Kenne Bell efficiency

GT Doug · 10-02-2008, 12:38 AM

Hi, I am starting to get interested in supercharging my GT. I am curious to hear you opinions on the efficiency of the 2.6 KB vs the M122H. I have been told that in some instances the KB can be too powerfull, and when tuned down, can generate too much heat.
I understand there are 2 types of KB a S model for under 15 pounds and an H model for 15 plus. Which model do you use? Would the S model be better suited to applications under say 400rwKWs?

Thanks Doug

XRQTOR · 10-02-2008, 01:24 PM

The S & H models of the KB blowers are auctually the same blower they just run a different base plate, the H series has a smaller opening.

GT Doug · 10-02-2008, 03:48 PM

Quote:

Originally Posted by XRQTOR

The S & H models of the KB blowers are auctually the same blower they just run a different base plate, the H series has a smaller opening.

Yes, but from what I have read, I believe they compress the air differently, for effeciency in different boost levels............

DarkXr · 10-02-2008, 03:59 PM

Go for a twin screw blower like the KB or whipple. The roots type blowers are not efficient, check the respective websites out and note the volumetric efficiency spec of each blower. After research not really a fan of the KB units nor the way have been setup in the past (Leaving alt in original position).

XRQTOR · 10-02-2008, 05:07 PM

Quote:

Originally Posted by GT Doug

Yes, but from what I have read, I believe they compress the air differently, for effeciency in different boost levels............

Correct mate, i dont want to butt in here to much but Chris or Paul will answer all your questions.

AGRO · 11-02-2008, 02:19 AM

Quote:

Originally Posted by GT Doug

Hi, I am starting to get interested in supercharging my GT. I am curious to hear you opinions on the efficiency of the 2.6 KB vs the M122H. I have been told that in some instances the KB can be too powerfull, and when tuned down, can generate too much heat.
I understand there are 2 types of KB a S model for under 15 pounds and an H model for 15 plus. Which model do you use? Would the S model be better suited to applications under say 400rwKWs?

Thanks Doug

Hello Doug.
Firstly, a Kenne Bell when 'tuned down' does not create too much heat!
Discharge temps will ALWAYS be much lower then that of a Roots compressor, when used in the same configuration.
For a roots blower like the M122, they have to spin at a faster rpm than that of an equivalent size twin screw, to produce the same boost. The faster a supercharger spins, the more heat it will produce.
Efficiency is ALWAYS better (because of the design) with a twin screw than that of a Roots. Don't get me wrong here, there is still nothing wrong with a roots blower. They work! There are just much better options out there in the way of twin screw compressors.
Comparing the KB 2.6 to the Eaton M122? Well, there is no comparison. The 2.6 will win hands down in any area, be it with discharge temps, efficiency, higher boost aplications, less hp from engine to operate, etc, etc. But, you have to remember, the KB 2.6 is a larger displacement supercharger than that of the M122, so naturally it should be superior.
On our kits, the KB 2.6 is only working around 65% of it's ability, and that's at 6000 engine rpm. At 4000rpm, it's working around 50%. There is plenty of room to move in other words!
Yes, KB have the 'S' and the 'H' series superchargers. We use the 'S' series as our boost levels are below 10psi. The S & H series are almost identicle. They have the same internal rotors, and same size housing. The only difference is the exit port on the bottom of the supercharger. The 'H' series port is smaller, giving more time for the compression to take place. In high boost applications, this results in a cooler discharge temp, than that of the 'S' series at that same high boost level. The 'S' series is fine for 400rwkw, no problem.
Hope this helps with your queries.

Regards

AGRO.

GT Doug · 11-02-2008, 05:54 PM

Thankyou for your reply Agro, and yes, that answers all my questions, and some. The KB really does sound like an impressive blower.

Just out of curiosity, what is the most power you are making with the S model 2.6 at 15psi?

Thanks Doug.

DarkXr · 11-02-2008, 07:02 PM

AGRO, what boost levels could you achieve with the H series 2.8L blower and how would the crank bearings etc go with the increase in inertia?

