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Keri-WMS

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Posts posted by Keri-WMS

    Wms Starlet 4 Pot Brake Kit & General Discussion

    in WMS Brakes

    Posted

    That shounds brilliant if we could have a set to print off, to see if its close, i just need to find a way of getting it printed now! lol.

    Unless you know that it will fit under 15" Rays Engineering TE37's?

    Not sure how I missed this post! I don't have any Rays....if you're TOTALLY stuck for getting them printed but would be interested in a kit if they do send me a PM with your address and I'll snailmail you a couple of printouts....

    :thumbsup:

    Bent Rear Axle

    in Chassis & Suspension

    Posted

    Looks like you need a re-shell - it looks twisted to me? (only from the photo though)

    Any insurance company would write that off stright away as well if you're thinking of claiming, you won't get it repaired.

    Unlucky, but lucky it wasn't the driver's door as that could have been very painful.

    Glanza Snow "drift"

    in Video Gallery

    Posted

    Not bad! If you'd grabbed another gear as it started to go too far, full right lock and gunned it to 75%ish of the rev limiter you could have dragged the car up the straight with the back sitting out there at that angle...and slowly pulled it in straight as well.

    If it snows here again I'm going to have to do a few vids as well - on private land of course. :rolleyes:

    Look At This

    in Intake, Turbo & Exhaust

    Posted

    yeah we found the same with the 3sgte in the mr2. 500bhp is about the absolute limit on the road, 400bhp makes a nice going road car and i can built that prietty reliably.

    Drag racing is another story though, were at 955bhp with that, can't drive that on the road at all, spins in 5th frm just flooring the accelorator at 100mph lol, but drag its capable of 9's

    sorry for going off topic but i take it you had some cossie background, thats where i cut my teeth building engines ;) built my first one at 14 :D

    Tim

    TB Developments

    Not personally, they just got talked about a lot as I've got a Mk1 Escort "project". While we're off topic my mate has a 240bhp n/a YB in his Mk1 on Jenveys, but he's selling the engine to make was for a 2.4 YB headed 300bhp beastie, Holbay/Warrior (or "Diamond-something") alloy block. :rolleyes:

    My Mr2 In The Snow ;d

    in Video Gallery

    Posted

    Toyota had so many people crash the Phase 1 Mk2 MR2 that they changed the suspension geometry for Phase 2 - on!

    - Phase 1 = "supercar" setup, better handling but very twitchy (snap oversteer) which most normal people can't hack.

    - Phase 2-on = "safer" setup, loads of understeer and slower turn-in to try and make them harder to spin.

    (I'd be having the Phase 1, with #cough# uprated brakes and a Woodsport V6 conversion please!) :rolleyes:

    Look At This

    in Intake, Turbo & Exhaust

    Posted

    well said, some people forget about the big picture sometimes when sellecting parts and building cars. I mean i've built some nice 600bhp mr2's in the past, very fast but you get them on the road and its just spinning up all the time and a well built 350bhp will leave it for dead.

    Tim

    TB Developments

    Reminds me of the Cossie YB-T lads, found that up to a fairly fixed power limit the car got faster round a track (up to about about 380bhp from memory) but beyond that it just gets more and more undrivable (peaky) and the lap time gains were minimal...esp given the drop in reliability as the engines became more highly strung.

    As ever there are always exeptions, but there was a lot of talk about it a few years ago.

    Look At This

    in Intake, Turbo & Exhaust

    Posted

    I don't know the ins and outs of of turbo selection (only read a lot of the Graham Bell stuff), but the graph/map you see could really be called the "choose your best compromise" - increase each factor (bigger turbo for higher revving engine) and you will have some downsides (bigger turbo results in more lag).

    There's much more to it of course but that's what people going for the "ultimate" all the time forget, the boring sounding "best compromise" is normally faster 99% of the time while the "ultimate" is faster 1% of the time.

    Same goes for brakes, fit 380mm rotors and 8-pots to a Rover Mini and you WILL win pub top-trumps with your mates....but try and built a competitive car round it!!!!!

    Wms Starlet 4 Pot Brake Kit & General Discussion

    in WMS Brakes

    Posted

    First off: Just a heads-up as I have made the PDFs more accurate - there's more room in the centre than was shown in the previous versions so I've overwritten them with the corrected ones (ie the links are still correct.) :p

    Don't suppose you do anything for Hondas do you?

    Er, my rat style EG5 shed/runabout (while MR2's 4AGE engine is being rebuilt)/battering ram is going to get some new toys soon - seeing as I might as well as it's available as a phase 1 testbed! Will the resulting kit fit all the other EG chassis Civics? (better send me a PM then email before we get lynched).

