The straight 8 was great and talk about power; but, boy it was a mile long too!

 

You just put your finger on the problem here. The only real problem with inline engines of more than about 4 cylinders is that after you get to about 6 cylinders they're really getting to be long. That means they require a really long engine compartment, and that means a longer frame, and a longer body and that means a greater overall vehicle weight. That works against you when you're a designer trying to get every one of your vehicles to give the best possible fuel mileage. That's one reason why most 6 and 8 cylinder engines today have their cylinders arranged in a V rather than in a line.

Another reason is that a V6 or a V8 can, with a few small tweaks, be packaged as either a transverse or a longitudinal engine, which means it can potentially be used in both 2 and 4 wheel drive light trucks as well as front wheel drive passenger cars. To prove the point, Cadillac is doing this with their Northstar V8 engines. On the other hand an inline 6 or 8 of a decent size is generally too long to be used transversely in most cars.

As for overhead cams, there's actually no reason to shun them. There's nothing about either an SOHC or DOHC design that prevents the designer from tuning the engine for for either stump-pulling low end torque or high rpm horsepower. Use the right cam profile and such and you can make an OHC engine produce either one.

In fact, given variable valve timing (like that in GM's Vortec 4200 inline 6 that I mentioned in a previous message) you can actually get a bit of both. The Vortec 4200 reaches its peak torque of 275 ft-lbs at 3600 rpm, but at least 90% of that amount is available from 1600 to 5600 rpm. That's 247 ft-lbs of torque or more over that entire range. Not too bad for an engine displacing about 254 cubic inches running on regular unleaded, eh?



To give you folks some perspective here, to equal that sort of performance on a per-cubic-inch basis the 300 would need to produce 292 ft-lbs of torque or more over that same range, and it would need to have a peak of 325 ft-lbs of torque at 3600 rpm. I may be mistaken, but I don't think a stock 300 ever did anything remotely like that.

Now before you guys all think I'm a GM shill, I want to mention that there are some things about the Vortec 4200 I don't like all that much. For one thing it has a "plastic" intake manifold. Now mind you, it seems to work just fine and it's light as all heck, but, well, it's got to be one of the plug-ugliest intake manifolds I have ever seen. I'm also not as confident about its long term durability as I am about that of the Ford 300. I gather they had some problems in the earliest engines (something about the cylinder liners, I think) and that doesn't exactly inspire much confidence. But time will tell. They might get it sorted out.

I wouldn't look for Ford to resurrect the 300, myself. If they go back to building inline sixes it'll almost certainly be an all new engine based on many of the same general design ideas used in their new "modular" V8s. That means overhead cams, crossflow head design, as well as aluminum heads and possibly aluminum blocks, too. They might even share a lot of the same internals -- valves, pistons, valve-train parts, etc. -- to reduce tooling and design costs.

Assume, for the sake of argument here, that they build it based on parts from the 5.4L TRITON® V8 and that they gave it similar dimensions for bore, stroke and such. That means it would displace about 247 cubic inches, and that it would put out about 225 HP and about 270 ft-lbs of torque if it had tuning like the V8. (It probably wouldn't, actually, but nevermind that here.)

That'd be a nice engine for a mid-sized pickup truck like a Ranger, but they already have a 4.0 liter V6 for that line and I don't see any reason to think they're likely to replace it anytime soon with an inline 6. They'd have to redesign the entire truck to do so because of the longer engine, so it'd have to wait for that to be feasible and it'd have to be a part of the replacement plan right from the beginning like it was for GM's new midsized SUVs.

Frankly, unless the market suddenly starts to shift toward inline 6s and away from V8s (which isn't at all likely right now) I don't see Ford making that change. It looks to me like Ford truck lovers who want an inline 6 will need to buy an older one for now as well as for the foreseeable future..

It goes without saying that I'm mostly just speculating here, of course, so, well ... ya never know.

 

I've bought several new ford cars from our local Ford Dealer, he's ask a couple of times when are you going to replace your old pickup? I've told him just as soon as Ford brings back the inline six ! He's told me that Ford will never bring back yesterdays technology and try's to push the 4.2 on me, this year I almost went for it, with the rebates on the Heritage Model makes Great deal, but I'm holding out for the inline.

 

Ford is only going to make gas engines based on there modular design that is all they have tooling for. The 4.2 is nothing more that the 5.4 with two cylinders missing. This is a bean counters world and they are ging to mass produce engines from the same tooling they will not invest money for tooling to build a inline 6. Overhead cam engines will never produce enough torque to be usable in a truck that has to work.

 

Here's what I have found about the fuel mileage on a 1988 f150 2wd, 300 i6, man. 5 speed. 11.1 greenhouse gases emissions (tons/year) and 16/20 mpg.

Now here is a 2005 f150 2wd, 4.2 v6, man 5 speed. 11.3 greenhouse gas emissions (tons/ year) and 15/20 mpg.

