Advice needed on going single.

[caseys]

Why have gauges? if you get the BEST ecu you can and have it mapped by the BEST then there is really no need for gauges, i think they look messy and im trying to steer clear of gauges... apart from my gearbox gauge.

 

Oh I agree, it's why I'm ripping all of mine out now running Syvecs installation - the ECU can monitor and more importantly *react* far quicker than I can. I was just interested to know what gauges he has / sticking with if going with EMU.

[Ricky49]

I have gauges and Syvecs, when I had my fuel injector problem it was the AFR gauge that made me realise I running really rich then randomly really lean not the ecu.

 

Gauges aren't the prettiest thing as but are a good thing to have as an extra pair of eyes. My next visit to Ryan I'm going to get everything set up through the ecu and keep my gauges still.

[adnanshah247]

pretty decent setup, only advise i can give is dont cut corners, use the expensive parts and make the install strong as possible. i.e. heat wrap, replace rusted bolts, use good quality gaskets, general stuff.

[add heywood]

I like the gauges look, my car has loads (full Defi range)... If I was to do it all again I would get the Syvecs, the threads I have read on here about them have all been positive. The features it has, such as limiting rpm/boost until optimal oil temp, traction control really are great.

 

Pm Hodge on here... He has changed the rod bolts but is running a standard bottom end, and I'm sure he is running 800/900 bhp!

 

I'm running standard bottom with tuned head. I got around 740 fwhp and was told not to push over 7500 rpm by my tuner.

[Ricardod]

Very usefull info here, thanks people.

I currently have an oil temp oil pressure and boost pressure gauge.

Also had a working Innovate Lc1 but it took a c**p on me.

[caseys]

I have gauges and Syvecs, when I had my fuel injector problem it was the AFR gauge that made me realise I running really rich then randomly really lean not the ecu.

 

 

But to follow that logic, either can give a false positive - I've had gauges which misread, which make you worried.

 

What's needed (imho) is a happy medium driven by the ECU - have it that you can have say, a warning threshold on water temp so if it exceeds it x times within a given interval you get the EML and a limp-mode, if you hit the next threshold you get engine cut. I agree, gauges can give you a nice context, but again, unless you have something light up like a christmas tree, gauges just distract you in everday usage.

 

This only comes from my experience of monitoring performance of large estates of equipment (not cars) - it's fine having gauges and statistics coming out of your ears - unless you have a decent metric to measure against, or some automation to react then measuring any given value manually is not infallible. Heck, most logging data in the syvecs is more than we ever need, it's useful for diagnosis post-event for sure though - I'm hoping to get Scal up and running and read it a little bit.

 

The features it has, such as limiting rpm/boost until optimal oil temp, traction control really are great.

 

I'm going to do a nice thread writeup soon I'm now not sure what's more addictive a sound in my car - the wastegates/screamers, or the lovely TC sound that the Syvecs makes It's a la F1 TC.... lovely.

[SimonB]

Just to clarify the reason to buy bigger brakes as caseys et al were saying - and I apologise in advance for getting quite technical here but you already understand anyway - you need an increased rate of deceleration to the ABS actuation limit, as acceleration is the square of velocity, (or should that be the other way round? Probably not atall!), so the same goes for deceleration, that is, twice the speed requires four times the energy dissipation, so in other words, there is much more momentum in the car for what is only a little more speed and it's momentum that needs to be reduced, since you can slow down to say, 40 but still be carrying much more momentum than the guy next to you who braked earlier (or stronger) and can accelerate out of a corner, for example, while you struggle to stay on the track at the same speed leading in.

 

Think of momentum as another smaller car inside yours, where everything is fine as long as you're both going the same speed but yours is the only one with brakes, (hence the invention of seatbelts), so even as you brake, there's still a separate force pushing you along that needs to be tamed.

 

The faster you accelerate, the quicker the car builds momentum, which is what might catch you out if you're not careful and bigger brakes kill momentum much quicker than small ones. I know you said you'd not use the car on a track but if you did, you could brake later and keep more momentum going through a corner under control, thus giving you the winning advantage.

