584 replies to this topic

[RX25SE]

Do you have a tech advisor that you can call on to clarify rules, or check on the build to make sure it will pass tech inspection?

[JDWhiteWRX]

Do you have a tech advisor that you can call on to clarify rules, or check on the build to make sure it will pass tech inspection?

It's just a guy I can email with questions.

[JDWhiteWRX]

I've been in lockdown the past few weeks and it probably won't end any time soon. Luckily this has given me plenty of extra time working on the car.

 

Most of the work has been around getting all the front end panels mounted onto the car. I bought some 16mm x 1.2mm 4130 chromoly tube and a very cheap manual bender from ebay. The bender snapped during the first bend but I was able to modify it to mount in my vice and now it works surprisingly well.

 

The tube structure I'm building is very light and will be removable by taking out several bolts. First step was to make a rear mount on the chassis.

 

 

This is how all that turned out, one on each side.

 

 

Then it was just a matter of bending some tube and making some tabs to hold the fenders in place.

 

 

The whole thing is rather basic but it is surprisingly sturdy.

 

 

This is it after finishing both fender mounts. More tube which I have already bent up will continue around the front and attach to the top of the bumper. I have left that bit off for now and started work on the main reinforcements to the front chassis rails.

 

[RX25SE]

Its really starting to look like a car again.
Nice work!

[allpaw4]

Wow. That looks shit hot. How much travel do the wheels have before they hit the guards and or the support structure? Photos make it look really small, but I'm guessing there's around 40 to 50mm?

[JDWhiteWRX]

The car will only have 75mm total wheel travel so there is plenty of clearance.

[El_Freddo]

The car will only have 75mm total wheel travel so there is plenty of clearance.

Geez and I thought my L series has small wheel travel!

Looking mint. I bet you’re stoked with how it’s looking. I love your rod structure to mount the panels from - very neat trick! Will there be any sort of wheel well/liner or not having the to reduce weight? Also a thought that the rotational turbulence from the wheels could mess with the engine bay air pressure system for cooling.

Cheers

Bennie

[JDWhiteWRX]

To be honest I'm kind of making a lot of this up as I go    

 

Part of me says make a kevlar liner (tubs) and another part says just add big vents above the wheel supergt style, would probably help pull some heat from the engine bay too, but is the drag penalty too much?

 

Not sure really at this stage, I'll cross that bridge when I come to it.

[El_Freddo]

Hmmm... I’ve always thought the wheel rotation creates an air flow at the top of the wheel in the direction of travel, as choppy as it maybe. I think this is why car manufacturers tend to put little downward flaps in front of wheels to help direct air in the direction of tyre travel - which helps the tyre not fight against incoming air - something I look at with many 4wds and their half or more exposed front wheel, can’t be good at highways speeds!

Also thinking about when it’s raining and you’re passing vehicles, the wheel spray seems to be thrown out forwards before being caught by the passing air and thrown out backwards. This makes me think that air in the wheel guard follows the direction of the wheel. Not having a cover over the wheel to separate the engine bay from the wheel guard could equal issues with the low pressure system behind the radiator to draw air through it.

But I’m no engineer, just sharing my thoughts about my observations. You might have access to better research on the topic. And side note, I wouldn’t go with the wheel vents, keep the lines clean Your race car though!

Cheers

Bennie

[JDWhiteWRX]

The radiator and intercooler will be fully ducted, air comes in the front bumper and exits the bonnet so it will be independent of the engine bay.

 

The car will have a full flat floor so the engine bay will be sealed underneath too.

 

This is why I thought it may be a good idea to leave the engine bay open around the wheels with vents above and behind the wheels so air is drawn out from the engine bay sideways. This may not work though as the air pressure in the wheel wells may be too high, more research is needed....

[JDWhiteWRX]

I was playing around with the bodywork today, nothing serious, just kicking around some ideas.

 

[El_Freddo]

^ just your typical arvo in lockdown

Will you look at flaring the guard (or reshaping it) to come out to that arc you’ve dummied up, or will you just create a cylinder to protrude out to that arc you’ve dummied up? I vote for the flaring/reshaping

I’ll be keen to see the vents in the bonnet for the air ducting. I presume it will be something like the Supercars where it exits out the bonnet above or just in front of the engine and out to the sides over the bonnet? Will you have anything to remove heat from the engine area?

Loving it. Keep up the good work and the pics! Best build thread ever with the number of pics in here!

Cheers

Bennie

[JDWhiteWRX]

I'm basically turning the whole body of the car into a "plug" and then taking moulds off of it and laying up either carbon or fiberglass panels in the moulds which will ultimately replace the majority of the steel on the car.

 

I've never done this stuff before but I've watched a lot of composite videos on Youtube and there are many different ways to go about creating a new shape. The first method I want to try is using my MDF (mount it rigid first) and then use tape or fabric to stretch from the MDF across to the steel panel. Then you paint it with epoxy to make it stiff, then some fibreglass, body filler to smooth it out. Essentially the tape or fabric creates the rough shape.

 

This is the tape method, skip to 6:00

 

https://youtu.be/H5vfodCokns

 

This is the fabric method, skip to 16:40

https://youtu.be/1Rae63gOE-A

[allpaw4]

This is AWESOME! Keen to see how this goes!

[JDWhiteWRX]

Played with some tape on it today, you get the idea. I think the fabric method will work better.

Attached Files

•  PXL_20210722_061111379~2.jpg   195.9KB   1 downloads

[El_Freddo]

Sweet. I’ve seen the Bad Obsession Motorsport boys use this same trick for their flares on the project Binky. It should looks sick once you’re done, and super lightweight too!

If you make the panels removable you could even have several bodies for different races/sponsors/looks etc. So many possibilities.

Cheers

Bennie

[JDWhiteWRX]

Work has begun on bringing the strength back into the front end, much more to come.

https://www.instagra...edium=copy_link

[RX25SE]

Nice. Those holes look like they were meant to be there!

[JDWhiteWRX]

Here is a little update on the work I'm doing to stiffen up the front end, it's really coming together now!

 

 

What I've done is bring tubes from the roll cage into the engine bay in a triangulated 3d structure that should prevent flex in any direction.

 

 

You can see the tubes are coming from the top and bottom of the A-pillar and then coming back to an additional mounting point in the center of the transmission tunnel.

 

 

 

close up of the notched junction

 

 

 

There will be another brace across the front of the engine but first I am going to take the engine back out and weld everything I've done so far. I also need to make a bracket and mount the dry sump oil pump to the engine to make sure there will be no clearance issues with the brace at the front.

[allpaw4]

Certainly coming together, keep up the updates! Looks like it's gonna be strong as a house!

Cheers,
Ben