Aussie MustangGT · 11-02-2008, 10:07 PM

Quote:

Originally Posted by DarkXr

Go for a twin screw blower like the KB or whipple. The roots type blowers are not efficient, check the respective websites out and note the volumetric efficiency spec of each blower. After research not really a fan of the KB units nor the way have been setup in the past (Leaving alt in original position).

Do I understand you correctly when you said you are not a fan of leaving the alternator in the original position? I think Paul's setup of leaving the alt. in the original position is absolutely brilliant from an engineering point of view when it comes to using one belt to drive all components, with everything in perfect alignment and no chance of throwing the belt, unlike another kit on the market that is having more than it's fare share of problems in this regard. Other than the incredible torque generated by the KB setup down low, it hardly makes any whine with its helical cut gears which is something that pleases me no end. It makes a little bit just as it first loads up but then seems to be much quieter. An absolutely brilliant kit (with intercooler) and the best thing I have ever done to my "Henry". Congratulations Paul and Chris.
Cheers,
Ian.

AGRO · 12-02-2008, 01:03 AM

Quote:

Originally Posted by GT Doug

Thankyou for your reply Agro, and yes, that answers all my questions, and some. The KB really does sound like an impressive blower.

Just out of curiosity, what is the most power you are making with the S model 2.6 at 15psi?

Thanks Doug.

Doug.
A 'S' series KB 2.6 on our intercooled kits make around these power outputs.
10psi 360-400rwkw.
12psi 450ish rwkw.
All on pump gas, but results will vary from car to car.
We see have seen very high 400's rwkw with race fuel on 12psi.
Now, before you say that's for me, remember this.
These results are from our own test cars (stock internals), including Chris's race car.
We have obtained some big numbers from our own engines, but know at any time, they could let go.
We much prefer to 'tone down' a customers car.
We aim anywhere between 350-400rwkw for a customer, depending on individual car setup prior to the kit being fitted.
A supercharger is only an air pump, and that's all.
The limiting factor we have is the engine and drive train, NOT THE KIT!

15psi?????
Well, follow the trend above, and take a stab in the dark at the engine work needed to prep a motor for that output, because I can guarantee you will need it.

Hope this helps Doug.

Regards

AGRO.

AGRO · 12-02-2008, 01:40 AM

Quote:

Originally Posted by DarkXr

AGRO, what boost levels could you achieve with the H series 2.8L blower and how would the crank bearings etc go with the increase in inertia?

Hi DarkXr.
The 'S' and 'H' series blowers produce the same boost at a given rpm.
The 'H' series is just better suited for higher boost applications, say 15psi+.
Using a 2.8 over a 2.6?
Well, if a KB 2.6 kit has a 2.3:1 ratio belt setup, using the KB 2.8 in it's place might use around a 2:1 ratio. You don't need to spin the 2.8 as hard, as it is a larger displacement pump per revolution. Saying this though, we are no where near maxing out the KB 2.6 at this stage. So, at a quick calculation, a KB2.8 will be somewhere around 30psi at 6000 engine rpm.

Hope this helps.

Regards

AGRO.

DarkXr · 12-02-2008, 10:22 AM

Thanks Agro, whats your opinion on driver intertia with the BP system and high boost, what about belt slip?

AGRO · 12-02-2008, 06:58 PM

Quote:

Originally Posted by DarkXr

Thanks Agro, whats your opinion on driver intertia with the BP system and high boost, what about belt slip?

Driver Intertia??????

As for belt slip, we have had NO problem what so ever.
We also have NO problems with belts being thrown. All accessories stay in original position, so this eliminates any possibility for relocated accessories to be out of aglinment.

Regards

AGRO.

DarkXr · 12-02-2008, 11:01 PM

Quote:

Originally Posted by The Old Hoon

Do I understand you correctly when you said you are not a fan of leaving the alternator in the original position? I think Paul's setup of leaving the alt. in the original position is absolutely brilliant from an engineering point of view when it comes to using one belt to drive all components, with everything in perfect alignment and no chance of throwing the belt, unlike another kit on the market that is having more than it's fare share of problems in this regard. Other than the incredible torque generated by the KB setup down low, it hardly makes any whine with its helical cut gears which is something that pleases me no end. It makes a little bit just as it first loads up but then seems to be much quieter. An absolutely brilliant kit (with intercooler) and the best thing I have ever done to my "Henry". Congratulations Paul and Chris.
Cheers,
Ian.

