Turbos at Bonneville

[don pennington]

It's no secret that turbos make big horsepower. But I have noticed in the last few years that records set with turbo powered cars are putting the records out of reach of anything except turbo powered cars, "out of reach" is being kind, they are on the moon.

Over the last few years John Raines and his V6 turbo Buicks have eliminated competition is several classes, most recently the 214 record in E/BGC (which he set with the Lund Cadillac) then erset at 240 plus then ran 261 the following day, qualifying for another hit in the same class. When you look at the A through D supercharged gas coupe records, they too are turbo records with no contenders to date. 

Effectively what these cars have done is eliminate anything except turbo power. Is that a good thing?

For the guys that have put performance to such a significant level....good for them! They have found something that works are are reaping the benefits.  But is it a good thing?

If it was a performance part or high performance brain that gave a performance advantage, well that is what Bonneville and racing in general is all about....it is the rainbow we are all chasing. But when it eliminates competition for the foreseeable future, is that a good thing?

It would be easy to say "well just get a turbo" (as many have done), but that in itself undermines the vary reason guys work all year and go to Bonneville and El Mirage. Can we see a future where all supercharged classes are turbo only classes?

So is this performance disparity seen as the natural evolution of speed or is it an undermining factor?

[JackD]

It is the same reality as the people that hate for anybody to run gas in a fuel class and set records that are a long time standing.
"It is not how you make power but more how you apply it." (me)

[desotoman]

Don,
 
You are 100% correct about the performance of the turbo cars. IMO they would not be able to do what they are achieving without the help of computers and or engine management systems. Also by using turbos the aero package can be kept to a minimum which equals less drag.

To answer your question I will go out on a limb and say as long as electronics are allowed in all classes, there is no end in sight. Eventually the driver will just sit in the car or on the bike and go along for the ride. The computers will take care of everything. The cat is aready out of the bag, and there is no getting it back in.

To my knowledge there is only one class where you cannot run and aftermarket engine management system and that is the Classic Category. Turbos are also not allowed on Vintage class engines competing in Vintage Body Classes.



Tom G.

[Dean Los Angeles]

A supercharger (also known as a blower) is an air compressor used to force more air (and hence more oxygen) into the combustion chamber(s) of an internal combustion engine than can be achieved at ambient atmospheric pressure (natural aspiration).

That's straight from Wikipedia.

Naturally aspirated engines are limited by how much air you can suck into the engine.

Blown engines are only limited by the strength of materials in the piston, rod, crank, etc. If the turbocharger was the ultimate answer, then perhaps you can tell me why all the Top Fuel classes use a roots type blower?

Every blown record that was set with a turbo could have been done, and can be beaten by, a supercharger. The package size of the turbo lends itself to fitting in smaller spaces. Or maybe you should be using the setup on the diesel truck where twin turbos blow into a roots supercharger?

"When it eliminates competition" Isn't that every LSR racers goal? It sure is mine. I want to be able to have my great grand kids be able to see my record still in the books. (Note: I'm only 38 mph short of getting the record, and only need, oh say 40 on top of that to put it out of reach. Yep, that's doable!)

[desotoman]

If the turbocharger was the ultimate answer, then perhaps you can tell me why all the Top Fuel classes use a roots type blower?

Every blown record that was set with a turbo could have been done, and can be beaten by, a supercharger.

Dean,

I have to disagree with you on this one. All Top Fuel dragsters have to run a roots blower. It is mandated by NHRA who does not want the T/F dragsters to go any faster. They spell out the exact dimensions on the blowers. A T/F motor with a turbo and engine management system would easily make 1000 more HP than the roots blower they are forced to use. It takes in excess of 800-1000 hp just to turn the roots blower.

A turbo hardly takes any HP to turn, compared to a Roots type supercharger. So by using a turbo you actually gain the HP required to turn the blower and put it at the flywheel, where it can be used.

Tom G.

[russ jensen]

Or maybe you should be using the setup on the diesel truck where twin turbos blow into a roots supercharger?

I do believe the roots is required to get air into the 2 smoke to get it started-think in years past some tried to use big turbo only & start w compressed air- don't think that worked very well- trouble w/ Detroit's is the root is way to small for the cubes it sits on & expect to get any pressure- so they added a big whistle to pump the old 318 to 350 for example.{from  our experience a 8-71 is about right for a 327}

[russ jensen]

It's no secret that turbos make big horsepower. 




So is this performance disparity seen as the natural evolution of speed or is it an undermining factor?

It sure ruins the sound of a piston eng-which I consider the best part-might as well go to local airport & listen to jets.

[bvillercr]

At the drags, the only supercharger that can challenge a roots blower on fuel is the PSI and it got out-lawed.   I don't believe the turbo can produce the instant boost to launch off the starting line like the roots.

At Bonneville the roots is at a disadvantage in that it usually sticks out of the hood of a car or in the air on a roadster and some lakesters.  It is deffinately a disadvantage on gas.  If you look at the same engine size and class and compare the both, unblown cars are not much difference in speed.  You put an inter-cooler into the mix and it gets better.

turbos are great applications for Bonneville there is no doubt.  But I personally don't like the sound of a blown motor with turbos.  The efficiency of the turbo is near 75%, a roots is about 45%.  That is a big difference in heat production.  Advantage turbo, unless you add fuel which will cool the heat and run much better for a roots.

Diesel is an up and coming phenomenon which I really don't have much to say or know about, except that the charge put off on diesel is greater than most.

