Hyperblade

1 hour ago, mjrstar said:

could you maybe make 2 halves from some MDF, then use that to press the shape into aluminium and then weld together, if you get some O state alumimium its very workable...

Good idea, I have seen something similar done with 3d printed molds.

38 minutes ago, Unclejake said:

One small thing we used to do when I was racing was to move the car (hand push a few hundrend mm) in the pits a few times after each race. 

Our thinking was the hot calliper reduced heat dissipation from the hoy rotor so if we pushed the car further back into the tent every few minutes after the race the rotor would cool more evenly. 

I have no idea if that really helped or not though.  Ha.

This is actually a thing, pads create a hot spot, or so I've been told. Have been moving it after racing, but believe warping occured during race.

17 minutes ago, NickJ said:

Yeah/Nah/Maybe

Not really an easy short answer cos the variables are huge in composite design, more shape complexity just means more nasty tooling design!

With CF, rule of thumb, anything under 2mm precision needs post machining, of course with specific part experience and process/tooling/layup development that can be shrunk but this is a safe start for a one-off.

If I was making this for you, I would be going for a sheetmetal solution first to get further clarity on air flow requirements, its a dicky subject so before investing in tooling and materials, getting a good idea the plan works (just heavier) is a good start, Aluminium also gives great track day modification options when things don't work out as planned! In one day I could CAD and manufacture both left and right from 0.8mm Al sheet. In one day of design for carbon i'd be lucky to be unloading the first tool from the mill.

As for manufacture, not currently sure who would take this on sorry, most of the suppliers I have worked with would want to be making 100s. Technically I have all the gear here to do it, (mould making, vacuum pumps, ovens etc) but the cost might be prohibitive? 

 

Are you still WFH? i've got plenty of free time, happy to discuss in depth over a coffee/beer

Yeah was figuring all of that would be the case and was wishfully thinking it might have got easier, nothing is ever cheap being 1 off.

Sounds like I'm going the aluminium route, i've take the time pressure off myself as i want this done right, so I can spend some time mucking around and see how far i get.

Yep still WFH most days, thanks for the offer, but i'm probably ok to proceed at this point (but if you ever want to pop round and check it out just sing out), if not will give you a yell

Thanks everyone for the thoughts/advice appreciate it!

6 minutes ago, ajg193 said:

Is there a particular reason to stick with 13" wheels? (Cheap supply of tyres?)

 

Going up a size or two would remove a lot of bottlenecks 

I run the ex TRS Michelin slicks which are 13" and have amazing performance and cost me bugger all (new are $450 a tyre).

I have a fairly large stock pile of them and the car looks and handles better on them.

Yes, my life would be a whole lot easier if i ran 15" but it's worth the pain for the performance.

1 hour ago, NickJ said:

I've designed and had made exactly this from carbon, it can be done and CF is no dearer than the other options, its the tooling, time and consumables that add up...

Fiberglass would probably be fine, its the resin system that generally defines service temps, no real structural reason to use carbon over glass either.

I love sheetmetal, cheap easy and fast, thats where i'd be leaning as a first off, a diffuser cone to go from the 3d print to feed duct desn't look too hard? Not too hard to CAD, print A3 and then cut out.

Do you think it would be possible to do the duct and the plate as one piece in carbon/fibreglass? Does it have to be machined afterwards to give the tolerances required? Can you use PLA as the one time mold or does the resin eat it?

Anyone you recommend in Chch for the carbon/fibreglass work?

1 hour ago, nzstato said:

Choice of materials just depends on your comfort in fabricating them as such?

I think making it out of alloy sheet from a basic wireform is ideal.  Once you have the pattern you can flip your sheet to mirror the same on the other side. 

Keep the alloy section is small as your can get away from otherwise could cause some local cracking. 

Correct, was planning to do this myself (i have limited experience), but running out of time before race day and current thinking is to take a step back do a proper job on this.

