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MR JONES
18-03-09, 01:26 AM
read in autotrader that driving at 56mph can get you 25% more mpg than driving at 75. hmm. tried it today in mondeo diesel and got 59 mpg at 56, and 43 mpg at 75 over 20 mile dual carriage way runs.
now. how would this relate to our economical v8s? if we ever felt the need to cruise economically
ian

mylesdw
18-03-09, 03:32 AM
In theory the difference would be even greater for a Cobra since the Mondeo is far more aerodynamic.

Edit: no that's rubbish, the difference should be much the same.

viperjim
18-03-09, 03:44 AM
why would you want to drive economically , im not condoning illegal driving , but if its economy you want buy a prius . Just my opinion but when my vipers on the road i intend to waste every gallon :-) :-)

Lloyd Barnes
18-03-09, 08:00 AM
read in autotrader that driving at 56mph can get you 25% more mpg than driving at 75. hmm. tried it today in mondeo diesel and got 59 mpg at 56, and 43 mpg at 75 over 20 mile dual carriage way runs.
now. how would this relate to our economical v8s? if we ever felt the need to cruise economically
ian


56mph is simply a number to be passed as rapidly as possible :mrgreen: My car seems to need refueling all the time and thats just running in the garage to get it tuned in :razz:

Martyn-ak427
18-03-09, 08:16 AM
Nothing wrong with the Prius, in fact my next project will be a Prius-based Cobra replica ;-)

wilf
18-03-09, 09:05 AM
Oh dear, can we recommend some treatment? You are obviously a very sick man. :mrgreen:

chr15w
18-03-09, 09:09 AM
Just my opinion but when my vipers on the road i intend to waste every gallon :-) :-)

When the Cobra is on the road NO gallon is wasted

But seriously, the drag created by all cars starts to increase dramatically over 55mph so the fuel consumption curve rises more steeply over that speed.

If going on a long run it would be economical (cheaper) to travel the boring bit at around 60mph then save the revs for the fun bit

dingocooke
18-03-09, 09:33 AM
If I want economy I take the daily driver, for me the cob is all about FUN (read my signature), and no consideration is given at all to fuel consumption; for the mileage we do, and the level of pampering these cars get, fuel cost is a tiny part of the overall cost per mile. One day youre going to be stone cold dead, you could be remembered as the guy who got 21mpg at 56mph in his cob, or the guy who just had fun !!! ;-)

Have fun whatever you choose and dont spare the horses!!

Sidecarbod
18-03-09, 09:42 AM
Nothing wrong with the Prius, in fact my next project will be a Prius-based Cobra replica ;-)


Nothing wrong with them as long as you don't buy one for "green" reasons. They might not puke out much in the way of emissions but don't forget the that the stuff used to make the batteries is dug out of massive landscape wrecking holes in the ground.

Anyway, I'll be buggered if I'm going to drive my cob at 56 MPH just to get it to go a few more miles. I work hard (sometimes) to earn the money to fuel my car, I'm darn well going to enjoy burning the stuff!

At the end of the day most cobs are only going to do around 3k miles a year so we are hardly going to make a difference to world pollution.

I really can not get 'my head round' this thread at all! :confused:

andicole0
18-03-09, 09:43 AM
56mph is simply a number to be passed as rapidly as possible :mrgreen: My car seems to need refueling all the time and thats just running in the garage to get it tuned in :razz:

Yes I think I'm about to finish my third tankful and only reading 230 on the odometer.

Just as a matter of interest if the national speed limit is lowered to 50 how will that affect cars such as my wifes S-Max that doesn't really go that slow in 6th gear? I always thought the most economy would be in the highest gear, but at that speed I think the engine would be doing under 1500 rpm, with practically no torque.

Andi.

Noel
18-03-09, 10:17 AM
Yes I think I'm about to finish my third tankful and only reading 230 on the odometer.

Just as a matter of interest if the national speed limit is lowered to 50 how will that affect cars such as my wifes S-Max that doesn't really go that slow in 6th gear? I always thought the most economy would be in the highest gear, but at that speed I think the engine would be doing under 1500 rpm, with practically no torque.

Andi.

Figures I'm fantasying about getting at the moment ;)

Got 55miles out of my first tank :(

Sidecarbod
18-03-09, 10:27 AM
Figures I'm fantasying about getting at the moment ;)

Got 55miles out of my first tank :(


Stop pratting about on the forum and sort your carb out then! :D

I've got a nice eddy 600 that you can have if you like!

Noel
18-03-09, 11:00 AM
Stop pratting about on the forum and sort your carb out then! :D

I've got a nice eddy 600 that you can have if you like!

