Rpm range
#2
10-19-2011, 06:35 PM
Most people who have the 300's and most people who've built the 300 inline-6 agree that 2000 rpm is where peak torque is made, and 3000 rpm is right around where peak horsepower is made. The power curve drops off significantly past 4000 rpm, and if you go past 4500 you risk over-revving the motor, floating valves, and other problems.
The reason a 300 can't rev high is it's long stroke. These motors have a 4'' bore, with a 3.98'' stroke, and using 6 pistons, that makes the 3.98'' stroke a big stroke. If it was a 302 with a 4 inch bore and a 3 inch stroke with 8 pistons, you could go up safely to around 4800-5000 rpm because the piston strokes are an inch shorter. Past that, I'd want the motor balanced and better flowing heads.
The key to remember here, is that the 300 doesn't rev high safely because it doesn't have too. All of it's power is on the down low, which is where you should keep it when having fun.
Peace.
The reason a 300 can't rev high is it's long stroke. These motors have a 4'' bore, with a 3.98'' stroke, and using 6 pistons, that makes the 3.98'' stroke a big stroke. If it was a 302 with a 4 inch bore and a 3 inch stroke with 8 pistons, you could go up safely to around 4800-5000 rpm because the piston strokes are an inch shorter. Past that, I'd want the motor balanced and better flowing heads.
The key to remember here, is that the 300 doesn't rev high safely because it doesn't have too. All of it's power is on the down low, which is where you should keep it when having fun.
Peace.
#4
10-19-2011, 06:57 PM
Postmaster
#5
10-19-2011, 06:59 PM
Postmaster
#7
10-19-2011, 07:08 PM
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#8
10-19-2011, 07:27 PM
Postmaster
Same as you'd get 8,000 out of a sbf. Balanced, lightweight rods & pistons, big cam, big head work. Maybe laughing gas or a turbo. Or both. Speed is just a matter of money.
Check out Mighty 6 on youtube. It's a 292 Chevy...but I think he's pumping 800hp at the rear wheels.
With the stock cam you'll have to shift before you can do any damage. Unless you're determined. I've never matted mine for long in high gear but it's not pulling much past 4,500 anyway.
Check out Mighty 6 on youtube. It's a 292 Chevy...but I think he's pumping 800hp at the rear wheels.
With the stock cam you'll have to shift before you can do any damage. Unless you're determined. I've never matted mine for long in high gear but it's not pulling much past 4,500 anyway.
#9
10-19-2011, 10:06 PM
#10
10-19-2011, 10:29 PM
Post Fiend
#11
10-20-2011, 08:43 AM
With the stock cam and valve springs, you will run out of cam long before you break something, unless you do something silly like rev it in neutral.
According to The Frenchtown Flyer, a former Ford engineer who was involved in the 300 program and who has been racing 300's for decades, the stock rods have a safety margin of 2.7 at 4500 RPM.
If you have the stock YF or YFA carb, you will run out of air flow before you break anything.
Bottom line: If the engine does not have some mechanical problem and you don't do something "silly-stupid" with it, you aren't going to hurt it.
According to The Frenchtown Flyer, a former Ford engineer who was involved in the 300 program and who has been racing 300's for decades, the stock rods have a safety margin of 2.7 at 4500 RPM.
If you have the stock YF or YFA carb, you will run out of air flow before you break anything.
Bottom line: If the engine does not have some mechanical problem and you don't do something "silly-stupid" with it, you aren't going to hurt it.
#12
10-20-2011, 10:44 AM
Lead Driver
#13
10-20-2011, 06:34 PM
The reason a 300 can't rev high is it's long stroke. These motors have a 4'' bore, with a 3.98'' stroke, and using 6 pistons, that makes the 3.98'' stroke a big stroke. If it was a 302 with a 4 inch bore and a 3 inch stroke with 8 pistons, you could go up safely to around 4800-5000 rpm because the piston strokes are an inch shorter. Past that, I'd want the motor balanced and better flowing heads.
The key to remember here, is that the 300 doesn't rev high safely because it doesn't have too. All of it's power is on the down low, which is where you should keep it when having fun.
Peace.
Don't tell the guys that race them this it just might ruin their day!!
Build it right!
Here's FrenchTown Flyer's, I believe he said he's usually turning around 7200 rpms thru the timing lights.
2010 Indy ET Finals Drag Racing Ford Six - 15 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 14 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 13 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 12 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 11 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 8 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 7 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 6 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 1 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 5 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 4 - YouTube
2010 Indy ET Finals Drag Racing Ford Six - 2 - YouTube
#14
10-21-2011, 04:35 PM
