Post a pic of your real car

[Div is back]

:0 That car is gorgeous! I think its called a Hyundai Coupe in the UK

I have no idea, I don't think it's even released in Europe yet. I do know they had plans to bring over the Genesis Sedan.

 

[homeforsummer]

Doesn't fuel over there work out to be something like $8 a gallon? That seems like it would make the idea the anti-tempting.

It's pretty expensive, but my trump card is that I actually drive very little distance at all, so fuel is one of my lowest living costs. I've only done about 2.5k miles since I bought my Mazda eight months ago...

Lol whoops. I just accidentally a Xedos 9 (Millenia/Eunos 800) 2.3 Miller...

Great engine, awful gearbox. Luckily this won't be an issue.

On a semi-related note, will that be taking you down to Roo's for UKGTP13?

 

[Famine]

I was planning on it. Then I drove it and changed my plan - it's a nail. I will be taking Blue down to Roo's - and you're welcome to leave DM here and snag a ride.

 

[Joey D]

It's pretty expensive, but my trump card is that I actually drive very little distance at all, so fuel is one of my lowest living costs. I've only done about 2.5k miles since I bought my Mazda eight months ago...

Holy hell dude, I drive 2,500-3,000 miles a month!

 

[homeforsummer]

I was planning on it. Then I drove it and changed my plan - it's a nail. I will be taking Blue down to Roo's - and you're welcome to leave DM here and snag a ride.

Cheers 👍 I think I'll do just that. Quite looking forward to taking a closer look at Blue, actually. And I'm sure you'll want a snoop around DM.

Holy hell dude, I drive 2,500-3,000 miles a month!

That's why I'm not too bothered about fuel. That, and the fact that you could pick a car out of a hat and I almost guarantee I could get better economy out of it than 99% of people without even needing to drive like a hypermiler.

 

[Revheadnz]

I have two MX-3s with the 1.8 V6 the 2.5 V6 is based on

I see what you did there/are planning on doing. I agree wholeheartedly with this.
Has anyone done it before?

 

[Paulie]

bird at the beach nice and quiet this time of year so i get less abuse

Great car mate.👍

Nice, I've been keeping a beady eye on ebay for old Firebirds and Camaros, they're very tempting for some reason.



Not that one. They don't sell the Genesis in the UK. Nor the coupe at the moment, either. Hyundai's UK lineup is really rather dull. The best drivers car they make is the i10

Don't you generally go for eco-cars? Yet you consider a muscle car. Anyway, we don't get the Genesis in Australia either, it's a real shame. It's not like I'm rich enough to get one though.

It's about $2.89 around my house.

Can't imagine paying that much.

Welcome to the rest of the world.

I see what you did there/are planning on doing. I agree wholeheartedly with this.
Has anyone done it before?

What's that, take the 2.5L V6 and throw it in the MX-3?

 

[Famine]

I see what you did there/are planning on doing. I agree wholeheartedly with this.
Has anyone done it before?

What's that, take the 2.5L V6 and throw it in the MX-3?

I don't have the 2.5 though. But it has been done. Many many times - generally called the ZE swap (the high output 2.5 is called the KL-ZE, whereas the 1.8 is the K8).

But Revheadnz is absolutely on the money and no, it hasn't. There's a few reasons for this. The KJ is fundamentally untuneable - you can maybe bump the redline up 500rpm and the power curve should permit another 20hp or so, but everything else is in a fine balance. The supercharger isn't there for power, but to compensate for compression losses of the 5-stroke cycle, so you can't turn it up (oneoneoneone). It's also kinda rare and expensive. It gives about 10hp more than the far more common ZE and the ZE can be tuned after the fact. It also doesn't really fit - one mount has to be fabricated (oh no!), there's possible interference with the left-hand side of the firewall (hammer) and, with a supercharger between the banks, the bonnet/hood doesn't close (hammer). There's also one or two minor mechanical issues I accidentally solved in the process. It does have two advantages over the ZE - 50lbft more torque and a frickin' supercharger.

