Sam's build thread

[Sydneykid]

Yes, Wilwood rotors. They are a "GT 72 Curved Vane Rotor", part numbers 160-8398 and 160-8399. Are they good or is there something better that I should be looking at? They're not exactly cheap. I'm not sure how to cross-reference them to look for other options.

They are a good rotor, I'd stick with them. Pretty decent size at 355 mm x 32 mm they should work very well. I'd put the wear down to the endurance compound pads, they don't wear (as fast) so the rotor cops it.

OK, thanks. The rotors are pretty expensive so I'd prefer to chew pads if I'm going to go through one or the other quickly! I don't mind noise, dust, and a bit of extra effort required when cold, if it still works ok and will hold up better on the track. I actually have a set of BP10 pads that came with the kit, but the seller told me they were no good for track use so I didn't even bother fitting them. Would they be worth trying or am I just going to cook them after a couple of laps? I don't really care about staying with the same brand, I have Carbotech xp8s in the factory rear calipers, and had their xp10s in the factory front calipers. I find it hard to cross reference pads between brands, the pads are backing plate 7416 which have all the Wilwood compounds you mentioned available and a couple of others. Where can I find which Hawk pads will fit/suit?

Hawk list lots of Wilwood calipers (pretty much every one ever made), you just look up the caliper brand and type and it will list the available pads. Parts Lookup | Hawk Performance

Wilwood BP10 is pretty much a heavy duty street compound, would be OK for hillclimbs, supersprints, time attack etc but not suitable for 15/20 minute track day sessions, the heat build up would be too much for them to handle. Polymatrix A are similar to Hawk HT10 and would be an OK choice for you to try.

As I posted above, Hawk Blacks are my go to pad for performance and value for money. They also serve as a useful base line, I often use them in cars/drivers where I am not sure what they need. Then after a few sessions I get feedback, download the data etc and I then can make a call on which direction to go. For example, in a car with little to no downforce, if they creep up on the brakes then I can use a DTC70 or maybe even a DTC50 at a stretch. But if they have a slam on the brakes style then DTC70 would be a step too far. More suitable would be HT10 or DTC60 at the highest initial bight. Caution, Hawk Blues are an endurance compound, stay away from them for your purposes.

Thanks heaps for your detailed response!

No Problem, happy to help anytime.


Cheers
Gary

[seangti]

Sam/Gary/anyone else - any recommendations for street usable track brake pads that will have reasonable rotor life (and preferably ok pad life)? I fitted Wilwood H pads with my new Wilwood front brakes earlier this year, and while I've been very happy with the performance (yes they dust a lot and squeel a bit, but I can live with that), they have chewed out the disks like crazy, I think I'll have to replace them after heading to Wakefield next week (they've done ~20 laps at Tamworth, ~20 laps at Wakefield, half a dozen hillclimbs and maybe 10,000 street km). Pads look barely worn! I really don't want to mess around with swapping pads every time I head to the track at this point if I can avoid it.

I've been running QFM A1RM for a few years. About to fit my 3rd set of pads onto the same rotors (DBA 4000). Rotor thickness is still over 24mm (new at 25mm), so can't complain about rotor wear. I'm not sure what car you're running, so a heavier car may push the pad temps on track, but Polo being light has never been a concern. I'm also running a brembo 4 pot caliper. Pending the caliper (if polo), you may need to get the compound done custom for the backing plate - which is easy enough, just send some old pads and they'll do that.

[metalhead]

They are a good rotor, I'd stick with them. Pretty decent size at 355 mm x 32 mm they should work very well. I'd put the wear down to the endurance compound pads, they don't wear (as fast) so the rotor cops it.



Hawk list lots of Wilwood calipers (pretty much every one ever made), you just look up the caliper brand and type and it will list the available pads. Parts Lookup | Hawk Performance

Wilwood BP10 is pretty much a heavy duty street compound, would be OK for hillclimbs, supersprints, time attack etc but not suitable for 15/20 minute track day sessions, the heat build up would be too much for them to handle. Polymatrix A are similar to Hawk HT10 and would be an OK choice for you to try.

As I posted above, Hawk Blacks are my go to pad for performance and value for money. They also serve as a useful base line, I often use them in cars/drivers where I am not sure what they need. Then after a few sessions I get feedback, download the data etc and I then can make a call on which direction to go. For example, in a car with little to no downforce, if they creep up on the brakes then I can use a DTC70 or maybe even a DTC50 at a stretch. But if they have a slam on the brakes style then DTC70 would be a step too far. More suitable would be HT10 or DTC60 at the highest initial bight. Caution, Hawk Blues are an endurance compound, stay away from them for your purposes.

No Problem, happy to help anytime.


Cheers
Gary

Excellent, thanks again Gary. I ordered some bp20s yesterday because they're very cheap in this application and I can get them overnight, so I'll see how they go. My brother is using Hawk Blues on his mx5, but says he goes through disks fairly quickly too, which further confirms your advice. His disks are much cheaper to replace, so for him it's less of a problem!