3 minutes ago, GARDRB said:

Two questions,

One, does the larger aperture on the plate help if you're still only using the same-sized tube to get the air there? Could you achieve the same with a hole the size of the pipe and then vanes coming off the orange plate to distribute the air around the inside of the area? 

Two, have you considered/can you go to a thicker disk to give yourself more material to dissipate the heat

Current hole size is 1500mm2, tube is 2.5" (3100mm2) however the inlet on spoiler is 2" (2000m2)

New hole size is 4000m2, I'll be upgrading the tube to 3" (4500mm2) and the inlet to match. If i was 3d printing in metal or maybe doing it carbon fibre it's possible to get the hole on the plate to 4500mm2 but it's a more complicated shape.

So i really do need to increase the hole size, no room internally in the rotor for vanes, only have less than 20mm to play with and there is bolt heads in there as well. also don't think it would help, i need to get air into the center of the rotor and let the rotor vanes then pull it out.

I'm already running maximum disk size you can in a 13" wheel. there is 2mm of clearance between caliper and rim, to go thicker would require new calipers and going to larger rim.

Background: I'm warping rotors as the hats have not been designed large enough and so the air is going straight through and up the outside face of the rotor, I have a solution for that, but that means any air will escape where this plate sit, and that means there will be cool air flowing over one face of the rotor, creating a temperature differential which will cause them to warp again.

At $600 per rotor I can't afford to warp another set (If i can get temperatures into the correct zone they will last many years), so I have to make sure the air goes out the vanes evenly, hence the tight fit, but then I need to ensure enough air gets in, and larger is better in every way as you can always blank off the inlet.
 

I also only want to do this once, so prepared to spend time/money getting it right.

3 minutes ago, HumberSS said:

Youve got two radiused ends on the plate, I would start with two split tubes at each end of the curved slot then curve some flat to stitch in between then duct from there. 3D printing something would be a good way to get a feel for the shape but analog is sometimes easier to figure out on the fly to start with. 

Very true, good idea on an approach.

1 minute ago, ajg193 said:

Just use your brakes less you hoon

Sometimes when you racing cars with 500hp the braking zone is the only time you will ever get close to feeling like you can pass them

11 hours ago, Unclejake said:

With respect: I think you're on the wrong track as a rigid assembly connected to the sprung chassis (even with flexible air conditioning duct) but then attached to an un-sprung rotating strut will fail in alloy.

There doesn't look like much strength around the aperture  of the orange template and if I'm looking at it correctly it isn't designed to force air onto the rotor??? Perhaps I'm interpreting it incorrectly and you're trying to suck air out?

Is this a street legal car? If so I have no idea of the legalities.. but if it's a track only car air conditioning flexi-pipe and cable ties works pretty well for blowing air onto the rotors.

Always open to feedback.

Old one seemed to be ok for 5 + years? It's AE86 front struts so hose goes straight to chassis mount, so hose is taking all the flex. There so some pressure on the plate, but there is a tiny bit of flex in it? I am considering bracing the inlet against the strut to take any movement out of it.

Yeah the aperture is one concern i have, but i really need the biggest hole i can get. (Guess one option is to get the whole thing made out of carbon)

Air is coming in from the strut side from high pressure zone on the front spoiler through the orange pipe.

Race car only, rotors are seeing sustained 600c +, this is a 267mm x 25mm disk all under a 13" rim with a 12 lap race where i'm often in traffic, so getting rid of heat is a big problem, so it needs more than your typical race car.

5 hours ago, RXFORD said:

Might help to make a wireframe buck/template first. Can do it with tig wire or gas welding 'panel' wire.

Bend the wire to the shape you want, tape/tack weld them togethor, then you can lay paper over in sections to transfer onto Ali sheet. 

 

Good idea! hadn't considered that approach.

I need to go from this hole at a 45" angle up, right and inward towards engine bay and then adapt shape to to a 2.5" or 3" outlet to attach the hose on to, space is very tight.

Orange plate will be 2mm ali, currently thinking of having it laser cut instead of doing it by hand.

