Chuffer
CCCUK Member
No wonder fuel consumption is so low !!!
Fuel prices 🤑🤑🤑
- Thread starter Nassau65
- Start date
Roscobbc
Moderator
Fuel consumption on any 'tuned' engine doesn't have to be uneconomical. The basic changes need to improve performance are much the same as those required to make the engine more economical. Raised compression, improved inlet and exhaust flow and optimised timing will be much the same for both power and economy. Careful camshaft design can also improve power, efficiency and also economy.
teamzr1
Supporting vendor
My 1999 C5 outputs about 500 HP and 475 ft/lbs torque at flywheel, uses larger fuel injectors, custom CAM, 11.3:11 compression, etc with MN6 tranny,
transaxle has 3.73 gear, (stock was 3:42) bigger wheels/heavy tires and still can get over 30 MPG IF I am a wimp and cruise around 60 MPH (about 1,700 RPMs) on freeway
Back in the 1970s, my C3s (74,75 and 77) (maybe had 230 HP) were lucky to get 10 MPG
so thank all the electronics of today and doing custom tuning to dial performance in
while getting better fuel mileage then what stock was
transaxle has 3.73 gear, (stock was 3:42) bigger wheels/heavy tires and still can get over 30 MPG IF I am a wimp and cruise around 60 MPH (about 1,700 RPMs) on freeway
Back in the 1970s, my C3s (74,75 and 77) (maybe had 230 HP) were lucky to get 10 MPG
so thank all the electronics of today and doing custom tuning to dial performance in
while getting better fuel mileage then what stock was
Nassau65
CCCUK Member
454ci motors were know for their thirst, much like Chrysler’s 440ci. In the days when they were made, in the US it didn’t really matter much. The 454 only lasted a year after the first oil crisis in the corvette, and a couple of years in full size motors. Very sort after now stateside.
Roscobbc
Moderator
30 mpg in US gallons is about 33/34 mpg in 'English' (Imperial) gallons
With really stringent emission laws that came-in from '72 onwards manufacturers had already been forced to reduce compression ratio's from typically 10 or 10.5 to 1, down to 8.5 or 7.5 for most manufacturers for the 1971 model year. In 1972 ultra lean fuel mixtures and severely reduced ignition curves were required and engine running temperatures had to be significantly increased to some of the emission components to 'squeeze' through emissions controls. Ad-in accessories like A/C and car bodies with the 'new' heavyweight federal energy absorbing front and rear bumpers and it's surprising that they could pull their own weight. Then we had the scenario of mandated lead free gasoline and its amazing that cars like Pontiac's Transam continued for a few years. Our own Corvettes with sub 200 hp performance........don't need to say too much about that......
Big block Vettes after '72 can be improved in terms of MPG, making sure they run cooler and a modified ignition curve will help perhaps achieve 15/16 Imperial MPG - not brilliant - but also not a lot worse perhaps than one of the last higher output early 70's small blocks. Doesn't really matter really with the current cost of fuel as even a 30 mpg car is expensive to fuel-up.
Nassau65
CCCUK Member
Tell someone today you’ve got a car that does 30mpg they replay “ is that all it does?” People want 45-50 nowadays.
I remember once I went to the DVLA in Stanmore ( the old Army place) to register a car it was a 78 grand marquis brougham with a 460ci ( 7500cc) motor.
Anyway when I got to the counter the very young girl behind checked my form and queried the engine size. When I confirmed it she replied “ my god what is it? A space ship” and laughed. She said her cars a 1:2 litre and laughed.
I remember once I went to the DVLA in Stanmore ( the old Army place) to register a car it was a 78 grand marquis brougham with a 460ci ( 7500cc) motor.
Anyway when I got to the counter the very young girl behind checked my form and queried the engine size. When I confirmed it she replied “ my god what is it? A space ship” and laughed. She said her cars a 1:2 litre and laughed.
James Vette
CCCUK Member
Smiles per gallon.
Roscobbc
Moderator
I sometimes have non American car people asking the typicial question "what size is the engine", then perhaps trying to appear as though they have a little knowledge, repying to their own question "5 ltr, 5.7 litre"?. When I reply with " it was 7 litre, now its 8 litre, 8000 cc" I get a strange, quizzical disbelieving look, and and I know that some people will think that I'm lying!