Ho Ho :D

Sussed out the secondaries and have jets in kit to bring them down 8% 12% and 16%. Think I might grab the bull by the horns and go straight for 16% ;)

Dude
18-03-09, 11:10 AM
Figures I'm fantasying about getting at the moment ;)

Got 55miles out of my first tank :(

That sounds quite good! I bet they where 55 happy miles!! :D

Noel
18-03-09, 11:23 AM
That sounds quite good! I bet they where 55 happy miles!! :D

Unfortunately they weren't;) But now it is doing a lot more than that they are getting much happier :D

MR JONES
18-03-09, 11:31 AM
If going on a long run it would be economical (cheaper) to travel the boring bit at around 60mph then save the revs for the fun bit[/QUOTE]

taking it down to algarve for the summer, as i did last year, so i could cope with cruising at 60mph in the sunshine, then really enjoy it once i'm there

Neil O
18-03-09, 11:59 AM
But seriously, the drag created by all cars starts to increase dramatically over 55mph so the fuel consumption curve rises more steeply over that speed.


Why?
Does the air get thicker the faster you go?


I know, increased pressure is the cause right?

sumoboy
18-03-09, 12:03 PM
My wifes Jeep Cherokee is an Auto and won't drop into top gear until 62-63mph.

nikbj68
18-03-09, 12:20 PM
...taking it down to algarve for the summer, as i did last year, so i could cope with cruising at 60mph in the sunshine, then really enjoy it once i'm there
Jeezis, you`re a brave fella! The Portuguese drivers scare the crap out of me in a Rental, let alone my pride & Joy! On the plus side, nobody uses the big toll roads, so BLAST AWAY!!!!:cool:

Anyway, back on topic. I get 53+mpg from the Passat diesel @ 75-ish, and just over 60 @ 55, so not a vast difference.

My Dad reckoned on 3-5 mpg when racing the Cobra, but a gallon of petrol was 5 bob then, so filling his 40 gallon tank would have cost a tenner!!! :cool:


[aside] Why aren`t there V8 diesels? :rolleyes:

obsession
18-03-09, 12:30 PM
Jeezis, you`re a brave fella! The Portuguese drivers scare the crap out of me in a Rental, let alone my pride & Joy! On the plus side, nobody uses the big toll roads, so BLAST AWAY!!!!:cool:

Anyway, back on topic. I get 53+mpg from the Passat diesel @ 75-ish, and just over 60 @ 55, so not a vast difference.

My Dad reckoned on 3-5 mpg when racing the Cobra, but a gallon of petrol was 5 bob then, so filling his 40 gallon tank would have cost a tenner!!! :cool:


[aside] Why aren`t there V8 diesels? :rolleyes:

I'm going to build a cob with a V8 diesel from a range rover sport......oh, just woke up!!

Noel
18-03-09, 12:42 PM
Jeezis, you`re a brave fella! The Portuguese drivers scare the crap out of me in a Rental, let alone my pride & Joy! On the plus side, nobody uses the big toll roads, so BLAST AWAY!!!!:cool:

Anyway, back on topic. I get 53+mpg from the Passat diesel @ 75-ish, and just over 60 @ 55, so not a vast difference.

My Dad reckoned on 3-5 mpg when racing the Cobra, but a gallon of petrol was 5 bob then, so filling his 40 gallon tank would have cost a tenner!!! :cool:


[aside] Why aren`t there V8 diesels? :rolleyes:


I was getting that but was taking it easy :confused: :(

nikbj68
18-03-09, 12:48 PM
...My Dad reckoned on 3-5 mpg when racing the Cobra...
I was getting that but was taking it easy :confused: :(
That`s what you get for having a Chebby 427 rather than a Ford 289!

Noel
18-03-09, 12:54 PM
That`s what you get for having a Chebby 427 rather than a Ford 289!

Hopefully it is a LOT better after much dabbling with jets and rods ;) :D:D

Sidecarbod
18-03-09, 01:01 PM
Hopefully it is a LOT better after much dabbling with jets and rods ;) :D:D



"Dabbling" that's not what you were calling it yesterday, you sounded distinctly pi55ed off! ;)

Noel
18-03-09, 01:32 PM
"Dabbling" that's not what you were calling it yesterday, you sounded distinctly pi55ed off! ;)

I can see a light at the end of the tunnel, just hope it's not a train ;) :D

Richo427
18-03-09, 01:45 PM
Was'nt there a quote in a film once upon a time that went something like ' 55 miles per hour is dangerous '................:)

Ian 46
18-03-09, 02:27 PM
I have driven a Chevy powered Dax Tojeiro from Sheffield to Toulouse (approx 750 miles) cruising on the motorways between 80-90mph and returned an average of 22miles per gallon. I thought that was fantastic for a Repower RPM Performer stage of tune engine. It did have a Tremec box behind it with the tall 5th gear. Blatting round town etc., fuel fell to low teens however.

