Noob in search of better MPG + some extra "umph"

[endo]

This will be my first Honda, and I know nothing about them. I had a 99 Subaru 2.5RS w/ bolt-ons... but it got into a fight with a truck and lost I drive between 30k and 40k miles per year, so gas mileage, creature comforts, and reliability are all important to me because I'm always in my damn car. So I came to the conclusion that an easy breathing 99EX will be perfect for me.

I was thinking about stage 1 cams, cam gears, intake manifold, throttle body, valve springs, valves, and retainers all from Skunk2 (I figure that if I get it all from the same place at the same time that I could get a discount). A new clutch, light weight flywheel, and header back exhaust are also on the list. I understand that the cost of these parts outweighes the gas savings, but 127chp isn't enough for me... so the price is worth it.

What size throttle body would I need for a setup such as this? I think the stock size is 56mm. What kinda gas mileage could I expect? Does any of this seem like a total waste of money? What would be good for engine management?

Sorry for the long post and the noob questions... I will be digging through the endless number of threads here to try and answer some of my own questions. Tips and and/or constructive criticism is much appreciated. Thanks!

[soul 93]

i dont know if i would do all that....do you wnat it faster or better on gas??....cant really get both

gotta burn more gas to make more power (for hte most part)

[endo]

Originally Posted by soul 93

i dont know if i would do all that....do you wnat it faster or better on gas??....cant really get both

gotta burn more gas to make more power (for hte most part)

I do mostly highway driving and like to drive like a granny and shift around 3 or 4k rpms... but I do enjoy the occasional spirited drive. Because I will be coming from a 2.5RS I will miss the abundance of torque and the boxer rumble... but I only got 25ish MPG with mixed driving (that's why I want a civic). I was hoping that if I invest in parts like a 60mm throttle body, new intake manifold, and header back exhaust to improve air flow that I would achieve better gas mileage + a little extra power for my spirited drives. I will be investing a good bit into the suspension and breakes... but it will never compair to my Impreza.

[soul 93]

those parts will make you flow better...which will lean you out...if you tune to compansate for that you will spray more gas

why not do a lil N2O.....same gas mileage....until oyu wanna sprint

this would also save you about 1k

[endo]

Originally Posted by soul 93

those parts will make you flow better...which will lean you out...if you tune to compansate for that you will spray more gas

why not do a lil N2O.....same gas mileage....until oyu wanna sprint

this would also save you about 1k

LOL, being a noob is frustrating. Perhaps I will just stick with what I know and work the suspension and audio. So if I forget about any of the go fast parts, what can I do to improve gas mileage on a d16y8? Will a 60mm throttle body and intake manifold from Skunk2 do anything for me? Anything and everything will be taken into consideration. On my 2.5RS I bought a throttle body spacer that honestly gave me about 2-3 extra mpg... can I get one for the honda?

Thanks for the help!

[soul 93]

yeah...you can make those upgrades....BUT they are gunna lean you out, which will save you money on gas, BUT the leaner you run the higher the chance you will detonate and eventually need a new motor....

think about it like this...anything that makes you flow air easier will put more o2 in the motor and make you more powerful at the same throttle angle, which will improve gas aswell as give you some horse, but its doing it at the expense of your AFR's..the more things you do without compesating more fuel the higher your AFR will go makeing it more powerful and more dangerous, and better on gas

idk...its on you what you wanna do, but i dont think that an NA build is really what you wanna do

[endo]

Well it sounds like I'm SOL. Maybe I will just kiss vtec goodbye and get a HX coupe

[legacyo13]

Just put on a CAI, intake, header, and exhaust. It'll give you the 2 - 3 more mpg and give you a bit more power, but not much. You could probably do better with a straight pipe, but then again, it's not legal in states with emissions (if you live in one of those states). Where I'm from, they dropped emissions altogether, and since I'm a resident here, I can straight pipe it wherever I want. But a straight pipe is the best way to go for power and better gas mileage.

[98civcEK]

Originally Posted by endo

Well it sounds like I'm SOL. Maybe I will just kiss vtec goodbye and get a HX coupe

hx has vtec-e.......

[speedjunky01]

yea it would lean you out, if you had a carburator( AKA put a toilet bowl on an engine and flush)

but with the wonderful world of FI there is an o2 sensor and when you are crusing you are in closed loop and the car keeps runing at stoich aka 14.7 ideal for mpg. the car WILL componsate for simple flow mods. but when you get on it it goes into open loop where it runs off a set map here you will be sligtly leaner due to the mods. but since honda uses the same ECU for all same engine there is a HUGE saftey margin, my car ran at ~12:1 af which is a good AF for a turbo car.

in other words, no you arent SOL, you will get exactly what you are looking for!
if you keep you driving habits identical you will get better MPG but the thing is the car will sound MUCH betterand youll get on it much more

[endo]

Originally Posted by legacyo13

Just put on a CAI, intake, header, and exhaust. It'll give you the 2 - 3 more mpg and give you a bit more power, but not much. You could probably do better with a straight pipe, but then again, it's not legal in states with emissions (if you live in one of those states). Where I'm from, they dropped emissions altogether, and since I'm a resident here, I can straight pipe it wherever I want. But a straight pipe is the best way to go for power and better gas mileage.

I live in Maryland, so no straight pipe for me. I do a ton of driving, so reliability is important to me... so if there were a way to add the throttle body, intake manifold, intake, and exhaust and maintain the propper AFR, then I would.

[98civcEK]

Originally Posted by endo

I live in Maryland, so no straight pipe for me. I do a ton of driving, so reliability is important to me... so if there were a way to add the throttle body, intake manifold, intake, and exhaust and maintain the propper AFR, then I would.

what you just listed here will not change the AFR or make it nessecary to do so.

[soul 93]

Originally Posted by endo

I was thinking about stage 1 cams, cam gears, intake manifold, throttle body, valve springs, valves, and retainers all from Skunk2 (I figure that if I get it all from the same place at the same time that I could get a discount). A new clutch, light weight flywheel, and header back exhaust are also on the list. I understand that the cost of these parts outweighes the gas savings, but 127chp isn't enough for me... so the price is worth it.

he would certainly benefit from a tune......dunno how you think that these mods wouldnt affect his afr

and carbs compensate on there own....so it wouldnbt lean if it were carbed

[speedjunky01]

they will affect is AFs but at WOT ONLY! and at that they will be effected for the better since honda programed the ECUs super uber rich for a na engine.

anything below about 60% throtle the afs will all be set acording to the o2 sensor nothing else. I have these little mods and car never ping or detonates and I even advanced the timing 4 degrees. right now its about 85* and all is well.

no need for the skunk 2 im its a waist of money the stock y8 IM is awesome as is, unless you boost you will se minute gains.

as for the throttle body get one of a b series engine then with a drill portmatch the TB to the IM

[endo]

Now I'm confused... I have gotten different info from Soul 93, 98civicEK, kommon_sense, and speedjunky01. Everything was so much easier on my Impreza.