Deposit Paid, Last Min Nerves

[ashyk36]

Hi all,

Have put down a deposit on an IS250 and will purchase the car fully if a few bumper issues are sorted out by the bodyshop by the seller.

I really like the car but I naturally I have a few niggles in mind. I hope somebody can put them to bed:

1. I was expecting a bit more of an oomph in terms of sound from the V6. I dont want something too loud but enough to get the pleasure from a heavy right foot every now and then. On my 350z I installed high flow cats which increased the noise volume slightly but gave it more of a roar sound. Is this something that can be done on the IS? I dont really like the sound of an aftermarket exhaust.

2. Most the MPG threads seem to have 'good' values or mixed motorway driving. I literally drive 16 miles through the ciy day in day out, would I still see 24 mpg driving carefully?

Thanks

[jackcramerr]

24mpg yes. I like how is250 is quiet. I don't like after market exhaust. I have read on this forms that if one upgrades the intake pipe to ISF one, it makes is250.roar.

[jamesm182]

Yes low to mid 20's town driving. Motorway you can easily see 35+ and I've even had 42 on really long drives.

[madasahatter]

I get around 22 town driving .

[rayaans]

Takeda intake for the IS250 sounds great

[mk_lon]

I have a 07 IS250 and I live in London, when I drive like a granny I get 22mpg, if I put my foot down that drops to 19mpg. On the a406/motorway I have got up to 38mpg.

I recently tried to address this with engine cleaning chemicals (on the advice of my mechanic) and using shell v power for a few weeks. Whilst the smoothness in ride and engine response improved significantly there was no real difference in mpg...

[toffee_pie]

them additives are not going to give improved mpg, they 'might' clean out internals and keep the Lexus purring smoothly but will hardly increase mpg.

I drove 1,100 miles to Ireland just recently, computer read average 34.3 MPG.

As for the noise, put on a CAI, or Typhoon intake. That does make a noise above 4k rpm....

[Brechin Slate]

I bought my 2007 IS250 just before Christmas and haven't regretted it for a second. I now enjoy the quiet and refinement so I'm not that bothered about the exhaust note, I guess I got that out of my system with previous classics or maybe I'm just getting old and boring.

There isn't much traffic where I live and most of the roads have 40 mph limits so I'm getting between 32 and 34 mpg locally. It drops down pretty quickly if I only do short journeys of 1-2 miles.

I managed 50 mpg on a run from Portsmouth to New Milton, mostly motorway and clear roads, cruise control for 80% of the journey and didn't go above 60 mph. However that was a test to see what I could squeeze out of it as a best case scenario.

I reset my ECU a couple of days ago and wait to see if that has made any difference but in the meantime forget those last minute nerves, it is a superb car.

[ashyk36]

Nice. And in terms of the seats in the fsports, do they wear out quicker than others?

I say this because my brother had a Clio sport which had very similar material on the seats and his wore out pretty quickly

[agent_dess]

Cut out a a slightly larger than credit card size rectangle from the intake box so that it mimics the fsport intake box... Guarantee u the extra grumble above 3k rpm :)

Everyone loves the noise from my car, best part it doesn't cost any extra and fairly easy to do.

[steveledzep]

Cut out a a slightly larger than credit card size rectangle from the intake box so that it mimics the fsport intake box... Guarantee u the extra grumble above 3k rpm :)

Everyone loves the noise from my car, best part it doesn't cost any extra and fairly easy to do.

Any photos ?

[ashyk36]

Cut out a a slightly larger than credit card size rectangle from the intake box so that it mimics the fsport intake box... Guarantee u the extra grumble above 3k rpm :)

Everyone loves the noise from my car, best part it doesn't cost any extra and fairly easy to do.

Any photos ?

Any posts on this? This solution would be great as everything would then remain stock. But wouldn't dirt be able to access easier?

[johnatg]

Wouldn't just taking the inlet duct off do the same job? Presumably we're talking about a hole before (ie below) the filter? Taking the duct off would leave a medium sized hole - bigger than a credit card but not huge and I guess you'd get more noise. Doubt you'd get more performance. Haven't tried it, but the duct just comes off with one bolt and a trim clip, and you wouldn't be cutting anything - could just be returned to stock - when you get fed up of the noise! :-)

It would lower the inlet point though, so watch out for floods, but then the inlet duct joint to the air box is hardly air (or water) tight.