Ian

nikbj68
18-03-09, 03:49 PM
Was'nt there a quote in a film once upon a time that went something like ' 55 miles per hour is dangerous '................:)

Off the top of my head:

Graves:"Can you imagine doing this trip at 55?
Banner:"Driving at 55 miles per hour is unsafe!"
Graves:"It`s boring...that`s what makes it unsafe!!"
Banner:"You`re going slow enough to think you`re safe, but fast enough to kill ya!"

From the Gumball Rally. 8)

I really should get a life!

BrettG
18-03-09, 06:21 PM
Personally i cruise at 5mph so all the totty can see me. Works wonders till they see my ugly mug :)

realyweely
18-03-09, 06:25 PM
Personally i cruise at 5mph so all the totty can see me. Works wonders till they see my ugly mug :)

I thought Essex girls didnt care what blokes looked like?:):)

BrettG
18-03-09, 06:30 PM
Can sense a string of Essex Girl jokes coming my way.

dust
18-03-09, 06:57 PM
22 mpg this needs some thouht
would geting an injected engine give a much better mpg when driven "lively" over a carb engine
it may make a diference to my engine choice!

mind you 22 mpg if i go to the lakes thats mayby 200 miles at about 5 gallon that 50 its not soooo bad for a great time out

david

britbits
18-03-09, 07:31 PM
I will start the ball rolling. A blonde Essex girl was travelling to Melbourne. aboard a 747. After being in the air for a while she left her seat in economy and sat in a first class seat.The steward asked her politely to return to her seat to which she replied I am blonde and beautiful and I will sit where I like. The steward fetched the chief steward who politely asked her to return to her seat. Again she replied I am blonde and beautiful and I will sit where I like.The chief steward told the captain who said he would have a word with her as he was married to a blonde essex girl. After whispering something in the girls ear she got up and returned to her seat. The steward asked the captain what he had said. He replied, I told her that first class wasn't going to Melbourne.
Dave B

BrettG
18-03-09, 08:07 PM
I've always liked the one. An Essex girl playing hide and seek with a group of boys says "who ever finds me first can shag me, if no one can find me.......i'm in the shed"

mylesdw
18-03-09, 08:13 PM
I followed a van the other day on which was written:

"Women fake orgasms because they think men care!"

Amused me...

Clarkson
19-03-09, 12:53 AM
Hopefully it is a LOT better after much dabbling with jets and rods ;) :D:D


Bet you wished you got it dyno'd like I said to you last time!!:(

Your reply, Rolls royce don't dyno there engines!!:rolleyes:

You'll be needing a set of rings next due to excessive bore wash!

Noel
19-03-09, 01:05 PM
Bet you wished you got it dyno'd like I said to you last time!!:(

Your reply, Rolls royce don't dyno there engines!!:rolleyes:

You'll be needing a set of rings next due to excessive bore wash!

Ah you're full of mis-information again ;):p

The first thing I did when I got the engine was to book it into a dyno, 31 March was first available date.

I said Rolls Royce don't quote power figures and that mine was the same......"sufficient" ;)

It only had one run before the issue was identified and I immediately bought a calibration kit and stuck an Innovate LC-1 on it last Saturday with Pete and we got it running pretty good. We didn't go near the secondaries then but I have re-done those this week, although I shouldn't be using those for a while yet? :cool:

Are you going to the Grasshopper Sunday??

Sidecarbod
19-03-09, 02:25 PM
David,

I'm planning to go to that meet as long as the weather is good. I have a couple of spare threaded bosses and bungs for an LC1, you can have if one you like.

I actually bothered to read the instructions for my new LC1 on the train this morning. The back of the probe MUST be in fresh air all the time, it is used as a reference, therefore wacking the probe up the tail pipe ain't going to work! Apparently you can get some sort of adpator that will let you push the thing up the pipe whilst not subjecting the back of the probe to exhaust gases but it sounds like a right old bodge to me!

It would be nice to meet you, Noel talks about you all the time! ;)

Pete

chr15w
19-03-09, 02:28 PM
Why?
Does the air get thicker the faster you go?


I know, increased pressure is the cause right?

Yes & yes

If you go to a swimming pool and move your arm as fast as possible under the water you find that it gets harder the faster you go whereas moving your arm slowly isnt too hard at all. Wind resistance is the same and it starts to get harder around 60mph

Clarkson
19-03-09, 02:32 PM
Ah you're full of mis-information again ;):p

The first thing I did when I got the engine was to book it into a dyno, 31 March was first available date.

