Shahpor
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Posts posted by Shahpor
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Seems to work just fine 🙂
Harry's garage also released their video of the same car today:
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This is somewhat confusing to me, I must say.
As Miles has pointed out, I was a part of said thread and I didn't think there was anything in there that Miles did wrong per se. At least, not enough to justify what sanctions are being apparently applied here. I also find it strange that no reply has been received that at least explains the reasoning behind what has happened. perhaps something has been missed along the way?
In all my dealings with Mods/Admins here, I have always found them fair and understanding, and in fact, I think a little too hands off sometimes!
Either way, I hope the situation gets resolved as soon as possible and any disagreements settled.
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I'm surprised by how shocked I am by this news..
Like many of you, I had come to know John as a very friendly, helpful character on here and it just won't be the same without him.
A prolific contributor, always ready with a great reply, and a reassuring presence.
RIP 😞
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35 minutes ago, hockeyedwards said:
@Shahpor good to see your system is up and running, the glory months are just around the corner!
After install last year, September ran 90% off grid, winter months have been 'tough' and due to sub optimal roof position and lack of sun, was pretty much reliant on overnight charge, but still better than running from the grid for the day! Plus the government grant was pretty much covering my expenditure. Recent weeks have seen 6kw+ being generated, so more to come in sunnier months!
I have set up the Eddi to force discharge power from the battery in the morning and evening to heat the hot water, regardless of surplus from the panels. Heating will soon be completely off and will be much less reliant on grid charge overnight. Small bills here we come!
Enjoy watching your apps like a hawk haha!
Thanks Kieran,
Yep, already watching the apps on an hourly basis 🙂
Still trying to fine tune the Battery charging, but apart from that, it is working well. I am charging it too much overnight at the moment, so it is already full for the day. I will modify my charging profile tonight to reduce it down even further. In a month or so, it will stop the overnight charge altogether and we should be 100% solar powered for the incoming summer months!
Terrible performance over the weekend, but yesterday was much better: managed 14.5 kWh generated as opposed to 12.9 consumed 🙂
Don't have our solar water heater installed yet either, so a little more work to be done yet, but you are correct that it is definitely a good time of year to get it setup! Definitely looking forward to seeing my electric bills for the coming months.
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The technology of the panels has come a long way, which is reflected in the price - roughly £150 per panel now!
I also think that the biggest game changer with these systems in the inclusion of a Battery. It adds massively to the efficiency as, for example, I am currently running from my Battery that was charged during the day. This means that in the coming months I will be able to run my house on solar generated power 24 x 7.
The cost of the battery's is a bit of an issue at the moment, but hopefully they will go the same way as the panels have in the near future.
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Hey all,
Time for an update. Finally got the system installed on Thursday! 🥳
So far, so good. Solar Water Heater is still on backorder, but the rest is done. A couple of small hiccups along the way, but nothing major and Daniel from Kembla has been great throughout, so definitely recommended.
Still haven't ironed out a few setup quirks, the biggest one being that you can't stop the house Battery from being drained if you charge your EV via the Zappi. I think there might be a way where you 'turn off' the house Battery and use just the grid, but I haven't had a chance to test that yet.
With the weather being what it is, solar production hasn't been great, but it is still a novelty to see the house not consuming grid power for most of the day 🙂
Our panel layout turned out like this in the end:
With North being straight up, you can see that we actually have 3 panels facing north east, which despite not technically being recommended, still seem to put out a reasonable amount of power. This, again, came down to the great installers we had as it was their suggestion on the day once they had seen our roof that it would work in our case.
Oh, and if anyone is considering a SolarEdge setup, I have found Anthony Dyer's videos invaluable, especially when it came time to setup storage profiles:
https://www.youtube.com/@anthonydyer3939
Can't wait to watch the numbers like a hawk in the coming months now 🙂
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3 hours ago, Mr Vlad said:
And after reading/watching some articles that home chargers run on a special rate night rate. But the actual time in hours of the reduced rate is only 4 hours. Ooooop because of the cheaper rate the rest of the 20 hours the cost of the electricity has gone up ! Those with home chargers and a night time special rate please confirm or correct me please.
My EV is being charged as I type this on the cheaper rate.
We are on the Octopus Go tariff, which means 12p per kWh between 0:30 - 4:30 every night, with the rate being 43p per kWh at all other times.
