1672 replies to this topic

[bullitA9X]

So craig your trans tunnel was fine at the start of your build but now its not??

[mshue]

Exactly what makes it no longer eligible?

[eyepeeler]

So craig your trans tunnel was fine at the start of your build but now its not??

The way I read the rules back then I believed I was ok. I had a bloke who is a long time IP runner look at it and his comment at time was that it should be ok, stretching it a bit, but should be ok.
I knew that I couldn't remake the tunnel in full as per rule 3.2 below, only minor reshaping is allowed.
Reshaping excludes the addition of new material as per rule 1.13.
Where I got to was rule 3.3 that allowed me to cut a larger hole for the Jerico linkages and shifter. The tunnel was not suitable to be "minor reshaped" as it did affect the integrity of the metal in the tunnel, it's 40 year old steel after all. Integrity has to be maintained as per rule 1.13.
What I did was remake to the best of my ability the tunnel for the gearbox as close to original dimension as I could, albeit with the cut outs allowed in rule 3.3.
The covering in rule 3.3 is part of the tunnel I made. The linkages are part of the gearshift mechanism and therefor original shape can be cut out.

1.13 MINOR RESHAPING: Reshaping of existing material. This excludes the addition, replacement or removal of material and must not result in a loss of integrity of the panel.

3.2 TRANSMISSION TUNNEL: Minor reshaping of the body is permitted to enable fitment of replacement gearboxes and clutch assemblies.

3.3 GEARSHIFT HOLE: It is permissible to cut or enlarge a hole in the floor, of the minimum necessary dimensions, for the gearshift and associated mechanism. At all times, there must be some form of covering around the gearshift to prevent the ingress of material into the cockpit.

What I didn't have was a spare chassis to rob a tunnel from and in the end, even if I did have one, it wouldn't turn out much different in my opinion once I had to cut out for linkages and shifter.

[eyepeeler]

Exactly what makes it no longer eligible?

the rules haven't changed, it's interpretation. I didn't have anyone come over and go through what I wanted to do.
I have had help from a few Torana lads,
Sam (Racehatch) and Paul Rule (PRule) have been great for info as they both race Hatchbacks in IP. I didn't talk to either of them before doing the tunnel, only a local IP racer over here.
I still believe I had to do what I did to fit a Jerico gearbox without affecting the integrity of the original tunnel. Thats open to interpretation.

[mshue]

That's a real bugger mate. Did you find it out going through log booking?

Oh well, at least there are a few other Classes you can participate in.

[Adam77]

Hey Craig just finished your thread, your workmanship is incredible just wandering have you driven the car or thought about going to a 4 speed and a standish tunnel?
Even with a 4 speed it will be a very quick car in ipra.

[Bigfella237]

I was just thinking about this beast the other day and wondering how things were going?

 

Wow, almost a year since the last post, now I feel even older!

[ozyozyozy]

Adam, the 4 speed geaboxes that can handle the power and abuse would still need tunnel mods for the shifters, the powers at be are againest the sort of mods required.

[eyepeeler]

I shelved the car after the tunnel problem. It's took me a while to get back into doing anything.
Long story short, the car will see its first track day for a test on August 30th.

[Bigfella237]

If you were in Victoria you could just put it on club rego and drive it around, it's no more illegal than thousands of other cars driving around down there!

[Racehatch]

I shelved the car after the tunnel problem. It's took me a while to get back into doing anything.
Long story short, the car will see its first track day for a test on August 30th.

 

Glad to hear you are getting it out for a run, hope it goes well and you get some enjoyment after all the heartache!

[Adam77]

Surely a Richmond Gear T10 with a dog box conversion (commodore cup) could handle power and toque with minimum mods to tunnel .Paul Rule in Victoria runs a front running ipra torana with a 4 speed.Craig can you please post a few pics or videos of the car out on the track,im sure everyone would love to see it going!

[ozyozyozy]

The decent shifters for the super t10's still require tunnel mods beyond what officials like.
This has been a very long hotly debated topic in IP.
Even if you slipped under the radar for a while, the moment you place in the top 5, they are like flys on shit to the car to get it canned for whatever reason.

First outing for a car i built this year we must of had about 4 officials go over the car top to bottom and half the field examine it, coz they saw it as a threat.
Car had been examined by the eligibilty officer weeks before it even turned a wheel.

[Adam77]

Hi Craig did you hit the track?

[AbsynthHatch]

Does the rules (officals) allow the use of the A9X blister that was used with the T10 in Group C or did this not provide the clearance neccessary for your box?

 

Surely even a mediocre 4sp shifter can be refined and 'tuned' to be made to work with some effectiveness, especially with your skills.

 

It seems such a shame that your initial dream was shattered because of an officals interpretation of a rule.