But I have a recipient MX-3 and a donor KJ sitting on my drive for a combined cost of £1,020 (plus getting them here, less parts sold). I have an MX-6 manual gearbox and MX-3 flywheel - could probably do with an MX-6 clutch, but the MX-3 one will do for now. And I'm not a retard so I don't want to tune a 210hp/210lbft engine in a FWD car - I want it quick and fun and those numbers are the last port of call before the land of diminishing returns.

It has never been done - and the first the MX-3 communities I'm in will know about it is when it has been and I turn up in it

 

[homeforsummer]

Don't you generally go for eco-cars? Yet you consider a muscle car.

Correct and incorrect. I "go" for most cars, really, though I suspect my appreciation is wider than most which is why I get drawn into discussions about eco cars. Most people don't like them, and generally I see that as being down to lack of education on the subject, and cynicism borne from a misguided assumption that eco cars will somehow spell the end of "fun" cars.

Ironically, the technology of many "eco" cars is such that their prices are beyond my reach. In an ideal world I'd have one (an original Honda Insight, an Audi A2, a Smart etc), though perhaps not as an only car.

It's worth remembering too that in going from Fiesta to MX5 I've sacrificed 20% of my fuel economy for 100% more power and 50% better acceleration I still love sports cars, muscle cars and so on, it's just that my appreciation doesn't stop with performance cars.

So yeah, I'd consider a muscle car (it helps that I'm an absolute sucker for Americana). At the moment though, I'm quite happy enough with the Mazda and most things with a V8 are out of my price range.

 

[Jondot]

It's pretty expensive, but my trump card is that I actually drive very little distance at all, so fuel is one of my lowest living costs. I've only done about 2.5k miles since I bought my Mazda eight months ago...

I've done about 12,000 since then. Or about £1400, depending on how you want to look at it.

*Opens vodka bottle*

I was planning on it. Then I drove it and changed my plan - it's a nail. I will be taking Blue down to Roo's - and you're welcome to leave DM here and snag a ride.

Is Blue the (red) Accord, or am I way off?

Incidentally what happened to the Explorer plan? Have they all rolled over?

 

[Famine]

We're still after a dog-car so that's an ongoing plan. And Blue is the red ATR, yes

 

[The Vanishing Boy]

^ OMFG! Is that the rare Accord Type-R!? 👍

 

[Famine]

Yeah - I'm sure I've posted it before?

We've had it since October.

 

[homeforsummer]

And IIRC there's a member from the Netherlands on GTP who has a Championship White one too. It's probably only a handful of pages back.

 

[Famine]

Yes - he's had his since October too

 

[wfooshee]

The supercharger isn't there for power, but to compensate for compression losses of the 5-stroke cycle

Perhaps an explanation is is order for those unfamiliar with Miller cycle engines.

Basically, the power stroke is longer than the compression stroke, which increases volumetric efficiency. The mixture that was compressed for a certain distance of piston travel expands for a greater distance. The intake valve opens at the normal, expected time, at the start of the intake stroke. It closes late, though, after the piston has well started the compression stroke. The supercharger's purpose is not to so much to create "boost," but to keep the intake "contained" in the cylinder, as opposed to blowing back into the manifold as the piston starts to rise. There's a "perfect" balance between intake pressure and backflow at the intake valve. Increasing intake pressure by excess supercharger boost apparently negates the volumetric gain of the Miller cycle.

And it's still a 4-stroke engine, as the piston makes 4 passes through the cylinder before you repeat a cycle. The "fifth" stroke would be the dead travel of the piston upward before the intake valve closes, I guess.

The result of having the combustion product expand for a longer time than it was compressed is more power from less fuel.

 

[Famine]

Yes.