It does make it very cheap the 'fill' the car up as long as you are happy to charge it at these times.
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On 2/28/2023 at 9:35 AM, flotsam said:
Articles are claiming hydrogen is difficult to transport and store. HOW?
On 2/28/2023 at 11:02 AM, Shahpor said:This site explains it well:
"Hydrogen is difficult to store due to its low volumetric energy density. It is the lightest of and simplest of all elements, being lighter than helium, and so is easily lost into the atmosphere.
Another challenge is the very low boiling point of liquid hydrogen (−252.8°C), which means that it needs to be kept cryogenically stored at low temperatures. Storing hydrogen as a gas also has its challenges as it typically requires the use of high pressure tanks (350-700 bar or 5000-10,000 psi)."
"However, there are still hazards related to hydrogen that mean additional engineering controls need to be put in place to ensure its safe use. With a lower ignition energy than petrol or natural gas, hydrogen has a wide range of flammable concentrations in the air meaning that ventilation and leak detection are important for hydrogen systems. Special flame detector are also required as hydrogen burns with a near-invisible flame. Material selection for hydrogen systems is also important as some metals become brittle when exposed to hydrogen."
So, as you can see, some difficult engineering challenges need to be overcome before hydrogen becomes commonplace in forecourts.
On 3/3/2023 at 3:50 PM, flotsam said:That's not true.
The Rough storage facility, Britain's largest doesn't store natural gas as super-cooled, LNG and was recently considered for storing hydrogen.
49 minutes ago, flotsam said:Huh?
Where did I say Rough could be used "as is"? I stated it was being considered for hydrogen which is all that your own links also state. The point I was making was that natural gas is stored there without being super-cooled.
I mean, do you enter a bar and five minutes later people start crashing through the windows because you've started a brawl?
The Rough facility is just an undersea cavern. There is nothing they can do to change it that would make it more suitable for hydrogen. I'm not an expert but I'm guessing that at most only the faciiities used in pumping the hydrogen into Rough would have to be altered.
The bottom line is that if everyone adopted battery-powered cars the grid would undergo a melt-down.
Hydrogen CAN and WILL be stored and transported at a third of the cost of transporting electricity over the grid. The gas-grid can be modified to transport hydrogen, presumably in un-compressed (or not very) and un-cooled form.
Apologies if I got the wrong impression, but I am just going by what was quoted above.
You said you didn't know how storing Hydrogen was difficult, I posted a site that claimed to explain why, you said that wasn't true and then brought up Rough in the same post. Perhaps you didn't mean 'as is', so a bad choice of words on my part, but the inference is that it isn't difficult to store hydrogen because Rough proves it? Again, this is my interpretation, but I hope it makes sense at least.
As for entering and bar and staring a brawl, I kid you not, I did find that funny as I was thinking the same thing about you 🙂 You have very strong views and aren't afraid to share them...
Having said that, I do hope you are right as I would happily buy a hydrogen powered car to replace my Stinger when the time comes.
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5 minutes ago, Love my IS220D but... said:
Hi chaps, thanks for the responses.
Must admit it didn't cross my mind that I don't have a 5th injector - I've read quite a lot about them on IS220D's so they must be quite common I guess, but maybe not on every car, which seems odd.
I had really serious running problems / smoking when all this started, which was helped by cleaning the EGR valve - at the time I really thought this might sort it completely, but the MPG was still down, and the fuel smell / smoking didn't go away entirely (though at least the car would drive).
I've had a Toyota specialist guy plug his machine in a while back and he said all the injectors looked fine, but when I spoke to him last week he admitted he was only looking that the four main injectors. Would one of these machines (I guess that's what a techstream is?) tell me if the fifth injector is at fault (and if I even have one, for that matter!).
Thanks againIan
Hi Ian,
Assuming for the moment that you do have one, then the Toyota specialist should be able to diagnose it as a problem if it indeed the case. They should certainly be using TechStream, which is software that can run on any PC's with the right cable.
As far as I am aware, there is only one test that can be run on the injector itself, which is:
This does require removing it from the car though, so considering the cost of replacement (e.g. https://www.ebay.co.uk/itm/232810780762), it might be worthwhile just changing it whilst its out.
Best of luck.
