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hey Steve,

any issues with temps after the grout fill job?

Yo,

motor just got stripped down and reported on.....

Engine temps and water temps were fantastic whilst on track

max of ~90 degrees after each session (air guides/twin thermos air/breather tank were fabricated)

draw back.... concrete caused a hairline fracture upon setting (still tracked for 6 events after) :)

all parts in great condition, would reuse consumables if a street car but not taking any risks with new N1 block

:cheers:

Fire wall bars are cut that accuratly we can weld the tube back to the fire wall to seal it up, no cut plates required....

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And on the inside shit just got wild

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Hopefully finish off the front end of the cage tomorrow, few more bars to through to the strut towers and more chassis reinforcement to come.

First stage of this monster cage is now done.

Basicly there are plates welded to the area of the floor where the chassis rails are spot welded to the fire wall. The tubes running to those plates actually go through the plate and are welded to the inside of the actual chassis rail. The plate is then welded ontop to reinforce the rail to both the cage and the fire wall.

There is obviously tirangulation to those critical pick up points.

There is 3 bars running out to 3 points on the strut towers.

One horozontally out which will oppose the side intrusion. One out to the strut top and tower intersection which is X'ed inside the car and another from the base of the front leg to the side of the tower where the camber arms are bolted to.

The bar at the base of the front leg to the chassis rail bars is there for two reasons, one is to aid in a side impact, transfering the force to yet another strong point of the chassis and also to provide a triangulated support for the main rail support bar.

enough explaining, enjoy the first stage of what is probably the most comprehensive cage anyones ever put into a skyline.....

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Steve mentioned people were asking him how the car was going.

Update, the cage is nearing completion, hopefully tomorrow the hoop will have its diagonals and the front bases plated up.

Fab work left is some new jacking points under the car, pedal box frame and install, seat mounting and a new steering coloum.

Then a rewire before being sent off for paint

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Back to the top for this one,

Its getting a face lift

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When someone drops a car like this off at pro fabrication and says I dunno what I want just make it good the wheels start to turn.

Ive designed and FEA tessted the following cage and thats whats going into this R34

Front section to strut towers

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When you say 'FEA tested' what exactly have you done. I'm assuming a beam model of the cage minus chassis looking at torsional stiffness? How much optimisation is done (stiffness vs. weight) - I imagine there are diminishing returns when you start adding that much bar work.

Just cage modelling correct. We are mainly looking for ways to even out the load distribution and maximise torsional strength.

Weight vs ridgity is factored,

Obviously as you say there comes a point where the cage just becomes heavier without adding any strength. I questioned the small bars running from the base of the front leg to the chassis rail mounts. When removed we lost side impact resistance on the front leg. 1.1kg worth of bar that was worth while.

There wasn't much else that we tried which added any great benifit.

The only thing I'd like to have changed is the location of the X between strut towers. I think it should have been wider but engine restrictions prevented it.

The engineer we use to do these designs with us here always harps about intersection location. Problem is when you take the design to a car a lot of the time locations can't be exactly where they are desired.

I just seen your PM too ill send you a quote tomorrow.

Went in today for a seat fitting.... I have to say that the quality of the workmanship speaks for itself. To see it come together from scratch is truly amazing.

Motor duties have been appointed to PowerTune for a freshen up... N1 block now replacing the cracked concrete block. They were really impressed with the condition of the bottom end... Credit to the dry sump by PFRE and machine/assembly work carried out by Greg at Duncan and Foster.

  • 2 weeks later...

The rollcage is now completed and the body has been seam welded. Looks like a mess but once painted will be tidy.

The custom steering coloum is also finished.

We start with a shaped plate on the firewall and mount a spherical bearing and carrier to the plate.

Using 25x2.1mm 4130 tube the steering colum passes through the spherical into the engine bay.

I've machined up a basic 6061 series alluminium block to house the upper roller bearing in and support the end of the shaft.

More bar work from the bearing plate to the cage and bulk head support the coloum.

Modified sparco adaptor is welded into the shift and a roll pin is drilled and banged in for extra security.

This steering coloum is exactly how the V8 Supercar colums are done.

Pedal box mountings are underway but not completed yet, custom throttle pedal is also underway. We couldn't use a 3 pedal box due to the design of the cage. A custom pedal is being fabricated to clear the lower cage bars.

Fabricated pedal box mount completed. Reinforced with 1 inch 4130 tube back to the lower chassis rail support bars.

Decided today that the car is going to need some new jacking points under the car, the chassis rails have been squashed and the sils damaged from jacking the car up all the time at the track. Some specific jacking points coming from the cage will save the cars structure

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