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Noel
07-04-08, 05:39 PM
Just been down to Devon for the SW Meet and thought it was about time I bit the bullet and verified what fuel consumption I could get. I have always advocated that it should not make any difference what it was, if you are worried about fuel consumption..... get a hybrid. But anyway, I was shocked.......

Just over 200 miles each way, M25, M4 and M5 with some "A" roads at each end and a couple of water/fuel stops in each direction. Kept to 70ish the majority of the time, stretching the right foot occasionally ;), with the engine running at approx 2400rpm when on the motorways.

journey down.......19.7 mpg
journey back........20.1 mpg

that's on a SBC 383cu in with an Edelbrock 600cfm carb :shock:

I bet an LS would have trouble matching that :p and I think says a lot for Jez and Ian at British American Engines :cool:


I could nearly use it as a daily run-around :D, but don't get me wrong, I can still make that fuel gauge move like a tacho when I'm having fun :rolleyes:

CycleSi
07-04-08, 05:50 PM
Noel,

You're letting the V8 side down with that 'modern fuel efficiency' - a maximum of 8 mpg is acceptable.

You clearly need to have another 'roadtrip' with me.

Off now to increase my carbon footprint courtesy of some high octane petrol and nitrous !

CycleSi

Noel
07-04-08, 06:05 PM
Noel,

You're letting the V8 side down with that 'modern fuel efficiency' - a maximum of 8 mpg is acceptable.

You clearly need to have another 'roadtrip' with me.

Off now to increase my carbon footprint courtesy of some high octane petrol and nitrous !

CycleSi


LOL.....you're right, I would never see double figures when I'm out with you :p

chedz
07-04-08, 06:14 PM
Noel, that's impressive, about the same as my 3.5 around town/lanes.

Do you know how/what the guys at BAE did to tune up the carb? Did they use lambda probes on the rolling road when they built it or do they just "know" what setup for the carb for an engine of that spec?

Pete and I are about to do some work on fine tuning carbs and are "investing" in some kit, just wondered what the pros use?

cheers

Graham

Noel
07-04-08, 06:19 PM
Don't laugh, but Jez use's his eyes ;) To quote "if your eyes don't water when you start her up......it's too lean"??????

Obviously he has years and years of experience and just "knows" when it sounds right. He sets the timing with a strobe and then the mixture by experience.........sickening :mrgreen:

I have a gas analyser if it's of any use?

Purple AK
07-04-08, 06:26 PM
Must be the SW air Noel ;) Seriously though, I always get 20+mpg on the long runs. 29mpg was my best effort :-D

KevinW
07-04-08, 06:32 PM
I talked to Mike Huddard about mpg and big blocks sometime ago.
He told me that a 390FE properly set up should see in excess of 20mpg on a long trip.
Hopefully he'll be along to confirm that.

Kevin

legend
07-04-08, 06:55 PM
Kevin, I hope Mike does confirm that but I doubt it with Tony 'LEADFOOT' driving it.

runt
07-04-08, 06:59 PM
So.. my favourite engines from the Golden Age of Motoring are..efficient, too.. I take it Mike wasn't referring to a 390FE pulling a T-Bird along..?
My Ford Windsor probably wouldn't be so bad either.. if I didn't keep using all the go-juice flooding it on cold starts!

Paul.;)

Noel
07-04-08, 07:17 PM
Must be the SW air Noel ;) Seriously though, I always get 20+mpg on the long runs. 29mpg was my best effort :-D

That is SERIOUSLY impressive Chris :mrgreen: :mrgreen:

wilf
07-04-08, 07:37 PM
Not too difficult really if you have a disciplined right foot. :mrgreen:

Thing is, you can go REALLY lean in the cruise at light throttle openings. If you set the carb up to run at 14:1 or somesuch at light throttle openings, you are wasting fuel. You can go far far leaner than that. Can't give you a figure, depends on your particular engine. Basically you can lean it out until it starts to misfire, then richen a touch.

NB - ONLY for "cruise" conditions - any lean-ness at WOT is a problem. The above is for primary barrels only at light throttle openings. Secondaries should always be tuned for correct mxture.

dingocooke
07-04-08, 07:40 PM
as many a lotus elan owner can testify, you can be too lean even at part throttle and do damage; not usually a problem with a Holley though; as rich as Bill gates usually....

