Haflinger Fuel Consumption - Larger Bore Engines

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NM_Mogman
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Joined: Wed Sep 05, 2007 9:08 pm
Location: Rio Rancho, NM

Re: Haflinger Fuel Consumption - Larger Bore Engines

Post by NM_Mogman »

TechMOGogy wrote:Try a PM to Shawn (westernair)
He has a big bore engine built by Leo out of Carlsbad, Ca

If I may ask, what was the consensus on the performance differences and fuel consumption between your and Shawn's Haffies? Also, what was the difference between the original motor and the larger as far as power, fun-factor, usability, Offroad performance, etc...?

Regards,

Phil
Heinkeljb
Great Britain
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Re: Haflinger Fuel Consumption - Larger Bore Engines

Post by Heinkeljb »

In theory, the only difference should be in torque. Engine speed should be governed with the governor to 4800rpm Max. Increased torque should mean things like less gear changes, (changes in speed on hills etc.) BUT to be honest i can't see that you will get a huge increase in torque for the relatively small amount of increase in capacity that you can get on these engines. I should think you would be lucky if you added 5~10bhp.

I am sure it would make the Haflinger "feel" nicer to drive as there would be a response from the engine under most throttle movement, but I am betting that it would be at the expense of fuel consumption.
If the engine could be persuaded to have something like a third more power than standard , then you probably would not see any changes in road speed when on "smooth" roads whatever the terrain. Off road would mean less likely hood of stalling if ploughing through thick mud.

Just my thoughts on the matter.

John
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Garrycol
Australia
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Location: Canberra Australia

Re: Haflinger Fuel Consumption - Larger Bore Engines

Post by Garrycol »

My engine no longer has the governor and it really does not need it as it really gets to 4800 rpm (noting the governor will allow it to go to 5200tpm).

My Haffie has the 70kph gearing and the bigger engine with only 90psi (vs 115psi) in one cylinder and 14" wheels has a top speed of 79kph and will cruise at 70kph in favourable conditions. The issue is in lower gears where 4th is still just a tad over 40kph so you have to leave it in 5th until speed drops to 40 on hills. The engine does have the torque to hold 5th but with the increased torque a higher 4th gear would be a help.

In my view more power is not a great help if revs cannot be increased - with standard gearing the only option is to go 14" wheels (brings some stabilty issues) and the 75kph wheel hub gearing so that the extra power and torque can be used. On most main roads I can maintain 5th gear and 60-70kph without over reving the engine - steep highway hills may require 4th.

if you go to the effort of increasing power you need to increase revs so that means careful balancing and other mods that allow rev increases to be safely achieved. If have 87mm bores but I do not know what other mods have been done so I limit revs to about 4500rpm.

My engine has now been tuned (but does have low compression on one cylinder) and it is now only getting 19mpg (imp) in around town driving - noting that Canberra is very car orientated and has little bumper to bumper traffic.

Garry
1973 Haflinger AP700
1977 Landrover FC 101
2007 Range Rover Sport TDV6
1971 Jaguar Series 3 E-Type Conv
1957 Landrover 88" Station Wagon
1957 Landrover 88"
NM_Mogman
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Joined: Wed Sep 05, 2007 9:08 pm
Location: Rio Rancho, NM

Re: Haflinger Fuel Consumption - Larger Bore Engines

Post by NM_Mogman »

Thanks for the info, both of you! I didn't figure that the slight increase would be so much that you would be racing, just mostly wanted to know how it "felt" with the engine mods. Did you ever find out what Shawn was seeing, fuel-wise, with his Haffie? Thanks again!

Phil
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Garrycol
Australia
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Location: Canberra Australia

Re: Haflinger Fuel Consumption - Larger Bore Engines

Post by Garrycol »

NM_Mogman wrote:Did you ever find out what Shawn was seeing, fuel-wise, with his Haffie? Thanks again!

Phil
Not racing - just driving :D

I did ask Shawn about fuel consumption. The Haflinger specification sheet indicates average fuel consumption on road should be 31.6mpg and I am getting 18.1mpg on a good day. For sure the Haflinger figure is probably optimistic and with a bigger carby and engine capacity will fuel consumption will be less but the difference is too great.

Garry
1973 Haflinger AP700
1977 Landrover FC 101
2007 Range Rover Sport TDV6
1971 Jaguar Series 3 E-Type Conv
1957 Landrover 88" Station Wagon
1957 Landrover 88"
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