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300 USA 6CYL

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Hey latley i have seen a bit of resurgence with these engines in the states has enyone here ever had a 300 ? and would the crank be able to stroke a crossflow ? 

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You can apparently stroke a crossflow with offset grinding and a different combination of pistons and rods. The question is why would you? They're already well undersquare. If you need more torque beyond that, a smallish turbo or even a roots blower would fix that while producing more top end power. People go to extreme measures to counter the inherent problems of such a long stroke with the 250 as it is. Adding stroke would exaggerate these issues. The piston speeds would be huge with such a long stroke.

The reason strokers are popular with American V8s us because most of them are well oversquare from factory and have a lot more head room to gain bulk capicity and still keep piston speeds sensible.

 

The 300ci 6 is a different family with a 4" bore and almost 4" stroke

 

 

 

 

 

 

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Yeah they're basically a big-block 6. Everything is scaled-up, including bore spacing. So no, 250 is basically as far as you can go. The Chrysler Hemi 6 was a better design to start with, from a performance point of view. They have 318 pistons for an oversquare cylinder. That's why they can rpm.

The 300 is a torque monster, but the heads have very limited potential for performance. Think of a 400M with 302W heads. That's about the best analogy you could have. Ford never wanted them to make lots of power, just to push farmer Billy Bob along in his F-truck, towing cows to the auction, and do it for a very long time without even thinking about maintenance.

Speaking of bore spacing, some have cut up LS heads and bolted them on, some 4V clevo's, basically people with too much money and spare time.

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Just now, winton said:

If you were keen on the 300 I think you would be better off looking at fitting an xflow head to one. 

Something I'd be interested in myself

If it is possible I should of added

 

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Those truck engines have a v8 bellhousing, they have similar bore spacing to a clevo/windsor/ls so there are some that get around with a couple of cut up v8 head on them, they are a torque monster for what they are. I'll never forget when I was a kid one of my dads mates had an f350 with a tired 300 in it he rebuilt a mild 351 clevo for it and was disappointed with it enough afterwards that he sold the truck. The main reason I wouldn't use one in a falcon is they are as big (if not a little bigger) as a barra (I think other than wiring the barra is an easier swap). Also parts availability over here is not that great for them

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can someone explain why we had so many 4.1 crossys and yanks had heaps of 200 c.i pre crossys,did the yanks ever have a pre crossy 250
Over here, the 6-cylinder was the bread-and-butter powerplant of all 3 big makers. In Falcons, they probably accounted for 90% of all vehicles, give or take, and V8s were a luxury considering the cost of fuel here vs in the States.

Over there, fuel was cheap, so going from the base 200 up to a V8 option wasn't much of a stretch in both purchase price and running cost.

We inherited the Hemi 6 as an abandoned design from Dodge, due to the cheapness of fuel at the time over there. Everyone wanted V8s. They figured that the 318 was a better base engine rather than producing a whole new engine just to replace the slant 6.

The yanks kept with the 200 because they wanted an economy model. There were still lots of cars offering the 250 but nobody bothered to hot them up because they breathe so poorly.

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Sort of on topic, but does anyone here know if a Barra crank will bolt into crossflow? I remember the EF cranks go into certain crossflow blocks (but can be machined to fit into other crossflow blocks?), and I think the Barra cranks can go into 4.0 SOHC blocks?

Reason I’m going down this path is Spool is putting together a 4.2L stroker crank (103mm strike from memory) for the Barra


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Unfortunately for you Micheal, Ford increased the main journal diameter from AU onwards. So unless you get one and then go to the trouble of getting the crank ground down to crossy/e-series size, this won't work.

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There was a very rare xflow alloy head available for the 240/300 6cyl made in the early 90's for the EFi 300's

https://www.ford-trucks.com/forums/1351968-holy-grail-found-on-ebay-4-9l-ford-crossflow-head.html

I can remember enginepower TV show did a built in 2014 made 209hp 310ft/lb with Comp Cams 219@0.050" .456" cam, roller rockers, 390 holley on Offenhouser intake

Part 1

https://www.powernationtv.com/build/73/old-skool-six?episode=EP2014-03

Part 2 with dyno test.

https://www.powernationtv.com/build/73/old-skool-six?episode=EP2014-04

 

EF/XH crank goes straight into 86 DA block, needs 3mm off rear of crank to fit 84DA block(92mm rear seal instead of 95mm) ,80DA-83DA block unsure on machining.

Mains are bigger on AU-FGX engines 2.65" from 2.39", don't know about barra fitting AU SOHC, Barra oil pump is driven direcly from the crank as SOHC is from the timing chain,

Stroking a such a under square engine only makes harmonics worse particularly at hi rpm, there's been a few crossflows stroked to 272 I think they were.

but also evident is destroking such to 3.7lt in SOHC & Barra's. Dynomite XR6 BA turbo(8.25/171) & ex prostock car 10,000rpm(6.8/216). tunnel vison have done a few as well,

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Yeah I've watched those are few times now, must say I was a little dissapointed with the final figure. I was expecting at least 250. Maybe with some port work it could be achieved.

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There longer ALOT heavier and taller than a xflow with less hp. 

 

But people have been putting clevo and LS heads on em for a while. Then you get a custom cam,lifters,pushrods rocker cover,ignition exhaust and cooling.

 

Yes I looked at it as a option but it was going to cost more than my xflow. One upside is the steel crank. Like said above a xflow is only lacking bore size not cubes and forced induction sorts that. 

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Theres more NAT ASP hp potential from the 300cuber but the cost is epic.

 

That said Wazzy made as good as 500hp with his xflow thanks to JB race engines but that would of been at a epic cost too.

 

Issue here is people want and think of a 6cyl as a cheapo thing and expect good hp from em just as cheaply. Speed/power/money rules still apply though. I rate the idea of one though

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I agree, and I'm very surprised with the absence of aftermarket heads for them compared to the hundreds of different SBC and Windsor heads available. Just one casting would do, poured in China but machined in USA. Model the porting off a stout Windsor profile but use stock manifolding. Maybe even make it a crossflow.

With the loyal following these engines have, I reckon folks would be climbing over each other to put their money down.

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There longer ALOT heavier and taller than a xflow with less hp. 
 
But people have been putting clevo and LS heads on em for a while. Then you get a custom cam,lifters,pushrods rocker cover,ignition exhaust and cooling.
 
Yes I looked at it as a option but it was going to cost more than my xflow. One upside is the steel crank. Like said above a xflow is only lacking bore size not cubes and forced induction sorts that. 
You really have to look pretty hard for the forged steel crank versions. They were a truck division part, only found in medium and heavy trucks like tippers and cement mixers.

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can someone explain oversquare and under square bore
Oversquare: piston is wider than stroke length
Undersquare: stroke is longer than piston diameter

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