Our application is a centrifugal supercharger.  It's advantage is that it is under the hood, it is also about 75% efficient and we only need one (we used to run two).  It is very comparable to the turbo  except the sound is to my liking.  You add an inter-cooler and it gets even better.  Look at the pro five-o racers and the turbo and centrifugal cars are very close.  

[don pennington]

I guess my point of view is from the preservation of the original hot rod influence at Bonneville. If these kinds of systems continue unchecked, and without any place for the "traditional" racer to go, Bonneville will certainly become a robot driver community. It's a tough management responsibility SCTA has, balancing...or trying to balance these various interests.

NHRA had to choose....speed that would ultimately cost their insurance companies financially....class management which would cost them TV exposure because the shows ran too long....and/or internal management of the racers.

Years ago they chose....which cut deeply into the origins of drag racing, the average guy racing his daily driver. The chose because the money was on TV, which cultivated commercial interests in sponsoring the events and race cars.

With the onus being on SCTA to protect the originals of hot rodding, aren't they obligated to manage in a manner that does that?

[bvillercr]

Every racer at Bonneville is a hot rodder.  It might not be your type of hot rodding but it is someones.  Just remember this the roots blower isn't always the best, but it sure sounds like it is.  BTW the roots blower was developed 30 years after the centrifugal.  Hot rodding was a little behind in the good ol USA at that time.

[Dynoroom]

Let me start with this, I go to Bonneville to see…

1 Fast cars
2 Different types of cars
3 Hard core Hot Rodding

Turbos make some cars fast but I can point to many roots blown cars too.

1 The Burkland family, fastest piston engine streamliner
2 Fast Freddy Danenfeltzer, currently the fastest lakester
3 Jim Howe’s AA/FMR first 300 mph roadster
4 Lindsley & Leggit fuel altered @ 308 mph, fastest in the class

I can go on but the point is the roots blowers can hold their own so lets not start making more classes by splitting roots vs turbos. Besides if we start that argument we’ll need to split the type of cams guy’s use (flat vs roller tappet), or the types of heads as my turbo engine is still using 23 degree heads (vs 18 degree vs SB2.2 vs splayed valve) .

As far as Tom G’s point on electronics goes I disagree. It’s made it easier maybe (you don’t get to see the issues we run into before a good performance) but we can and have been successful with turbos using carbs (both draw thru & blow thru, still have the D/BGMS record with a draw thru system) Hilborn type fuel injection, as well as EFI. 

Lastly, Bonneville is tough. It looks deceptively simple from the outside but requires many different types of disciplines to be successful, from abstract ideas to the procurement of hardware to financial management with a determination to your commitment. Yesterday 8-13-07 the MacDonald & Pitts Firebird (#135) used a gasoline burning big block Chevy with a squirt of N2O ran 300 mph to become the first normally aspirated door slammer to run 3 bills. No turbos and lots of the above.

[Dynoroom]

A turbo hardly takes any HP to turn, compared to a Roots type supercharger. So by using a turbo you actually gain the HP required to turn the blower and put it at the flywheel, where it can be used.

Tom G.
[/quote]

Your leaving out the fact that a turbos has signiacant back pressure to work that a belt driven blower does not. I think we could call this HP lost.

[JackD]

It is a common belief that Turbos operate on HRMS (Hot Rod Magic Stuff), I'm glad.

[dieselgeek]

A turbo hardly takes any HP to turn, compared to a Roots type supercharger. So by using a turbo you actually gain the HP required to turn the blower and put it at the flywheel, where it can be used.

Tom G.

Your leaving out the fact that a turbos has signiacant back pressure to work that a belt driven blower does not. I think we could call this HP lost.
[/quote]


Darn, he beat me to it...   reality is, the turbo takes almost as much power in backressure as the equivalent supercharger takes to turn...

advantage of the turbo is, it's easier to cool the air charge after the turbo when compared to a roots blower.   We're running a 14-71 on a BBC out here, and the high end water cooler that sits under the blower seems to cool the intake charge only a fraction of what a typical air-water or air-air intercooler on a turbo engine can do.


I like turbos, and I really don't like it when people claim an unfair advantage.   Also, I believe there is NO WAY you could do an EFI system with a turbocharger, and run as quick as a top fuel dragster.  Think about how many injectors you'd need to run the quantity of fuel those engines consume...  plus, turbos don't lend themselves to quick throttle response or pedalling very well.  You can get them to spool during staging, b ut once you're off the throttle during a 4-second pass, all bets (and power) are off.  Turbos aren't the greatest thing in the world, just another way to build big power.

-scott

[desotoman]

A turbo hardly takes any HP to turn, compared to a Roots type supercharger. So by using a turbo you actually gain the HP required to turn the blower and put it at the flywheel, where it can be used.

Tom G.

Your leaving out the fact that a turbos has signiacant back pressure to work that a belt driven blower does not. I think we could call this HP lost.
[/quote]


Hi Mike,

I never said a turbo's boost was free, what I said is that compared to a roots blower it takes less HP to operate, which equals more HP at the flywheel. I am talking about a standard Roots Blower vs. a turbo. For the fun of it lets take Bvillercr numbers on efficency. Turbo 75% efficent vs. Roots Blower 45% efficent. Just those percentages alone give a big plus to the turbo. When you can reduce the amount of HP it takes to create a givin amount of boost you will see the numbers show up in HP gain, or at the flywheel.

I hope this clears up any misunderstanding.

Tom G.