 

Besides, I have some 356mm D2 8 pots for sale!

 

 

This is a bit confused although the principle is sound! Firstly, acceleration is the rate of change of velocity, nothing to do with squaring. Momentum is velocity times mass. So if you assume your mass stays the same your momentum depends only on speed, nothing to do with acceleration or decelleration. If you are going twice as fast, you have twice as much momentum, not four times. What you mean is kinetic energy, which is the mass times the velocity squared. It's kinetic energy you have to convert to heat energy via your brakes to slow down. The bit about about momentum in a corner is wrong. If two cars (of the same mass) are both going the same speed they will both have the same momentum and kinetic energy no matter what happened before to get them there. The advantage of braking later is simply that you travel faster for longer before you brake, nothing to do with momentum in a corner.

 

In any case, ABS triggers based on wheel slip. The tyres can only provide so much friction so if you try and slow down faster than that they will lock up. If your brakes are strong enough to make that happen then you have reached the limit of your deceleration, and no matter how powerful your brakes are you won't be able to brake any later. So if Jspec brakes could lock the wheels at high speed and keep them locked then the only benefit of bigger brakes would be repeated stops as somebody said already. But I doubt they could in fact, they just can't shed enough heat to get rid of all that kinetic energy when you're going fast! Of course if you don't go any faster with your extra power it makes no difference.

[caseys]

So if Jspec brakes could lock the wheels at high speed and keep them locked then the only benefit of bigger brakes would be repeated stops as somebody said already. But I doubt they could in fact, they just can't shed enough heat to get rid of all that kinetic energy when you're going fast! Of course if you don't go any faster with your extra power it makes no difference.

 

Surely a larger pad surface would mean greater heat (energy) dissipation than a smaller surface at the same pressure as a smaller pad? You have a larger friction surface pressing against the disc. Yes there's the ability of any given brake to overcome the rotating disk's inertia, vs the traction the tires allow for the brakes themselves to be effective, but larger pads, discs and more pistons to provide a more equal application of pressure over surface I thought would affect it too? Admittedly yes, tires and traction are the largest quantity for effective braking.

 

Happy to be corrected if wrong, but as long as it's not a sudden stab at the brakes, I would've thought a larger caliper & pad and higher friction material would give better braking on the same wheel/tire setup.

[Morpheus]

This is a bit confused although the principle is sound! Firstly, acceleration is the rate of change of velocity, nothing to do with squaring. Momentum is velocity times mass. So if you assume your mass stays the same your momentum depends only on speed, nothing to do with acceleration or decelleration. If you are going twice as fast, you have twice as much momentum, not four times. What you mean is kinetic energy, which is the mass times the velocity squared. It's kinetic energy you have to convert to heat energy via your brakes to slow down. The bit about about momentum in a corner is wrong. If two cars (of the same mass) are both going the same speed they will both have the same momentum and kinetic energy no matter what happened before to get them there. The advantage of braking later is simply that you travel faster for longer before you brake, nothing to do with momentum in a corner.

 

You're probably right. I just remember a series of school physics lessons where we measured the acceleration of a toy 'matchbox' car on a wooden ramp about a foot long so we could time the speed increase per distance and vaguely recall acceleration being a square of velocity. This is why I said (sort of) that the car picks up momentum as a square. Same analogy as braking distances being a square of speed. If you're going twice as fast, you need more than twice the braking distance. We just got reminded of this on my recent speed awareness course when they told us that we'd surely kill someone if we went over the speed limit.

 

There's no doubt in my mind however, that two cars travelling at the same speed at a given point in time can have dramatically different momentia, (if that's even a word), as one can still be overcoming inertia to attain a given speed while the other can be braking to shed momentum. 40 mph for example, is just the snapshot point at which their respective speeds cross, with their stored energy ramping in different directions. This is my point, basically.

 

Imagine braking from 180mph down to zero as fast as you can. The car will still be lurching forward when the front tyres finally stop dead. It then rests back down level as the tyres and suspension absorb the remaining momentum.