What options are there for achieving this relatively quickly and potentially at home? 

One I option i had thought of was to 3d print the inner and just hammer the aluminium around it, then get the seam welded (or try to do it in one piece), either way I would probably use a separate ali ring for the hose to clamp to. would end up being welded to the plate

2nd option might be the same inner but get someone to lay up carbon fibre around it (don't know anyone who does carbon fibre, or what that would cost me), but high temp area and not sure how specialised that is.

I can't see fibreglass withstanding temperature?

Any other thoughts on how to solve the problem?

18 hours ago, Mitch.W said:

4.9 will be great for drifting though…

would love to have a easy setup that works for grip and drift, I can get 2 different sets of front knuckles so that makes changing the alignment easy. Just always so tempted to run trs slicks but that requires big guards which makes it hard to make cool wheels fit for drifting 

19 hours ago, Truenotch said:

4.9 will be relatively short with 13" slicks. Ruapuna's straight is long - @Hyperblade can probably chime in here with the Starlet's diff ratio, RPM and 6th gear ratio to give you a better idea. 

So the only TRS tyres you can still get secondhand from the series are the old rears, (now the new fronts) which need 10" wide rim, so most cars require substantial modification to run them. Those charts were based off the smaller TRS slicks that runs on 8" wide wheels. so you need to think carefully about what tyres your going to run, it may be that 15" might be the more economical option (even though I don't like the look of them on old cars)

For grip, you will be wanting to aim for 185 - 200kph at the end of the straight which should be doable with your weight and power.

I went with 2nd-6th gears which meant launching in 2nd and using 3rd for hairpin 4-5 everywhere else then 6th for straight. 

But the alternative (and much nicer if you street drive) is to use 1-5th which can be beneficial for N/A cars as not using overdrive 6th.

Here's some diff/speeds (based on 54cm trs tyres) to give you an idea of where it would sit

You have lots of revs available which gives you a few options (let me know if you want me to calculate any other options).

SIL were bloody useless for me.

Try Pacific Seal the main guy is pretty knowledgeable.

On 08/03/2024 at 17:46, Tiger Tamer said:

I still haven't sorted the fuel system delivery. I had a look on K powers web site to see what they were recommending for there K power swaps.

They recommended this pump a Walbro 255L perhr pump for $255 US. Walbro 255lph HP Fuel Pump – KPower Industries

I did a google search on the pump and found I could buy the pump here in NZ for half the price in NZ dollars from this company. MSEL

and the pump price TI Automotive GSS342 255L/hr Intank High Pressure Fuel Pump Kit - Motorsport Electronics Limited (msel.co.nz)

Half the price in NZ dollars , 

I think I will be checking out K Powers recommended  fuel pressure regulator as well.

MSEL are great to deal with. Shipping is slightly more expensive but it's always next day delivery. Definitely can recommend them.

16 hours ago, kpr said:

probably fine long as the bends arent super aggressive.   assuming you are still using the 47mm throttles. probably best to have them on the shorter manifold, then can taper up in diameter sooner

Interestingly  i just tuned a k20  on my dyno.   had really short intake with big plenum  and big short headers.  done as expected.    made 202hp  and weak through the middle. 

85mm long = 

To me that looks to sharp on the inside of the outer runner (middle runners look fine throughout).

100mm long = 

110mm long

120mm long = 

5 hours ago, kpr said:

Also just looking back at your  vct/vvti map.     seems a bit low.  yours should have the 50degree vct pulley.  All the ones Ive done like more advance through the middle, pretty much max it out to 50. 

Yeah haven't changed pulley so will be 50 degree one, interesting, might have to end up putting it back on the dyno after the ITB's to look at all that. I have been offered the use of one, just need to upskill in being able to tune.

10 hours ago, kpr said:

probably fine long as the bends arent super aggressive.   assuming you are still using the 47mm throttles. probably best to have them on the shorter manifold, then can taper up in diameter sooner

Interestingly  i just tuned a k20  on my dyno.   had really short intake with big plenum  and big short headers.  done as expected.    made 202hp  and weak through the middle. 

