter? ???

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Looks great on the track Gordo. So once you get the brakes sorted and the diff, what sort of times around P.I do you wish to achieve? i know there are other factors that come in to play, temp, track temp, slicks or semi's.

 

John

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Hi John. Having had the car on the track only once. There are a few things to get sorted. It's a never ending search for the perfect set up. And sometimes you don't even know if you've got it or not. Time will tell.

  But I would expect there could be another 2 or 3 seconds buy the end of the year.  It just depends how well I can read the cars setup. You know , finding the sweet spot.  When are you coming out for a play?

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Time to send the car to weightwatchers ;D ;D

 

Mine was 960kg ready to roll on the track without me in it, and all steel panels bar the bonnet. Was stripped interior, but standard dash, standard wiring harness, but perspex windows with glass screen, full welded and steel cage also R180 diff, basically just as strong and 15kg lighter than a R200.

 

If I was serious, I could have found another 15kg or so to get out of mine, but I reckon that would be the limit for a door to door racer to keep it legal for 2B and also safe.

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Great job Gordon. Have to be happy with that first time out !

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Needs a Jenny Craig!

There's a couple of Group S Z's getting around, today, at 960 and 980 kg, couple more slightly heavier, and they all look very stock ext and int!

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Thanks for your advice guys. Do you know how many seconds 40kg adds to a lap at PI ?

 

Good point :)

 

Its a momentum circuit - right...? ;)

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Weight is not everything and if there is a more than compensating benefit then that's good eg like aero devices. Then there is chassis rigidity, a little bit of extra weight in the right places can again be worth it. Where do you reckon your extra weight is Gordo?

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Hi Richard, as I said above , it's got a little fat in it.

 

(But when I thought about it it's got 40kg of roll cage, massive wheels, 15kg front splitter. Petrol tank cover and heavy brackets holding it up and electric powersteering .)

 

      With my other zed , I keep adding to that and it keep getting faster.

  Electric powersteering .

  Bigger wheels and rubber. Added weight, but gave over three seconds.

  Front splitter added wait, but cut over a second.

  Heavier coil overs ( bigger wire). Handled better.

  Triple webers, are heavier than twin SUs. Bit more power, bit more speed.

  Fancy headers are heavier, but more power. 3" exhaust heavier.

  And yes bigger rotors and six piston callipers are heavier, and to be Honest they slow me down a lot .

 

  But all jokes aside, it is what it is.

All that stuff I mentioned above would not be on a true Historic car. And that's why they are Lighter!

   

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Just to weigh in on this matter (boom boom) ;D

 

My car is 1200kg at the PI scales race ready, which is more than I had hoped, but it is what it is.

 

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Great thread, I love it when someone pushes to the limit.

 

And yes 195/60/14 wheels and tyres will be a lot lighter but won't do PI in the mid 40s.

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Interesting comment about your big front brakes Gordo.  Mine has a big (heavy) front brake kit too and I reckon it's more of a hindrance than an advantage, particularly considering it's unsprung weight. PI is not demanding on brakes as well.

 

Interesting that two 'heavy' Zeds easily do the fastest lap times at PI too  ;D

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Interesting that two 'heavy' Zeds easily do the fastest lap times at PI too  ;D

What you're saying Rich, is there's hope for the ZX's yet.  :P

I think there's a fair bit of steerer being the key here!

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Be interesting to see what the final version of my 280ZX shorty weighs, I'm guessing under 1200kg with the heavy steel doors replaced with f'glass ones but with a heavy lump auto transmission.

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The weight of the car depends a lot on preparation and what the car is built for.

 

Mine at 960kg had a single skin fibreglass bonnet, and all other panels steel, the front guards were lighter than 'glass, but still steel, couldn't push on then to move the car or lean on them. Windscreen was glass, but the rest of the windows 3mm lexcen, with aal the standard mechanisms removed from the door, and the rear hatch 1.8mm lexcen. All rubbers were removed from the body, also spent a weekend under the car removing all sound deadeneing material inside and out. Interior was stripped, except for dash and the right rear trim to cover the fuel filler pipe to the standard tank. Ran standard gauges and dash and wiring harness.

 

Car ran a full steel welded cage and also seam welding in the front. Also used heavy Simmons wheels, 18x8" with240/640/18 slick tyres, L28 with standard type log manifold and Haltech computer. The car ran standard lights that worked and full grill, as per the rules. Weight saving was made by not having handbrake or cables and ratchet, also removed all heating system, just had ducting from the vent inlets to the base of the windscreen for airflow on the move and also removed the windscreen washer bag and fittings.

