fuel consumption in my 260z

[DaveDimo]

hey guys i got a 74 260z 2+2 and its running an L26 with original flat tops in it. runs like a dream even with the flat tops.

 

i read in this book that the datsun has a 60L tank but that cant be right. can someone set me straight on talk size? im pressume it is a 40L tank

 

also if anyone has a similar car... what kind of kms are uz getting out of your cars. if i fill it up i think i will get about 300 maybe 320.

 

is that bad.?

[stevo_gj]

In my experience there is at least a 50L tank in a 75 260z.

 

I am getting 14.8L / 100km, but my carbys are running rich.

 

Best way to figure out your efficiency is write it down every time you fill it up.

[260Coupe]

A well tuned 260 should return 10 L/per 100 km on twin carbs hwy and around 13- 15 around town (depending on driving style and how you use the noise peddle)

 

My 260 runs 10 ltrs per 100 on the hwy cruising at 100-110 and around 15 ltrs around town.....that is on 240 carbs and a 4.11 diff

 

Zed fuel guages are notoriously inacurate (when mine is on empty there is 20 ltr left in the tank) so the only way to check fuel consumption is to record how much fuel your are putting as aposed to going by the fuel guage.

 

Zeds on triples should not be too far off on the same figures on hwy cruise but around town that could blow out to 20 l/100km  .

 

A little money spent on a decent dyno tune will same you plenty fuel consumption .

 

 

cheers

 

Alan

 

 

 

[DaveDimo]

allan teriffic reply!

[Scoota G]

Yea i mentioned fuel economy in a thread just recently. I'm getting 15 Litres per 100 klms on a city cycle with Triples Dellortos and an Auto  . Fuel tank capacity in the Haynes manual is listed as 60 litres.

[Scando]

Zed fuel guages are notoriously inacurate (when mine is on empty there is 20 ltr left in the tank)

 

That sounds familiar 

[DaveDimo]

geez 60L again haha. it seems to big it doesnt sound right to me and it doesnt feel right. next time my fuel gauge is on empty im gona drain the fuel into a bucket and see how much is left. then ill share my results i guess. but it was on empty last time and i only fit in 38L meaning there is another 22L in there. i gota get to the bottom of this.

 

i hate not knowing haha...

[oldmates260z]

Fuel tank from the manual is 60 litres

 

I get 9l/100klm on highway 12l/100klm round town for 100% stock 260z with roundtop SU's

[orange-Z]

I have been getting 15l/100km or worse in city driving with the round tops SU-HIF 06's.  Where do you get it tuned or do you do it yourself?

[DaveDimo]

well if its a 60l tank i should atleast get 500 km out of a tank. does this sound like something others have achived?

[stevo_gj]

City driving: if 12L /100km  -> 60L tank -> You'll get approx 500km.

 

Highway driving: if 9L/100km -> 60L tank -> You'll get 660 km.

 

 

For sake of comparison, my car in the city (75 260z l26 manual flat top carbs) -> 14.8L/100km -> 60L tank -> I'll get 405km

[260Coupe]

geez 60L again haha. it seems to big it doesnt sound right to me and it doesnt feel right. next time my fuel gauge is on empty im gona drain the fuel into a bucket and see how much is left. then ill share my results i guess. but it was on empty last time and i only fit in 38L meaning there is another 22L in there. i gota get to the bottom of this.

 

i hate not knowing haha...

No need to drain the tank.........the fuel tanks are definitely 60 ltr

I would suggest that you have the classic dodgy Z fuel guage.........all Zeds I have owned have had the same problem.......the guage will read empty and still have around 20 ltrs left in the tank.

Hey maybe it was a design feature ?............as ther is no low fuel light ........giving you 20 lts in reserve when on empty 

[zedevan]

does this sound like something others have achived?

 

i averaged around 400l per tank, ranging from around 450 to 350 depending on what i was doing (stock l26 with 240z carbs)

[Hunter]

Even when full my fuel gauge reads 3/4. Is there anyway I can remedy this?

[Scoota G]

I tried taking the fuel sender out and then bending it to resolve the issue but it had zero effect. I think that the best idea would require the donation of a fuel tank and then cut it in half to try to figure out once and for all this problem.

