New member with racecar!

All aspects of tuning,modification and repairs to the BX 16valve.
Gary C
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Post by Gary C » Sun Jan 12, 2014 5:21 pm

Hi.

Short sort of overview.

Temperature is pita on a road car, once on track it is a nightmare. Clean out the rad, then clean it again, and again. Block off the ports, put some central heating system cleanser in, put cap on, shake the rad until your arms ache, leave it in overnight and then shake it again. wash it through thoroughly. You can of course buy a new one to save time and energy. If the heater is still fitted you can use that to help cool the engine but the driver will sweat!

Close up any gaps between rad and frame, you want the air going thru the rad not bypassing it.

We use standard Bendix pads on "Bertie", other pads "race compound" tend to not last too long, nor do cheap pads. Use test days or practice sessions to bed in pad sets ready for use later in the season. File the edge of new pads first.

After each track session pop the pads out, clean them and the brakes, deglaze the discs so they are ready straight from the off.

Are you allowed to fit bigger anti roll bars?

Take it you have to use road tyres. Depending on length of race you may have to adapt style of driving to suit the front end. Road tyres do not like turning corners at the best of times so I try and make some corners "double apex" to lessen the steering angle, it all depends on the circuit layout.
Tyre pressures can make a lot of difference, again it depends on race distance as they are going to go up the longer you are running. Apply chalk to the tyre walls to see how much roll you get over 5 laps, alter pressures, try again. Take temps too if you can. I like the car a bit loose at the rear so if you do not have to run one make of tyre put nice grippy ones on the front and some well worn cheapies at the back, makes it a tad more rwd in feel but if the ar@e end goes you can keep your foot down to pull it back.

If you are not allowed lsd then the left foot will need to be used to feather the clutch coming out of tight corners.

Remove any item from the car that is not required within the rules.

Happy motoring!

Mungous
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Post by Mungous » Sun Jan 12, 2014 8:58 pm

frog wrote:It would be far too hard to adapt the Xantia Activa setup to the BX. Better off starting with a Xantia Activa.

One of those threads had some peoples set ups.

I had Xantia double diaphragm's on mine but swopped back to regassed Valver spheres, which is nice for a daily.
I have occasionally day-dreamed of an Activa system on a BX, but then laughed and forgotten about it... :lol:

My red car still runs standard BX spheres all round, and they are great for road use - Whitey would not be very comfortable as a daily!

Mungous
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Post by Mungous » Sun Jan 12, 2014 10:33 pm

Gary C wrote:Hi.

Short sort of overview.

Temperature is pita on a road car, once on track it is a nightmare. Clean out the rad, then clean it again, and again. Block off the ports, put some central heating system cleanser in, put cap on, shake the rad until your arms ache, leave it in overnight and then shake it again. wash it through thoroughly. You can of course buy a new one to save time and energy. If the heater is still fitted you can use that to help cool the engine but the driver will sweat!

Close up any gaps between rad and frame, you want the air going thru the rad not bypassing it.

We use standard Bendix pads on "Bertie", other pads "race compound" tend to not last too long, nor do cheap pads. Use test days or practice sessions to bed in pad sets ready for use later in the season. File the edge of new pads first.

After each track session pop the pads out, clean them and the brakes, deglaze the discs so they are ready straight from the off.

Are you allowed to fit bigger anti roll bars?

Take it you have to use road tyres. Depending on length of race you may have to adapt style of driving to suit the front end. Road tyres do not like turning corners at the best of times so I try and make some corners "double apex" to lessen the steering angle, it all depends on the circuit layout.
Tyre pressures can make a lot of difference, again it depends on race distance as they are going to go up the longer you are running. Apply chalk to the tyre walls to see how much roll you get over 5 laps, alter pressures, try again. Take temps too if you can. I like the car a bit loose at the rear so if you do not have to run one make of tyre put nice grippy ones on the front and some well worn cheapies at the back, makes it a tad more rwd in feel but if the ar@e end goes you can keep your foot down to pull it back.

If you are not allowed lsd then the left foot will need to be used to feather the clutch coming out of tight corners.

Remove any item from the car that is not required within the rules.

Happy motoring!
Thanks Gary - that is some very good info!

