Again it’s not a big deal with smaller displacement strokers. However, for large strokers since the block is constant, the larger the stroke the more you run into those issues ie wall load (usual issue) and stroke pulling the piston completely out of the cylinder bore (not common and other failures would have to occur) if it throws the motor out of balance at high RPM.
68 Fastback Restomod project thread
- Thread starter *TK*
- Start date
Again it’s not a big deal with smaller displacement strokers. However, for large strokers since the block is constant, the larger the stroke the more you run into those issues ie wall load (usual issue) and stroke pulling the piston completely out of the cylinder bore (not common and other failures would have to occur) if it throws the motor out of balance at high RPM.
Maybe I’m missing the point, but literally none of that has anything to do with RPM limitations
DP
That thing is beautiful and sounds incredible, congrats.
He said it was a typo, 9000rpm.
-J
-J
Reading co.prehension lol....
I wasn’t able to be there but the guys sent me the dyno video and final figures for wheel HP/TQ. It made several pulls today with the best being:
498 HP
550 TQ
For some contrast the motor made these figures on an engine dyno (at the crank) when it was built:
624 HP
545 TQ
Inherent to a stack injected stroker motor, under load the motor traded HP for TQ. Drivetrain powerloss (both HP&TQ) is always certain, usually around 15% less (this is debatable yes) from the crank. So the fact that the motor lost 126 HP but picked up 5 ft-lb TQ is pretty crazy.
Adjusted figures for crank output using 15% loss would roughly be:
572 HP
632 TQ
We’re going to do some more fine adjustments tomorrow and see what happens. I couldn’t be more happy with it.
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498 HP
550 TQ
For some contrast the motor made these figures on an engine dyno (at the crank) when it was built:
624 HP
545 TQ
Inherent to a stack injected stroker motor, under load the motor traded HP for TQ. Drivetrain powerloss (both HP&TQ) is always certain, usually around 15% less (this is debatable yes) from the crank. So the fact that the motor lost 126 HP but picked up 5 ft-lb TQ is pretty crazy.
Adjusted figures for crank output using 15% loss would roughly be:
572 HP
632 TQ
We’re going to do some more fine adjustments tomorrow and see what happens. I couldn’t be more happy with it.
Sent from my iPhone using svtperformance.com
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The motor spun to 7,200 RPM today. More than I was expecting, made Peak power around the same 6,200ish and kept it there until 7,200.
Congrats sir - that is one fantastic looking and sounding machine!
Excellent results!
That’s awesome!
Sent from my iPhone using svtperformance.com
Sent from my iPhone using svtperformance.com
Sounds killer. A show car with balls!
-J
-J
Sounds and looks amazing!!! Wow
Congrats man!!! That is awesome and great numbers.
I put mine on the rollers this weekend too and came out with 430/430. Like yours I lost a lot of HP and held my tq numbers high.
Those are really solid numbers too! Your attention to detail on your build is second to none. I love it!
Your adjusted numbers would actually be 585/647. You divide by .85 to get the correct numbers. Car looks and sounds great!
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