 

Now imagine it coasting smoothly to a stop over a much longer distance, say a mile. The car will just appear (and feel) to stop without any forward momentum to speak of because the momentum has been dissipated in line with deceleration. Speed and momentum are two seperate phenomena, the latter causing many back ends to swing out when it isn't killed properly and why you shouldn't brake during a corner but before. You need to kill the car's momentum as it isn't directly proportional to speed. There's a distinct lag time. This is why it's unnerving to drive with someone who brakes too late because you can feel the car's momentum pushing you forward strongly, even at slow speeds, making you doubt that you're going to stop in time.

 

Once scientists understand gravity, they'll be up to speed.

 

Mass for example, is not a constant. Acceleration increases mass, otherwise, standing on a set of bathroom scales, you wouldn't be able to make the weight reading increase by bending your legs quickly then stopping. You've gained mass or energy by moving faster. That's momentum.

Edited December 23, 2011 by Morpheus
pluralised a singular (see edit history)

[pauld36]

getting back to your original question ,i ran approx 550hp through a standard engine for about a year and admittedly quite hard,when the conrod snapped and completely wrecked engine,but scary part was upon dismantling rest of engine found stress cracks on every conrod, piston and bottom ends.

so id be very careful about putting big power through these,unless your going to drive like a little old lady lol

[Morpheus]

If two cars (of the same mass) are both going the same speed they will both have the same momentum and kinetic energy no matter what happened before to get them there.

 

This is the key phrase. They won't have the same mass as they approach the corner if one has less momentum because he braked more.

[Morpheus]

getting back to your original question ,i ran approx 550hp through a standard engine for about a year and admittedly quite hard,when the conrod snapped and completely wrecked engine,but scary part was upon dismantling rest of engine found stress cracks on every conrod, piston and bottom ends.

so id be very careful about putting big power through these,unless your going to drive like a little old lady lol

 

Wow, sounds like you were lucky to get out alive!

[pauld36]

lol not quite that hellraising ,when it actually came through side of block i was only doing about 40 mph it was a bang then a big pile of smoke as oil poured onto exhaust ,just very very expensive

[Morpheus]

lol not quite that hellraising ,when it actually came through side of block i was only doing about 40 mph it was a bang then a big pile of smoke as oil poured onto exhaust ,just very very expensive

 

Was it a snapped rod bolt/stripped thread or snapped rod beam that caused it, do you know? What were the bolts like when you saw them? All the caps in place on the rods or the broken one with bad bolts?

 

When rod bolts snap under high tension just after TDC they allow the rod to get smacked by the crank on it's next revolution, which sends them through the block. It would be helpful if you knew which broke first, that's all.

 

Pics would be awesome too.

[pauld36]

only number 6[the one furthest from front of engine] snapped,the rest just had strees crack everywhere,

[Morpheus]

only number 6[the one furthest from front of engine] snapped,the rest just had strees crack everywhere,

 

Yeah, that got broken from being hit by the crank alright. A cap/bolt must have failed. Any pics of the big end?

[SimonB]

This is the key phrase. They won't have the same mass as they approach the corner if one has less momentum because he braked more.

 

Mass doesn't change. It's basic physics, mass is basically the amount of stuff an object consists of. Your bathroom scales analogy is wrong, the scales increase when you bend your legs because you are exerting a force on the scales in addition to the force gravity is exerting by your mass being attracted to the mass of the earth. Scales don't measure mass directly, they measure the force applied to them. If you stand still that force is just the force of gravity on you, If you press down on the scales that force is measured too - doesn't mean your mass has changed.

 

The thing you're talking about regarding lurching forward is weight and load transfer. Basically the mass of the car wants to carry on moving - because the centre of mass of the car is above road level this tries to rotate the car forwards which puts more load on the front and reduces it on the rear - it exerts a force in the same way as your bathroom scales example. This also makes the suspension compress at the front and expand at the rear and pitches the car forwards. If you decelerate more quickly this force is greater. Nothing to do with brakes or mass.

