Author Topic: Fuel economy Triples  (Read 4507 times)

Offline Scoota G

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Fuel economy Triples
« on: October 01, 2008, 04:28:42 PM »
Running L26 with an Auto with N42 head,Triple Dellortos, Genie Headers through a 2 1/4 system electronic ignition and a thermo fan i'm getting 85 Klms for 13 litres City Cycle
Just wondering what figures other people are getting triples or not!
Technology costs a money and a money we don't got.

Offline stevo_gj

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Re: Fuel economy Triples
« Reply #1 on: October 01, 2008, 04:53:19 PM »
I keep accurate records of fuel usage and the odo readings. I'll do a quick calc and give you my average fuel efficiency.

Edit: Well your 13/85 is the same as 15.29L/100km

I am currently running the stock twin hitachi carbs on my L26. I am using data from July to present.

Since I bought the car I have had a fuel efficiency of 13.05 L/100km.

I did get a manual conversion though,

While I had an Auto my efficiency was: 12.8L/100km

Since the Manual conversion my fuel efficiency is: 14.6L/100km

Wow, that's absolutely shiver. I know V8s who use less...
« Last Edit: October 01, 2008, 05:09:16 PM by stevo_gj »

Offline Zeddophile

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Re: Fuel economy Triples
« Reply #2 on: October 01, 2008, 05:03:35 PM »
Quote
Running L26 with an Auto with N42 head,Triple Dellortos, Genie Headers through a 2 1/4 system electronic ignition and a thermo fan i'm getting 85 Klms for 13 litres City Cycle

Sounds pretty reasonable to me - my 2 litre Alfa with twin dellortos used to do the same figures, so you're going well I figure.

Anyway, not many people are going to do worse than my 4.6v8 rangey - 22l/100km in the city  :o
Current:
'84 Range Rover, 4 inch lift, 4.6l V8, Megasquirt, Rear diff lock, 34' tyres.
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'80 Alfetta GTV - Group S build in slow progress

RIP:
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Offline Scoota G

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Re: Fuel economy Triples
« Reply #3 on: October 01, 2008, 05:15:06 PM »
I forgot to mention that the 13 Litres was $20 worth and i'm not exactly light on the throttle as i "Juz Luv the sound of triples in the mornin".
Technology costs a money and a money we don't got.

Offline Mr240z

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Re: Fuel economy Triples
« Reply #4 on: February 12, 2009, 04:10:07 PM »
After 15 years of Zed ownership, I have done the fuel test.

L24 with E88 head ported and polished, large valves inl & exh

Mild cam for use in stock or near. stock engines. 58721 IN. 39/73. EX.75/37. 292. 292. 225. 225. 108 .495" .495". 3000. 6500. Medium street performance cam

Triple 45 Weber's, 2 1/2 inch exhaust, 280zx dissy, MSD Ing, 5 speed 260z box
And a heavy right foot.

Got new speedo cable so i started the trip meter, added 30L fuel from empty
Fuel level is just a tad above empty today and I,ve done 54.8 miles.
Is this bad and what am I doing wrong.

Good point = Its going pretty hard at the moment.

Any comments would be welcome
                                                                       Pauly ;D
30L fuel = 54.8 miles
« Last Edit: February 12, 2009, 04:11:54 PM by Mr240z »
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Offline XRQTR

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Re: Fuel economy Triples
« Reply #5 on: February 12, 2009, 04:33:26 PM »
Nah that's not bad






That's absolutely shyyyyyte..... that's around 35 litres per 100km of travel, or alternatively around 3 litres of fuel per km of travel, most trucks get better efficiency thatn that, get it sorted

I boot it around most of the time and I still get around 15l/100km, L28, ported n42 head, triple Mikuni 45's, actually i got 14l/100 using Caltex 98, I usually use BP or Mobil 98, I'll see how this tank of BP goes and I may change to Caltex if it's back up again.

Offline Scoota G

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Re: Fuel economy Triples
« Reply #6 on: February 12, 2009, 05:12:49 PM »
We need the data from your Carbies ie: Emulsion tubes, Main Jets, Idle jets ...Blah blah blah and then go from there.

Oh and does the Exhaust pop, do you get backfiring through the carbs and the colour of the Tailpipe and plugs.
Technology costs a money and a money we don't got.

Offline Mr240z

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Re: Fuel economy Triples
« Reply #7 on: February 12, 2009, 05:25:31 PM »
Get it sorted, Where do I start

When i put my foot down i can see a cloud of unburnt fuel out the back (grey to black smoke)
I take it to a weber specialist (so he says) what would you say is the problem.