I agree that in terms of engineering that this kit is great, and I have conveyed this opinion to Chris on a number of occasions, however in high boost applications, the blower will create a higher drive inertia on the crank pulley opening up the possibility of bearing damage etc. I believe this is why BPT moved the alterantor.

If the alternator could stay in its original position and allow the blower to run 20psi plus then I would have no drama, but if this level of boost caused damage to the FEADS then I would it be concerened, sorry to hijack your thread however it seems I going through a similar choice at the moment as you are. Hope Chris or Agro can help, by the way Agro when I wroe 'driver interia' i menat DRIVE INTERITA, which refers to "drag" and "pressure" applied to the accessorie drive. Cheers.

DarkXr · 12-02-2008, 11:03 PM

sorry for spelling mistakes. its late.

**Bluepower** · 13-02-2008, 08:31 AM

DarkXR,

we have been really blessed with our setup - up to 14psi we have not yet seen an issue with it to the point where the base kit needs any change to the drive setup.

Having had the first Positive displacement blower kit running on a Boss motor is Australia, we have done extensive R and D to the point where we see the market trending towards the 350rwkw to 500rwkw.

Our kit is one of the few that by cleverness in design, will cater for this power range with all OEM components on the stock drive.

Most people that have been in other PD blown cars are literally stupefied by the torque our setup produces. There is not a turbo or competitors product in the country that turns slicks at half track like the KB does.

My car with 480rwkw is not driveable. Period. and it has seen 8000 rpm through the factory drive setup without problems.

Hope this helps, good luck with your setup, hope it suits your requirements.

Chris

Aussie MustangGT · 13-02-2008, 09:46 AM

Quote:

Originally Posted by Bluepower

DarkXR,

we have been really blessed with our setup - up to 14psi we have not yet seen an issue with it to the point where the base kit needs any change to the drive setup.

Having had the first Positive displacement blower kit running on a Boss motor is Australia, we have done extensive R and D to the point where we see the market trending towards the 350rwkw to 500rwkw.

Our kit is one of the few that by cleverness in design, will cater for this power range with all OEM components on the stock drive.

Most people that have been in other PD blown cars are literally stupefied by the torque our setup produces. There is not a turbo or competitors product in the country that turns slicks at half track like the KB does.

My car with 480rwkw is not driveable. Period. and it has seen 8000 rpm through the factory drive setup without problems.

Hope this helps, good luck with your setup, hope it suits your requirements.

Chris

When I said in my post above..... "I think Paul's setup of leaving the alt. in the original position is absolutely brilliant"....... I meant.... "Chris and Pauls setup..........."
I shouldn't post so late at night.
Cheers,
Ian.

**Bluepower** · 13-02-2008, 01:53 PM

Ian, the engineering behind the kit is all Paul. I see some real genius in his work, I cannot lose when I have one of the best fabricator/engineer's on my team.

superpursuit83 · 13-02-2008, 04:38 PM

You mean the sparky that does all the work, while you entertain the clients, don't you Chris?

:

Aussie MustangGT · 13-02-2008, 06:20 PM

Quote:

Originally Posted by Bluepower

Ian, the engineering behind the kit is all Paul. I see some real genius in his work, I cannot lose when I have one of the best fabricator/engineer's on my team.

I must admit, having spoken to Paul numerous times, that the genius tag is well founded.
But even more important at this stage, I want to know when the genius tuner is coming up to see me.
I know... I know..... when he gets some time. All I can say is patience Ian..........patience!!
Impatient Ian.

Jason50 · 14-02-2008, 02:49 PM

Quote:

Originally Posted by AGRO

Driver Intertia??????

As for belt slip, we have had NO problem what so ever.
We also have NO problems with belts being thrown. All accessories stay in original position, so this eliminates any possibility for relocated accessories to be out of aglinment.

Regards

AGRO.