    I bought it as my brothers ram each other's cars out of their spaces when they visit each other, and it's got a towbar (ie, I win)...every single panel is now hammered!!!! :lol:

    Wms Starlet 4 Pot Brake Kit & General Discussion

    in WMS Brakes

    Posted

    get some buddyclub p1 alloys to test :lol: lol

    hoping i can get these on without spacers etc

    Tim

    TB Developments

    Have you got the alloys (14/15/16"?)? Print out the 275mm profile PDF, stick to to card, cut it out and shove it up there!

    I'm tweaking the PDFs a bit as the caliper is shown very slightly too big near the hub/underside, but the outside is right.

    Wms Starlet 4 Pot Brake Kit & General Discussion

    in WMS Brakes

    Posted

    Dad's wondering if you do a Corolla E12 kit? Not to go offtopic like.

    No problem! Not as yet, it might be that I've got something that'll fit, but I don't have a hub to work with so I don't know....

    -----------------------------------

    I've just checked on the wheel that arrived today and can confirm that the 275mm kit fits in the 15" Speedline with plenty of spare room! No wheel spacers, no change to the factory offset.

    Biggest we can go without messing about is 280mm.

    WITH messing about (add a few mm to an alloy bell's flange, more bell offset, running the pads a tad low on the rotor.......MAYBE 300mm is possible as Speedline have designed a better than average wheel in terms of caliper clearance. :lol:

    What are the most common alloys on race/rally/sprint Starlets? These Speedlines I would assume?

    What Do You Think About This Guys

    in Intake, Turbo & Exhaust

    Posted

    I remember the fastest way to get my Mk1 Uno Turbo off the line (running 1 bar) was full throttle first until it JUST hit boost then a hard change (to keep it spooling) to 2nd with part throttle until mid boost then a smoother change to third, full boost and play with the throttle to try and stop it breaking into wheelspin.

    So in first you are just being really harsh to a 1.3 low compression engine (no boost) so no wheelspin - and it won't bog or wheelspin on the change to 2nd but you've got a few revs into the turbo from the end of first.

    That said, it was an uncontrollable peice of #####! Used to break into wheelspin in 4th in the wet if you pulled out to overtake someone at 40mph.

    Brake System Theory

    in WMS Brakes

    Posted

    This is something I wrote for a BMW site's wiki, but it applies to all cars so I thought it might help!

    -------------------------------------------------------------

    Basic checks:

    First off, ensure the callipers are in full working order (no sticking pistons, seals etc) and the brakes hoses are in good condition before embarking on any upgrade. Also check the servo is working properly if fitted (a duff servo normally gives you a hard pedal with a lack of braking force) and that the master cylinder seals are good (leaking seals give you a soft pedal, often slowly "sinking" if held under pressure).

    What can be improved?

    There are a lot of closely interrelated aspects surrounding brake system operation, many areas can be improved but at the expense of another area. This makes everything a compromise, here are the aspects with their effects on performance etc:

    Brake "power"

    ie torque at the wheel for a given brake fluid pressure. This can be improved in several ways:

    1 - Larger discs, this in effect increases the leverage that acts on the wheel. Downsides are increased unsprung mass (and rotational mass due to the larger diameter), a slight increase in cost if it's a re-drilled one-piece disc or a larger increase in cost if it's alloy bells and rotors.

    2 - Higher coefficient of friction in the pad material. Downsides are that in most performance pads they work better when warm/hot, and full race pads hardly work at all when cold, plus increased cost.

    3 - Larger pistons in the caliper (and/or smaller master cylinder piston/s). This increases the mechanical advantage that the system gives your foot over the force applied to the back of the pads, but like all forms of increased leverage the longer the "lever" the longer the travel needed at the input end. In the case of brakes, the added clamping force at the pad is offset by a longer travel / softer pedal.

    Unsprung mass,

    This is the effect of the mass of the brakes fitted to the strut, where they are not properly "sprung and damped" by the suspension like the chassis is. The lighter a brake system is, the faster and more controlled the suspension action can be, giving the car more grip. The downsides to lighter brake discs, is that they heat up faster due to the lower "thermal mass", but lighter calipers, pads, alloy bells and mounting brackets all give you "free grip".

    Rotational mass

    The lighter and smaller the brake disc (and wheel/tyre/hub etc) the less energy is needed to spin it faster or slow it down. So a lighter and smaller brake disc will give the car better acceleration, economy and braking (if the brakes magically still worked just the same!). The downsides are reduced brake power, reduced cooling from the smaller disc vents and reduced thermal mass.