If you take the fuel sender out and move it by hand you can see that it is clearly capable of moving the gauge to a full tank but something prevents it. perhaps the length of the rod that holds the float could be shortened or maybe it hits on a baffle in the tank.

All suggestive but.

[RBZ 260]

definetly 60l tank in 2+2. 

 

error in readings

possible the float if it has a leak it will fill up with fuel and than show less fuel as it sinks more into the fuel.so bending it here or there wont improve things.

 

i didnt trust the 30yo plastic float inside the tank and replaced it with a float from a newer car with few easy mods. while i was at it also added the low fuel sensor.

 

im using a factory sender with r32 skyline gauge. and half tank means half tank and etc.... but i know you guys preffer the non mod way so i guess buy a new sender from nissan and verify that the gauge reads properly. this can easily be checked by looking at the service manual and fitting a pot (potentiometer or variable  resistor 0-100ohms, sendeer is approx 0-90) in the manual shows what ohms should each reading give. ie full , 3/4, 1/2 ,1/4 and empty. also shows how to do this.

 

most probably the gauge should be fine but the sender will cause most of your issues.

 

another thing someone may have fitted a sender from a differnt model. each sender is calibrated to the tank it has to go in. ie 2+2 tank has 2+2 sender and if 240z is differnet it will need 240 sender. even though they look same and can fit. the resistance curve is different.

 

i know my L28 240z with twin roundtops GUZZLES 15-20L if not more. as for 260z well thats got a different engine so figures are useless.

[Scoota G]

Just topped up the tank from near empty today 56.44 Litres and i could see the fuel in the filler neck.

[S30Mike]

My fuel consumption is shithouse to say the least, 90% city driving on Round top SUs running larger fuel jets, Ground cam and a few other upgrades $20 gets me about 80 - 100kms so about 400km a tank . Before i got it tuned it was even worse..

[dorifticon]

If I flog the living daylights out of my zed around town, I can get the fuel consumption as high as 10L per 100k's.  Highway consumption is in the 8's.

 

I am running the closed-combustion chamber, L24E head from an 83 skyline (including cams etc), and the factory ECU, on the 2.6 litre factory bottom end; and 95 octane fuel.

[Brabham]

Hey Mike,

            $20 gets you about 15L these days so I figure you are getting about 15L/100Km. Considering you are running the larger jets and cam that is pretty good in my book. BTW get about 10-12.5L/100KM in the Mk.1 so that makes your mileage look pretty good!  :D BTW do you run Valvemaster or equiv. and 98 Octane?

[S30Mike]

Yeah, it isnt too crazy at the moment, ive adapted into driving it pretty well now so its alot better.

 

Still occasionally does that retarded fuel pump click thing but nowhere near as often as it used to.

 

Btw whats valvemaster?

 

and i only normally run regular unleaded, is it a big difference to run 98 in the L series?

[260Coupe]

Mike

If you have a standard E88 head then this will have brass valve seats, unleaded fuul has no lead to lubricate valve seats and long term use will cause valve seat recession (compression of the valve seat into the head) and valve wear. "Valve Master" is a fuel additive which replaces the job of the lead (lubricates the valves) , it is not an octane boost as some my think .

 

I found my valve seats badly worn after a few years of not bothering with a lead replacement additive.........replaced them with stainless seats and problem solved . If you have the original period cylinder head (all manufactured pre 1986) then I would suggest you use a valve lubricant (unless you plan to do an engine refresh in the foreseeable future)

[S30Mike]

ahh so valvemaster is just a leaded additive.if thats the case i dont thnik i need it as the engine has been largely modified, and the guy i got it off said the additive wasent required as it was built for unleaded.

[HELLFIRE!]

I run a stock L26 with British SUs and get about 12L / 100Km.

[mrp69]

 

i think u didnt buy and old car for fuel consumption so just drive it cause you enjoy it

 

if you want fuel comsumption drive a charade lol

 

sell the zed and save the world we dont want more carbon emissions lol

 

my zeds got a v8 so i dont now comsumption all i know is when u put your foot down u watch the neddle go down lol

 

peter