48mm throttle plate, 46mm (same size as port) outlet to runner. 53mm inlet to velocity stack.

Are you going to remake the intake for it? Would be interesting to see another back to back but on k20.

On 23/05/2023 at 17:15, kpr said:

Yeah most people don't try anything that long, due to fitment / too hard basket in a lot of engine bays.   But its really where the advantage is.    when it comes to getting it dyno tuned. Id suggest having a way to try 20-30mm either  way from that 320 length.  is enough to see the power curve move around, to see if your in the right place.   even though can shuffle it a bit with the vct , there still a litte bit to be had getting it bang on. 

If going to make a plenum for it. make it big as possible. same deal with feed pipe.

Yeah kinda re the skunk2 manifold,    the runner length thing works just the same on turbo stuff though.   It keeps coming back to the packaging thing and being a diddle to make.  shiny parts sell. 

How important is getting the runner straightended up before the port?

e.g. 150mm length

vs 85mm

Obviously the longer I make them the smoother it gets, but do need to take into account velocity stacks and potentially having to go 90 degrees with them to fit the total 320mm length in.

Small post to say a big thank you to @h4nd for coming round and getting an Oscilloscope trace of the Honda S2000 Speed Sensor (VSS) I've been having issues with (only taken me nearly 2 years to get round to it.) just waiting on Link to respond with their thoughts now, but have one potential solution we think should solve it.

Traces are below if anyone else needs similar in the future

16 hours ago, fletch said:

Do you have many other high speed inputs on the link? I think I read that that while they can read up to 10khz, if you have have a few high speed inputs, the max frequency each input can process drops.

Could have my wires crossed, I was doing some research into which ecu to run and read it somewhere. Was to do with people trying to run all 4 abs sensors to digital inputs and maxing out the processing ability of the ecu

Just Crank and Intake/Exhaust Cams.

From what I have read on their forums what they advertise takes that into account, so you can actually go higher then stated normally as your not maxing them all out.

Often people put a divider on the honda speed sensor, but the latest Link ECU's should be capable of handling it (and they do a plugin version now)

2 hours ago, h4nd said:

PM me, I may have time Wedns, or maybe loan you a scope and show you the "Auto" button.

Hall effect? Can you jig a wheel/cog into a drill /vice?

Yep Hall effect, it's positioned directly against one of the gears (nothing special I can see on the gear)

I don't know the size of the gear it's against, so not sure how accurate it would be replicating it, I could 3d print something, but I assume you have to put some metal in it for it to work.

I think it needs to be fairly high rpm to recreate the issue, I think outside the range of most drills/lathes.

Have PM'ed you

43 minutes ago, NickJ said:

I also have a small scope that would happily see that, won't be until next weekend that I would be free though.

Thanks I'm in no rush so If h4nd and I can't work something out will give you a bell.

I need someone with an Oscilloscope and who knows how to use it to come round and help me diagnosis a speed sensor cutting out at 5000hz (120km/hr+) (according to the Link ECU).

It's in a racecar so I can't drive it on the road, however I can recreate the issue on the jack stands, and I have a DTM connector (and know the pinout) in the engine bay to the sensor so will be relatively easy to intercept the signal?

It's a Honda s2000 AP1 gearbox, and a Link G4X Xtreme X which has been double checked by link (capable of 10,000hz)

I also have a spare speed sensor that can be bench tested if required.

I can only do this during the day either during the week (I work from home most days) or weekends as the car is to noisy for the kids/neighbors...

I'm located in Prebbleton and happy to pay for your time.

So since it's of the same era. I've wired up a 84 Toyota starlet motor from scratch before, which was a pain.

Here's a starlet wiring diagram.
\

In my case I needed a 4 pole switch (not cheap e.g. $80+) to allow it to park correctly, getting off/low/high is the easy part.