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16 minutes ago, Miles Simmons said:
Yeah Shahpor
It should have been located on the fuel rail by the fourth cylinder. But it simply wasn't there 🤷🏽♂️
Apologies for being pedantic, but the 5th injector isn't actually on the fuel rail. As per the picture I posted, it is located on the back of the head and has its own separate fuel feed.
So, with that being said, are you sure you don't have one? 🙂
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3 hours ago, Miles Simmons said:
Hi there
Sorry to hear of your issues. Are you 100% sure that your car has the fifth injector? I too have a 2006 Lexus IS 220D and mine doesn't have the fifth injector.
All the best
Miles
Hi Miles,
Are you sure about this? As far as I am aware, all IS220d's had a 5th injector. It should be located here:
As for the original post, I don't believe there is or was a recall for the 5th injector, so a replacement might be the only option I'm afraid.
It might be unrelated, but have you tried cleaning the EGR valve? There is a video of how to do so in the thread you posted. Failing that, you would need a copy of TechStream to really help diagnose the issue if a new injector doesn't work.
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3 hours ago, 08ISF said:
Oops, didn't mean to start an argument. My comments were based on my own experience working as an engineer on British Gas' transmission system for 16 years. LNG has been stored for years in liquid form at various sites around the country but the characteristics of H2 are different. However the principles are the same. Rough was used to store natural gas for a number of years until some bright spark decided we didn't need to store any gas we could get all we needed from others(!!). As you point out Rough is not yet suitable for H2 but it is encouraging that Centrica believe in H2 and are putting their (considerable amount of) money where their mouth is. I think it unlikely that they will try and store H2 cryogenically in the Rough field which is vast (31 billion cubic metres I understand). If they did we might have icebergs in the North Sea. More likely they will store in gas form at some pressure which is deemed to not allow too much to leak.
There is conflicting information on the internet about H2 and not all of it comes from trustworthy sources, some if which is conflicting. In a trawl to find out how much electricity is required to generate 1kg of H2. I had answers ranging from 1.55kWh to 50kWh! Which is correct?? Who are we to believe? Often facts are quoted out of context to prove what ever the author is trying to prove.
And this is the layman's problem. One faction is saying H2 is the way to go and one is saying no go electricity. The volume of noise for electricity is greater than that for H2 so people will not buy H2 cars which makes them expensive (£60k ish) due to low volume and suppliers will not install H2 filling stations due to low demand so people will not buy H2 cars because there are few filling stations. Chicken and egg!
I happen to believe that H2 is worth pursuing to a greater extent than it is at present for reasons I've already outlined. We just need to convince the invertebrates in Westminster. BMW , Toyota and Centrica are obviously onboard to some extent.
I actually didn't want my post to sounds argumentative as that wasn't my intention at all, but from Vlad's reaction, I may have failed 🙂
Thanks Graham, that makes perfect sense. I suppose when considering others' opinions on here the one thing that doesn't occur is that they may actual work in the field being discussed! The notion of 'keyboard warriors' is strong on Internet forums.
Having said that, reading back on our respective comments, it does look like are in agreement on most aspects, it is just the costs implications where we differ slightly, which could very well be me being too cynical 🙂
Appreciate the info on Rough as well - Interesting stuff.
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22 minutes ago, Mr Vlad said:
Blimey Shahpor please don't get you underpants in a twist. How can I put it. Hydrogen has been stored for years all over the place. There are experts here there and everywhere sprouting their 2 penneth worth. Only a fraction of experts are genuine and only come out when angered by the others who are paid by competitors.
Thanks to the Internet there are OMG numerous experts spouting their knowledge. Where that knowledge comes from who knows.
The problem is there are too many 'experts' that the true explanations are not heard.
This thread is about the difference in cost to run an ICE car and an EV.
I went to Leeds today and I drove my is250 like I stole it. Uck my tin hat I averaged 27mpg. Did it in under 25 minutes. How that equates to in kwh per mile I dont know but I bet no EV could match my journey today.
Oh dear, did I do a Linas? 🙂 (sorry Linas!)
To be honest, the actual topic at hand wasn't even the point of my post - it could have been about anything. It is simply that it is difficult to have any meaningful discussions if everything that is said is just deflected constantly, which is what my last two posts were related to.
I really hope it doesn't come across as a personal attack or some such and I am more than happy to be proven wrong if that turns out to be the case.