Just read your post scootag and yes i do get alot for backfire and the plugs do fouled up alot
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Offline Scoota G

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Re: Fuel economy Triples
« Reply #8 on: February 12, 2009, 05:47:25 PM »
Without a doubt it the jets , emulsion tubes but probably not the idles. Do you have the Des Hamill "How to tune" book?

Maybe we also need a guide/ spreadsheet for webers.

If any other members are running webers and have their stats could you please post.


Pauly could you please post all your other equipment you run ... From spark plug type and anything else you run :)
« Last Edit: February 12, 2009, 05:57:04 PM by scootag »
Technology costs a money and a money we don't got.

Offline Mr240z

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Re: Fuel economy Triples
« Reply #9 on: February 12, 2009, 07:00:17 PM »
Can i pull the main jets, emulsion tubes out without detuning the weber not that its tuned to start with.

Mark i,ll try to check out the internals tomorrow if i can work it out.
When i brought these Weber's about 10 years ago, I went though about 3 sets of everything
jets, tubes etc and a shiver load of johnny cash. And the fuel economy has allways been the same
(shiver house) If I sit on the motorway and plant my foot I can see the fuel gauge needle moving downwards. Does this mean I,m not getting the best performance out of my motor.
And when i sort this out can i fit these to my L28 motor that i,m building from a L24 without going though this again.

p.s I,m running BP6E  NGK V-grove plugs with 10mm top gun leads
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Offline 68GTCS

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Re: Fuel economy Triples
« Reply #10 on: February 12, 2009, 08:03:36 PM »
I'm amazed at the high fuel consumption - what sort of performance are your engines giving?

I've just got a bog standard 240 and thought there was something wrong when it was using the same 13L/100ks as my '68 289 HiPo V8 does in the 200kg heavier mustang.  Add to that the performance is pedestrian at 9sec to 60 in the datsun while the mustang will do it in 6 seconds for little more than those 13L.

These results make me wonder if the things I had in mind to fix the problem (head port/polish, exhaust, electronic distributer, tune-up) won't make it worse?

Still, petrol is very cheap and such great fun to burn!

Offline Mr240z

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Re: Fuel economy Triples
« Reply #11 on: February 14, 2009, 10:45:37 AM »
Hey Mark i pulled the emulsion tubes out and cant find any markings on them and same with the jets on the ens of them.
The main jets on the bottom of the tubes, Looks to have pretty big holes in them.
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Offline Mick280zx

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Re: Fuel economy Triples
« Reply #12 on: February 18, 2009, 02:34:17 PM »
I'm amazed at the high fuel consumption - what sort of performance are your engines giving?

I've just got a bog standard 240 and thought there was something wrong when it was using the same 13L/100ks as my '68 289 HiPo V8 does in the 200kg heavier mustang.  Add to that the performance is pedestrian at 9sec to 60 in the datsun while the mustang will do it in 6 seconds for little more than those 13L.

These results make me wonder if the things I had in mind to fix the problem (head port/polish, exhaust, electronic distributer, tune-up) won't make it worse?

Still, petrol is very cheap and such great fun to burn!

Well they say that headwork, bigger cams etc doesn't always make for a positive result.

Some of the pom magazines I read publish the results of dyno days where regular joes bring in their cars and have them dyno'd- the results are mind boggling and rarely correspond positively with the specs of the engine given by the owner. Bog stock cars smash the HP results given by cars that have had thousands spent on them.

I guess the dyno tune is the only way.

Offline warrenz

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Re: Fuel economy Triples
« Reply #13 on: March 02, 2009, 07:22:01 PM »
I finally have some fuel consumption figures after the weekend run to Apollo Bay.

The around town consumption was 12.5 l/100Km (over 297km's) which includes hard accelaration

I filled up before and after the Apollo Bay run which included a hammering through the Ottway's on the way back and the consumption was 10.8 l/100Km. (over 284km's)

The plugs are  a nice brown colour and the exhaust pipe is black.

I am pretty happy with that.

Warren
« Last Edit: March 04, 2009, 06:44:41 PM by warrenz »
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Offline ol_skl_jp

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Re: Fuel economy Triples
« Reply #14 on: March 02, 2009, 08:41:04 PM »
I got just over 400k's to the tank on the way to lakes entrance, thats highway driving. Plugs are a good color and exhaust is also black. This is all after Mark tinkered with my carbs. I'm happy with them but it runs a bit hot on the highway. Thanks again Mark (scootag)

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Re: Fuel economy Triples
« Reply #14 on: March 02, 2009, 08:41:04 PM »