LLLosingit

iTrader: (4)

I wonder what cylinder and exhaust temps top fuel engines run considering the amount of unburnt fuel the passes thru the exhaust. I do know they run extremely rich to keep the engine from burning pistons.

Nitroused383

iTrader: (10)

They actually had twin turbo top fuel dragsters back in the 80's. I read an article in some turbo book that Gale Banks used to mess around with twin turbo nitro v8's. The problem was back in the 80's turbo technology was limited to whatever came on the big diesels. Back pressure was insane and I remember seeing pictures of blocks being split in half. Also check out this to see some in action http://www.dragzine.com/news/what-mi...uel-dragsters/

The 2nd video is actually my home track, pretty crazy to see the stands full of people. My dad and brother work on a top fuel dragster from time to time so next time I go to an event I'm going to see if I can dig up some info from the old school top fuel guys.

gtfoxy

Do tell...

I can see a rotary being much better suited to the fuel.

Right.

That means there is an energy conversion issue.

It needs a motor that has the ability to rpm higher, but it's not about rpm, per say, it is about matching energy exchange rates. The RPM the energy conversion is best is actully the byproduct.

The better the energy conversion, within the system, the lower the EGT's will be.

kingtal0n

iTrader: (1)

My favorite turbo system
http://www.nsxprime.com/forum/showth...=1#post1859077


This is how you do it. out of the way, coated, oilless.

patrick335d

Diesel super stock.
504Ci 6 cylinder.
ported but stock head casting.
2 parallel 4.6" turbos-> 1 4.8" turbo -> 1 5" about 300PSI boost.
redline at about 7K rpm.

diesel consumption about 2.5 gal in 300ft.
water consumption about 3-4 gal in 300ft.
exhaust gas temps about 1600F.

I know some teams tried turbos on hemi V8s and they all called it a day and returned to superchargers.

Nitroused383

iTrader: (10)

Top fuel burns around 14 gallons in a pass but use about 17 gallons including staging and the burnout. The fuel pump is 85 gpm but some of the top guys are running 96-120 gpm now. The guy my dad pit crews for has older alan johnson setup which is probably 8000hp and the nhra guys are over 10,000 hp now.

speedtigger

iTrader: (16)

Mark Oswald from Don Schumacher Racing says that they see 1600 degrees or so in a top fuel exhaust pipe.

The Alchemist

iTrader: (19)

Interesting... good info. So it's pretty comparable to other combustion engine exhaust temps.

So will we ever see turbos in top fuel?

sbcgenII

iTrader: (1)

As soon as the rules change.

oscs

iTrader: (19)

What are the rules? I always though S/C were ran because it was the best option.

gsteele

I think roots positive displacement super chargers only. Exhaust gas driven super chargers not allowed.

oscs

iTrader: (19)

Hmmm any idea why that is?

sbcgenII

iTrader: (1)

Per NHRA rule book
Restricted to Roots-type supercharger, rotor helix angle not to exceed that of standard 71-series GM-type rotor. Turbocharger and/or centrifugal supercharger prohibited. Maximum size: 14-71, 22 5/16- inch case length, 11 1/4-inch case width, 19-inch rotor length; maximum rotor diameter: 5.840 inches including fixed stripping. The top opening may not exceed 11.750 inches in length or 4.600 inches in width. The case must be one piece with removable front and rear bearing end plates; rotor must be contained within one-piece case. Inlet/outlet cavity restricted to maximum 1 inch, measuring from face

sbcgenII

iTrader: (1)

Safety and clean up I'm guessing. Wish they just had a class with unlimited engine rules and just a minimum weight. That would be interesting.

oscs

iTrader: (19)

Agreed. I wonder if Turbo chargers would in fact be faster if given the opportunity.

The Alchemist

iTrader: (19)

I think the problem with that is the human factor. As it is, they are pulling so much G-forces, that some drivers say they black out for a split second. Right now, tire technology is a limiting factor as well, because look at how they have to slip the clutch and I was told by a top fuel driver that they don't actually have it go 1:1 till the 1/8 mile, sometimes later depending on track surface and traction. Too much clutch and it just causes tire shake and a smoke show.

oscs

iTrader: (19)

"Blacking out" from the exceleration... I want to see what that's like so bad

The Alchemist

iTrader: (19)

I remember watching an interview with John Force where he described it and how it took some time to get used to it, and how to prepare for it, like a fighter pilot does. He was commenting on how it caused his vision to blur and the he said that there were times that the tire shake was so violent, it would cause a concussion.

oscs

iTrader: (19)

Man that is just insane isn't it. They should put them on oxygen and in a "bubble" like a fighter jet. Make the capsules mandatory and uniform so everyone incurs the added weight.

The Alchemist

iTrader: (19)

I can only imagine that type of thrust and acceleration.