I love this post.

HMMM.. 29 ten second passes in a row... Lowest E.T.'s I ever ran.

Yeah..We turned that bitch up and I thought it was pretty good.

This is from a guy who owns a KB and has ZERO plans on getting a 2.3 Whipple.

Thats some 20 hp. LOL

VINNIE

 

Why have a 2.3 whipple when you can have a 3.3 whipple

 

What upper plenum have you been running on your KB? C&L or JL style? THat could be where your 20hp is.

Also what does everyone not understand about both blowers being on the same pulley ratio might not be the same combo but the end ratio is the same. Then they are stated to both be making 15lbs. SO this means they are both making the same HP for the same lb of boost. Now it could be a dif result when the pulley ratio is turned up on both of them. Now on the whipple side of the fact to make the KB equal you have to buy a JL plenum which makes the cost of the KB 2-400 more than a whipple.

 

I'm also amazed. I guess that them thar cifers are a' stumpin' some.



But also consider that all that has been discussed is shaft RPMs. Both the Whipple and KB have gear drives to the rotors, so the rotor RPMs may be different.



Anyone know the gear ratios for the two?

 

What are you trying to get at Vinnie? Your input is valued here, too!

 

Also, I don't know if anyone caught this, but I mentioned that the Whipple rotor teeth(# of blades on each rotor) are 3 and 5 and the KB are 4 and 6. Can anyone provide anymore insight on this. You would think more teeth, more air.

 

By this picture It looks like one rotor "the 5 tooth" will spin at the "shaft" rpm, the mating rotor must spin faster. 5 teeth to 3 so the "3 tooth" rotor must spin 1.66 times to equal one revolution of the 5.

On the KB a 6 to 4 setup the "4" must spin 1.5 times to equal one revolution of the 6 shaft.

Take that how you want it. At this point in time I think they wash. Unless the KB does have gear reduction. But that would require more than 2 gears

 

I realize after doing the math that the pulley ratios are pretty much the same, but there is another factor with the different sizes. A 10 lb lower with a 3.5" upper, is going to have much less slip than a 4lb lower with a 3" upper. I use to have lots of slip issues when I ran the Whipple years ago. The 3" upper did slip, with a 6lb lower, and forget about the 2.75 and 2.5 uppers I had. Those needed to be grooved to fix that (before anyone was doing "no slip" pulleys) and even then they still slipped.

Also, the dyno was done on two different days. There was no mention of barometer readings. That is the single most important weather condition for making power on a forced induction vehicle. If the BP was 29.2 on one day, and 30.7 on another day, that can be a 10-20hp difference.

I'm not trying to split hairs or anything here, but for a true back to back test, you have to get rid of as many variables as possible. I think the testing done on this particular truck is a good test. After all, it's not easy to do "perfect" testing on the customer level. However, the people on this forum will pick apart any test to the molecular level, and those who are "pro this" and "pro that" will never be satisfied.

 

I agree with you 100 percent Sal!

 

NCSVT--- are you running a stock block/rods,.etc...... I was told after 450 hp the rods cant handle it-- L's have bad rods.. I wanted to go with the big KB and they told me that I should prob concentrate on getting the bottom end built or buying a jlp shortblock first becuase the rods will be the first thing to go.....

 

Fully built motor. Yes the rods are usually the first to go on a stock block. If anything, yes get the motor built. You can put a KB on a stock block, you just have to make sure you have it tuned right, and all the necessary things to go along with it like a Mafia or SCT BA2400 mass air meter upgrade, injectors, fuel pumps, possibly longtubes, etc... Any of the vendors will be happy to assist you with your goals.

 

So, where are the dyno numbers for the KB and Whipple at 21psi?

-a

 

Waiting till next week. I am having other things done to my truck, too.

 

when you guys were compairing blower rpms and rations, you said a kb with a 10 lower and a whipple with an 8. This test on the whipple was done with a 4............where did the 8 come from.

No one can come to conclusions untill this thing is out there for a while. The KB's have been proven, although they've had a few problems.

The real comparison is the boost levels, which both maxed out at 15psi.

 

The math is based on lower pulley inches, not pounds of boost.