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MPG & Oil Pressure

1965AH3000

Freshman Member
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Has anyone checked the gas miliage on a BJ8? I checked mine yesterday, and at 65 - 70 MPH Highway I got 20 MPG. Is this about average? Also at 65 MPH, hot motor, 90 Deg. outside Temp, I was reading 32 PSI oil pressure crusing, 20 at Idle. How does this sound?
 
Both look ok to me, my 65 BJ8 does between 20mph and 25 on a long run. Oil pressure looks fine, cold is usually around 55 on mine, just over 40 cruising hot and around 25 at idle. Engine rebuilt about 5000 miles ago.
Ian
 
I just finished the first 600 mls after rebuild
Mileage after latest fillup 11 gallons for 235 miles
Have to change oil first to see pressure with 20W50 oil (will use VR1)

Hans
 
:iagree:

Sounds about right to me too---Keoke
 
I usually get 21-22mpg on my BJ8 at 65-70mph. Difference could be fuel mixture setting, tire pressure, weight in car, etc. Also, I have a 3.54 rearend which might help a little (not as much as you might think, though).
 
My Phase 1 BJ8 would only get about 20 mpg, especially over 60 mph. Before or after rebuild. Could squeeze 21 or 22 mpg out of it if I drove carefully and kept it to 55 mph, but that wasn't any fun.

Had triple 2" HD8s on it for a while and got the fuel mileage up to nearly 27 mpg, but I took those off the BJ8 to put them on the BT7. Can't say how that's going to work out. But then, who cares?

My MGC GT with the Special Tunings front air dam and 3.7:1 axle got up to 27 mpg at around 70 mph.

C Ya,
Mark
 
Temp. reading was 180 steady. I am thinking of trying a leaner needle. My exhaust pipes are black. Not overly sooty, but I want to strive for a medium grey.
 
Wow, since new and with increased compression, my BJ8P1 could only get 17 MPG on premium gas in OD. I know I run a little rich, however, I didn’t think it was that bad…no smoke out the pipes. Since I do wind the engine quite tight and have higher than normal compression, I thought that running a little richer would help not burn the pistons.

All the best,
Ray (64BJ8P1)
 
I just got 15 mpg including two nights of cruising (stop and creep) on Woodward ave. During Dream Cruise week. I am running rich. I can start without the choke on a warm day with a cold engine.
 
Hey Mark-

How's that work, you got better mileage when you had triple 2" SU HD8's.

For what it's worth, I get 8 mpg with with triple 2" SU HD8's on my race car at speed and the best I've got in my street BJ8 is 23mph.
 
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