    Fade (pad) resistance

    This is the amount of heat the brake pads can withstand before they overheat into "brake fade", this feels like you have a hard pedal but no brake power (similar to a failed servo). In the olden days pads used to "gas", where the glue in the material boiled and producing a thin layer of high pressure gas that lifted the pad off the disc using the same principles as a hovercraft uses! This lead to people drilling (and grooving) their discs to release this gas. Modern brake materials no longer gas in anything like the same way, so drilled discs are of FAR less use than they used to, and given that they can crack the main reason people buy them is for the "look". Grooved discs DO still have a place as they scrub at the face of the pads, and with many race pads they are needed to stop the pad surface "glazing".

    Fade (fluid) resistance

    This is the amount of heat the brakes can withstand without the fluid boiling, when the fluid boils the bubbles created are easily squashed by the pressure created when the pedal is pressed, making the pedal sink straight to the floor and allying almost no pressure to the pads at all! This is probably the most dangerous form of brake problem and for the few seconds it happens the effect is as bad as a burst brake line. Fluid boiling can be reduced by:

    1 - Running a fluid with a higher boiling point.

    2 - Changing the fluid regularly as water is absorbed by most brake fluids, and of course only needs 100 degrees C to boil. Also once brake fluid HAS boiled it's resistance to boiling is actually reduced, and next time it will boil at a LOWER temperature!

    3 - Using cooling air from the brake duct to cool the caliper.

    4 - Using cooling air from the brake duct to cool a brake fluid radiator.

    5 - Running a brake fluid recirculating valve. This clever gadget cycles the fluid into the caliper then back out and up into the main fluid reservoir, this keeps the caliper cooler and stops a stagnant volume of fluid from sitting in the caliper and getting very hot.

    Heat reduction

    This is mainly about keeping the disc cool to stop it "warping" and keep the pads cooler so they can operate properly. You can reduce disc temperatures by:

    1 - Having a larger disc with bigger, more efficient vents and larger area to be cooled, the downside is added unsprung/rotational mass (although mass helps in another way, next....).

    2 - Having a heavier disc, this provides more "thermal mass". Thermal mass works because it takes twice as much energy to heat twice as much mass to a given temperature, so if you double the mass while keeping the energy input constant you HALVE the temperature (before cooling efficiency etc starts to come into play). The downside is added unsprung/rotational mass.

    Disc "warping" resistance

    It should be noted that brake discs juddering through the pedal are not "warped" in the way many people think, in most cases it's because road pads (which are abrasive) have been overheated and a high-spot has formed. This high spot gets VERY hot and into a changes into a different and much harder form of iron. Of course the new hard area is more resistant to the pad's abrasion and so as the material around it is worn away it becomes higher, which makes it hotter, and therefore even harder....and so on. The discs DO warp, but only when you press the pedal and this one high spot gets much hotter, rapidly expanding and warping the disc. The things people miss are that (1) the disc returns to a mostly non-warped state as soon as you back off the brakes or take the disc off the car for inspection, and (2) machining the disc won't fix it as there is still a hard spot in the iron waiting to start the whole process again once the abrasion or use continues! Upgrade pads often work by "smearing" their own pad material onto the disc rather than abrading the disc, thereby dodging the high-spot vicious cycle.

    Resistance to high temperatures by all components in a performance/race application

    If you assume that the brake system will be used and a hard and sustained way (trackdays etc) then the components ARE going to get very hot no matter what cooling you use, but there are ways to allow them to survive the temperatures and work very effectively for a sustained period.

    - External piston dust seals on performance calipers often burn off, but they can be omitted without causing any problems in most cases.

    - Brake discs get very hot in the area that's in contact with the pads and expend with huge force. In a one-piece disc this makes the disc form cone-shape as the vented "rotor" part expands but the "bell" part stays cooler and unchanged, in (very rare) extreme cases the vented part can crack right off the bell! To reduce these forces there are two options, (1) fit an iron rotor to an aluminium bell (aluminium expends faster with temperature than iron, so the cooler bell partly "keeps up" with the hotter rotor as it expands) and (2) fitting a "radially floating rotor (there are radial slots in the rotor or the bell with sliding "bobbins" in them, this allows the rotor to expand totally freely, with no force applied to the bell)! Floating rotors are very expensive though and are almost exclusively for race-cars only - although BMW have recently used the principle on the M3, the discs have aluminium bells with radial spoke-like pegs, and the cast-iron rotor "floats" on these pegs! Also large light-weight rotors rely less on the effects of thermal mass, and more on effective cooling vents to cool the brakes on each straight section of track.

    - Race pads will continue to work happily way after normal pads would have totally failed, and often get better the more abuse they get, and race brake fluid can withstand the continued high temperatures.

    - Brake ducts are very handy as the high speeds on the straight pump much more cooling air into the brakes than on a road car.

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