i agree with panther. One complaint I have with whipple is they just dont offer much tech info on their products. At least not on their website or online.

I do think the 8.3L should be reserved for big power stuff. I am just speculating here, but whipple's max rpm reccomendation for the 8.3L is 11,000. Lets say you bolt it on a 540ci and want to run 7psi. The blower is likely driven around 1:1 ratio. So, at 4,000 rpm cruise, you're at 4,000 rpm blower speed. same at 6,000 engine rpm.

Now, looking at the more common smaller whipples, such as the 2.3, 3.3 etc, and you bolt that on the same 540, making 7psi. Its max rpm is 16,000. You'd likely be driving it close to its max rating.

I think the 8.3 is a poor choice for a low boost setup. It probably offers little advantage in terms of power to a comparable roots at the lower boost ranges. Roots blowers do pretty well at low boost levels like 5-7psi. They dont consume a ton of power or make a bunch of heat there. However, they fall off as boost increases. Even on whipples website regarding the 8.3, it shows a 120hp gain over the roots at 7psi. Yet, a 200hp gain at 12psi. at 20psi of boost, its probably 300hp gain. The big whipple is probably best reserved for 1200hp plus applications. Not what you'd want at the 900hp level. Probably much better off with a 3.3 or 4.0 for something like that.

Im working on a friends pair of 612ci engines with 8.3L whipples. Theres alot of things I dont like about the combo. First, is the stroke. Its a 4.75 stroke in a 10.2 block. I dont care for the rod angle, or the piston setup. I'd have went with a 4.25 or 4.375 stroke. I'd also have ran the static compression around 7.5 or so, instead of it being closer to 8.5. Reason being, I'd feel better about utilizing the supercharger to make the power. Turn the blower faster, which would probably put it in a better effiency range. I just dont think this big blower likes being spun at low rpm.

This engine had a 240/248 .612 lift crane cam in it. at 14% over, it made 10-11psi with the original builder. That cam was killing this thing, with a 4.75 stroke. Going substantially bigger on the camshaft, Im sure if we kept the 14% overdrive, it would drop a few lbs of boost. Then plan to spin the blower harder to get back there. Hopefully it likes that. We will see.

that cams smaller than the 525 efi cam, better suited for a 502 with a 3.3 whip

you talking about the 240,248 cam?its not smaller duration wise,525efi cam is 236,244

I was referring more to lift .610/.632........both similar, anyway as MT stated to small for that engine

Whipple has been proven for many many years and ask some of the big name engine builders what there making reliable /BIG power and its whipple ... Bob Teague has no problems making a 1400 Hp pump gas engine with a 1 year warranty . and thats just 1 Example

Yea that prob aint happening with a roots blower. Not on pump gas thats for sure!

Whipple pump gas 91 California Octane

Next dyno I`ll see the fuel distribution on the dyno with 10 02s

When did a 9.0L 548ci become "small cubic inches"?
One day I`ll grow up and get myself a real engine with some cubic inches I guess.

... when you can punch out a race Dart M block (tall deck) all the way out to 731 CID / 12 L (with the raised cam for clearance)