Gs400 Mileage Mods

[SHYHEIM103]

Hey all,

This is my first post on this forum, my fiance' has a 2000 GS4 and I want to increase mileage and performance. What mods can I do to her car to make it get better mileage? I was thinking headers, exhaust, intake, and reprogramming? But from what I'm noticing about this lexus, stuff's expensive! I don't want to break the bank on this, but just want some advice, also, as far as the exhaust goes, I don't want it loud. TIA

Chris

[sakataj]

welcome to the forum.......i hate to break it to you........but u start adding headers,exhaust,intake, and reprogramming your gonna get EVEN WORSE gas mileage! anytime you start modifiing stuff its gonna directly affect gas mileage! very few if any performance modifications are gonna IMPROVE gas mileage!

"i will welcome myself back to the forum as im woo hooooooooo finally unsuspended! hahaha!"

brian

[SHYHEIM103]

Thanks Brian, and "welcome back, welcome back, welcome baaack" Oh well, that makes me feel better anyway, it's the Mrs. car (I drive it often, I'm gonna pay for it once the magnum gets here... she'll be robbing that from me!) but the mods for this car are expensive anyway, so i'm glad i can keep it stock!

[sakataj]

i really haven't modded mine yet although when i do im looking at a (custom) intercooled supercharger/header/intake/exhaust but i wanna do a supra break upgrade and suspension first.......

i have the 4.3 liter v8 where as u have the 4.0 liter v8 they are essentially the same motor! so most everything will fit! im going for a classy semi stealthy upgrade but yeah your right, most the mods on this are costly!

"i will welcome myself back to the forum as im,woo hooooooooo, finally unsuspended! hahaha!"

brian

[fordsvtmfl]

I have a 98 gs3, and i used to get 16-17.5 mpg (all city) and i have changed my spark plugs, added a K&N cold air intake, and changed my oil from regular castrol to mobil 1 synthetic and now i get 18.5-19.5, which in the long run saves me about a tank per month (used to fill up 1x a week, now about every 10-12 days) ...and thats $60! all said and done...from what i can tell, the biggest change came from the oil. i also recommend using some kind of fuel system cleaner...like stp...that seemed to help

[sakataj]

i have a 2001 i have a k & n air filter and i run FULL synthetic mobil oil and filter! i wouldnt put ANY system cleaner in my car though, mopst of them are just garbage or gimmicks! and you wont see ANY mileage difference from changing your oil!

"i will welcome myself back to the forum as im,woo hooooooooo, finally unsuspended! hahaha!"

brian

[fordsvtmfl]

well, i did, and unless i got some kind of "magic" mobil 1...i dont know what changed it, and from experience..with many different cars, i know that fuel system cleaner works when used properly

[sakataj]

u must have cause oil has no effect on mpg! maybe your driving style changed! i just wouldnt put stuff i refer to as crap into my car! thats just my opinion though

"i will welcome myself back to the forum as im,woo hooooooooo, finally unsuspended! hahaha!"

brian

[fordsvtmfl]

changing your oil CAN affect your mpg IF you change from standard oil to fully synthetic. not just a normal change with the same type of oil...but if you change types it can.

[sakataj]

never had it happen and would have to see data or field testing to believe that! NO REASON it should change, the viscosity of the oil the crank is running through shouldnt be substantial enough that it should matter!

"i will welcome myself back to the forum as im,woo hooooooooo, finally unsuspended! hahaha!"

brian