The wiper motor needed 12v and 3 wires from switch.

Then the switch needed 12v as well then 3 wires to the wiper motor and you have to jump 2 of the pins (dotted)

Pin 2: Park

Pin 3/4 connected via jumper (dotted)

Pin 5: Low

Pin 10: (not sure can't read what I wrote, I think it livens up the other circuits within the switch

Pin 11: 12v source

Pin 12: High

8 minutes ago, shrike said:

Keen for start up/running videos and shed skids

Are your J160 all stock internals? Or have you had some mods done (Circlip?) Any idea how it'll go with many revs?

I'm assuming power and torque are within specs for it?

A friend races his RX7 with a 13B and a J160 and it's been pretty reliable for the most part (he's raced it since 2008).

However last round he blew 4th gear, so the circlip mod may be worth looking into.

The issue is a lot of the boxes for sale are all very high k's and it's not as easy as it used to be to find cheap good condition ones.

RE flywheel, I'm not up to speed on it all your issues, but could you run an insert like the K2F flywheels run (inserts can be bought separately)?

4 hours ago, Honda Ass Dragger said:

TBH the G5X is a bit of a disappointment

It still requires driver boxes for DI - where as a Motec doesn't

Yeah and for the price you don't even get a PDM built in. On the flip side at least g4x maps transfer over and plug a and b are same as g4x series so easy upgrade. But a bit underwhelming tbh.

11 minutes ago, shrike said:

Also I'm not sure of an aftermarket ecu that runs direct injection but I could be wrong

Link have had one for a while

G4+ Force GDI https://dealers.linkecu.com/force-gdi 4 Cylinder only though, ($3000+)

And have their new G5 Voodoo Pro https://dealers.linkecu.com/G5-Voodoo-Pro ($5000+)

Not a cheap exercise!

12 hours ago, Roman said:

Yeah I'm using SW20 calipers at the moment with a Primera disc. 

But I've got an MX5 setup here I was looking to fit at some point. 

Going back to a smaller/lighter non vented disc, and better pad options for MX5s. 

That's one of the most important things for choosing a caliper I think, finding something that actually has good pads.

If using anywhere near the track then yep it's a big deal, if you make sure you have a good range available you will save yourself a lot of money in the long run.

More choice means more competition so harder for the manufacturers to price gouge you.

So calipers from MX5, GT86 etc are good choices as they are often tracked as standard.

1 hour ago, mjrstar said:

There are places like carbotech that will reline backing plates to whatever you supply (if they don't have an off the shelf for you). I run thier xp8 series in my civic which are legit in my opinion..

Generally though you are still limited to a smaller selection of compounds, my personal experience of bonded mintex was not a good one. But it's going to also depend on the use case, as proper track racing is quite different to say hill climb or street.

Another option is picking a caliper that lets you water jet cut a pad down from another common pad size, this is what I did with my rear AE86 disk setup, I just had wilwood polymatrix pads cut down to suit, $25 to cut down per pad, and once they have template it's easy as.

If your looking for long lasting brakes, bigger and thicker pads are what you want to go for, it helps them last a lot longer from the heat and just helps all the components around them.

17 hours ago, Tiger Tamer said:

It would have to be all set at the same height as it is now as the boot floor is directly above the tank. It could be done as he has done it or finding something from another donar car. I have sealed the inside of the tank with POR15 so it would have to be stripped out to be able to weld to it somehow as being able to reach it would be a problem. I would think there maybe some cert requirement coming to welding fuel tanks mods, but don't know for certain.

This is what he did with the S2000 pump. First pic is with the piece he cut out to shorten it.

That looks like a nice simple self contained approach definitely worth exploring further, when you add up all the fittings etc it really adds up quickly if doing a external setup.

3 hours ago, mjrstar said:

You could mount the baffle off the fuel pump cradle, from memory the fg falcon has a plastic tank and cradle thing the kind of clips in with a spring loaded nubbon.

Good idea! And could fill the rest with foam to help stop it moving as well.