In a normal 4 stroke petrol engine (Otto cycle) you have four phases:
1. Intake (suck)
Piston is at top of chamber. As the piston descends, the inlet valves open, allowing fuel/air mix (or air, and the fuel is injected) to enter the chamber.
2. Compression (squish)
Piston is at bottom of chamber. Inlet valves close so the chamber contains all of the fuel/air required.
3. Ignition/Expansion (bang)
Piston is at top of chamber. Spark plug ignites the mix, driving the piston down.
4. Evacuation (blow)
Piston is at bottom of chamber. Exhaust valves open and, as the piston ascends, exhaust gases are driven out of the chamber. As it reaches the top, the exhaust valves close.

Miller cycles - and there are two Miller cycle engines available, both Mazda - have an extra-long intake phase. I mean really long. Well into the compression phase. This would normally mean some of the fuel/air is driven out by the piston advancing and it'd reduce the compression ratio (there's less stuff to compress into the same space, so it isn't compressed as hard). The supercharger combats this, by forcing more air into the chamber, well above the compression ratio of the piston. So where Otto cycles are suck-squish-bang-blow, Miller cycles are suck-suck-squish-bang-blow, but it absolutely requires a supercharger to function.

What you end up with is an extremely efficient engine for the capacity - Mazda's publicity machine said the power of a 3-litre and the fuel economy of a 2-litre. The reality is it has slightly more power than their high-output 2.5 (~210hp), the same torque as a 3 litre (~210lbft) and probably comparable fuel economy with the 1.8 (I got 32mpg in the 1.6 ton Xedos 9 for the same journey I get 34mpg in the 1.1 ton MX-3).

And this is going into a 0.98 ton MX-3.

 

[Paulie]

So this miller cycle engine you've got to put in your MX-3 is a 2.0L? It's certainly interesting, not sure how upping the boost would have a negative effect exactly though. Plus, an MX-3 weighs less than 1000kg? That's reasonably impressive I must say. And cudos to you for being completely original and also realising that despite the in-ability to increase the power much on these miller cycle engines, you won't need to do so in a FWD car. I look forward to seeing it. What do these engines run like? Smooth? Can you at least add a sports exhaust for that nice note and a little extra power? Will you post videos?! Sorry for all the questions.

 

[Famine]

It's a 2.3 - 2,255cc. Also, MX-3s weigh about 1,100kg, but Marvin won't have any insides or soundproofing. I'm even shedding a couple of pounds each corner on wheels

The supercharger isn't there to generate power, but to compensate for loss of compression by adding more air. Up the boost and you add too much air and too much compression, leaning the engine out and losing power. It's all in a very fine balance

I've only had the engine on a couple of journeys in the existing car and, yes, it's smooooooth despite the slushbox. The torque curve is pretty flat, like all the K-series V6s, and the power curve is stupid - it's a plain geometric increase from 2krpm upwards and the only reason it only has 210hp is because the limiter kicks in at 6k. If we could raise the limiter by even 2-300rpm we could get another 10-15hp. I wouldn't want to venture much over 500rpm more, simply because the balance is so fine and there's probably a 10% tolerance built in between the limiter and the safe limit (for warranty purposes)...

I have acquired a pair of stainless 3-1 MX-6 manifolds and a downpipe, which will fit any K-series V6 but I'm probably going to fit those to Red as she is fundamentally more important. I may get another set, or throw some money at a full custom system. After all, I might not be able to do much to the engine but an MX-3 exhaust can't be the most effective way of hauling those exhaust gases out - the MX-3 uses the sane principle of 1" bore per litre for an NA car, which would mean it'd need another half-inch bore even if it weren't forced induction, which it is. Probably won't give much extra power, but every little helps. Hell, even as it is it'll put more on the road through a manual clutch and the MX-6 'box I have than a torque convertor and a slushbox.

I will post many, many pictures and videos but only once it's finished. I'm not a fan of the "gunna" school of car modifying, so I'll only be boasting about it when it's done. The "fagpacket" (or "beermat" if you prefer) numbers say 215hp (188whp) and 220lbft in a 985kg/2170lb car, a low 6s (maybe flat or slightly under) 60mph time and a low 13s quarter mile (I want a 12.999 ) at just over 100mph and it should reach the gearbox's limit of 155mph with the wheel/tyre combo I have (we think 163mph will be the aero limit, but that's ignoring the splitter 'cos I have no way of measuring the effects). But it's not meant to be a drag car, so we also have a low-fade brake set-up probably capable of close to 100ft stopping distance from 60mph. There's a plan to cannibalise some larger calipers but it's not a priority since it'll stop, repeatedly, just fine It's not going to be a monster, but it should be quite quick and good fun with it. For a total spend of £2,000 including the cars...


