Thanks Todd.

Here's something that people ask every once in a while.
Q: What is our Volumetric Efficiency?
A: Look at the charts.

Ok, on with the simulations. Here's Todd's request - the 10 vs 12 vs 14. Yeah, it is an interesting comparison.

Crane #10
Intake lift : .354 in.
Exhaust lift : .354 in.
Intake centerline : 105 ATDC
Intake duration : 242 degrees
Exhaust centerline : 111 BTDC
Exhaust duration : 242 degrees
IVO : 16 BTDC
IVC : 46 ABDC
EVO : 52 BBDC
EVC : 10 ATDC
notes : definately whoop up on the stockers

Crane #12 - see above

Crane #14
Intake lift : .364 in.
Exhaust lift : .345 in.
Intake centerline : 105 ATDC
Intake duration : 246 degrees
Exhaust centerline : 111 BTDC
Exhaust duration : 238 degrees
IVO : 18 BTDC
IVC : 48 ABDC
EVO : 50 BBDC
EVC : 8 ATDC
notes : The turbo grind. The split duration only allows 26 degree total overlap - defeating reversion. Better than stock N/A - and isn't that what you are when you're not boosing anyway? If you look closely at it, it's just a street intake with a better-than-stock exhaust.




Here's another chart for the drag racers. This one has Crane's draggers, and I'm also including the Gude Bullfrog regrinds on this.

Are the Gudes draggers? Well, they have a drag lift, but very little duration - because they're regrinds. They have nearly identical lift to Crane #16 drag cams, but less overlap than the #10s. Thats the big performance difference between new billits and proper regrinds - you can't safely attain the same amount of duration on a regrind that you can with a new bumpstick. If you try, your srpings and rockers will take a beating...but if you keep the ramp angles safe then you can get descent lift. I think it's interesting that the Bullfrogs have less overlap than Crane's turbo grind, so for a turbo application they should keep reversion at bay pretty well - but they have really good lift. I'll personally find out how well they do under boost sometime this spring.

Crane #16
Intake lift : .374 in.
Exhaust lift : .374 in.
Intake centerline : 104 ATDC
Intake duration : 250 degrees
Exhaust centerline : 112 BTDC
Exhaust duration : 250 degrees
IVO : 21 BTDC
IVC : 49 ABDC
EVO : 57 BBDC
EVC : 13 ATDC
notes : First stage draggers. 208/208@.050 gives a whoppin 13 degree overlap @.050! Now we're talkin.

Crane #18
Intake lift : .394 in.
Exhaust lift : .394 in.
Intake centerline : 106 ATDC
Intake duration : 258 degrees
Exhaust centerline : 114 BTDC
Exhaust duration : 258 degrees
IVO : 23 BTDC
IVC : 55 ABDC
EVO : 63 BBDC
EVC : 15 ATDC
notes : All out draggers. 216/216@.050. Look at that lift! Look at that duration! There's no way that you can't hear that these are installed. These things tip the scale with 98% Volumetric Efficiency at 5500 RPM. The VE is over 90% from 4000 on up - and remember these sims are all run on a stock setup(low intake CFM, manifolds, CR and all). These cams will actually top 100% VE with 11:1 CR.

Gude Bullfrogs
Intake lift : .376 in.
Exhaust lift : .376 in.
Intake centerline : 109.2 ATDC
Intake duration : 237 degrees
Exhaust centerline : 107.4 BTDC
Exhaust duration : 237 degrees
IVO : 9.3 BTDC
IVC : 47.7 ABDC
EVO : 45.9 BBDC
EVC : 11.1 ATDC
notes : Regind. Beutiful lift. Only 20.4 degree total overlap should defeat reversion for turbo applications. Looks like a dragger from the lift...but it performs like a basic street cam.




95 Eclipse RS : 5 speed
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html