Of course the next question is "what ever does it do to the gallon"?
richie500
CCCUK Member
Hi James, is a real speedster and not a
The guy who builds the engines tuned my vette
James Vette
CCCUK Member
@richie500 Yes it's a chesil. Exactly the same as the original but built like a kit car.
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Nassau65
CCCUK Member
Some of those kits are really cool. There’s always a silver one at the Enfield pageant, lovely build, looks the business
richie500
CCCUK Member
Dodged a bullet
I quit my last job 2 years ago due to stress. I was a Sales Manager for a very large company who decided it would be beneficial to the company to down grade my company car from BMW 3 series to a BMW 1 series 1.6D. (by the way the senior management kept their 5 & 7 series cars)
This is where it gets interesting, the government advisory fuel rates (which most large company's use) for a 1.6d is 11 pence per mile. My little car used to do 48mpg on average and i covered approx 20,000 business miles per year so that equates to 416 gallons of fuel at £8 a gallon = £3328 paid out. Company would then reimburse £2200 over a period of 12 months so i would have had to pay out approx £100 a month out of my own pocket just to do my job. I could only claim from my place of work so i still had to pay on top of that to cover the mileage to and from work and private like most people and the horrendous company car tax. So spare a thought for those driving company cars they are probably crying right now harder than you.
I quit my last job 2 years ago due to stress. I was a Sales Manager for a very large company who decided it would be beneficial to the company to down grade my company car from BMW 3 series to a BMW 1 series 1.6D. (by the way the senior management kept their 5 & 7 series cars)
This is where it gets interesting, the government advisory fuel rates (which most large company's use) for a 1.6d is 11 pence per mile. My little car used to do 48mpg on average and i covered approx 20,000 business miles per year so that equates to 416 gallons of fuel at £8 a gallon = £3328 paid out. Company would then reimburse £2200 over a period of 12 months so i would have had to pay out approx £100 a month out of my own pocket just to do my job. I could only claim from my place of work so i still had to pay on top of that to cover the mileage to and from work and private like most people and the horrendous company car tax. So spare a thought for those driving company cars they are probably crying right now harder than you.
Roscobbc
Moderator
I had 40 years of some really crappy company cars. Its often far worse than you have described with a company car. Firstly you can possibly be forced to drive a car that you don't like. There was a big push from a lot of employers to have diesel cars - (we know where that all went). Very often the car they'll provide you with could be extremely 'tax inefficient'. The employer will have done a deal with a car dealer or manufacturer for a certain type of car - that very often would be a tax inefficent vehicle.
People may think you are lucky having a company car but you'll pay in the form of Benefit In Kind taxation. You'll pay even more if they provide free fuel. Get the wrong car - perhaps a larger engined petrol Ford, Vauxhall or similar and possibly pay thousands of pounds extra tax per year.
So you decide to provide your own car and claim the megre milage allowance that HMG allow, thinking to yourself that you'll get an old banger for perhaps 6 or 7 hundred quid and if it goes badly wrong, simply scrap it and get something else.......no, you can't do that - under HMG rules and regs the car has to be three years old or less.
The real trick perhaps is to contract hire a vehicle, plug-in hybrids are 'kind' of taxation - as are electric vehicles.......but can you justify the 4 or 5 hundred quid a month?
Roscobbc
Moderator
100% John - as a 'user' you need to be 'ahead of the curve' so to speak re. selection of company cars......and yes choose self charging hybrid and you'll save a gradually diminishing amount of BIK - you'll do better with a 'plug-in' hybrid (and you don't even need to use the 'plug-in' facility to get the benefit) - choose a full electric vehicle and you will currently get far more BIL benefit - you company also pro-rata financially benefits.......currently. I emphasise the word 'Currently' as HMG are continually 'moving the goalposts', encouraging use of supposedly 'green' vehicles and then later 'pulling' the benefits in successive years of use.
Chuffer
CCCUK Member
Blimey ! That is steep ! I have just filled up the C3 today just off the A5 in Milton Keynes with the full fat V Power petrol at £1.789 / litre and that was bad enough .
Nassau65
CCCUK Member
That £2 a litre diesel is getting closer