I used 1988 f150 because it was the year of my truck and they both have fuel injection (1988 and 2005). All this info can be found at http://www.fueleconomy.gov/

So my vote goes to bringing back the big block I6 so us that like real trucks can have something that makes its power down low, After all it is less polluting than smaller v6.

 

It seems that everyone on here already has there truck. I'm looking hard for a truck with a 300, maunal transmission and 4wd. I've only seen a few for sale and either they are trashed or they want way to much for them. I would like to get my hands on a spare engine too so that when I am done with school I can see what they are capable of with all the tweeks. I know the I6 although not built for acceleration can set a good pace and can out pull a 302 and has a chance against the 351. As I read through this thread it was half about the 300 and half about the sociaty that cares more about looks and speed then actually being usesful.

Ok, enough ranting for me. Truck shopping is getting to me since I can't buy it new and I can't find it old.

 

Well even if the 300 is a dead issue in new trucks I at leastwould like to see Ford design a newer I-6. With technology the way it is they can come up with enough ponies and torque in a smaller engine. I would buy that engine in my next truck.

 

What I would really like to see in the light trucks is small diesel 4cyl for Rangers a 5 or 6 cyl for f150's

 

Neocowboy,
Find the year/model truck you like for a good price and then drop in a 300 I-6 if it doesn't already have one. Easy swap in most cases. Hint, everything pre-79 is real easy to do.

 

300 is the best motor. period. with technology of 2004, i bet ford could make a 300 i6 to outperform the 5.4's. the 5.4's are weak. i bet a i6 could be a better performer, better gas, and better durability and ruggedness of a V-8. especially with modern technology.

 

I have dreamed of this many a time. Would love a 400 straight six in my motorhome.

Might take a Ranger pickup if I could get a OHV inline 4, which they used to have at one time. Problem is they just don't make a big enough 4 banger. I think they need a 200 cid job (that would be about 3.3L for you foreigners ).

 

Modular Engines are the thing now eh?

Then why not take the I-4 Engines...Increase the bore, stroke, and block deck height. Slap two more cylinders on them...use the ford version of VVT or (VTEC) with overhead cam technology and make something in the 300-400 cubic inch range?

Or if that isn't possible they could use the tooling from the 5.4 Modular...it would take a bit of work but it isn't entirely impossible to build a 6 like this. Instead of using the V based layout of the block, just use one row of cylinders, tack two more on and "straighten" the block. If they can take the Mod setup and build V10's, i'm certain that its no stretch of the imagination to retool them to produce an I6.

 

I want a Ranger with an inline four made from one bank of a 460 V8!

 

Well, by increasing the bore, stroke and deck height (and most likely the bore centers if you're increasing the bore size by as much as you'd need to for you to get to a decent total displacement) you're effectively designing most of an entirely new engine, or so it seems to me. Let's look at option 2 instead.



If you leave the bore and stroke dimensions identical to those of the 5.4 liter engine you end up with something like a 4.0 or 4.1 liter inline six. A few minor tweaks to bore and/or stroke could probably get you to 4.2 or slightly more, perhaps and I think thats probably big enough for our purposes here, especially if they incorporate some sort of variable valve timing to allow a lot of low-end grunt and mid-range torque without having to give up the high rpm horsepower the "car people" seem to look at when buying an SUV or light truck for the family.

If they do it right they should be able to come close to matching the output of GM's Vortec 4200 (roughly 275 HP and 275 ft-lbs of torque with a fairly flat torque curve) and that's not so bad, is it? It's certainly better than either the current 4.0 V6 they're using as the high end engine in the Rangers or the 4.2 V6 they're using as the low end engine in the current F150s.



Is that the sort of thing you think "truck people" would go for?



If not, well ... Hmmm ...

The stroke on the 5.4 engine is already pretty darn long (4.17 inches) so I think a bigger bore might a better way to get more displacement. The 5.4's bore is 3.55 inches, but if you pop it out to the same bore as the old venerable 300 (4.00 inches) you get an engine displacing about 314 cubic inches, which is about ... um ... 5.2 liters? This would probably require a larger bore center, but it'd really make for a SERIOUS inline 6, wouldn't you say? With that much displacement you could get around 300 ft-lbs of torque without even breaking a sweat and more than enough horsepower, too.



Only one possible problem with this. Will this new, cool, monster inline 6 fit between the firewall and the radiator of the current trucks Ford is building or are we going to need a new F150 design to accomodate it?

 

Keep in mind that the profile of the cam(s) not the location, is what's important. If that weren't the case, then alot of over the road diesel trucks would be high winding cammers instead of low rev grunt motors. The Series 60 Detroit is one suck example of big diesel OHC engineering, and it peaks at 2,200 RPM and the party is over at about 2,600.