But the engine has to get in the car before it'll go anywhere. Theory is all good but it means absolutely sod all until put into practice.

 

[Paulie]

Well it sounds very nice, and again, I love the originality of it all. Is it true that bigger brakes can't decrease stopping distance because the tyres can only give so much grip before locking up?

 

[Famine]

Pretty much.

Basically, if you can lock your tyres up you have enough braking force to exceed grip and you have your shortest stopping distance. Increase the grip - with a softer tyre compound or, on a much smaller scale, wider or lower-profile tyres (both of which have really tiny effects - barely noticeable in stopping distance terms) - and you might have more braking force available and reduce your stopping distance. But you might also no longer be able to lock your tyres, which means you aren't braking as efficiently. You'd need higher-friction pads and/or discs to generate more braking force and, once you can lock your wheels again, you have your shortest braking distance again. And the cycle begins once more

Track pads, larger calipers, more pistons, various disc flavours (drilled, grooved, slotted and any combination), braided brake flex lines and uprated fluid (DOT3 (glycol) to DOT4 (glycol), DOT5 (silicon) or DOT 5.1 (glycol)) don't improve stopping distances, but do improve braking either through pedal feel - so you can more accurately brake - or fade reduction - allowing you to do exactly the same hard stop again and again in very quick succession. Brake components are essentially heat distribution devices - you're slowed by friction of pad on disc (caused by fluid on pistons) and tyre on road. Friction is just heat and uprated fluid can absorb more heat (higher boiling point) and uprated discs can dissipate it more quickly, allowing the same stop to be done again more quickly.

 

[Sureboss]

Great engine, awful gearbox. Luckily this won't be an issue.

With that gearbox, I suppose you won't need to fit any tracking devices to the car, because if it were nicked, just follow the line of fluid

 

[KSaiyu]

These last few pages have been enlightening. Ashamed to say I'd never heard of a MX-3 or 6 before.

 

[Paulie]

Pretty much.

Basically, if you can lock your tyres up you have enough braking force to exceed grip and you have your shortest stopping distance. Increase the grip - with a softer tyre compound or, on a much smaller scale, wider or lower-profile tyres (both of which have really tiny effects - barely noticeable in stopping distance terms) - and you might have more braking force available and reduce your stopping distance. But you might also no longer be able to lock your tyres, which means you aren't braking as efficiently. You'd need higher-friction pads and/or discs to generate more braking force and, once you can lock your wheels again, you have your shortest braking distance again. And the cycle begins once more

Track pads, larger calipers, more pistons, various disc flavours (drilled, grooved, slotted and any combination), braided brake flex lines and uprated fluid (DOT3 (glycol) to DOT4 (glycol), DOT5 (silicon) or DOT 5.1 (glycol)) don't improve stopping distances, but do improve braking either through pedal feel - so you can more accurately brake - or fade reduction - allowing you to do exactly the same hard stop again and again in very quick succession. Brake components are essentially heat distribution devices - you're slowed by friction of pad on disc (caused by fluid on pistons) and tyre on road. Friction is just heat and uprated fluid can absorb more heat (higher boiling point) and uprated discs can dissipate it more quickly, allowing the same stop to be done again more quickly.

This was all pretty much how I figured things worked, but while I had the smartest man on GTP, I thought I may as well ask to confirm. My pedal feel on my Ute sucks. It's probably a cheap upgrade to better fluids and stuff, but I have more pressing issues currently.

 

[daan]

Friction is just heat and uprated fluid can absorb more heat (higher boiling point) and uprated discs can dissipate it more quickly, allowing the same stop to be done again more quickly.

