# 300ci inline six

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#### jumpinjan

##### Well-Known Member
That Ford engine is old technology. The new auto engine technologies are lighter, more torque & HP, increased longivity and would just be as plentiful give some time. As an example, I have seen complete 4.2L Vortecs go on the average of $500-$600, and these are from roll-overs or rear end collisions.
I like to look ahead and not look back at old technology.
Jan
(also to mention, every airplane will fly better with less weight. Just because the Fok D7 had a 700lb engine, doesn't mean you also use a heavy engine)

#### Dan Thomas

##### Well-Known Member
I've rebuilt a couple of 300s. They're awfully heavy, and there's noplace for the oil to accumulate in the case for scavenging. It would have to drain down the oil channels that usually drain the rocker cover area atop the head, and that's on just one side. The other side would channel oil into the cylinders and cause hydraulic lock.

The inverted aircraft engines have their cylinders extending into the case to keep oil from draining into the cylinders but they still use a lot of oil and foul their plugs. The Gipsy I used to fly in an Auster used between a pint and a quart per hour. It had a 12-quart tank, just to be sure.

The other issue with the Ford would be crankshaft strength. It likely wouldn't tolerate the gyroscopic loading introduced by the prop.

As a truck engine, it's wonderful. I put one in my '51 International and it will climb trees.

Dan

#### ddoi

##### Member
I hear you jumpinjan - lighter is better. I'd just like to know how heavy the 4.9 really is. A few reasons for my curiosity: low rpm torque (for direct drive), 2 bearings on each side of the rod journals, gear driven cam, ideally balanced I-6 layout, stock/readily available distributors (Hall effect), low parts count/complexity (1 cam, 12 valves), ease of conversion (ECU not required for variable valve timing, direct injectors, etc.), and durability.

Dan, I hear you too. Another bearing to take gyroscopic loads is the way to go (IMO) with almost any auto engine aero conversion. That could be in a prop extension w/bearing holder or a PSRU.

My mind isn't made-up... just researching before crossing possible engines off the list. Thanks for the input!

Dai

#### Dan Thomas

##### Well-Known Member
I'd estimate the engine at around 500-650 lbs with the cast flywheel and manifolds. Might be able to reduce that with headers and an aluminum head. The crankshafts in long engines is far heavier than in shorter units like the V engines, and its length requires much heavier construction for stiffness.

250 ft-lb @ 1600 RPM is only 76 hp. The engine is designed to produce around 150 hp at 3800. At typical prop speeds of about 2700 I wouldn't expect a lot beyond 110 hp or so. At 600 lbs, that's a very poor hp-to-weight ratio.

Dan

#### ddoi

##### Member
Dan, thanks for the response - I'll take it into consideration.

In case anyone's interested, there's an article, "Flying Truck Engines", in the August '93 Sport Aviation. It's written by an engineer and has an interesting/insightful perspective on converting car/truck engines for airplanes.

Thanks, Dai

#### jumpinjan

##### Well-Known Member
I would like to read a copy of that article
Jan

#### K-Rigg

##### Well-Known Member
edit never mind, i thought i found it.

#### ddoi

##### Member
Jan,

I sent you a private message.

Dai

#### ddoi

##### Member
Just to beat a dead horse... I found a published weight for the Ford CSG649 (industrial version of 4.9 I-6) long block is 473 lbs. Dan, your estimate was right.

#### Dan Thomas

##### Well-Known Member
Just to beat a dead horse... I found a published weight for the Ford CSG649 (industrial version of 4.9 I-6) long block is 473 lbs. Dan, your estimate was right.

I think the long block includes the head but not manifolds or anything else.

Dan

#### Old Jupiter

##### Active Member
Go to the Ford Six Performance site, then Advanced Search, and looks for threads by a member named Von Writter. He is building a full-size Fokker D-7 replica and getting ideas for powering it with a Ford 300-six. I think he is pondering a centrifugal supercharger, which would be pretty close to period-correct, and boost power-to-weight considerably, even at lower crank rpms. It does increase complexity, however.

Another member (who hasn't posted in some time) calling himself 6-Banger Bill was cutting up aluminum Chevy heads and welding them to make lighter, better heads for the 300-six. Now part of his goal was better port-flow and performance at higher rpms than we want an airplane motor to turn. But the lighter weight is certainly desirable.

Keep in mind (anybody; I'm not pointing at anyone) that an "auto engine CONVERSION" suggests, at least to me, something more than putting a car engine into an airplane with minimal alterations. The Ford Big Six was a capable auto engine right from the factory. It could be a relatively quite and reasonable engine for some kinds of airplane, like that Fokker replica, WITH a lot of upgrading and alteration. My feeling is that whether any particular engine was a good car engine is irrelevant here; the point is, can it be made into an acceptable airplane engine. The silliest piece of advice I ever read was by Richard Finch who suggested that you might see whether you want a particular car engine in your airplane by taking a test drive in a car that has that engine!

About crankshafts, the 300-six as used in bigger trucks and maybe some pickups had a forged crank. Again, search FSP for info on this.

An aluminum intake manifold, either the factory efi intake or one of the aftermarket intakes for carburetion, will save some weight.

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#### ddoi

##### Member
Thanks Smitty. I've been following that Fokker DVII build - can't wait to see and hear that thing running. The aluminum heads are interesting too - I'll search for 6-Banger Bill. Making a cross-flow head will be quite a feat. Really, thanks for the input and advice, it's not taken lightly.

#### mel

##### Member
Well everyone I wrote Edelbrock about AL cross flow heads for a 300 ci ford. There reply was 'IT WOULLD COST \$50,000 for tooling to even start.' Maby if everyone interested in the heads would write them a e-mail they might be inclined to make some.

#### MKIV

##### Active Member
The 300 & 240 cu in Ford Inlines must share the same cyl centerlines as the Ford 289/302/351 etc, because I read an article many years ago about cutting a pair of Boss 302 heads in half & middle to make an all out 6 banger. They used cyls 2&3 from one head in the center with cyls 1&2 on one end & 3&4 on the other to make one head for a 6 cyl. Now I cant remember if its only each pair of cyls (1/2-3/4-5/6) are at the std Ford spacing of 4.38" & a slightly larger dimension between pairs ( that would be handy if welding) or all at 4.38".
Plenty of Ford V8 Alloy heads around now if you want to try & they are All crossflow, & fairly sure the head bolts line up as well.
You should also remember that putting Chev stuff on Fords ruins the reliability factor...