What boost level do Champ Cars run?

[08Elf]

http://www.cartracingupdate.com/News04/310...generalcart.htm

Reading this above article it says that they can run boost levels from 41.5 - 44 inches of mercury...

Could someone please help me out to do the conversion in PSI or Bar please?

I mean if this is using the same measurement as whats on the standard guages in skylines then they would be running upward of 6 BAR or 84 PSI.....

Is this correct?

If so that awsome.......

[NZM.031]

inches of mercury and psi are almost the same.

if i remember correctly, champ cars run around 44psi.

cheers

Linton

[sewid]

The stock Skyline boost guage in an R33 reads in mmHg (millimetres of mercury)

[Mik]

inches of mercury and psi are almost the same.

if i remember correctly, champ cars run around 44psi.

cheers

Linton

Nah...they definately don't run that much boost. 44 inches mercury is just under 1.5 bar. But I think they are refeting to absolute not relative pressure, so it is about 0.5 bar or about 7 PSI, which is about what I always thought.

[maccattack]

This is taken from one of the CHAMP car sites-

· Nominal power: 750 bhp at 1054mm Hg (Maximum intake pressure on road circuits. When on ovals maximum is 990mm Hg)

· Maximum power: 800 bhp at 1130mm Hg. This amount of power is only unleashed when push to pass is activated. This system was developed in 2004 at request of Champ Car aimed to increace overtaking. This is a procedure where each driver has the opportunity to increase engine power by 50bhp, for a maximum of 60 seconds per race. A steering wheel-mounted button activates the system and a combination of increased turbo boost and fuelling provides the extra power, to allow drivers to mount a passing move or fend off competitors.

1 mm Hg (or millimetre of Mercury) is equivalent to .001316 atmospheres.

This would then equate to a maximum boost of 1.487 bar or 21.57psi or 43.91 inches of mercury

[Mik]

This is taken from one of the CHAMP car sites-

· Nominal power: 750 bhp at 1054mm Hg (Maximum intake pressure on road circuits. When on ovals maximum is 990mm Hg)  

· Maximum power: 800 bhp at 1130mm Hg. This amount of power is only unleashed when push to pass is activated. This system was developed in 2004 at request of Champ Car aimed to increace overtaking. This is a procedure where each driver has the opportunity to increase engine power by 50bhp, for a maximum of 60 seconds per race. A steering wheel-mounted button activates the system and a combination of increased turbo boost and fuelling provides the extra power, to allow drivers to mount a passing move or fend off competitors.  

1 mm Hg (or millimetre of Mercury) is equivalent to .001316 atmospheres.

This would then equate to a maximum boost of 1.487 bar or 21.57psi or 43.91 inches of mercury

Yes, but I am quite sure that that is absolute, not relative pressure. You need to subtract 1 bar from those figures.

[maccattack]

Just came across this - different again

"Over the past few years, as speeds rose, CART reduced the amount of boost from a whopping 45 psi down to 34, using pop-off valves. The valves are electronically monitored by sensors. The only way for teams to get power up was by increasing rpms, which was costly. "Part of the cost savings this year was our ability to reduce the rpms back to 12,000. But to bring the power back up again, we increased the boost," says Bisco. Currently, 41.5 psi blasts through the turbocharger, making 750 hp at 12,000 rpm. "

[pinoi_boi_r33]

Yes, but I am quite sure that that is absolute, not relative pressure. You need to subtract 1 bar from those figures.

i very much doubt that its not absolute. Pretty much all car related stuff is in relative. Even if you did subract 101.325 kPa from it (1 atmosphere not one bar even tho they are close) it would run under .5 bar!!! thats stock skyline territory.

[nmcmahon83]

yea... I'm pretty sure its up around 40psi, as most of the evidence seems to suggest. I remember Neil Crompton saying this at this years indy.

[TTT]

he didn't say 40psi... he said 40 inches of mercury absolute.. which is equal to about 1.2 bar which is about 19psi.

that is what champ cars run... except when the overtake button is pressed as described above..

[INASNT]

Yep they will run 40+psi all day as they are specially designed turbos made with exotic materials like titanium shaft and wheels.

I seen a champ car engine up close which was on display at local autobarn a few months ago. The turbo looks the size of a garrett GT40 but would cost 10 x as much

[TTT]

did you not read the post above yours?

[INASNT]

Yes, but they can run at 40psi if they wanted because of the turbo design.

A few years ago they would have been running this type of boost, but like f1 cars they have tried to slow them down.

[nmcmahon83]

.

[TTT]

If he said 40mmHg, then that means they are running 80psi.

Unless I am very much mistaken, the standard skyline boost guage is in mmHg, and 3.5mmHg=7psi...

So i'm not sure where you're figures are coming from saying that 40mmHg = 1.2 bar

40 "inches"

"INCHES of mercury"

not mm

INCH

[Roy]

LOL...dont know what turbos they run today, but it was only a few years ago that they ran plain bearing turbos from Allied Signal and Holset. Hell in '96 (or around then) Ilmor / Mercedes ran a pushrod engine as the rules allowed them to run more boost.

It would not surprise me if these turbos were still used as there arent many BB turbos the size that they run. If you want massive boost on race engines look at some of the Pikes Peak cars, and some of the older Le Mans cars...occasionally they got up around the 2.0bar

http://www.skylinesaustralia.com/forums/sh...&highlight=Indy

[slow13dude]

Can anyone explain how the "on-demand" turbo boost works then?

Coz on our cars boost is driven by RPM.

[INASNT]

antilag system?

[dangerous_daveo]

Can anyone explain how the "on-demand" turbo boost works then?

Coz on our cars boost is driven by RPM.

Like the 'scramble' button on some ECBs I would have thought.

And just pointing out if anyone doenst know, they are running a control cosworth engine these days which as far as I know have a larger capacity than the older pre control engines. Sooo at a guess as they are a control engine they would have to be more reliable, there for more capacity, a bit less boost... So once again at a guess I would say (for a race car) they are running a fairly conservative tune.

[INASNT]

Roy

Talking about indy cars i found the perfect track car for you so you wont have to make excuses when the r32 ends up sitting in the pits instead of on the track

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...4506215714&rd=1

Only 10hrs left, hurry