Edited December 24, 2011 by SimonB (see edit history)

[SimonB]

Surely a larger pad surface would mean greater heat (energy) dissipation than a smaller surface at the same pressure as a smaller pad? You have a larger friction surface pressing against the disc. Yes there's the ability of any given brake to overcome the rotating disk's inertia, vs the traction the tires allow for the brakes themselves to be effective, but larger pads, discs and more pistons to provide a more equal application of pressure over surface I thought would affect it too? Admittedly yes, tires and traction are the largest quantity for effective braking.

 

Happy to be corrected if wrong, but as long as it's not a sudden stab at the brakes, I would've thought a larger caliper & pad and higher friction material would give better braking on the same wheel/tire setup.

 

That's completely correct, it would give better braking. But you can only use that better braking if the wheels are still going round. Once your brakes are slowing you to the point of locking the wheels you can't make use of any more braking effort.

[Morpheus]

Mass doesn't change. It's basic physics, mass is basically the amount of stuff an object consists of. Your bathroom scales analogy is wrong, the scales increase when you bend your legs because you are exerting a force on the scales in addition to the force gravity is exerting by your mass being attracted to the mass of the earth. Scales don't measure mass directly, they measure the force applied to them. If you stand still that force is just the force of gravity on you, If you press down on the scales that force is measured too - doesn't mean your mass has changed.

 

The thing you're talking about regarding lurching forward is weight and load transfer. Basically the mass of the car wants to carry on moving - because the centre of mass of the car is above road level this tries to rotate the car forwards which puts more load on the front and reduces it on the rear - it exerts a force in the same way as your bathroom scales example. This also makes the suspension compress at the front and expand at the rear and pitches the car forwards. If you decelerate more quickly this force is greater. Nothing to do with brakes or mass.

 

Ok, I fully appreciate where you're coming from but how does a constant mass cause an increase in force if Newton's third law of motion stands? If every action has an equal and opposite reaction, you would simply stand up straight on the scales and no increase in weight would be temporarily registered while you were descending, unless that is, mass also increases with velocity or acceleration. This is why I don't get on with my brother who teaches physics for a living because it's all theory that doesn't always reflect reality.

 

I've never forgotten an analogy I heard of a pea, that travelling fast enough, could knock down a house. Energy = mass so increased kinetic energy = increased mass. Something weighs more when it's thrown at you, for example as it has added energy. Objects can store energy until they find a way to release it or until the apple lands on Newton's head as it were. They must therefore increase in mass if energy and mass are interchangeable.

 

This is interesting reading below...... and yes, I'm referring to relativity, (the observer's point of view), rather than whatever 4D physics is. Presumably time exists in relativity so it should be 5D or something? I love physics but I'm too uncomfortable accepting accepted wisdom since it hasn't got us where we will one day inevitably go. This will only happen when we listen to those who claim to know already, as how do we know that they aren't from the future, coming back to tell us what we're doing wrong? Who would believe them without first accepting the possibility of time travel? Quite a problem.

 

http://www.physicsforums.com/showthread.php?t=80727

 

I don't claim to understand the equations for a second but I agree with Garth's logic in post 5. You're more inclined to agree with post three, perhaps? I would ask why you need to subtract the 'boosting energy' as he calls it when it's being stored by the object or moving body and thus increases it's relative mass, however temporarily. Everything in this universe is relative so I'm taking that for granted in everything I say. For the purposes of this discussion, it means the difference in braking force required to stop a speeding car or let it career into a wall. The ABS point is a relevant one, however, as I said, the rate of deceleration before that binding point will slow the car much faster with bigger brakes, which is what counts.

[Ricardod]

What about the fuel system, anny advices on that? Read on supraforums to stay away from walbro's, especially fake ones.

[Morpheus]

What about the fuel system, anny advices on that? Read on supraforums to stay away from walbro's, especially fake ones.

 

I have no experience in this area but if as you say, a single '044' would struggle to fuel 700whp, use two! I'd do a search for best fuel pump and see what you get. The guys with big horsepower will know all about it and back again.

[Luxluc]

I have been running twin walbro's for almost 4 years now. I never had a problem.

 

Stay away from the e-manage ecu : Go for a proper stand alone unit. It's the wisest if you want big bhp.