As for mpg, a steady cruise of 70mph for a roughly 300 mile round trip netted me a whole 32mpg for my Stinger. Still, better than the 12mpg I managed a few days earlier 🙂
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6 hours ago, 08ISF said:
Not easy, but they've been doing something similar with LNG for many years. The LNG we import comes in liquid form by boat and is unloaded into storage tanks that are kept at a similar temperature. Mature technology.
I don't mean to be critical Graham, but why is it that whenever I have made a simple statement in this thread - backed up by facts - someone goes on a tangent trying to get around what I said? Bearing in mind what you are referring to in your post is my answer to another point raised trying to suggest that the Rough installation somehow disproves what I posted?
Your example is easiest for me to highlight: Can you please tell us where you got this information from? I did a quick Google search to see if what you say is accurate and found the following:
Some exerts for those that don't want to read it all:
"The bad news is that while your shipboard or bunkering design might look very similar, the components, like valves, hoses and piping are not necessarily interchangeable: “It’s a smaller molecule and it can escape through joints or seals that would retain LNG,” he adds. “You’d have to look to see if the current components would be suitable – but most likely I think you’ll have changes in your equipment,” says Dr Wuersig. And, he adds, it’ll work out quite a bit more pricey."
"Dr Wuersig explains that the normal 40cm LNG insulation “just won’t work”. He says a moderately large LNG tank could lose 0.2% of its total volume a day but “store hydrogen in the same kind of tank and you would actually lose 5% of the contents every day to vaporisation”."
"Dr Pratt says when it comes to bunkering, “the biggest difference is the much colder temperature of LH2” and explains that unlike LNG, H2 is actually colder than oxygen or nitrogen. While LNG can hover at -163°C, liquid hydrogen needs to be kept at -253°C."
Now, I don't want to beleaguer others by going on and on about this, so I hope this does the trick, but for the record, all I am (and have been) saying is that it is commercially difficult to store and distribute hydrogen as a fuel source for cars. The technology to do so can be developed or, indeed, is already available, but the cost of such a venture is what I believe is putting manufacturer off being one of the first to embrace hydrogen as a car's power source.
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2 hours ago, Mr Vlad said:
Interesting articles Shahpor. One wonders then about the current gas storage containers could actually store hydrogen. I only know what I've seen on TV and YouTube.
On YouTube I saw a video, which I've posted, from America showing how long does it take to fill up a hydrogen car. The station looked like an ordinary fuel station except for the addition of another building. That building was described as a mini factory. It was the storage tank with a cooling system.
On TV just this week Guy Martins programme on where does our electricity come from. Up in Orkney where they are cutting edge in wave energy and they have wind turbines too. Together those two systems produce Too much electricity for the habitants so they're using the excess to make hydrogen. The storage tanks and delivery tanks looked just like what one would expect gasses to be stored in.
Oh and the chances are most of us have seen those cylinder transporters. Some of those cylinders have hydrogen and have had for decades.
The only thing that I can see needs to be done as those companies have inferred is to attach a cooling system.
As stated in the original link I posted, none of these issues are insurmountable, it is just a question of cost. I'm sure keeping something at a temperature of below -252C isn't straightforward!
The same goes for maintaining a tank at up to 10,000psi for years at a time.
So, as I am sure you can imagine, it wouldn't be a cheap endeavour to convert all those forecourts and production facilities to include either new cryogenic plants or replacement of all their store tanks and associated systems.
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On 2/28/2023 at 11:02 AM, Shahpor said:
This site explains it well:
"Hydrogen is difficult to store due to its low volumetric energy density. It is the lightest of and simplest of all elements, being lighter than helium, and so is easily lost into the atmosphere.
Another challenge is the very low boiling point of liquid hydrogen (−252.8°C), which means that it needs to be kept cryogenically stored at low temperatures. Storing hydrogen as a gas also has its challenges as it typically requires the use of high pressure tanks (350-700 bar or 5000-10,000 psi)."
"However, there are still hazards related to hydrogen that mean additional engineering controls need to be put in place to ensure its safe use. With a lower ignition energy than petrol or natural gas, hydrogen has a wide range of flammable concentrations in the air meaning that ventilation and leak detection are important for hydrogen systems. Special flame detector are also required as hydrogen burns with a near-invisible flame. Material selection for hydrogen systems is also important as some metals become brittle when exposed to hydrogen."
