Roots Blower Choices in Acohol Funny Cars

We bought one of the 'Superman' Kobelco units that had the K8's because we were told it was "the blower" and we wanted to try it. It was awesome until the rotor decided to try and break apart after only 30 runs since BRAND NEW. Cost us about 9-10K Canadian to get it on the car and now it's a paperweight. We are now running the Littlefield unit again and really like it. We ran 6.13 @ 233 with it in Seattle on our TAFC that has an old '96 Daytona fiberglass body and is 150lbs overweight, not quite too close on the tuneup yet either. Only shiftin' at about 8900 rpm too.

 

Where 100 pounds over Nathan and shift at 9000. new PSI roots $8910 service kit $1875.

 

Mike,

That is right where our rotor cracked. We are lucky though that we found it before we ran it again. We were just running through the valve lash and noticed a tight spot. So we took the belt off and yep, it was in the blower, but not big deal right? We thought that perhaps one of the screws that hold onto the teflon came out and scarred it up and we'd just have to file it and all better, but then pieces fell out when we took the cover off... We pretty much nailed it down to the big lightening hole is drilled too big making it too thin in that area, but Kobelco disagrees. I believe the same thing happened to Sickles in Edmonton this year when his blower exploded.

I'm not sure what rotors are in our Littlefield - are there any markings on them that you'd be able to tell by????

M Tigges,

Sure would be nice to be able to afford one of them new PSI's, but one expensive blower in 2 years is already over budget for us. That's USD I assume? The performance coming out of them sure seems to be awesome, but you ran big numbers with the Littlefield didn't you? Plus, my grandpa George Sitko lives right around Mert's shop I think.

 

Nathan:

Hearing about the roots problems makes me glad I have a screw. I actually had to clean the outside of the case once this year because it started to get dirty.

Seriously, we went through the roots blower of the week stuff 10-12 years ago and it nearly drove me nuts. Restripping every other run, etc., etc. Now the supercharger is the last thing we worry about.

I have over 100 runs on the PSI I have now and the boost numbers are the same on the last run as they were on the very first run. Don't get me wrong, we keep a good eye on it. And so far that's all we've done. I save the restripping for the paint on my patio deck.

RG

 

That is funny Randy...LOL

 

the problem with the rotors splitting was fixed quite some time ago and any that were found were replaced, Littlefields come with kob k11's or our own, depending on customers wishes, both are so close, I dont even have to change tool location when cutting them. As for Mr. Goodwins comment about restripping his blower all the time, when did he last own one, things have changed since then, not only have rotor profiles changed but we have came up with some case mods also that are making quite big improvements, as for Sitkos comment on having the K9's and then they werent the best, sometimes when your looking for improvments with a product you see things that could be improved after being ran on actual racecars, if we didnt keep making changes, there would still be cast rotor 8-71's on all drag cars.

 

How many cyl heads of the week did randy goodwin go through in the last few yrs?

 

We never had any k9's split, this problem was with the first kobelco's that came out a few yrs back, Mert and Darren figured out what was happening and rectified the problem, any littlefield out there, has a serial # on the top and we can look it up and tell what rotors are in it, and dont worry about to many k9's in littlefield cases, when we figured out they were not working that well, we stopped building all that were on order, until the problem was figured out, Kobelco was on the right track with the k9's but it wasnt quite correct, they have gotten it right with the k11's, and ,yes, k11's can be put in a case that had k9's but not k8's. and earlier when I said there were some case mods, they can be done to existing cases also.

 

i noticed andy you commented on restripping, i run a alcohol dragster with a littlefield 1671 on a 451ci hemi its an older blower with littlefield rotors i replace the whites evry 3 runs and the blacks every 6, i spin it at 50 over if i were to buy a new littlefield with k11 rotors would i be needing to do this more or less often, also with the kobelco rotors i was told they were designed more so to suite the pro mod cars were less overdrive is allowed and therfore you cant spin them really hard as they cause to much heat? im about to upgrade blower and i would like to stick with a rootes as i have experience with them and with our rules here in australia i think i can be competitive if i have a killer rootes blower, we have an over drive limit of 70 percent with a rootes and on my 451ci hemi with a psi i can only spin it at 80 percent, any help much appreciated
thanks aaron

 

To clarify, our blower has the K-8 rotors, and we did only have thirty some runs on it before it tried coming apart on us. We are now out of a blower because the new rotors won't fit in our case, and because I am not willing to pay $5800 to fix a blower I bought new for $6200. I regret ever going away from Mert's blowers, he has excellent service and stands behind his product, so our next roots blower will be one of his.

 

Well its not true what they told you! and the later rotor designs dont have to be stripped constantly. our Mert will go 10 or 12 runs before it falls off. it has k-8 rotors..im sure the new k-11s are just as good or better!

 

Mark, how much does the boost fall off over those 10 to 12 runs?

 

We dont have a PSI high helix Mike

Mert k-8 max boost over finish is 52 @9200 above 1800 corrected 49 that would be a good average with our motor and computer sensors. We dont have manifold temp Mike.