I have noticed my temperatures sit very high - and I am not allowed to run an air-to-liquid oil cooler either. Not great for oil control when the oil temp sits at around 140C for a 30 minute race!

I have wondered about fitting a deeper, larger capacity radiator (that fits in the same sized hole) - I see there are some alloy ones available on eBay, but they seem mad expensive! I will try to give mine another flush while waiting for my head to return.

I do seem to go through brake pads like there's no tomorrow - whether Bendix, Ferodo, EBC or random cheap brand. The main problem in NZ is that there are very few suppliers who do any BX pads at all! I know larger Xantia calipers and discs are used by some, but I am (currently) limited to running 14" wheels...

ARBs must remain standard - although I could upgrade my rear to a Ph2 one (if I could get one - there's not that many Ph2s in NZ, and even fewer being dismantled).

Tyres are one of my biggest issues in terms of lap times - I am mandated to run the original 195/60R14 tyres, and they must have a treadwear rating of over 180. Which means there is nearly nothing decent available. Currently I am running some horrible BF Goodrich things. They are black and round, but otherwise pretty rubbish. Amazingly noisy around corners too. Driving around their weakness has become my focus. After about three laps the rears go off and give me some very oversteery turn-in - but that's the way I like it too! It does get a bit silly after 20 minutes of sliding around though, and the rear tyres actually seem to be wearing out faster than the fronts.

I am hoping that the organisers allow me to run 15" wheels and tyres next season, as that will allow me to get some proper tyres that so I can collect proper data - currently I am running about 35psi front and rear (hot), and am contemplating upping the rears to get some more progressive movement. What pressures do you run in your spheres? I imagine also super-low at the back to help with weight transfer?

No LSD allowed either, so I am doing a little left foot braking to try to limit wheelspin on corner exit.

The other racecar in the pic above is similar spec to mine, but crucially has an LSD and R888s on it - I drove it for a practice session and I reckon its about 3-4 seconds a lap quicker (about 1.25 vs. Whitey at 1.29 at Hampton Downs, near Auckland).

I have to reassemble and refit my head this week, and then have my next race on February 16th.

Gary C
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Post by Gary C » Tue Jan 14, 2014 9:06 pm

If you are allowed to change rads for another make have a look at Fiesta RS turbo ATRAD4 at burtonpower.com

We have just bought one and will give it a try this year. It fits in the hole, ports are about in the right place just need to knock up a couple of brackets.

ollie
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Post by ollie » Wed Jan 15, 2014 12:37 pm

Sorry to hijack this as I'm not a racer! but I have few questions:

Whereabouts can you get genuine bendix front pads from? as I've allways preffered them but last time I chased around nobody seemed to have any.

Also interesting to see your notes on tyres/ rear end bias as the best (most predicteable) handling BX Ive even had was a combination of Yokohama (A539?) on the front and some 60 mph remoulds of dubious origin on the back.

On the radiator front, I might be stating something silly but what is wrong with a Turbo Diesel Rad as they are pretty huge compared to the 16v one?

Ollie

Gary C
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Post by Gary C » Wed Jan 15, 2014 8:15 pm

Ollie, iirc Bendix pads came from GSF.

Diesel rad is large but then the oil burner does seem to have much more space in the engine bay to fit it in. Imagine sticking a 16v inlet manifold in the bay!

Mungous
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Post by Mungous » Mon Apr 07, 2014 8:53 am

Just had a good weekend's racing in Whitey. By good, I mean one where nothing broke off or snapped!

I managed to qualify about mid field for the first race, despite having never even been to the track as a spectator, let alone actually driven the circuit. The first race was going well until I thought I started suffering fuel surge around right handers. But stopping in the pits for a splash and dash made no difference. Oops. Turns out there was some electrical gremlin under the bonnet, as resecuring all the connectors and earths seemed to fix it.

Race 2 was a reverse handicap, which meant I started from the front row. I even managed to hold the lead very briefly! But then the fast cars caught up. Finished 11th of 45.

After taking Gary's C's advice, my engine temperatures were OK, if not great, and the brakes stood up to the punishment quite well.

I'm still struggling with tyres and handling though. The back end still feels a bit too soft, despite running Hydractive spheres gassed to only 5 bar. The tyre issue I hope to be able to work around, but I'm at a loss as to how to improve handling. I'm still contemplating the single sphere 405 rear end, but am open to suggestions as to alternative set ups that others have used for a racecar.

