[Healeys] fuel consumption

Sun Jul 3 15:20:47 MDT 2022

My BJ8 was rebuilt 2 summers ago with 20 over on the cylinders. For break in I would drive the car at 40 to 50 mph on the Tamiami Trail with few stops for 40 miles.  I had the speedo rebuilt for the next 500 miles and moved the needle to 60 mph.  During these first trips, the fuel consumption was 12 mpg approximately.  When I left Florida, I checked the fuel consumption, and it was between 14/15 mpg US Gallon with 2500 miles on the speedo.  In owning this vehicle for 40 years never got much over 15 mpg on long trips.   Nevertheless, will continue to watch the consumption next winter.  Oh by the way, I use unleaded and no pinging.

Bob Begani

From: Healeys <healeys-bounces at autox.team.net> On Behalf Of David Nock via Healeys
Sent: Sunday, July 3, 2022 1:59 PM
To: llennep at verizon.net
Cc: healeys at autox.team.net
Subject: Re: [Healeys] fuel consumption

If your fuel problem started after the engine rebuild, there is a problem in the rebuild. A new engine may get a little lower fuel mileage at first but after the first hundred miles or so the engine is what it is going to be.

I would recommend checking the ignition timing, carb needles, float levels, and valve adjustments. If you increased the compression 10:1 then there may be the reason. 

I would double check the cam timing. It is very easy to set wrong, and can be compensated for by advancing the timing. But you will have limited power and poor fuel economy.

David Nock

British Car Specialists

On Jul 3, 2022, at 9:51 AM, llennep--- via Healeys <healeys at autox.team.net <mailto:healeys at autox.team.net> > wrote:

Thanks Bob.  Useful info.

Sent: Sun, Jul 3, 2022 11:17 am
Subject: Re: [Healeys] fuel consumption

A friend and I used to take a long road trip--up to 5,000 miles--in my BJ8 every year for over 20 years. He checked our mileage at every fuel stop--useful if your gas gauge goes on the fritz--and I checked the odometer against the roadside markers (it was spot on). Through three engines the mileage stayed very nearly the same: 15MPUSG in stop-and-go city driving, best I got was 25 on 'slow' (55MPH), flat highway driving (eastern Oregon, when the troopers used to enforce it) and at freeway speeds (70-75MPH) I got around 18.  When I went from the 3.9 rear end to a 3.54 I expected a mileage 'bonus,' but at most I got a tenth or two better MPG.

29.6 miles per USG is extraordinary; these conversations come around every few years and no on ever claimed much more than I was getting. 

On 7/2/2022 8:48 PM, m.g.sharp at sympatico.ca <mailto:m.g.sharp at sympatico.ca>  wrote:

Hi listers,  As you might recall, I just had the engine rebuilt on my BT7 last year.  I only have 670 miles on it so far.  My fuel consumption seems exceptionally high.  I have just checked on one fill up, and need to repeat to be more certain, but on the last tank I got an awful 10.1 miles to the Imperial Gallon (14.8 miles/US gal).  I used to get about double that.

I have checked the tune on the carbs using the usual method and checked it with a quick plug check (I have yet  to do a proper plug chop), and if anything I think I am running a bit on the lean side.  The exhaust seems good, just rich when the choke is on, however the engine does “hunt” a little when at idle.  It runs beautifully otherwise.  No fuel leaks at all.

My questions:  1) what are others getting for fuel consumption? And 2) any thoughts on how to improve it?

Thank all - Mirek

_______________________________________________
Support Team.Net <http://team.net/>  http://www.team.net/donate.html
Suggested annual donation  $12.75

Archive: http://www.team.net/pipermail/healeys http://autox.team.net/archive/healeys

Healeys at autox.team.net <mailto:Healeys at autox.team.net> 
http://autox.team.net/mailman/listinfo/healeys

Unsubscribe/Manage: http://autox.team.net/mailman/options/healeys/llennep@verizon.net

_______________________________________________
Support  <http://team.net/> Team.Net  <http://www.team.net/donate.html> http://www.team.net/donate.html
Suggested annual donation  $12.75

Archive:  <http://www.team.net/pipermail/healeys> http://www.team.net/pipermail/healeys  <http://autox.team.net/archive/healeys> http://autox.team.net/archive/healeys

 <mailto:Healeys at autox.team.net> Healeys at autox.team.net
 <http://autox.team.net/mailman/listinfo/healeys> http://autox.team.net/mailman/listinfo/healeys

Unsubscribe/Manage:  <http://autox.team.net/mailman/options/healeys/healeydoc@sbcglobal.net> http://autox.team.net/mailman/options/healeys/healeydoc@sbcglobal.net

David Nock
British Car Specialists
Stockton Ca   (209) 948-8767
Specializing in parts, repairs and the restorations on all British Cars since 1957

www.britishcarspecialists.com <http://www.britishcarspecialists.com> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20220703/f3435aa9/attachment.htm>