12,000Ks now on mine since the fit up and no issues with the belt or drive at all. I just take this kits quality for granted now as I just about only raise the bulge when mates want to have a look :evil3:

superpursuit83 · 14-02-2008, 03:08 PM

Mmmm, I ran the super small pulley for 5,500km's and did not get any slip either. (only 8psi with my underdrives)

DarkXr · 14-02-2008, 03:12 PM

Quote:

Originally Posted by Jason50

12,000Ks now on mine since the fit up and no issues with the belt or drive at all. I just take this kits quality for granted now as I just about only raise the bulge when mates want to have a look :evil3:

Thats good, I have no doubt the kit is quality, but what about at high boost, I dont think anyone is running this kit at high boost as yet. could be wrong.

GT Doug · 14-02-2008, 06:40 PM

I must admit, this concerns me also, somewhat. From all the pictures I have seen, all the US supercharged modular motors run 2 belts.

Please though, someone correct me if I'm wrong.

XRQTOR · 14-02-2008, 07:12 PM

Quote:

Originally Posted by GT Doug

I must admit, this concerns me also, somewhat. From all the pictures I have seen, all the US supercharged modular motors run 2 belts.

Please though, someone correct me if I'm wrong.

Running an addional pulley which bolts to the crank would be more of a concern to me as it then puts the stress further from the first bearing, increasing the leverage on the crank. I don't think anyone has put as many k's or 1/4 mile runs on their kit as Chris & Paul have on their OWN cars during testing.

DarkXr · 14-02-2008, 07:21 PM

Does BPT's kit use two belts?

Whitey-AMG · 14-02-2008, 07:33 PM

So we're saying here that its possible to get 350+RWKW reliably with ALL STOCK INTERNALS on the BOSS 290???????????

How does the ZF 6A cope ??

I'd be interested in a KB set up down the track on the GT as well...........just concerned about fit quality , longevity of drivetrain components etc........

Pardon my ignorance here as well, but I thought all S/C applications ran a low Compression ratio. The 290 runs around 10.5 : 1. Is this modified for the fitment ??

Without being too blunt, what is the relative $$$ price range for supply and fit to 290 ??

JOSH · 14-02-2008, 08:46 PM

Quote:

Originally Posted by DarkXr

Thats good, I have no doubt the kit is quality, but what about at high boost, I dont think anyone is running this kit at high boost as yet. could be wrong.

give me a couple of weeks and ill let you know, but with all their testing im sure it will be fine, if their was a problem with the set-up the boys from the states would have said something

JOSH · 14-02-2008, 08:50 PM

Quote:

Originally Posted by ESP

So we're saying here that its possible to get 350+RWKW reliably with ALL STOCK INTERNALS on the BOSS 290???????????

How does the ZF 6A cope ??

I'd be interested in a KB set up down the track on the GT as well...........just concerned about fit quality , longevity of drivetrain components etc........

Pardon my ignorance here as well, but I thought all S/C applications ran a low Compression ratio. The 290 runs around 10.5 : 1. Is this modified for the fitment ??

Without being too blunt, what is the relative $$$ price range for supply and fit to 290 ??

i was running 382rwkw's for around 4 month's without any problems, but that was with a vortech,

Aussie MustangGT · 14-02-2008, 09:34 PM

The problem is that this kit can make more power than you or the transmission can ever handle. As you probably know I totally rebuilt my motor running 9.0:1 compression so that close to standard timing can be used. The problem is always going to be (other than the transmission) the centre bearing and CV on the tailshaft, the front flexible rubber coupling and the CV's on the driveshafts. That is why the Ford utes are better suited because of their solid rear axle and why a solid rear axle is used on the 2007 Ford Shelby Cobra GT500 and independant rear ends on the rest of the Mustangs. We haven't got a hope in hell of the rear end hanging together on an XR8 or GT above probably 350-400 rwkw with the KB. Probably the only solution is universal joints throughout and upgrade of the tailshaft and centre bearing, resulting in a less than smooth drive. I hope somebody proves me wrong. That is why I feel my main tune is probably going to be 300-350 rwkw which is unbelievable with the torque available. I am waiting to see if Harrop Engineering can come up with something, but I am sure whatever that will be will be the limit of what can be done other than the $11500 complete rear end that Chris keeps talking about.
Cheers,
Ian.