fuel consumption

[bnaellis]

I don't know where all these rumours come from that the cosmo gives terrible fuel consumption. I put £50 in the other day, the needle went up to 3/4 tank mark. I then did 112 miles and the needle was 1 notch under the 1/2 tank mark. Or was I not driving hard enough?

[kev-yorks]

Got to agree with you there Brian don't think there is that much diff in consumption between a fd or cosmo. Your motor will probably be like mine in that you can't run full boost all the time on a single so it improves the consumption figures. Certainly mine is better now than with the stock twins.
Kevin

[bnaellis]

Got to agree with you there Brian don't think there is that much diff in consumption between a fd or cosmo. Your motor will probably be like mine in that you can't run full boost all the time on a single so it improves the consumption figures. Certainly mine is better now than with the stock twins.
Kevin

What size turbo you running Kev?
Also my lcd display for the tv, sat nav, heater controls etc works but there is no display, is there a fuse for this do you know ?

[kev-yorks]

Hi Brian running a garret GT42 on mine. Gone the whole hog though 1600cc secondarys microtech ecu and manual box plus loads of bits and pieces.Bit of a stealth machine though unlike yours as it looks stock at first glance. For the display Dave Morris is the man to speak to. I've read there's issues with the power supply overheating for the display giving the effect you're getting, pretty sure Dave can get replacement units and the shippings pretty quick from Aus. If its not already been done Dave does a really good intercooler upgrade that bolts straight into the stock mounts about twice the cooling with really good flow.
Kevin

[antnicuk]

our cosmo was hurrendous and just got worse when we put it in the fd.put 70 quid in at geffs and ran out before we got home, its only 115 miles away! need another 15 quid to get home!

[DMRH]

I dont understand all this 18th century Miles & gallons.

However, my Cosmo will crack (just) 600km on a tank (85lt) if I cruise carefully along the highway. This drops to around 550km if I want to cruise over 120km/h

City cycle sees my Cosmo consumption around the 450km are per tank.

Thats thirsty in any language but you have to pay for the performance with petrol & lots of performance means lots of petrol........ :3gears-lh

[kev-yorks]

Dave's figures if i've done the conversion right are
120km/h(74.56mp/h) cruise 19.95mpg
+120km/h 18.23mpg
City 14.97mpg
All i can say is he shows a lot more restraint with his right foot than me. At the moment i'm probably looking at single figures when playing (95% of the time) and 14mpg when being sensible. These are only a guess though as i don't really check the mpg figures. I would also say though that i suspect my average speed is probably considerably more than Dave's as its very rare the clock(converted to mph) shows less than three figures.
But as Dave said at the bottom of his post You've got to put it in first before you can take it out and with a 20b you certainly get plenty of power out
Kevin

[normski]

Dave's figures if i've done the conversion right are
120km/h(74.56mp/h) cruise 19.95mpg
+120km/h 18.23mpg
City 14.97mpg
All i can say is he shows a lot more restraint with his right foot than me. At the moment i'm probably looking at single figures when playing (95% of the time) and 14mpg when being sensible. These are only a guess though as i don't really check the mpg figures. I would also say though that i suspect my average speed is probably considerably more than Dave's as its very rare the clock(converted to mph) shows less than three figures.
But as Dave said at the bottom of his post You've got to put it in first before you can take it out and with a 20b you certainly get plenty of power out
Kevin


So, Kev, what do you think my thing will do the gallon! 1 or 3 MPG :2Confused

[kev-yorks]

Recon you'll see high singles low doubles the same as me. The trouble is when its under your foot it takes too much restraint not to use it. Got a two stage water injection system just waiting to go on mine now so i think its time to stop playing with it and start turning up the boost once the weather turns for the better. i'm going to have a go at mapping myself this time as i've now got full datalogging and wideband a/f on her as well now. If it doesn't go to plan then i'll let one of the tuners do it for me but it'd be nice to get it done myself like the rest of the work. If i do get it mapped for me not sure if it will be Wgt or Reworx as the reworx crew seem to be doing quite a lot of mapping with water not sure how much Pip has done?
Kevin

[normski]

Ummm so not to sure myself. He's got to do my thing, although my system has the computer attached to monitor how much is stuffed into those chambers!

Don't foget to use the Methonal, although max it at 40% to distilled water. So the book says anyway!

[Ultraman_Cosmo]

any figures for a 13b cozzie?

[kev-yorks]

I would imagine its similar to the Auto FD as its the same engine slightly detuned. Nodoubt someone will post though.
Kevin

[ZillaKiller]

**** I could barely get 400km out of mine, running a bit rich though

[DMRH]

any figures for a 13b cozzie?

Best I ever did on a 13B-REW Cosmo was 550km highway cycle. Into a 72lt tank, that makes it better consumption than a 20B-REW version.

REgards

[Ultraman_Cosmo]

it would seem we're getting no more than around 320 kms (200 miles) to a tank.:( that's with my girlfriend commuting in the car, not driving particulary hard. would anyone have any suggestions for improving consumption?

[kev-yorks]

Might be worth getting the injectors cleaned, does seem low for a 13b as i'm getting similar or slightly better with mine i think. I never really check the consumption but it used a tank to get to the Thor dyno day and back which is about 280miles round trip and there was a reasonable amount of high speed on the way back.
Kevin

[DMRH]

it would seem we're getting no more than around 320 kms (200 miles) to a tank.:( that's with my girlfriend commuting in the car, not driving particulary hard. would anyone have any suggestions for improving consumption?

Yeah. 9 out of 10 times, its the Air Flow Meter

Get another AFM & try it. the spring tension goes in the AFM & allows the vane to be pushed in further for the same air. The ECU thinks its getting more air than it actually is so increases the fuel to suit. Your engine goes rich, your consumption goes up.

Compare spring tension with another one & use the one with the strongest spring.

Make sure it says "N390" on the part number as the (NF01) 20B version is calibrated differently.

REgards

[Ultraman_Cosmo]

thanks dave that does sound very much like a possibility! now, where can i find another air flow meter? :)

[DMRH]

thanks dave that does sound very much like a possibility! now, where can i find another air flow meter? :)

I have a few N390 AFM's but the issue here is whether they are any better than what you already have. I would hate you to waste your money & get one from me with even worse spring pressure thus giving even worse fuel consumption.

One way would be for you to send me yours & I compare all mine against yours in a test thus giving you the best one back. Another way is to purchase a new one from Mazda. Expectaround AU$500 for that.

Another way is to sourse a JC 13B-REW engine from a rotary wrecker/importer that has the AFM attached & do a deal.

REgards

[Tim_Burgess]

I did a run from Bristol up to see family in Woking recently and averaged 26 to the gallon from my 13b.

Mind you that was a steady Sunday morning motorway run at 75 - 80 mph. Dont really want to push my luck as I've got 6 points on the licence at the moment.