 

Car still used standard battery in the standard location under the bonnet.

 

Suspension was standard type struts and arms, though modified a little, spring seats dropped, running much heavier springs than others, and slightly tweaked in the rear, but basically built heavy to not be moved by the rigors of track racing.

 

Passenger seat was removed, though when required by the rules to runa CAMS approved seat, we ran a kart seat tek screwed to the floor. Drivers seat was a fibreglass race seat.

 

Brakes were 4 spot Willwood dynalites up front with TP Magna rotors and Volvo 2 spot rears with a solid rotor, so a little weight saving there.

 

I could have gotten more weight out of the car by doing the following:

Fibreglass hatch

rewire the car for the bare minimum needed to run the engine and ancilleries

Run the smallest battery possible and use booster to start the car

Some drilling of sills, etc with a hole saw to reduce weight, remove all the stainless steel trim from the windows that were used to hold windows in.

Attacking the doors to cut out as much as possible including removing the standard door latch mechanisms to save some weight.

 

I think I could have gotten the car down under 940kg but that would have been the limit to be safe and still comply.

 

My times, last time around lakeside, into the 61's on a 45 degree day on tyres with the canvass hanging out of the tread, last time at EC on the old configuration, 1:48's, so would expect to do 1:46's on the new track with the turn at 7 basically no more and 9 opened right up.

 

Basically, there will be plenty of weight that can still come out of the car cheap and easily without affecting the performance. To do the job right, you need to start from scratch like I have with the S14 and baegan with a bare shell. That car should be ready to race at around 1050-1100kg from a standard road car weight of 1250kg, with a very comprehensive cage welded in.

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You've done very well to get down below 1000 kg. When Peter started this project he has done everything right. Every thing that opens and shuts is fiberglass and the front gards. I'm told the front gards with the flares aren't much lighter. So for me finishing the car I have added what I needed to go as fast as I can with my L28. And of cause I tried to go as light as practical . The front splitter is 1800mm wide and 700mm deep, cost me $50 .  I'm not getting something made up for $500 to find out its not working properly.  My point is now its complete I have the opportunity to trim the car down as the development takes place.

    Sinisha's car has Awsome power to weight, his aero add ons have properly given him 4 to 5 seconds at the island. That's a weight gain well worth doing.

    To be honest , my zed is under powered. It really needs 500 to 600hp to make the slicks and aero work at its best.

I can feel the car running out of power at the end of the straight. It's down 200 to 300rpm. But faster mid corner speed.  It's all one big trade off.  It's like what do you want out of your car!

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Stripping weight out of a car is not rocket science and as for the Nissan S chassis it has all been done before many times. Besides the aftermarket for the S is one of the most comprehensive around. But what Gordo is doing, and Sinisha has done, is something else again so obviously there has to be a development stage before the final version, if development ever stops of course  :)

 

I just think it's great that there are two S30's which are doing exceptional lap times at the fastest permanent track in AU. And are doing so as a direct result of their own development work.

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But did notice the R32  Diff wasn't working, was single spinning over Lukey Hights.

 

Is the diff from a GTS-T or a GTR?  If it is a viscous diff from a GTS-T then they generally seem to overheat and stop working on the track.  A clutch pack one from a GTR would be a good upgrade.

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Hey Richard. I love how your thinking .

      (But what Gordo is doing, and Sinisha has done, is something else again so obviously there has to be a development stage before the final version, if development ever stops of course  ).    It never does.

        When are you going to come and join us in your new  V8 280zx.

 

    Hi Scando. Not sure which type of diff it is. Even when I was in the drive way. ( cold diff ) its a single spinner.

I will get it sorted when time permits. Got lots of stuff to work through.  haha.

    Thanks for all your feedback guys.  Cheers.

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Awesome car Gordo, great job, absolutely love it!!! And 48's outa the bag gotto be happy with that. My prediction is there may be a few more than 2 to 3 seconds there to be had at the Island. Only question I have is how long will you resist the temptation to whack a turbo on that bad boy?

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My prediction is there may be a few more than 2 to 3 seconds there to be had at the Island.

 

I'll second that.  I'm calling low 1:4X's by the end of the year  ;)

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Thanks for your confidence in me Boys. I'm not really a turbo guy. I like doing as much as I can buy myself ,turbos and computers are way beyond me.. I like the idea of the L28 and webers. So I measure my performances on cars with similar set ups.    As for lap times, the lower the better. I guess everytime I go out I'm always trying to do a PB, aren't we all !    Cheers.

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