So, as you can see, some difficult engineering challenges need to be overcome before hydrogen becomes commonplace in forecourts.
6 hours ago, flotsam said:That's not true.
The Rough storage facility, Britain's largest doesn't store natural gas as super-cooled, LNG and was recently considered for storing hydrogen.
It appears that you are suggesting that the same facility that is currently used for other gases can be used to store hydrogen as is? If so, that's an 'interesting' statement. I presume you read that somewhere, so I don't suppose you could say where please?
From Centrica's own site (they own Rough):
"Centrica is advancing plans to convert its Rough offshore gas storage facility for hydrogen storage as part of its transition to a net zero future."
https://www.centrica.com/media-centre/news/2022/centrica-re-opens-rough-storage-facility/
"Centrica’s long-term aim is to turn the Rough gas field into the largest long duration energy storage facility in Europe, capable of storing both natural gas and hydrogen."
Neither of these claim that Rough is ready to store Hydrogen or that it can do so in its current state.
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1 hour ago, flotsam said:
Articles are claiming hydrogen is difficult to transport and store. HOW?
This site explains it well:
"Hydrogen is difficult to store due to its low volumetric energy density. It is the lightest of and simplest of all elements, being lighter than helium, and so is easily lost into the atmosphere.
Another challenge is the very low boiling point of liquid hydrogen (−252.8°C), which means that it needs to be kept cryogenically stored at low temperatures. Storing hydrogen as a gas also has its challenges as it typically requires the use of high pressure tanks (350-700 bar or 5000-10,000 psi)."
"However, there are still hazards related to hydrogen that mean additional engineering controls need to be put in place to ensure its safe use. With a lower ignition energy than petrol or natural gas, hydrogen has a wide range of flammable concentrations in the air meaning that ventilation and leak detection are important for hydrogen systems. Special flame detector are also required as hydrogen burns with a near-invisible flame. Material selection for hydrogen systems is also important as some metals become brittle when exposed to hydrogen."
So, as you can see, some difficult engineering challenges need to be overcome before hydrogen becomes commonplace in forecourts.
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That's strange.
When I used to go there, a courtesy car was usually available 2 to 3 weeks in advance.
Perhaps they are cutting costs by keeping less cars?
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The same article highlights the biggest problem with hydrogen cars that no one seems to have an answer for:
"Axel Rücker, Program Manager Hydrogen Fuel Cell at the BMW Group, explains:
We have a chicken-and-egg problem with hydrogen propulsion.
“As long as the network of hydrogen filling stations is so thin, the low demand from customers will not enable profitable series production of fuel cell cars. And as long as there are hardly any hydrogen cars on the roads, operators will be reluctant to expand their refuelling network.”"
Personally, I would like to see a dual setup scenario wherein you can buy either a pure electric or hydrogen fuel cell car. This sounds like the best of both worlds and I would have one of each for local and long distance driving.
If only they could get both technologies to operate from the same location (rapid charging and hydrogen refuelling at the same stations), then it can work like petrol and diesel but I just can't see it, at least in the short term.
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That looks like someone has bypassed the EGR altogether.
There are a couple of picture if you scroll down this thread:
Not recommended for emissions reasons, bur supposedly makes the car run better.
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1 hour ago, Linas.P said:
huh?! How did I got involved into that? But as I was summoned I will use this opportunity to put my 2p worth opinion... 😄
Say his name and he shall come... 🙂
1 hour ago, Linas.P said:Yes - many different industries use lithium batteries, but car manufacturing requires ridiculous amounts of it and of the batteries, so lithium consumption is up 5-fold since 2010 and 30-fold since 2000. And yes sure Panasonic, Samsung and Toshiba may be some biggest manufacturers of lithium batteries... FOR CAR INDUSTRY... That Samsung made lithium battery - it does not mean it goes into smartphone. Panasonic is Tesla supplier for example.
I stand corrected. Thanks for the info.
1 hour ago, Linas.P said:As such I always said we should prioritise Lithium for small city cars, no more than 100 miles range, small batteries i.e. use BEVs where they are most beneficial. As far as I am concerned - long-range 200miles+ (or maybe it is better to cap it at the battery size) BEVs should be BANNED, because in my opinion their use does not benefit the environment and they operate in the environment where they have least benefit. Honda E + grant to install charger within London congestion charge zone is great idea, Tesla Model X Long Range Tri-Motor monstrosity in Shropshire is a crime against humanity.
