Hyperblade

Thanks for posting up about the engine building, it's really interesting seeing the work involved!

My understanding is they are both your old parts! They are getting some good use now.

Not allowed to mount aero to suspension, nice try

Thanks @kpr and @Snoozin

Finished Version, just waiting on one mounting point to arrive. Ended up sticking out further then what i was originally planning as I moved it back from the diff for clearance. But shouldn't have a negative affect on the aero (opposite probably), and could still go out another 200mm within the rules! Can always cut it down later if needed Only concern is it getting hit by another car, so painted the back red to stand out...

Here's a better pic of the diffuser., strakes have been glued and screwed

Hah! should have seen my splitter after going into the gravel, came out with a rock garden on top of it, when they pulled me out the car started to submarine further in, still finding gravel in odd places. I have a spare splitter ready to go if i break it, beauty of plywood was a simple pattern and just drilling a few holes. It's a good entry to the diffuser, wish i had it as simple! Rear wheel drive makes it a lot harder. Hard to tell too on a hill climb, as opposed to a circuit where you can push the limits a little more without major risk.

I'm not a big fan of ali for a splitter, if you go off road it has tendancy to dig in and fold over on itself. The strength over a larger area means you have to put in a serious amount of support work, especially around the edges. (My splitter goes all the way back to the firewall) I think 4mm ACM might be better for this potentially, even 4mm plywood would be pretty good as you have a good structure for it and would be a bit more robust. That diffuser looks fairly aggressive! I've only gone for a 7degree angle (vertically only) as going for more really requires a good flow of air clean air to it (i.e flat floor) which i don't have. You might find if you made it less aggressive it will be more effective, also if you have a rear wing or gurney flap it can help it. Thanks for sharing, always good to see how others have done it!

Talking with someone in the know on aero, he recommended doing a double diffuser to deal with the air on top, i can't at this stage due to the fuel tank, but might be an option in the future. Currently it will still eventually find a way out, but just be a lot more inefficient. A better option might be to work on the lead up to the axle so you have less overall air going over the top. However you do need to be careful with Diff cooling then. Front: 400lb Rear: 350lbs

Yep, i lowered the pressure to the rear during the racing and got it driveable but it wasn't stopping as well after that. Just the act of stomping on the brakes forced the front to dive a lot and so the rear to go up, so required me to be a bit less aggressive on them to keep the car flatter (probably also need some harder springs at the front). Will be trying it on Friday, so fingers crossed it's dry. Hard to know if it will help as the interaction of the live axle makes things a bit more tricky for us to get the air leading into the diffuser right.

Thanks! The ducting mods made a big difference. I normally struggled to keep up with a competitor down the straight and instead could overtake him. I did take a bit of weight out of the car (alternator, doors etc) so i'm probably about even at the moment for adding it.. The splitter has had a big negative affect in the braking zones as the balance isn't right so i'm having to brake sooner then I normally would to keep the rear on the ground, but through the corners it is adding noticeable downforce and allowing me to turn in better. I'm hoping the diffuser balances it all out. Yep end plates and strakes added, just forgot to take a photo.

And finally to balance out the splitter I created a diffuser, again out of 12mm ply as that was easiest (prototype for now), mounting was really tricky but got their in the end. Have made some strakes for it and it's getting painted black to match splitter. It's height and angle adjustable, and is again quick release as i'm guessing it won't fit on the trailer. All ready to go for the last club day of the season Sun 5th May (Next weekend).

Got that all repaired and going into the last race of the season had a few things to sort out. Brakes were leaking at the rear still, so i pulled the calipers apart and found the seals were not the same size as the standard Toyota ones, really annoyed as they were done here in CHCH at great expense by a well known company. While I was at it I replaced the front ones as well just to be safe as they looked like they were starting to leak as well. I've had some 1mm Titanium brake pad backing plates made up for all the calipers which I'm hoping will protect the seals until I can replace the calipers all round with proper race ones. Been a bit concerned going into Winter that if I have to race in the rain that I won't be able to see out of the windscreen due to fogging (I do run anti fog) so I hacked the original windscreen venting to take a feed from a bilge fan which will take hot air off the floor (above the exhaust). Had the diff in to be checked after the hit it took, and have changed ratio from 4.3 to 4.5 so hoping that's going to give a nice boost at the end of the straight.

Of course the first club day I had the splitter on and got punted off the track (first time for me). From Behind: I was very lucky, minimal damage all round, his wheel hit mine and the rear axle took the brunt, he then ran down the side of the car and hit the front splitter which protected the front of the car, I ended up with a couple of bent brackets and turnbuckles, but actual splitter was in pretty good nick. Aero wise the splitter also had a major impact in high speed braking where i was getting huge weight transfer to the front and so the rears were locking, diffuser was now on the cards. However I have dropped my PB from 1:37.187 to a 1.36:200

Splitter Finally! got round to finishing off the splitter, I ended up going with 12mm marine ply (the lightest i could find) which ended up being 12kg total. I chose ply after looking at all the options, I wanted it quick release which meant it needs to be held up by the front and back with nothing in the middle. ACM was flexible and pretty heavy for the size you would need. I also wanted it to be easy to replace if it got hit for mounting I went with Stainless Steel Turnbuckles (8mm Jaw Jaw) with 8mm tie rod ends (all sourced from AliExpress). Some minor grinding on the tie rod ends and making up the ali rear adjustable brackets, and I now have a really solid mount. It's also adjustable in height and angle and takes my weight standing on the front. The splitter is all quick release and I can install in about a min, which is great as the car won't fit on the trailer with it.