KevinW
07-04-08, 07:45 PM
So.. my favourite engines from the Golden Age of Motoring are..efficient, too.. I take it Mike wasn't referring to a 390FE pulling a T-Bird along..?

Paul.;)

.. er yes I think he was, but I'll pm him to check

snakebite
08-04-08, 12:06 PM
journey down.......19.7 mpg
journey back........20.1 mpg

that's on a SBC 383cu in with an Edelbrock 600cfm carb :shock:

I bet an LS would have trouble matching that :p and I think says a lot for Jez and Ian at British American Engines :cool:




Hi Noel

Nice to meet you on Sunday:) As for " I bet an LS would have trouble matching that" ..........no problem at all, must average 25mpg+ cruisin' :mrgreen:

Clarkson
08-04-08, 12:24 PM
Best I got 20mpg last year to the Ring,but the worst I have seen mine is a tank of fuel (50 worth) to 3 laps of the ring,infact I never got the full 3 laps as I ran out and had to add a gallon on the track then limped it back to the pits!!:mad::mad:

I also done over half a tank of fuel in 15mins driving flat out 145mph in 4th gear coming back home.:-D:-D

Georgio
08-04-08, 12:51 PM
Creditable figures - I barely break 21mpg with a Piper-cammed Rover 3.5 on rejetted SUs (set up by Southern Carbs), but then I do like to hear it rev!
Incidentally, I called at Sainsbury's in Epsom last week on my first run out this year to see the LRP Four-Star pumps have all gone. They said it was officially withdrawn at the end of March but they haven't had any for weeks. They were the last garages to stock it, unless any of you know differently?
So if you don't have a converted engine, be sure to carry plenty of whatever additive you've chosen.
Originally LRP was due to be phased out by 2006-7 I believe, so we've had some sort of stay of execution. Reigate Heath Garage sells the real 98 octane leaded McCoy I believe. Georgio

Noel
08-04-08, 12:57 PM
Hi Noel

Nice to meet you on Sunday:) As for " I bet an LS would have trouble matching that" ..........no problem at all, must average 25mpg+ cruisin' :mrgreen:

Thought it might Steve.....sounded nice when you left the car park 8)

Noel
08-04-08, 12:59 PM
Best I got 20mpg last year to the Ring,but the worst I have seen mine is a tank of fuel (50 worth) to 3 laps of the ring,infact I never got the full 3 laps as I ran out and had to add a gallon on the track then limped it back to the pits!!:mad::mad:

I also done over half a tank of fuel in 15mins driving flat out 145mph in 4th gear coming back home.:-D:-D


Now if you and CycleSi ever went out together for a cruise you would never make it to the next garage?? :-D :cool:

Clarkson
08-04-08, 01:16 PM
Now if you and CycleSi ever went out together for a cruise you would never make it to the next garage?? :-D :cool:

No thanks, it's bad enough going out for a drive with V8 BJC!:-D:-D

nuf_said
08-04-08, 02:05 PM
I must have 'sumfink' wrong - only getting about 9 or 10 mpg, and that's out of a little chevrolet 305 (5 litres) and not too heavy a right foot. Very fumy exhaust - you see cyclists in the rear view mirror fall off clutching their chests!

I reckon I pay for a full tank of petrol and push half of it unused back to mother nature through the sidepipes.

Ken Coleman at EDA sugests a different cam - "but while you're at it swap the engine as well, and get a 383".

Nuf Said

CycleSi
08-04-08, 02:08 PM
Now if you and CycleSi ever went out together for a cruise you would never make it to the next garage?? :-D :cool:

Maybe so, but we would get there damn quick !!!

Miket
08-04-08, 02:33 PM
Thought it might Steve.....sounded nice when you left the car park 8)


Sounded nice :confused: :confused: what his twin turbo'd Saab :confused:

It was Colin with the black GD who left the car park. ;) :D :D

jeff
08-04-08, 02:45 PM
never really worked mine out before (Rover 3.5), but I had a run to Devon during the summer total 460 miles.

