I know it is going to sound like a crazy question, but it can be done first -- as in add a few more ponies and while saving the dough for a built bottom end, the user can still enjoy it...

so, here's the question:

On a stock bottom end, let's assume a 4lb lower is what we would call a very safe daily driver. Given that *assumption*, Kenne Bell sells the unit with a 3" upper to make approx 12.5lbs of boost with the stock lower pulley. Would this be considered the same as the eaton with a 4lb lower?

So, if this is the case, it is said the KB can cleanly make 10HP per PSI without dropping off. So, we can then assume 40HP over stock? Stock being around 340RWHP so we're talking 380RWHP?

Is this the case or am I missing something?

Thanks

Ken

 

sounds right to me. is it true the Kenne Bell doesn't whine?

 

Ken and that math......lol....I love it!!!

KB no whine.......I heard JL's truck at Cecil, It seemed to whine pretty good. I do believe that he had the *prototype* on. (I think)

Here's a question.... Is it okay to rebuild the bottom end NOW and save some dough. Just replace the rods? Or is that a waste of money?

 

Once you have the engine apart, you might as well replace everything. What you save in parts cost, you will spend in additional labor.

Piston/rod combos have become more and more reasonable as more vendors offer them.

 

My truck whined louder at idle and cruising with the KB at 15psi. Once you start spinning it faster the lower rpm whine fades some. Open it up though and watch out....sounds like a siren.

 

Your simple question brings up a number of interesting issues. First, pound-for-pound, KB boost will be "safer," as the KB makes less heat at any given boost level.

Which brings us to the second issue--tuning. People claim things like "16 PSI is the limit for a stock bottom end." Yet, how many people are running 16 PSIG without a chip? So virtually every 16+ PSIG engine that has blown has had an additional variable--the chip. It takes a LOT of clean boost to frag an engine. It takes just a little detonation.

At 16 PSIG, at the upper revs, the Eaton is just making heat, not power. That is why the peak power drops off for each extra pound of boost with the Eaton, while the KB, which is still operating within its efficient range at 12+ PSIG, is still providing nearly linear increases.

I am thinking of trying the KB (or perhaps Works) with the stock chip, putting it on a dyno, running up the boost until the A/F gets dangerous, then back it down a notch. With 100 octane fuel, MM&FF got 522 HP at 21 PSIG with the stock chip and fuel system. It remains to be seen if this can be done with crappy 91 CA fuel.

I am extremely conservative when it comes to engine mods, but would not hesitate to run a KB at 12 PSIG, stock chip and all.

 

Ken FYI...

Im lovin that 6# pulley!!

 

I agree with Tim. I'm planning a blower replacement once things settle down a bit and there are a decent number on the street. I think a mild chip (Sal's with knock sensor enabled?) would allow for some tuning and optimization without straying too far from the safer stock parameters. I'd love to be able to run the boost I have now (4lb lower) but without the added heat. I've noticed that after a couple laps the heat soak gets bad enough to notice a substantial performance loss. Maybe a new blower will mitigate that somewhat.
I'm kind of leaning towards the works. I saw a KB on a rousch truck two years ago and was unimpressed with the appearance and sound. Still, I'm reserving judgement until several units of each have been deployed and all the fireworks (figuratively and literally) are over.

 

If you are thinking of running 21 pounds of boost on 91 octane, DON'T DO IT ! You will probably have a haz-mat team out cleaning up the oil. Way too much cylinder pressure for our wonderful 91 octane overpriced crap! Chip or no chip, it is going to detonate at that boost level. If you want to try it, do it on any truck but yours. Ha Ha. The problem with these blowers is that it is way too easy to get greedy. Just change the pulley. Each 1/4 inch smaller is worth about 30 to 40 rwhp. The k/b blower is some of the cheapest hp that you can buy. Over do it, and it can be some of the most expensive hp that you have ever bought. I run 13 lbs on 91 on the street everyday and have had zero problems. It would be fun to turn it up another 30 to 40 hp but I am chicken. I like the way it runs so well that I don't want to break it. Skip

 

Cool... Love that sig... lmao!

Ken

 

Skip... you are running 13lbs on the stock bottom end, right? What is that, a 3" upper and stock lower on the KB? Didn't you say you dynoed at something like 425 RWHP?

Ken

 

couldn't you do it the other way around though? seems to be the final cost of a KB/tune etc. is probably around that of replacing some your internals (rods, pistons,) with forged goodies. you can always enjoy that but just slapping on an 8#er (pretty cheap when you're talking aftermarket blowers and built-motors)...

then just save up for that KB. of course the downside is you're overspinning the blower a lot w/ an 8#...

just an idea...

 

13 lbs is with a stock lower and a 3.25 upper. You are correct on the hp. Skip

 

Hey, Skip...

Have you taken it down the 1/4 yet? I would love to know your before and after times...

Thanks,

Ken

 

No, I have not ran it at the drags. Just too lazy, I guess. Smknjoe ran his with the same mods as mine except a 3" blower pulley and went 12.30s @ almost 112 mph. The k/b blower makes these trucks pull like a freight train clean up to max rpm. Skip