 

Can you not creatively massage an original tunnel or raise the floor and tunnel as 1 piece to provide clearance? Just throwing ideas around, though I'm sure you have looked at every possible solution.

 

Fantastic build and I'm sure you will enjoy the racing which ever category you enter.

[eyepeeler]

Hi Craig did you hit the track?

Not happy with oil pressure. At 5000 RPM it gets to 130psi.
Checked it with mechanical gauge.
Was aiming to have that sorted before going out but didn't happen.
Still trying to sort out why it is so high.
ARE are adamant that the gearing ratio is correct for that pump. So why is it so high.

[eyepeeler]

Does the rules (officals) allow the use of the A9X blister that was used with the T10 in Group C or did this not provide the clearance neccessary for your box?
 
Surely even a mediocre 4sp shifter can be refined and 'tuned' to be made to work with some effectiveness, especially with your skills.
 
It seems such a shame that your initial dream was shattered because of an officals interpretation of a rule.
 
Can you not creatively massage an original tunnel or raise the floor and tunnel as 1 piece to provide clearance? Just throwing ideas around, though I'm sure you have looked at every possible solution.
 
Fantastic build and I'm sure you will enjoy the racing which ever category you enter.

To be honest, I'm not sure what they would say. Group C rules don't relay into what's allowed for Improved Production.
A classic example is the hole in the bonnet for a car log booked as an A9X. They, as in IP, do not allow the hole as it is non ADR compliant as in the ADR rules of the day. Even though every A9X had the hole, with a patch supplied in the boot. The patch was not fitted by GMH or by Pattersons who had the contract to fit the A9X body kit for GMH, it was supplied to the selling dealer with hole in bonnet.

Yeah the initial dream of IP is not going to happen. But I will be happy enough just to do a few track days and enjoy learning the car.
Will worry about racing later on.

[Ice]

Gee thats sux Craig after all the work you have put into the car
track days should be fun though

[Racehatch]

Not happy with oil pressure. At 5000 RPM it gets to 130psi.
Checked it with mechanical gauge.
Was aiming to have that sorted before going out but didn't happen.
Still trying to sort out why it is so high.
ARE are adamant that the gearing ratio is correct for that pump. So why is it so high.

 

What is the oil pressure at idle speed? is there a pressure relief on the pump you can adjust?

[eyepeeler]

Hey Sam, Oil pressure is 80psi at idle and about 130psi at 5000 RPM.

Yes there is an adjustment screw at the rear of the pump, that is adjusted all the way out to its lowest setting.

I have a 28 tooth pulley on the F-Body crank harmonic balancer hub. The oil pump has a 40 tooth pulley. ARE are saying that the crank to pump pulley ratio is correct for that pump.

I have been told to cut a coil of the spring in the adjustment screw and test that. The longer term fix with be to fit a spring that has a softer spring rate.

I have been told that ideal oil pressure at idle is between 50-60psi.

 

ARE do not want me to increase the pump pulley to 45 tooth to slow it down and reduce pressure as that will also have the effect of reducing the scavenge effectiveness.

[Racehatch]

It seems a bit strange to me that even with the pressure relief all the way out its still so high, was it ARE that suggested the softer spring?

 

I'd try softer spring over cutting one, but I reckon you would be safe to go a tooth or 2 larger on the pump pulley and still be safely in the 50-65% range they claim it will work in?

 

Is this a fresh build engine? do you know what the bearing clearances are set to, as that will also have an effect on oil pressure.

 

Hey Sam, Oil pressure is 80psi at idle and about 130psi at 5000 RPM.

Yes there is an adjustment screw at the rear of the pump, that is adjusted all the way out to its lowest setting.

I have a 28 tooth pulley on the F-Body crank harmonic balancer hub. The oil pump has a 40 tooth pulley. ARE are saying that the crank to pump pulley ratio is correct for that pump.

I have been told to cut a coil of the spring in the adjustment screw and test that. The longer term fix with be to fit a spring that has a softer spring rate.

I have been told that ideal oil pressure at idle is between 50-60psi.

 

ARE do not want me to increase the pump pulley to 45 tooth to slow it down and reduce pressure as that will also have the effect of reducing the scavenge effectiveness.

[eyepeeler]

Yes, its a fresh build motor. ARE have said the same, that the clearances would boost pressure in an engine with tight tolerances.
Applied Automotive who have a good rep here in WA said the same as ARE, cut the spring to test it out, don't change the ratio.

ARE suggested a softer spring.

 

ARE are a bit mystified as to why its so high as well. They have built thousands of them and not seen it this high before.

[koalasprint]

If the oil viscosity is correct then it must be the pump/relief valve or a combination. If there was a restriction/blockage/super tight clearances then the pressure relief valve would still limit the pressure. Make sure you don't cause damage chasing the issue.