F.5 head on 2F engine

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flx said:
It means you already have 3.7 ratio diff, with 4.1 diff we are already a touch above 3000rpm at 70mph.
80mph should be ~3500rpm on mine (with 7.50R16 tires) but it's doing fine. Noisy but engine is fine at this speed, it's a L6 it needs to run from time to time.
But anyway, no tachometer + ear plugs = no worries :cool:

Obviously if it's your daily and doing a lot of miles every year it may be a different story. Wouldn't say no to a 5-speed if it was an easy swap and keeping the originality of the truck (but it's not on a 1974).
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Nope, 4.10 gears with 33 inch tires.
 
flx said:
Not sure what Kingsbury grade is but I regularly take a Freeway with multiple 6% ascents and my F.5 is fine accelerating up to the max speed of 130kph (~80mph) in 4th gear, as long as I am already at a speed that allows to open the secondary body of the carburetor (I think it's around 50mph in 4th).

Done this multiple time, stuck on the right lane behind a truck at ~55mph in an ascent, pressing the gas all the way down, the secondary opens (in one shot on a F carb) and puts a big kick all the way to 80mph, which helps a lot to insert on the passing lane with the flow.

For driving a long time at stabilized speed it's happier at ~70mph.
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I think your carburetor has mechanical secondary function. Discovered my secondary diaphragm wasn't working. Replaced it for a large improvement.
 
BullHab said:
I think your carburetor has mechanical secondary function. Discovered my secondary diaphragm wasn't working. Replaced it for a large improvement.
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Yes, mechanical secondary with a valve on a F. When the valve suddenly open you get a big kick and engine change sonority, not refine control of power but definitively fun 😄
 
Just out of curiosity: Where could I get a cylinder head like this one (60051)?

And how much would such a head cost approximately?

I think you can forget about finding one in Germany...
 
Landcruiserfj45 said:
Just out of curiosity: Where could I get a cylinder head like this one (60051)?

And how much would such a head cost approximately?

I think you can forget about finding one in Germany...
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Good question. Mine came with the truck. The previous owner made this swap. But if you can find an F engine from 1974. Here in the U.S., they occasionally show up on the market place.
 
Hello,

I've been thinking about taking my cylinder head (61030) to an engine specialist to have it ground down by 2 mm.

That way I can go from 16 mm on my cylinder head to the 14 mm on the 60051 head.

Theoretically, that should be doable, right? What do you think? 🤔🤔

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Its a tractor not a F1. Higher compression needs higher octane and cost more plus is harder to make/find but that's just me and I support people that make it theirs.

I like turbo chargers - cheap effective - no such thing as turbo lag on a tractor, F1 yes! I designed a no waste gate unit that fed air to the filter housing which regulated the pressure by flat springs on the can.
Super chargers can work too. At one time my dad wanted me to do an electric super charger for power burst or high altitude running.
 
Landcruiserfj45 said:
Just out of curiosity: Where could I get a cylinder head like this one (60051)?

And how much would such a head cost approximately?

I think you can forget about finding one in Germany...
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Be careful that in Europe we didn't get dome piston as far as I know (at least not on the F.5 in 1974). So mixing a US head with an Europe block you would need to be very careful you have matching chamber/piston style.

I think Dunkane on this forum, which is in France, found an original F135 for his 40 so will probably be selling at some point the F155 F.5 that is inside currently... but it's fully working F.5, not just a head.
 
Landcruiserfj45 said:
Hello,

I've been thinking about taking my cylinder head (61030) to an engine specialist to have it ground down by 2 mm.

That way I can go from 16 mm on my cylinder head to the 14 mm on the 60051 head.

Theoretically, that should be doable, right? What do you think? 🤔🤔
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In theory, it should work, but read more before trying it. I believe some people have already done it here, though. Don’t take my word for it.

UGA2018

Thread '2F head rebuild threads'

I'm planning to rebuild my head in the next few months and I want to read up as much as possible. I can't find anything in the FAQ section for the 60's or 40's that seems to be the definitive guide to rebuilding the head.

Other than the FSM can you point me in the direction of any threads that would be good reads before I jump into this?

Others build threads or a how to thread?

Thanks MUD!

P

Thread 'Milling Head, its effect on compression ratio?'

When doing the head gasket, if the head is milled say 0.010" or 0.015", what will the resultant compression ratio be?

Thanks!
 
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