Just worked out at 27 to the gallon not bad at all considering it I was giving it a bit of welly both there and back. This was better than my old XR4

plod
08-04-08, 03:07 PM
5th gear 60 mph = 13mpg

On a reasonable blat, more like 7...

Miket
08-04-08, 03:09 PM
5th gear 60 mph = 13mpg

On a reasonable blat, more like 7...

Hi Paul, long time no hear from you. :D :D Have you not sold it yet. ???????????????????;)

plod
08-04-08, 03:14 PM
Total change of circumstances Mike, last few years been interesting. Figured the way the property market is, I could have taken the car up to London and still be waiting for a sale. Plus, their market value was way below what I expected.

Thansk for post. All being well, I'll see you at the classic :-D

Miket
08-04-08, 03:36 PM
Total change of circumstances Mike, last few years been interesting. Figured the way the property market is, I could have taken the car up to London and still be waiting for a sale. Plus, their market value was way below what I expected.

Thansk for post. All being well, I'll see you at the classic :-D

Yes will see you at the Classic, will you be taking the Daytona. ;) :D :D

dave
08-04-08, 04:02 PM
Mid 20's mpg from a 350 or 383 stroker and touching or just over 20 mpg from a big block should be acheivable with out too much fuss if you are cruising at steady (Legal) motorway speeds. ;)
Floor it though and you can get them below 6mpg.:shock:

Noel
08-04-08, 04:30 PM
Sounded nice :confused: :confused: what his twin turbo'd Saab :confused:

It was Colin with the black GD who left the car park. ;) :D :D

Ooops......sorry Steve and Colin :oops:

plod
09-04-08, 08:18 AM
Yes will see you at the Classic, will you be taking the Daytona. ;) :D :D

Yupl, should be

KevinW
09-04-08, 01:44 PM
Just had an email from Mike - I had misquoted him slightly, but he said he's had 30 mpg from a SBW on a long cruise.

Kevin

runt
09-04-08, 06:56 PM
Just had an email from Mike - I had misquoted him slightly, but he said he's had 30 mpg from a SBW on a long cruise.

Kevin

That's fair enough Kevin, of course the ability to go everywhere in fourth and fifth given decently clear roads helps, must be many on here whose cars would go 30-50mph in 4 sec in FOURTH; as the original 289 Cobra did.
I passed a 'mimser' in a something or other this week, a whiff of throttle in fourth @ 40 mph, felt like I was going to take off, thought "Thank Christ Stapleford Airfield is close by should I become airborne.."

Paul.:)

dingocooke
09-04-08, 08:19 PM
my old hawk was pretty good on a long run, mid twenties coming back from Cherbourg to Nottm (only 1 1/2 tanks full as I recall) but to be honest who cares about fuel economy in cars like these??? Its like worrying if a call girl is a good cook isnt it???

wilf
10-04-08, 07:26 AM
What is a "SBW" Kevin?

Small Block "whatever"? (teenage girls ride)

Small Block "W*nker"? (I have a candidate in mind :mrgreen:)

Small Block "Wover"? (Mr Ross's car there)

Small Block "Wotsit" (for the man who really doesn't care about engines)

dingocooke
10-04-08, 07:59 AM
S illy B ugger W ilf??????????? :D :D ;-)

wilf
10-04-08, 10:19 AM
Could be, could be. :mrgreen:

lutman
10-04-08, 01:14 PM
5th gear 60 mph = 13mpg

On a reasonable blat, more like 7...


Rock on plod !!
Then again its a monster engine.

KevinW
10-04-08, 01:48 PM
What is a "SBW" Kevin?

Small Block "whatever"? (teenage girls ride)

Small Block "W*nker"? (I have a candidate in mind :mrgreen:)

Small Block "Wover"? (Mr Ross's car there)

Small Block "Wotsit" (for the man who really doesn't care about engines)

meant Small Block Windsor, you know the sort of thing, like the one you posted on clubcobra from that car of yours called a, erm ... credman wasnt it? :-D :-D

wilf
10-04-08, 02:17 PM
Nah, that was a crudman. Before I got the Crendon. :mrgreen:

I though of what you probably really meant : S mall B ore W illy..........:twisted: