I guess I never posted this as a thread, I've said it multiple times before in other threads but now I have a direct link to point to cause I'm tired of explaining it....



Current figures are at

30 MPG city/34 MPG Highway

Current Setup:
6spd Manual w/ HLSD RS6F51H out of a '03 Sentra Spec V w/ 107k miles.
Lightweight (For a 6spd but not overall) FW from Fidanza
Unorthodox UDP
Bomz SRI
OBX 3.5 Headers for the 02-03
Magnaflow High Flow Cat
Cattman 3" Catback
17" G35C Rims 225/50f 235/45r
Full interior (Sortof )
No O2 Sensors
P/N Sensor Disconected
Gear Sensor thingy (forgot the name) disconnected

I've achieved up to 36 with this setup, but not consistent enough for me to say I get 36 highway (matter in fact it was before my O2 sensor wiring ate it I got 36, maybe I'll re-do it? Nahhhh, car runs more consistently w/o them).

I've been getting 35esque lately and higher city mpg, this may be due to the JWT pop charger, I need to take another mini road trip to confirm this.

I still have the record of 38mpg which has never been repeated, I drove 6hrs on less than a half of tank on gas (From OKC->Manhattan, KS), on a previous setup (25/27 one)

Previous Setups and their MPG

25/27mpg
Stock 5mt RS5F50A
Warpspeed Y-pipe+Exhaust leak mod
Magnaflow High Flow Cat
Bomz SRI
Unorthodox Racing UDP
Same Wheels.

27/29mpg
(Note: I was on this setup for an extremely short amount of time, these figures are guesses based on a few full tanks of gas)
RS5F50A
OBX 3.5 Headers
High Flow Cat
3" Catback
Bomz SRI
UDP
same wheels

So, you should go 6spd w/ your 4th gen and get that MPG yo

 

not bad numbers bro, thats really hard to achieve with a 12 year old ride very impressive my best numbers were 28/30

 

Awesome w/ the city mileage for an auto!!! That SC helpin out quite a bit I see!

 

oh yes sir and no complaints at all until I floor it then it drops dramatically but overall my milage is tons better with this setup

 

What rpms do you typically cruise at for both city and highway?

 

Highway 2.7-2.9k (77-83mph)

City I keep it around 2k, rarely go over 2.5, I do 2-4-6th (40mph+) or 2-4-5th(below 40mph) pending on the speed I plan on holding.

 

Biggest difference maker is that 6th gear!!

 

Did you factor in a correction for different diameter tires between stock and your current setup?

 

 

i've gotten 34ish freewaywith only a y-pipe when i was still auto

 

meh. we have the short geared 6mt; 4.144, not 3.817. so the cruising benefits of gear 6 is minimal. what's helping out the most is the efficiency of a well built 6mt vs a 4auto.

 

I don't think so, see below.

What'chu talkin about willis?

I've gotten 38 w/ only a y-pipe while I was 5mt

Now this is where I think the effieciency comes out, because of the short geared 6mt I have a lot of room to play with rpms keeping them at 2k while in the city.

Just think of it like this, while cruising around in your 5mt, remember I'm ALWAYS 500rpm lower, yet the gears are still shorter, so I'm not bogging the car.

 

I need more revs to keep 70 on the freeway than you. 2.8 or so while 2.8 gets you to near 80.

 

I envy your mileage

 

Only if u promise to help me install .

But with the different gear ratios for the 6spd...i believe those numbers. THats pretty sweet Aack

 

I wants that mpg too. This may make me wanna do a 6mt swap when I 35 swap

 

Nice milage man. Jealous. You have sims for all of your o2s?

 

I think 2.8 is pretty much 80 lol. 3k is 85, I know that.

I mean well we have this 6spd from a sentra here... It has something written in arabic, I think in english its VICIOUS MO'S TRANNY.

Sure, if you'll house me up if I get lucky enough to buy that SE-L for sale in your area.

DO EEET

No, I have CEL's for all of them though (Heater fuse is blown because of the fried wiring thanks to my headers)

 

Haha and you still have great mileage, im about to burn mine too lol.

 

What he's saying is...

When we change our wheel/tire combo, we should try to match the same overall diameter as the stock setup. Otherwise, they'll be a marginal error in the speedometer reading.

 

^^ there is a tire size calculator online that will tell u how muich differenece in speed vs speedometer when u change tire size.

I forget what the website name is

 

And did either of you guys check my tire setup with the current rims? Or just post that to be saying that

 

What'chu talkin about willis?




You asked Willis what he's was talking about, so I figured I'd to clear it up for him..lol..No I havent checked into your setup. However, it is one of many factors in reading mileage accurately. And this is what we're all are doing here, looking at every possible factor that could be affecting your mileage.

Correct me if I'm wrong but our cars are programmed to read miles based on the revolutions of our stock wheel diameter. And if it is altered by either bigger or smaller wheel diameter, the reading will not be accurate. That being said, your numbers could be even higher if your wheel diameter size is larger than stock because the odometer will read lower. Theres a mathematical formula out there that gives you the multiplication factor to get a mileage reading based off the diameter difference from stock to lets call it aftermarket wheels...

 

I'm kind of messing with you guys, I know what you guys all meant, just shocking that neither of you actually checked the tire sizes before even posting it.... 225/50/17 is slightly taller than stock, making my speedo read slower than it is, so in reality I'm getting better MPG than I state, but it's only off by so very little that I negate it.

 

you suck... nuff said...

 

yo that 6th gear should have been granted with the introduction of DEK, nissan really slacked off in that department. everytime i hit 90mph it clearly feels like the powerband calls for another gear. sadly there is none to slam into @ 100mph like a true bad **** street racer LOL........... this is all stock too !

epic numbers. i know my stock 5th gen is easily capeable of 30mpg highway but to get that in the city is crazy.

 

Bring it bish, July 29th, or Early august, pick your poison....

Maybe with the 5.5's gearing, my gearing will not benefit the DE-K's lack of tq @ redline.

 

thought the spec v 6spd was same as 5.5?

 

No, same as the 6th gen.

5.5s 6mt gearing is pretty much a 5MT w/ a 6th gear (cept 3rd is short and 4th is long)

6th gen/spec v gearing is close to your typical Honda with a taller 6th.

 

no experience with any of them. STI 6spd is where its at for me. shortttttttttt

 

Just looked it up, I'm a tad bit longer than STI's but only a few mph per gear.

 

The most accurate mpg data is based on using up a full tank of gas. When the needle is on 1/2 tank quite a bit more than 1/2 tank has been consumed.

Op, do you have data based on several tankfuls of gas where the tank has been almost emptied. There is too much error involved in partial tank estimates given the variability on how full the tank is.

When I go on road trips I fill up to the point that the tank is right full, just not the 1st click and then I run it very low if I can. I have achieved more than 550 miles to a tank, ie. 31 mpg, several times.

My car is a Canadian model, a 95SE, 5-speed, with 87,333 mostly highway miles. It runs on the stock sawblades and the performance mods are a Budget stainless steel y-pipe and K&N panel filter. I used 0w30 synthetic oil and synthetic gear oil and over inflate my tires by 2 or 3 psi.

 

After driving to Manhattan, KS from Houston, TX over 15 times I've ascertained the accuracy of my needle and I know what MPG I'm getting based on my location and how much gas I've filled up with.

I knew there were going to be doubters, this is why i did not ask a question in my original post, it was a mere statement.

You can argue the numbers but you can not argue the facts, I can drive over 8hrs on one tank of gas (Houston, TX-> Wichita, KS used a smidge over 16 gallons and on my way back didn't get so good mpg Manhattan, KS to Ferris, TX used nearly 17.5 gallons), this was not possible when I had a 5mt (except that one fluke incident of nearly 38mpg, drove about 8hrs on that tank), I could only go from Houston->OKC and be on fumes (or Manhattan to Norman, OK)

 

I need that MPG. I do alot of driving and right now my MPG suck a$$ compared to the numbers you guys are posting. Right now I'm gettin about 23 MPG on the highway. And the most I've ever gotten is 26 on the highway. The most I'll manage is around 360 on a tank of gas and it annoys me because when I had my 99 se-l auto I could get 450-500 depending on how much I put my right foot down.

I have warpspeed y, fidanza flywheel, stock exhaust, SRI, and right now I'm running my stock se 5 spokes.. I don't get it

 

I need to figure out y im not gettin that

 

So what distances are you quoting on those drives and gallons? What is the farthest you have driven on a tankful of gas? How many miles was the smidge over 16 gallons and the nearly 17.5 gallons? What is the terrain like?

My 550+ miles involves going from sea level to 6,000 feet in elevation, back down to 1,200 feet and the reverse coming home.

QUOTE=aackshun;8122584]After driving to Manhattan, KS from Houston, TX over 15 times I've ascertained the accuracy of my needle and I know what MPG I'm getting based on my location and how much gas I've filled up with.

I knew there were going to be doubters, this is why i did not ask a question in my original post, it was a mere statement.

You can argue the numbers but you can not argue the facts, I can drive over 8hrs on one tank of gas (Houston, TX-> Wichita, KS used a smidge over 16 gallons and on my way back didn't get so good mpg Manhattan, KS to Ferris, TX used nearly 17.5 gallons), this was not possible when I had a 5mt (except that one fluke incident of nearly 38mpg, drove about 8hrs on that tank), I could only go from Houston->OKC and be on fumes (or Manhattan to Norman, OK)[/QUOTE]

 

i get about 20 mpg in mixed city/highway driving. the farthest i went on a tank was 320 miles, and that was all highway.

 

you got some problems 4th Gens and 00-01 usually get 450-500+/tank....My modded 5.5th Gen can get 375-450 on the freeway depending on traffic, accidents, or cruisining speed usually 75-85 mph....

 

Something else a lot of people need to consider when talking about gas mileage is the size of their rims. Lot's of people are not factoring in basic physics when it comes to rim sizes and tire sizes. The larger you go and the more physical tread that has to be pushed, the lower your mpg's are gonna be. Simply saying cause I know we got many people on these forums throwing 18's and up on cars that were designed to operate on 16's.

(of course I am aware that other set-ups, i.e. headers and exhaust, may negate this a bit, but it's something to consider)

 

it was like 580 miles, again these are rough guesses based on google maps because I did not write down the exact mileage and I do not remember where I got gas in Wichita.

On the way back down it was 540ish, again didn't write it down, I only kept track of it at the time.

The elevation in Manhattan, KS is 1,020 feet.

Houston is pretty much sea level.

I always get better MPG going up than going back (damn 91 octane? It's the only thing I can think of is the problem).

As for the rim thing....

I didn't drive on my mustang 16s that much but I did not notice an increase in MPG, maybe it was 1mpg at the MOST, I wish I coudl take a road trip on my other set of rims but I'm sure my drag radials won't like it too much....