Whilst I agree with the sentiment in general, there are a few specific changes I would suggest perhaps. First, since ranges are extending quite a bit, I think 200 miles is quite stingy 🙂 Encouraging more urban use is certainly a good idea though. As for banning, I think it should be weight and size limited rather than range. Otherwise, you might end up with this monstrosity which weights over 4 tons!
On the subject of lithium ion recycling and 2nd use, this article actually covers the issue well:
As you can see, there is a situation brewing wherein the cost of the raw materials will go up to the point where it is commercial preferable to recycle batteries. There is also the geo-political implications, such as the US not wanting to import these minerals from certain foreign powers. Lastly, scaling up production of recycling/repurposing Battery plants is significantly quicker and easier than a new mining operation, which, according to the above article, takes on average 16.5 years.
So, the question becomes, if it is quicker, easier (practically and politically) and cheaper to reuse/recycle batteries than mine new minerals, why wouldn't you do it? The by-product being that is it helps with the environmental issues as well.
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2 hours ago, Las Palmas said:
This is very beautiful, if it was not from somebody that are very much pro EV cars.
The mentioning of VW part-recycling is as trustworthy as when VW said that diesel cars pollute very little. Or as when they tried to hide it when revealed.
That the black powder is containing the valuable minerals all together mean that somebody competent will have to separate them into useful products. A competent chemist will hardly do it free of charge and who will know how much energy that will use.
All the not really needed materials will be dumped as nobody want to pay for something used if new can be bought cheaper.
I'm sorry but this is a very strange reply to my post.
Firstly, Carwow are interested in selling you cars through their site - In fact, I bought mine via them - and as far as I am aware, aren't pro or con anything in particular.
Second, your view that anything VW says is automatically untrustworthy based on one example is complete nonsense. It also doesn't take into account the very obvious fact that they are building it right now!
https://techcrunch.com/2022/07/07/volkswagen-breaks-ground-on-first-of-six-battery-factories/
As for asking for examples (in your previous post) of current recycling/reusing EV batteries:
https://www.theregister.com/2023/02/08/ev_batteries_solar_storage/
Lastly, you keep going on about how EV batteries are going to be an ecological disaster when the fill up the landfills, but you haven't made mention of the fact that Lithium Ion Battery have been used for decades on all sorts of other applications, so where are all these batteries going?
https://ecotreelithium.co.uk/news/lithium-batteries-uses-and-applications/
As you can see, 14 different industries currently use these batteries with cars being only 1. Also, 3 out of the largest 10 producers of Lithium Ion batteries are using them for personal technology devices (including the phone you are using): Panasonic, Samsung and Toshiba.
Now, I know this is going to come across as a Linas type post (sorry @Linas.P 🙂) but I do feel that your post demonstrates an unwillingness to accept anything that doesn't align with your point of view and is somewhat insulated in its thinking.
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4 hours ago, DavidCM said:
I skimmed through an article on EVs recently,not with any great interest, as if I wanted to drive a milk float,I'd get a job with Express Dairies.
On a more serious note though,has anybody thought about disposal/recycling dead EV battery packs?They weigh hundreds of kg. and the article mentioned that only Lithium salts could be extracted for recycling.Also,the battery packs themselves are large and heavy.What will happen to them?
Apparently solar panels also have a limited life and again have very limited recyclability.Where will they go?
This article gives a good idea of what can be done with used batteries.
https://www.carwow.co.uk/blog/ev-battery-recycling-what-happens-to-dead-batteries
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Budget tyres conclusively bad?
in Lexus General Discussions
Posted
Another thing that I hadn't considered before is would you fit a different tyre based on the performance of the car? Now, I am not talking supercars or anything, but, for example, my Stinger comes with Michelin Pilot Sport 4 S's. Personally, based on how I drive mine, I think the S's are overkill but the manufacturer obviously didn't think so.
When it comes to stopping distances, the performance of the car should be largely irrelevant given the speeds involved, however, when it comes to handling, it is much easier for my rear tyres to lose traction than on my previous cars, so levels of grip might be important.
So, in my instances, I will probably be 'downgrading' my tyres to the Pilot Sport 4's or something similar because the S's seem to be primarily for maximum performance and handling characteristics.