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hey all,
i am currently looking at 2 different projects to do to my car for racing.
im a draftsperson (technical drawing) so i can measure and design things and get them made... only i am not the best with cars... yet...

the catch is that i want to be able to remove them if required without them damaging my car at all.

firstly i want to make some relatively cheap, removable wheel arches, basically just sum soft plastic or hardish rubber to stick out 2 inches from the wheel arch.
this is to avoid stone chips since i want to get into khanacross, club rally.

secondly i want to put some kind of under body protection. i work alongside sheet metal fabrication shops and have contacts so i was thinking of drawing up a large sheet of thin guage metal that can be bolted and unbolted to the underside.
this will stop any grime from flicking up as well as minimise damage if the worst happens and i bottom out at all...

the things that im finding hard to work out is:
with the wheel arches, where can i bolt the rubber to? can you bolt it inside the guards? what is on the other side? how will it support itself if it isnt bolted right on the edge as well?
and with the underbody protection, how can i leave some ventilation so that the exhaust doesnt overheat? i can have the sheet metal perforated below where the exhaust runs but would this be enough?

...isnt this fun!!!

For the wheel arches, I'd consider looking at the Mazda optional mudguards front and rear. If these aren't heavy enough for you, consider emulating their mounting method of using screwing to the inside plastic section of the guards and double sided tape to the outside of the body.

For the underbody protection, be careful not to block the airflow out from the rear of the engine compartment, this is the main outflow for the cooling air from the radiator.

Oh, and capital letters can be fun, too!

Haha capital letters are for b*tches!
Kiddin, thanks Alf.

I do want something a little more than the Mazda ones, I have them currently on the back but I think I need something more comprehensive...

Yeah im really not too sure how I'd go about the underbody protection, as Alf said I'd need to leave an escape path for engine air, I'd need to allow airflow around the exhaust system, and I'd also need to make sure that there is room for movement of the tailshaft...
Wait, the tail shaft doesn't move technically does it? The diff is fixed right?
Hmmm...
I can leave an opening where the existing one is for engine air, and i can either perforate along where the exhaust system runs or I can criss cross by chopping out big diamond shapes...
And I can have it completely open below the tail shaft. Since in the case of a bottom out, i dont want the underbody protection to bend and foul the tailshaft...

This is all possible and plausible, just a bit daunting i must admit...

Phew that was hard to write with CAPS!

CAPS are easy, what you want to do is hard.

have you got rolled gaurds metris?

if not you might be able to do a very cheap rally/4wd mod using conveyor belt rubber for some stone gaurding..

basically 2.5\" wide conveyor rubber strips that you self tap screw to the wheel arch (on the inside/under side), into the lip that is rolled up to give clearance when gaurd rolling. will mean holes in the gaurds but in a location you wont see them and the \"flares\" will be removable

as for the under tray protection... try to stick to plastic or alloy... will weigh a ton other wise..though alloy wouldnt cost afew hundred

thanks irwin83r,
i was looking at going to clark rubber and getting some but after talking to some of the engineers at work, we agreed that the weight of thin guage sheet metal will likely be less, so i CAD'ed some workshop drawings and they got sent to the factory last night...

i found that the lip of the guard in the front is quite tiny, im not sure there is enough to screw or bolt to it...
I had planned to bolt it good and proper near the bottom of the guards on the sides, with 4 bolts or screw, that should hold it in place well, then i was going to clip it to the inside plastic of the wheel arch, which wont be holding weigh but just keeping it inline. Im also going to use plastic clips so that in case im driving the i hit something with the guard, the clips will break before it pulls the metal of the car...
I'll have another look at the front guard lip again, but im pretty sure its too small...

With the underside protection, I found a UK rally website where they sell this semi flexible light weight pvc sheets, theyre very expensive but Im hoping to find something similar in Aus that is hopefully a bit cheaper...

I'll let yous know how the guards go... im presuming there will be some fine tuning needed... tin snip time!

Hey irwin83r,
You might know, will these guards or under body protection, or chassis stiffening put me out of the production race category?