[toffee_pie]

You wont ever get tired of the sound from this, its not a big expense and makes a big difference.

[agent_dess]

Sorry never took, but quick search in the forum or Google will show u how to do it. But if I do any cleaning under the hood I'll try grab some photos.
Yep no performance increase but you get the growl which is all I wanted :) no it doesn't get any dirtier, your just adding another hole which places it behind the headlight just like on f-sport in take box. I recommend this if u want sound upgrade without any extra cost or having to declare mods to insurance.

**UPDATE: found the one with a quick google search... on the left is the f-sport box - on the right is the standard box, you can compare and see which hole you need cut out.

[jackcramerr]

I wonder if F SPORT can be fitted to IS250 SEL

[johnatg]

Yes it can - but really - why? It's a fair old cost for what you can do for free.

[agent_dess]

I had originally placed an order for the joe-z intake pipe, but then read on US forums that alot of'people.were just modding the intake box.. So I thought I would give it a try, once done i was so impressed with the results that I canceled the intake pipe order... My little kids love the noise the car makes, best thing is that car is quiet when u need it to be and a beast when u hit 3-4k rpm :)

Mod the intake box u will not regret it :)

[ashyk36]

I had originally placed an order for the joe-z intake pipe, but then read on US forums that alot of'people.were just modding the intake box.. So I thought I would give it a try, once done i was so impressed with the results that I canceled the intake pipe order... My little kids love the noise the car makes, best thing is that car is quiet when u need it to be and a beast when u hit 3-4k rpm :)

Mod the intake box u will not regret it :)

Did you also remove the fins or did you only go for the cut out? Did you use a jigsaw to cut out the hole in the plastic?

[ashyk36]

Also when removing the intake box, do I also need to remove the pipe or will the box itself just come out?

[agent_dess]

You will need to remove the intake box from the car, so yes you will have to disconnect the pipe.

I worked out and marked the area i wanted to cut out, drilled a hole using in drill in one corner and used that pilot hole to start cutting the rectangle with a jigsaw..

But bear in mind the intake box slopes so it will not be a straight forward cut.

Others have used a dremel but i never had access to one.

Finally file down the rectangle and the fins to make it smooth as possible.

[johnatg]

It's certainly easier if you remove the (inlet) pipe first - only held with one bolt and a trim clip. I'd take the car for a drive after you've done that and see how it sounds before you start cutting!

[jackcramerr]

John the inlet pipe you refer to, is it before the filter ? What is the purpose of it originally ?

[johnatg]

It's a sort of snorkel type intake to the bottom of the airbox - ie before the filter. If you look at Eric's pic on page 1 above, it's the big plastic thing in front of the engine with an oval intake hole. (You can see the bolt and trim clip securing it). It leads to the bigger square hole in the airbox you can see in the airbox pictures.

I'm not sure why Eric kept it - it won't be connected to anything now his airbox has presumably been removed to enable the Typhoon system to be fitted. (Or can I see the bottom half of the airbox still there, with the Typhoon filter sitting in mid air more or less in it?) Maybe he reckons it ducts some coolish air in to the general area of the filter. Maybe it does. Does that make any difference to performance? Maybe. Maybe not. (Cooler air is in theory a good thing - you get more mass of air than if it's hot so more fuel air mixture inducted into the engine).

It's original purpose? To duct cooler air in than that otherwise available in the airbox area (totally negated as far as I can see by cutting the extra F-Sport hole) and to silence the intake - again negated by cutting the hole, but if noise is what you want.....

PS - Lexus engineers would also no doubt claim some benefit from tuning the length of the inlet tract for optimising inlet air pressure waves - without going into the physics you can theoretically increase torque, at least at certain specific revs, by getting the inlet tract length, shape and volume just right. Again, the inlet duct obviously plays a part in that and the effect, small though it will be, will be negated by cutting the F-Sport hole.

[Verbout]

A concern to me with Eric's car is that it is sucking in hot air from within the engine bay. Hot air is less dense and therefore has less oxygen.

That is why the air scoop is placed to the front of the car to facilitate cold dense air for a better burn.

And as John touches on, the air intake is tuned so the pulse from the combustion process are in synch.