62Ranchero200
Famous Member
Greetings Ford Six Fans,
Five years ago, I dynoed my aluminum head 250 when it was barely broken in. The best results were:
140 HP
187 ft-lb torque
Since then, I have made the following changes:
* Swapped out the DUI for a DS2 (custom curved by wsa111) with an MSD 6-AL
* Swapped out the C-4 for a T-5z
* Swapped out the chrome top 13" air cleaner for a K&N filter top high flow 14" air cleaner
Over the last week or two, I adjusted the valves, changed the plugs, went from a #6.5 PV to a #5.5, and went from #70 jets to #71.
Today's best results were:
157 HP
221 ft-lb torque
That's an increase of 17 HP and 34 ft-lb of torque. Most of this is undoubtedly due to the C-4 to T-5 swap.
I found a magazine article where a stock 170 (the Ranchero's original engine) was putting down about 50 HP to the rear wheels - so I've tripled the Ranchero's RWHP compared to when it was new. I also found a CI dyno article where a nearly stock 250 was putting down about 75 HP to the rear wheels - so I've doubled the 250's RWHP.
I also did a pull without the air cleaner, it didn't change the HP or torque readings, so it seems that the K&N air cleaner is not any restriction at all (at least, on a dyno pull with the hood up). The dyno's AFR shows that I'm a bit rich at WOT, so I should be able to improve by using slightly smaller jets for the PVCRs.
I plan to swap out the 272/272/108 cam for a 280/280/108 cam and mill the head to gain about a point of compression. Once that combo is sorted out, I have a Holley 4-V carb that I can use to replace the Holley 2-V carb that I have now.
Thanks
Bob the Builder
Five years ago, I dynoed my aluminum head 250 when it was barely broken in. The best results were:
140 HP
187 ft-lb torque
Since then, I have made the following changes:
* Swapped out the DUI for a DS2 (custom curved by wsa111) with an MSD 6-AL
* Swapped out the C-4 for a T-5z
* Swapped out the chrome top 13" air cleaner for a K&N filter top high flow 14" air cleaner
Over the last week or two, I adjusted the valves, changed the plugs, went from a #6.5 PV to a #5.5, and went from #70 jets to #71.
Today's best results were:
157 HP
221 ft-lb torque
That's an increase of 17 HP and 34 ft-lb of torque. Most of this is undoubtedly due to the C-4 to T-5 swap.
I found a magazine article where a stock 170 (the Ranchero's original engine) was putting down about 50 HP to the rear wheels - so I've tripled the Ranchero's RWHP compared to when it was new. I also found a CI dyno article where a nearly stock 250 was putting down about 75 HP to the rear wheels - so I've doubled the 250's RWHP.
I also did a pull without the air cleaner, it didn't change the HP or torque readings, so it seems that the K&N air cleaner is not any restriction at all (at least, on a dyno pull with the hood up). The dyno's AFR shows that I'm a bit rich at WOT, so I should be able to improve by using slightly smaller jets for the PVCRs.
I plan to swap out the 272/272/108 cam for a 280/280/108 cam and mill the head to gain about a point of compression. Once that combo is sorted out, I have a Holley 4-V carb that I can use to replace the Holley 2-V carb that I have now.
Thanks
Bob the Builder