I've been running QFM A1RM for a few years. About to fit my 3rd set of pads onto the same rotors (DBA 4000). Rotor thickness is still over 24mm (new at 25mm), so can't complain about rotor wear. I'm not sure what car you're running, so a heavier car may push the pad temps on track, but Polo being light has never been a concern. I'm also running a brembo 4 pot caliper. Pending the caliper (if polo), you may need to get the compound done custom for the backing plate - which is easy enough, just send some old pads and they'll do that.

Thanks Sean, good to have another option. Not on a Polo, I'm Andrew with the Corvette.

[sambb]

The Escort made 221hp atw strapped normally and a repeatable 210hp strapped hard on 98RON. 110hp atw per litre sounds pretty strong for that type of engine. They are going to do more sessions on different fuels to see whats what.
Gary what are the rules re fuel in IPRA?

[metalhead]

Pretty healthy!

[Sydneykid]

The Escort made 221hp atw strapped normally and a repeatable 210hp strapped hard on 98RON. 110hp atw per litre sounds pretty strong for that type of engine. They are going to do more sessions on different fuels to see whats what.
Gary what are the rules re fuel in IPRA?

If you can buy it from a pump at a commercial service station then it's legal, obviously this includes E85. Plus there are CAMS/FIA approved fuels Elf, Martini, Power Plus etc but no one I know uses them anymore because they give very little if any benefit and cost multiples.

CAMS General Requirements Schedule G https://www.cams.com.au/docs/default...sn=a8f566dc_12


BTW, no leaded fuel has been allowed since 1st July 2019.

Cheers
Gary

[sambb]

I was down there today. They are going to give the head a once over and check for me that the valves on the large port head I bought are sealing aok. Being a complete head with cams fitted and the inlet and exhaust cams tied together with the tensioner chain, some of the valves are down a bit. The head was stored on a sheet of core flue but I just want them to vacuum test it to make sure nothings bent and they are all sealing ok.

Yep the Escort is definitely destined for IPRA. They don't seem too interested in E85 but said that they are confident there's some left in it once they decide on the fuel they'll run and then get it dialled in for that. Yeah they did mention that Avgas is outlawed I assume because of the lead in it?

[sambb]

In other news I'm going to stick some parts up on the parts for sale board. Even if there's nothing on there for interested people, keep in mind that I've wrecked a car previously and have all sorts of spares. Many I will retain but it cant hurt to ask.

[Sydneykid]

Yep the Escort is definitely destined for IPRA. They don't seem too interested in E85 but said that they are confident there's some left in it once they decide on the fuel they'll run and then get it dialled in for that. Yeah they did mention that Avgas is outlawed I assume because of the lead in it?

There is unleaded Avgas but it has the same problem as leaded Avgas, a slow burn rate (fires in aeroplanes etc). Which doesn't really suite a high rpm engine (eg; Cessna Lycoming or Continental engines max is 2,700 rpm). E85 has huge advantages, next to zero preignition possibilities, lower combustion temperature, lower water temp, lower oil temp, never foul plugs, run much higher compression ratios (we run over 15 to 1) as a result more torque and of course more horsepower. There is only one downside, typically an engine uses ~25% more so you need to carry more fuel at the start of a race, but by the end of the race it's back to the same carrying weight as petrol ie; not much.

Please don't talk them into it, I'll be OK with keeping the advantage

Cheers
Gary

[sambb]

So stupid me thought for some reason that the strut tops in our car had asymmetric bolts which meant the tops would only fit into the tower in one orientation. Don't know why I thought that but then the penny dropped and I measured them and low and behold they are symmetrical. What a dumb ass. So after oggling it for a while I realised that if I twisted the tops into a diagonal orientation on the slider, , set them in the furthest back position that I would get way more caster yet the pivot would stay laterally more or less where it was meaning I wouldnt loose any camber. After really going through front tyres at SMSP and not getting them to work properly at a recent hillclimb where I was smashed by a competitor, I figured a change was in order.

Before & after passenger side. East/west runs across the pic. I'm facing the back.
Can see how much more angle there is in the strut and that at full droop. More accentuated at ride height.

Before pic shows how far forward the tyres were in the guard beforehand. This is the passenger side front of the car with the front of the car on the left. I achieved that with adjustable subframes and caster offset rear LCA bushes. The after pic shows that now adding extra caster at the top too has pulled the wheel back in the guard a little more which is better for guard clearance with the track tyres.
I lost about 1/4 - 1/2 a degree of neg camber doing this. However I do have a small amount of movement in the front of the subframe with the eccentrics to get maybe 8mm a side at the bottom and also my TT RS ball joints which are slotted, are currently bolted up in the middle of their range so there's 5mm left in those too which should get me back to 3 degrees if I need it but I'm not sure I will with all the caster I have now.. But I should be able to find enough in the bottom to square it all up at a good neg camber setting.
For now I've only done a toe with my toe plates. I'll get it on a machine soon to get the front end sorted and also get rear beam toe out numbers so that I know where I'm at for an upcoming re-shim of the stub axles so that I can add more rear camber and more toe out.