I said Rolls Royce don't quote power figures and that mine was the same......"sufficient" ;)

It only had one run before the issue was identified and I immediately bought a calibration kit and stuck an Innovate LC-1 on it last Saturday with Pete and we got it running pretty good. We didn't go near the secondaries then but I have re-done those this week, although I shouldn't be using those for a while yet? :cool:

Are you going to the Grasshopper Sunday??

Not full of misinfomation at all,just trying to help you make your life easier,but hey you know best,it's your car!;)

What Rolling road company you booking it in to? Should have got it dyno'd before fitting it.:rolleyes: As it will be difficult to load that engine in a lightweight car and also many places only go up to 250hp.:(

Not sure about Sunday yet, actually probaby not as it's mothers day! There again I could take the Mrs for lunch to the Grasshopper.
If I'm there I won't be in the Cob,as I have no brake discs on the front of my car!:(

Nobby
19-03-09, 02:33 PM
22 mpg this needs some thouht
would geting an injected engine give a much better mpg when driven "lively" over a carb engine
it may make a diference to my engine choice!

mind you 22 mpg if i go to the lakes thats mayby 200 miles at about 5 gallon that 50 its not soooo bad for a great time out

david

Yes in answer to your EFI question......

Better economy, better starting, no hesitation when accelerating, no messing about with jets and springs, no choke needed etc etc

The hairy chested macho carb fans out there will think you're gay of course..... but a small price to pay for all the other benefits EFI it gves you. :p

Clarkson
19-03-09, 02:35 PM
David,

I'm planning to go to that meet as long as the weather is good. I have a couple of spare threaded bosses and bungs for an LC1, you can have if one you like.

I actually bothered to read the instructions for my new LC1 on the train this morning. The back of the probe MUST be in fresh air all the time, it is used as a reference, therefore wacking the probe up the tail pipe ain't going to work! Apparently you can get some sort of adpator that will let you push the thing up the pipe whilst not subjecting the back of the probe to exhaust gases but it sounds like a right old bodge to me!

It would be nice to meet you, Noel talks about you all the time! ;)

Pete

Ok I will see you there!!

Noel talks too much full stop!!:p;)

dust
19-03-09, 09:45 PM
Yes in answer to your EFI question......

Better economy, better starting, no hesitation when accelerating, no messing about with jets and springs, no choke needed etc etc

The hairy chested macho carb fans out there will think you're gay of course..... but a small price to pay for all the other benefits EFI it gves you. :p
thanks nick
i thinkyour right efi is the way to go its got to be better in the long run(or on the long run)!
i need to look at some good efi engine suppliers any ideas?
"gay" if i have to paint my cob pink then so be it not

david

sumoboy
19-03-09, 09:57 PM
thanks nick
i thinkyour right efi is the way to go its got to be better in the long run(or on the long run)!
i need to look at some good efi engine suppliers any ideas?
"gay" if i have to paint my cob pink then so be it not

david


This looks ok to me:

http://cgi.ebay.com/ebaymotors/08-CORVETTE-Z06-LS7-7-0-Engine-505hp-2700miles-COMPLETE_W0QQcmdZViewItemQQ_trkparmsZ66Q3a2Q7c65Q3 a3Q7c39Q3a1Q7c240Q3a1318QQ_trksidZp3286Q2ec0Q2em14 QQhashZitem380110285660QQitemZ380110285660QQptZMot orsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Nobby
19-03-09, 10:15 PM
thanks nick
i thinkyour right efi is the way to go its got to be better in the long run(or on the long run)!
i need to look at some good efi engine suppliers any ideas?
"gay" if i have to paint my cob pink then so be it not

david


:p
Hi David,

British American Engines will build anything from mild to wild (I'm biased as they built mine) , Mike Huddart, Real Steel etc etc. Or you could import from the USA, although not really worth it as the exchange rate is rubbish at the moment.

Others will be along to recommend engine suppliers i'm sure. One thing I learned was too much power ain't enough, go for the best spec you can afford first time around rather that having to upgrade later on...

Good luck

dust
19-03-09, 10:25 PM
This looks ok to me:

http://cgi.ebay.com/ebaymotors/08-CORVETTE-Z06-LS7-7-0-Engine-505hp-2700miles-COMPLETE_W0QQcmdZViewItemQQ_trkparmsZ66Q3a2Q7c65Q3 a3Q7c39Q3a1Q7c240Q3a1318QQ_trksidZp3286Q2ec0Q2em14 QQhashZitem380110285660QQitemZ380110285660QQptZMot orsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
thanks
looks great to me to but i dont think it will fit in my hand luggage!
do you know if anybody ever put a merc engine in a cobra v12 from a 600 series !!!


david