Try to spot the BX!

Image

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frog
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Post by frog » Tue Apr 08, 2014 11:51 am

I found it!

Mungous
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Post by Mungous » Tue May 13, 2014 8:36 am

Had another good weekend of racing at the invitation of the NZ Alfa Romeo Owners Club. 50th anniversary of the 105 series meant there were many GTVs out there (mainly much faster than me and Whitey), but there were a fair few Suds, 33s, Alfettas and Sprints for me to play with.

Image

Image

I tried some decent tyres for the first time (Dunlop Formula R) and couldn't believe the difference! Although they were second hand and I totally shredded one of the fronts with excessive wheelspin.

Image

Had a small tap from one of the faster Suds as it went past me, so now need a new indicator and to learn how to do my own panel beating/painting!

Image

Mungous
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Post by Mungous » Thu May 15, 2014 7:21 am

And a spot of video action for those who like such things...

https://www.youtube.com/watch?v=nhjeIy6kdW4 (watch out for a Sud missile at 5.30!)

https://www.youtube.com/watch?v=0H4ULA0G3vI

Mungous
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Re: New member with racecar!

Post by Mungous » Mon Sep 29, 2014 6:54 am

First race of our new season here, and I have been allowed to upgrade to 15" wheels:

Image

Yep - Xantia alloys and a can of black paint! Not the lightest wheels, but they were free... I think they look quite good (i.e. you can't really see them):

Image

15" wheels also meant I can run some better DOT-rated Dunlop Direzza Tyres. Which turned out to be worth about 2-3 seconds per lap (my times dropped from 1.30-1.29 to 1.27-1.26 without really trying too hard)!

But, as is so often the way as soon as you change something, it meant something else went wrong:

Image

Image

Seems that the OEM-spec Mintex/Bendix pads don't last a qualifying session and one 30 minute race now! Same pads I ran last year without drama too. I was having a great race with an Alfa 147 and didn't notice the brakes for a lap or two - that was stupid of me, as the melted backing plates (and caliper piston) show! :oops:

Mungous
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Re: New member with racecar!

Post by Mungous » Wed Nov 19, 2014 5:09 am

So I have got me this stuff to fit:

Image

Should stiffen up the handling a fair bit!

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Vanny
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Re: New member with racecar!

Post by Vanny » Wed Nov 19, 2014 3:12 pm

Where on earth did that come from? Or more importantly, what car can i pull that off?

I've seen similar in the past and tried to get a set from my ill fated hydraulic trailer build.

Mungous
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Re: New member with racecar!

Post by Mungous » Thu Nov 20, 2014 3:51 am

It is off the arse-end of a Peugeot 405Mi16x4. The subframe on that car is the same as a BX 4x4, but the hydraulics are set up to be a lot stiffer for the 405 (the BX still ran a sphere for each wheel).

Having a single shared sphere should have a double-whammy effect on handling - there will be much less springing medium (especially if I gas the sphere to a low pressure), and no ability for pressure to be displaced into the sphere on the other side while under lateral load - a bit like a shuttle valve would do.

Gary C
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Re: New member with racecar!

Post by Gary C » Fri Nov 21, 2014 8:04 pm

Mungous wrote:First race of our new season here, and I have been allowed to upgrade to 15" wheels:

Image

Yep - Xantia alloys and a can of black paint! Not the lightest wheels, but they were free... I think they look quite good (i.e. you can't really see them):

Image

15" wheels also meant I can run some better DOT-rated Dunlop Direzza Tyres. Which turned out to be worth about 2-3 seconds per lap (my times dropped from 1.30-1.29 to 1.27-1.26 without really trying too hard)!

But, as is so often the way as soon as you change something, it meant something else went wrong:

Image

Image

Seems that the OEM-spec Mintex/Bendix pads don't last a qualifying session and one 30 minute race now! Same pads I ran last year without drama too. I was having a great race with an Alfa 147 and didn't notice the brakes for a lap or two - that was stupid of me, as the melted backing plates (and caliper piston) show! :oops:
I have some similar looking pads. The faster you go the quicker they wear out. We swapped worn Bendix for new standard Pagids and destroyed them in 2 meetings.

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