Mods and Remaps

[xrnman]

Hi, I have just got a 2009 IS 250 C (its nice). I am looking to upgrade the front grill and lights is this possible? Also I am looking at getting it remapped as it is quite a lazy engine has anyone done this please

[Texas]

Not much point in mapping ( if you could!) as it’s non-turbo engine.

[Mr Vlad]

Front grill could be changed to the f sport type. As for headlight upgrade you could go vland. As for remap get a car with a turbo. The is250 is a superb cruiser not a boy racer type car tho when floored it does jolly along quite nicely. 

[Linas.P]

4 hours ago, xrnman said:

Also I am looking at getting it remapped as it is quite a lazy engine has anyone done this please

Not possible to do, there are people who make silly claims, but the fact is - you can't get more power from naturally aspirated engine without hardware mods. And when it comes to IS250 mods there isn't much you can do - bigger exhaust and ram intake with get you maybe 5hp. The step-up is supercharger - but that will cost like £5000. So with IS250 you get what you get.

As well it is not "lazy" engine, but I suspect you coming from modern turbocharged car expecting massive torque midrange, this is not how naturally aspirated engines works - you need to rev it out all the way, it pretty much only becomes alive at 4000rpm+. And between 4000-7000rpm it is very very lively. As well I would describe engine as "lazy" if it is not responsive, but IS250 is responsive just doesn't have massive torque which pushes you back into seat at just over 2500rpm, which by the way I think is a good thing.

[H3XME]

On 5/13/2022 at 6:23 PM, Linas.P said:

you can't get more power from naturally aspirated engine without hardware mods. And when it comes to IS250 mods there isn't much you can do - bigger exhaust and ram intake with get you maybe 5hp.

This is true. Remap on a modern NA car is 98% time waste of money. We have self learning ECUs etc. There isn't anything they can do in terms of fuel/air adjustment without changing the hardware. If you want power out of NA car then there is only a few options and not all very effective. I know this from tuning a naturally aspirated GT86..

1. bigger throttle body
2. polished intake manifold for arguably a better air flow
3. intake manifold spacers (better torque mid range, but you're worse off at the top end)
4. exhaust system - remove all catalytic converters from your car, and then you can go for a remap and see real gains. Cat-back exhaust on it's own doesn't do much at all.
5. aggressive air intake ("performance" air filter is nothing noticeable on its own)

That's about it. No point adjusting fuel because you will not be able to force enough air into the engine to justify increasing fuel flow.

Full cat-less system (headers and secondaries) and air intake will give you max. 15% increase after a remap. And at this point we're closer to £1500 for all of that. Just so your IS250 can potentially make ~230hp. Increase of 20odd hp is noticeable if you only have 200 to begin with, but 10 isn't. And you will get 10 after the right exhaust and the right air intake..and what is the right exhaust and air intake? Who knows. It's an IS250.. a platform that hasn't really been defiled by people who modify cars..yet. 

I would say, the only thing a remap can do without touching the hardware is better throttle response. That is generally electronically controlled, you can feel the difference if you switch to PWR in your auto IS250 - manuals don't have this button, so we essentially drive in "PWR" all the time. Something that is quite common on Nissans, especially 350/370Z is the fact that WOT isn't actually 100% opened until 4th gear. In 1st, 2nd and 3rd gear, the throttle body opens to ~80%. 4th, 5th & 6th gear it's 100% open on WOT (wide open throttle). So with an ECU remap, you can unlock this and get 100% power in all gears.. but I'm not sure if this is the case on Lexus cars. 

[Linas.P]

One way to get more HP in NA engine is to increase rev limiter, but that literally means destroying the engine and it is not very usable as that extra power only comes at the top end. So this is more for racing or just dyno graph. What is that higher RPM? maybe 7500, maybe 8000 if lucky, but beyond that definitely results in blown engine. And to do it even remotely "property" it would be ideal to get forged cranks, pistons and ideally dry sump... and all specialised rings, bearings ect, which I don't even know if they are available for 4GR-FSE or they would have to be custom ordered (imagine the price of that). Again for racing that has been done (on other cars), but realistically it is neither cheap, nor good for an engine, nor really beneficial in every day driving. 

[eleveneleven]

I'll echo everyone else when it comes to engine mods, not much that can be done by the looks of it unless you're willing to spend some cash. It's a pretty quick car though when pushed especially with the PWR button activated. 

As for cosmetic mods there's plenty that can be done on both the interior and exterior. 

@ahmed24 has a great little blog with some very cool 250 upgrades https://is-250.blogspot.com/ 

[H3XME]

1 hour ago, eleveneleven said:

I'll echo everyone else when it comes to engine mods, not much that can be done by the looks of it unless you're willing to spend some cash. It's a pretty quick car though when pushed especially with the PWR button activated. 

As for cosmetic mods there's plenty that can be done on both the interior and exterior. 

@ahmed24 has a great little blog with some very cool 250 upgrades https://is-250.blogspot.com/ 

if one's chasing power, they chose the wrong trim level.. You can install an RR Racing supercharger that will get you to 320+ hp for £6k, but if you have 6k to spare, might as well sell the 250 and get an IS350 from Japan for ~£8000... it's got an overall better engine and you'll have the 320hp without a supercharger. Of course things get tricky if you want a manual.. then you will need the supercharged 250. Or just get a 350Z/370Z if you don't need the extra doors. 

[H3XME]

Going back to this thread. I am going for dyno testing on 3rd September. (Yay, can't wait to get disappointed by the numbers). I'll report back with how much power my car makes. I'll be surprised to even see the official figure of 208bhp.

[Mr Vlad]

Fill up with super unleaded and add Millers Oils petrol eco max octane booster. As tesco say every little helps.

[H3XME]

9 minutes ago, Mr Vlad said:

Fill up with super unleaded and add Millers Oils petrol eco max octane booster. As tesco say every little helps.

Super Unleaded, yes. No to the additive though, it wouldn't be an accurate figure as 1) who knows if it'd make a difference 2) I wouldn't normally use it so even if it worked I wouldn't be driving with that in the tank all the time, so whatever power increase it could cause, I wouldn't have it on a normal day.

[Mr Vlad]

I've been using the additive for over 20 years on every car I've had. In diesel it makes a noticeable difference. In petrol not quite as much. Drive ability and fuel economy benefits. 

[H3XME]

7 minutes ago, Mr Vlad said:

I've been using the additive for over 20 years on every car I've had. In diesel it makes a noticeable difference. In petrol not quite as much. Drive ability and fuel economy benefits. 

I worked for LIQUI MOLY. Oil & Additives manufacturer. Additives made very little difference and it really depends on when you start putting them in the car. If it's too late, they won't make any difference. They're more so a preventative treatment in most cases rather than a magical fix. I used their fuel additives before, it was meant to flush the injectors should there be any gunk - I couldn't tell a difference. Tried an octane booster too, I'm sure the fuel burnt better but I wouldn't say it made a difference on the lexus.. turbo charged cars maybe respond better to it. 

[J Henderson]

2 hours ago, H3XME said:

I'll report back with how much power my car makes. I'll be surprised to even see the official figure of 208bhp.

204hp isn't it?. Not sure where that 208hp figure comes from (JDM?), but you always see that variant when searching for parts.