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Also, insufficient lubrication of the top end at low rpm is far less of a concern for me compared with the bottom end and high rpm (also much cheaper and easier to fix).

x2

The top end also needs bugger all oil compared to the bottom end. Just don't touch the VCT gallery and your all good

I'm hitting the limiter in 3rd about half way up the hill now which is a little annoying, I don't really want to pull 4th either because it just bogs down and doesn't go much faster, I suppose not much faster is better than no faster in 3rd though... WTB Hollenger 6 speed anyone want to donate one?

A higher diff ratio might be worth a try.

When we had the diff ratio in my car spot on it was just about on the limiter in 4th on the start/finish straight. Back to 3rd for the esses until about 1/3 of the way up the hill then into 4th right over the top of the hill until the hump in the main straight where I'd pick 5th. Back to 3rd at the end of the straight and then short shift into 4th for the sweeper onto the start/finish straight. My engine was more torque than revs though so it may not work for you but it's worth a try.

Only bugger is it means changing diffs between Baskerville and Symmons but that's not a huge job and it's a good chance to check your tail shaft and drive shafts between rounds.

Symmons is a different kettle of fish, there's no real way you can get around doing lots of gear changes there.

I'd be a little concerned about your N1 pump too.... I had one in my 25 bottom end and it was starting to crack allready- no collar, but the pump had done less than 2k km's.

I'd rather take every other precaution to keep the oil where it needs to be, let the crank case pressure out and only fitt restricers at a last resort.

I see where youre coming from Jman, but id put them in as not many people really want to have to pull a head or engine out more than required!

sump has to come out to be modded, so id pull the head, fit restrictors, get a decent sump with gates, fittings for your breathers.. dont do the head mod...i can name quite a few big names that do not fit it.

get a decent breathing setup with decent catch can.. done...

if you really want a safe engine, upgrade the oil pump.

but id just wait till it pops, then rebuild time!! :D

Edited by jangles

Just some aero stuff I wanted to save for later so I thought I'd put it in here

***All this data was found through many hours of research and is used in race applications. So if you think it is false, then go suck a big one. It has been windtunnel tested and analyzed through computers so it obviously works. If you have nothing positive to say about this then don't read it, because I can say you won't find this information anywhere.***

The information below is regarding a VZ Commodore V8 Supercar.

The basic understanding of aerodynamics for a racing car is an aircraft wing turned upside down producing down force instead of lift. Down force is mainly created at the front and rear areas of the car through the use of aerofoil's for improved grip and high speed stability.

The governing body TEGA (Touring Cars Entrant Group) strictly controls the aerodynamic work on the make of vehicle. The rules enforced ensure the aerodynamic profile of each competing car is similar to its rivals.

In the Figure below, it shows how the incoming air is split by the stagnation point into slower and faster moving air. Due to the chamber and shape of the airfoil, the air on the lower surface moves at a higher velocity than the air on the top. The pressure on the top surface is higher than the bottom surface and produces a "suction" or net downward force on the airfoil.

2008715213146_Wing%20Cross%20section.JPG

Using Computational Fluid Dynamics and following within the rules of adjusting the AOA on the airfoil. It was found the airfoil on a Holden VZ race vehicle produced a linear shaped down force between the angles of 0-15 degrees. However, as the AOA increased to the maximum permitted 20 degrees, the airfoil began to stall, resulting in a drop of CL. This therefore means the airfoil is not working as efficiently as it is intended, and a subsequent amount of drag is being produced with little increase in down force.

2008715213818_Airfoil.JPG

Further analysis on the rear section of the car, especially the rear wing with a Gurney flap placed at the trailing edge, with another Gurney flap on top of the boot . This found that with the addition of the Gurney flap placed on the boot prevented the stalling of the airfoil on the rear wing, especially at 20 degrees AOA. This in turn demonstrated the boot Gurney flap is acting as a guide vane for the air, which deflects it upwards over the boot and attaching itself over the low pressure region of the rear wing.

2008715214038_Flap.JPG

Another addition to downforce is also due to the shape of the car. Which its shape produced much greater downforce than the rear wing.2008715214327_Table.JPG

Diffusers on the vehicle. Before analysis the Angle Of Attack on the diffuser was 26 degrees.This ineffectively stalled the diffuser causing much unwanted drag. Through CFD analysis and wind tunnel testing, the diffuser on this particular vehicle began to stall at an AOA of 15 degrees. As the AOA decreased subsequently down force increased.

2008715214910_Diffuser.JPG

Moving on to the frontal section of the motor car, the front splitter or front spoiler. The purpose of the splitter is to direct air over the top and under the car. The splitter works in ground effect, and produces a large amount of down force for the frontal section of the car. Under usual circumstances, the front wing operates in an undistributed freestream air. Since the proximity of the wing is so close to the ground, ground effect has a major function in the motor industry and it is usually related to the ride height of the vehicle. Lowering the frontal section of the car does not dramatically increase down force. Instead lowering the car beyond a certain dimensional height produces an upward lifting force on the vehicle. The optimal ride height is between 100 millimeters to 110 millimeters. The car ceasing to produce down force at a ride height of approximately 85mm, and begins to generate positive lift. Due to an increase in lift in relation to ride height, air is no longer forced to accelerate under the car creating a low pressure region.

As the ride height decreases, a pressure gradient is created at the front of the vehicle. However this pressure gradient restricts the flow of air to under the car. This means the air is 'choked' and the Venturi effect created by the under-tray and the ground is reduced. This in turn affects the handling and driving dynamics of the car. The down force is reduced as the pressure is increased, which makes the car feel light at high speeds and not be responsive in relation to driver input.

If your brane isn't herting by now, then you're a grater man than eye.

Edited by zoidbergmerc
  • 3 weeks later...

I was bored while I was waiting for the oil to drain so I put the indicators where the parkers should be so I've actually got indicators on the front. Swapping them over was easier than sitting down, there is little plugs that go into both the indicators and the parker plugs that are the same so I just swapped them over and got some little orange lights to go in there from repco.

_1019651Medium.jpg

Looks goooooood. Well I like it :)

Then I took the Lenses out of the old indicators, hardest job in the whole world it's like stuck in there with glue or something! and put them back in the guard.

Then I had two LED work lights that I thought I could use but I wired them up and they promptly caught fire. Apparently they can't handle twice the voltage they're supposed to have even though it clearly said 'Heavy Duty' on the box.

Here is what it looked like before they broke :(

_1019650Medium.jpg

And an obligatory turbo picture :)

_1019658Medium.jpg

ahhhh, the reason I get up and go to work every day :)

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