The “Redneck Blower”, fact or fiction?

[michael_loomis]

Thanks for the well thought out post JD!

If there is a diaphragm as claimed, all that would be for naught. I don't see where the diaphragm would be though, unless the tires are tubed and the wheels have secondary stems.

I'm certain he lost way more than 10% would have given him at high altitude, where as the TDI engines suffered nearly nothing. Could be a potential gain going up dunes however. He did win with 15 mins to spare without it connected, although his only time getting stuck was with it disconnected too.

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[Suhaib Kiani]

JD, Nice to meet you! Good to know that I am not the only alien lurker around here

I do accept the point (made on the forum) that "air after the restrictor is air after the restrictor" and something not to be taken lightly in FIA events. So that leaves Robby pretty exposed whenever they found it....

Nevertheless, I just can't get my head around how a 3hp compressor with a bottle can provide 20% / 10% or even 5% boost to an engine easily producing excess of 400HP (post restrictor). We're talking at least 20 to 80 HPs incremental power here which if possible should make a good case for taking off turbos and superchargers and going for 10HP compressors and large air tanks! Or am i missing something here.....

[J.D..]

Thanks for the well thought out post JD!

If there is a diaphragm as claimed, all that would be for naught. I don't see where the diaphragm would be though, unless the tires are tubed and the wheels have secondary stems.

I'm certain he lost way more than 10% would have given him at high altitude, where as the TDI engines suffered nearly nothing. Could be a potential gain going up dunes however. He did win with 15 mins to spare without it connected, although his only time getting stuck was with it disconnected too.

If by "diaphragm" you mean the "manifold"(pneumatic control unit seems to be the official name for that part) well of course there is one, one might consider it the heart of a ctis system. Also there is no need for secondary stems(they are not even allowed per FIA rules), the tube just goes on the normal stem and opens the stemvalve, the pressure is then controlled by the pneumatic control unit.

Like i said, this would not be a "double your power all of the time" kind of system. In the case of a 10% boost at 10% of the time this would only be an 1% gain on average. So not a huge gain, but not negligable also. And if used in that way it would without a doubt be illegal. And believe me or not, i've seen bigger names do weirder stuff for much smaller gains.

[Wendell #527]

JD that is good insight. I was thinking he'd have to be deflating his tires to add hp, but I get it now. I didn't realize they had a bottle of compressed air to pull from. Still, for them to allow it and then DQ after he started winning is really weak. Changing their minds would be ok, just tell him to unhook it. To change their minds AND DQ him for it is 'tarded. It did add a lot of drama though, and probably boosted interest in the US. To see Robby smoke em after he was pissed was pretty epic.

[J.D..]

JD that is good insight. I was thinking he'd have to be deflating his tires to add hp, but I get it now. I didn't realize they had a bottle of compressed air to pull from. Still, for them to allow it and then DQ after he started winning is really weak. Changing their minds would be ok, just tell him to unhook it. To change their minds AND DQ him for it is 'tarded. It did add a lot of drama though, and probably boosted interest in the US. To see Robby smoke em after he was pissed was pretty epic.

Well, passing FIA scruiteneering doesn' mean that the car is legal, is just means that they didn't find anything obvious. Also, the biggest part of scruiteneering is about the safety features, the technical legality part is mostly taken on face value. In the very high end racing series like WRC the technical controls are much more in detail, in WRC they even have surprise "car weighting" in between stages, the have a custom built scale on a trailer for it. And guess what, in the french WRC round of last year FIA dqed a semi-works Citroen(in third place when dqed) for coming up short 4 kg on one of those surprise "weightings". Yes, a french car, in a french rally dqed by FIA. "Merde" happens, even if your french:-)

[Ramsey_ElWardani]

JD that is good insight. I was thinking he'd have to be deflating his tires to add hp, but I get it now. I didn't realize they had a bottle of compressed air to pull from.

There was no bottle of compressed air. The spare tires act as the air reservoir and an electric pump keeps them inflated, no where near the pressures a bottle can handle.

If you look at available pictures, you can see the CTIS hoses, and that the connect to the tires' (sp? lol) valve stems, which have valves in them. We have all deflated a tire by depressing the valve stem valve - do you really think there is enough air flow through a valve stem, even if the spares were inflated to 110 psi, to super charge a V8 that is already pumping lots of air?

Good write-up J.D. but something is missing - and few know what it is.

[J.D..]

There was no bottle of compressed air. The spare tires act as the air reservoir and an electric pump keeps them inflated, no where near the pressures a bottle can handle.

If you look at available pictures, you can see the CTIS hoses, and that the connect to the tires' (sp? lol) valve stems, which have valves in them. We have all deflated a tire by depressing the valve stem valve - do you really think there is enough air flow through a valve stem, even if the spares were inflated to 110 psi, to super charge a V8 that is already pumping lots of air?

Good write-up J.D. but something is missing - and few know what it is.

Dear Ramsey,

Why would one rely only on the spares as reservoir when the rules allow for a 15l bottle? This would mean that after two punctures you would be left without reservoir. And just because you don't see the bottle on some pictures doesn't mean it isn't there, that bottle can be placed anywhere in the car for weight distribution reassons. And yes i know that i'm only guessing, but that could be easily fixed by comming clear and publishing the installed ctis in detail. FIA won't do this right now because of the pending appeal.

Best regards,

J.D.

[pappawheely]

Any additional air would have to be matched with additional fuel right? Wouldn't that detract from your effective range?

[J.D..]

Any additional air would have to be matched with additional fuel right? Wouldn't that detract from your effective range?

True, but as i said, we're talking about an on average 1%, maybe 2, gain, so an extra gallon per 100gallon. I think the Hummer can manage that sort of extra weight.

[arqangel67]

J.D. you bring up some intersting ideas and calculations but as Ramsey has stated there is no compressed bottle of air. If there was than he would not be having these issue's with the aso. All we know is that Robby was using the spare tires as a resevoir. He had means by compressor to refill tires but not to deflate them. A vaccum pump would have created more parasitic drag on the engine and would have been another item that could've potentially failed, so my guess is that he chose to use engine vaccum (if approved which it was) to deflate the tires faster. Your calculations are pretty good but that is only for 1 liter of fuel his engine is 7 liters which would require alot more air than even a 15lbs. and tires combined could supply.