90 replies to this topic

[A9X]

Here we go again, Targa West is 3 weeks away and time for a quick update.

We had the car on the track yesterday for a shakedown and cobweb removal session. Thanks to Dave and Alex for a helping hand. Main task was to get some front end suspension info, confirm some rear end changes and check the vibration issue was cured.



By all accounts, people liked the sound of it all. (ask dave and alex)

We planned to be running the new Jongbloeds , but they didn't show up in time so we had to run with my 15 x 10 Hotwires and some 255 Yokohamas.
Short story, no traction.



Otherwise, minor carby issues still, we spent the day doing sponsor rides and basically making minor changes. Couldn't get enough grip out of the yokies to put any decent forces through the front.

Now that the new wheels have arrived, we will get some r spec rubber on them and do it all over again.



Welby

Edited by A9X, 08 August 2008 - 09:23 PM.

[A9X]

5- 7 September, fathers day weekend.

Hope to see you there.

Welby

[Tiny]

WOO HOO mate!

Enjoy yourselves That's the main aim

[A9X]

Thanks big fella.

We are all keen.

Welby

[A9X]

So, as an update from the last thread (07)

We have made a number of minor changes over the last 6 months, mainly from the early shot on day 1 of the car downhill through a medium left hander.



We were very concerned with the left rear wheel stuck up in the air and the front right buried up in the guard.

Pics of the car at Bathurst didn't show any similar attitude to the car and the times were fine. Tyre wear fom Bathurst was excellent too.

So we swapped out the edelbrock adjustable rear arms and replaced them with bog stock standard UC top arms. Even left the rubber in.
Next change was to back off the rear sway bar to take some load off the front end.

We have pulled the front adjustable sway bar off, replaced the engine bay side skirts and constructed a small undertray.
A rear mount whiteline bar is currently under trial, but mounted quite low. Also we are having some custom made springs delivered this week. Still staying with the light poundage we have raised the height of the front of the car and change the rate of the springs.

A trip to the wheel aligners found the chassis mount point under the drivers feet was moving a little. We shaved the mounting tube a bit and have sorted that. Nothing else looked amiss.

Two small cracks were found in the lower mount plates on the diff for the lower arms, these were tig welded.

The brake pads were inspected when we pulled the front springs out, to find the passenger side was cracked from heat stress, the drivers side actually crumbling when we pulled them out. They were Pagids. I have replaced them with Bendix Ultimates for a try, but am up for other suggstions. (might start a thread).

A quick run at Barbagallo last week showed no change in feel to the brakes, but did seem to suffer from pad knock off more than i remembered.

The gearbox has been raised at the rear as far as possible to help with a vibration at high speed. Managed 180 Kph frequently approaching the final corner, with no detected vibration, so i guess we have got on top of that one.

Not a lot of useful info was achieved at the track, due mainly to the wheels not turning up in time for me to mount the race rubber. We ran on 255 Yokies, which were just not up to the task.

Finally, we have not sorted the Rochester yet.

Welby

[A9X]

Hi Tony.

Those bedford springs are really good for the circuit boys, they come in at around 1100lbs though. This is too stiff (IMO) for our bumpy back road goat tracks that we race on here.
I've got 800 's in at the moment and they are 1 inch lowered. We are going back to standard height with a change to the spring construction.

Yes we believed pinion angle was out, all things pointed to the gearbox needing to be raised.


Thanks for the luck, we'll take it.

Welby

[Racehatch]

The springs is a tough one, I started at 1200lbs, but when I did the 3 link rear end (similar idea to what Hatchy's mate is running). Had to stiffen up the rear, and soften the front to around 800lbs, also with the change to A048R took a fair bit of neg out as well.

Totally transformed the car, much better under power mid corner and exit which really helped the exit corner speed, didnt have enough track time (with that setup) to really get it right, but I know how I'll be building the next one.....

[A9X]

Thanks Rory, wher do i get those pads, wouldn't mind a comparison.

Welby

[A9X]

Well i'm glad you asked.
Initial scrutineering today.


Swapped springs for some custom Quadrant springs. Chasing a raised ride height and increased spring rate.

Fail,
Dropped the car onto the front tyres. Don't know how they got that so wrong.
Dealer & i went over the measurements we sent and our numbers look good, so it's they're end.
Funny thing, when i unwrapped the springs , i noted they were only 5 coils and mentioned 'hope these work, don't look like they would hold up your ****.'

I have Dave's new King springs 1000 odd pounders here that we were using for a static comparison. They are shorter than my original Quadrants and also they are thinner in steel diameter.
So with an hour left before our booked slot, we swapped the second set of springs for the day, this time installing Daves for comparison.

End result, we couldn't run the Jongbloeds, they sit 30 mm out further than the Simmons and itr was just enough to foul the guard.

See here.



So we bolted the Simmons on and headed off to scrutineering.

Did take the car for a quick drive in the local area afterwards though. On smooth roads it was fine.
Just have to get the ride height up and sort out the wheel offsets at the front.

So it's back to the drawing board on monday.

And i must get Dave's springs back to him

Welby

[enderwigginau]

How close to the factory undertray is the one you have built?
Have you put a cut-out in to suck air from the engine bay and create a vortex to suck the car down?

Hatchblack has a factory one, and I have two copies we made in light gal.

Grant..

[A9X]

How close to the factory undertray is the one you have built?
Have you put a cut-out in to suck air from the engine bay and create a vortex to suck the car down?

Hatchblack has a factory one, and I have two copies we made in light gal.

Grant..

Hi Grant, last time i saw a genuine undertray was 20 years ago.

We have a light alloy one that runs from the front corners of the spoiler (sitting up in the inside lip of the spoiler), under the brake ducts, back to the crossmember.
we have an exit for heat but the Barons comments a couple of posts up have me concerned.
Ours definately is on an angle from the spoiler down to the crossmember and i can't see how i could make it the other way. The crossmember is definately lower than the leading edge of the spoiler.

I'd love to see some pics of yours and i will post pics of mine shortly.

Rory
Sorry no chinamen or mirrors, just a good dose of motorsport mayhem.
I'm guilty of trying to improve on methods used in the seventies, and also focus the car on the rough targa special stages, not a smooth race circuit.
However, sometimes i'm trying to reinvent the wheel.(pardon the pun)

Craig measured the car himself and i'll leave him to review his figures and suggest where i'm at. I'm not convinced the wheels are totally wrong, especially as i'm comparing them to the simmons which we all know are custom made to suit the brakes, not the car's track or design. I think if the ride height was correct, we wouldn't be half way stuffed.

I have standard insulators already, which is another point..
May need your contact for those bedford springs.

Here is a photo of the 850 lb springs(old) and the replacement 900's.




You can see they are shorter even before we fit them.

Welby

[LXCHEV]

Great thread, very interesting stuff. Best of luck with it all Welby.

Keep the blog entries coming along!

[enderwigginau]

The factory tray bolts to the lower radiator support, the side splash guards and extends back to the crossmember.
It has a kick-out halfway back that is about 30deg down (?) and spans about 40% of the width of the tray.
As far as I know, it is level across the car.

Being up under the radiator, this would put it behind the spoiler already.
Three function I can see -
Channel all air through the radiator,
Move engine bay air rearward out of the bay, and
Stabilise airflow under the car.

Maybe Hatchblack can get a picture for us of an original on the car.

Grant..