You should try drilled and ventilated brake lines. I've heard they work brilliantly. 👍

 

[kayman]

This was all pretty much how I figured things worked, but while I had the smartest man on GTP, I thought I may as well ask to confirm. My pedal feel on my Ute sucks. It's probably a cheap upgrade to better fluids and stuff, but I have more pressing issues currently.

All commodore pedals are pretty crap. My old VT was the same.

You can get slotted rotors for your ute for pretty cheap, VT ones bolt straight on and are slightly larger (i think they hook up to the same caliper). Mate that with some DBA pads, braided lines and some better brake fluid and thats probably your cheapest option for a brake upgrade.

 

[homeforsummer]

These last few pages have been enlightening. Ashamed to say I'd never heard of a MX-3 or 6 before.

Just for you then:

Mazda MX3

Came with either a 1.6 I4 (90bhp) or 1.8 V6 (130-odd bhp). Famine has two of the latter.

Mazda MX6

Came with a 2.0 I4 (not available in the UK though, to my knowledge), and two flavours of 2.5 V6, the more powerful of which you also couldn't get in the UK. Shared a platform with the Ford Probe.

Mazda Xedos 9/Millenia

Luxury barge from Mazda's short-lived Lexus-like brand. 2.0 or 2.5 V6s, or the 2.3 Miller Cycle supercharged V6 like the one Famine has. Mazda also made a Xedos 6, which was smaller, prettier and came with either a 1.6 I4 or a 2.0 V6, as far as I remember.

Miller cycles - and there are two Miller cycle engines available, both Mazda

You might be interested to know that the 1.2 supercharged engine that we'll see in the upcoming Nissan Micra is also a Miller-cycle, as far as I'm aware.

 

[Famine]

You might be interested to know that the 1.2 supercharged engine that we'll see in the upcoming Nissan Micra is also a Miller-cycle, as far as I'm aware.

Heh. I guess Mazda really were onto a good thing then. The only article I've read about the Nissan unit gives this comparo:

Otto/Miller
1.2 litre/1.2 litre
80hp/99hp
78lbft/107lbft
63mpg/71mpg

Oddly, the follow up Mazda2 Miller unit doesn't use a supercharger. I have no idea how this works, since Miller cycles require supercharging. I imagine it's marketing and it's actually an Atkinson cycle.

 

[wfooshee]

Well it sounds very nice, and again, I love the originality of it all. Is it true that bigger brakes can't decrease stopping distance because the tyres can only give so much grip before locking up?

Going back to this. If you can lock the tires, you have enough brakes to stop.

Whether you can do that same stop two or three times, or even finish the stop if you're going fast enough, is a function of brake size. Brakes convert kinetic energy to heat through friction, and that heat has to go somewhere. If they can't shed it to the air fast enough, bad things happen. First, brake fluid boils, which kills pedal feel and brake pressure. Secondly, pads can break down. Both of those contribute to "fade," basically the loss of brakes after hard use.

My Probe GT didn't have enough brakes to stop hard from its maximum speed. It would be fading before the stop finished. Miatas have bigger rotors than the Probe, at a signicantly lower weight. It would be pushing it to make two hard stops from 80mph.

People ask, "Well, why big brakes, then?" As Famine pointed out, heat capacity. Bigger brakes can hold more heat, and with a larger surface area they can radiate the heat away faster.

The tire contact patch stops the car, the brakes convert the kinetic energy to heat and dissipate that heat.

Most street cars have vented rotors on at least the front wheels. That's those holes at the edge of the disc, with air passage inside the rotor. That increases surface area for heat radiation.

Drilled or slotted rotors do not have any heat advantage. Those holes or slots do not disspiate heat, they vent gases that build up under the pads, keeping the pads on the disc for better stopping and better feel. Unless you're stopping hard from the high side of 100 over and over, you won't need drilled or slotted rotors.

 

[Slick Rick]

Lol I bookmarked the last page, want to read up on all that stuff on the miller engine when I have time....should be revising for exams