Alcohol dragsters - I don't get F.I. vs. blown (1 Viewer)

[jim]

Dave Rieff and Bob Frey usually mention the performance differences of fuel injected versus blown alcohol dragsters.
I'm pretty sure the blown cars are fuel injected, not carbed, so I don't get it.

 

[CrewGuy]

F.I.= Nitro
Blown= alcohol

 

[jim]

I sure didn't realize that. Thanks.

 

[T.Smith]

Both cars are fuel injection. The blown car uses a supercharger to ram air into the engine, the A/Fuel car doesn't.

 

[john]

The alky likes to spin, the nitro wants a heavy load on it.

 

[jim]

I'm assuming the alcohol classes are limited to 500 inches like the Top Fuel classes. So, if you put a blower on an "injected" alcohol motor and dropped the CR as needed, you'd have a Top Fuel motor.

 

[sparky]

No 500 inch limit.
Most Alcohol FCs are more than 500", around 526" I think. Dragsters are considerably less that 500", in the 450" range

 

[HEMI6point1]

I'm assuming the alcohol classes are limited to 500 inches like the Top Fuel classes. So, if you put a blower on an "injected" alcohol motor and dropped the CR as needed, you'd have a Top Fuel motor.

Not to mention a huge cost increase.

 

[john]

Not to mention a huge cost increase.

And piles of broken parts.

 

[jim]

I'm sure they are more expensive parts, but an alcohol motor makes lots of horsepower too don't they? I have absolutely no idea, but they always say the fuel cars are 7000 or 8000 HP - depending on who's talking - but I'd think the alcohol cars must make maybe 4000 to 5000 to run 275 MPH. Just a gut feeling, I don't know.

 

[MM]

I'm sure they are more expensive parts, but an alcohol motor makes lots of horsepower too don't they? I have absolutely no idea, but they always say the fuel cars are 7000 or 8000 HP - depending on who's talking - but I'd think the alcohol cars must make maybe 4000 to 5000 to run 275 MPH. Just a gut feeling, I don't know.

best estimate i got was from one of Manzo's guys.....about 3000hp in a BA/FC

 

[none]

T/Ad fuel motors run around 420 to 450 c.i.( with a pounds per c.i. weight), with a clutch like T/F and limited number of discs, no trans and a set rear end ratio. Blown T/AD run a different size motor( with a different pounds per c.i. weight), a clutch set up similar to a "street" clutch and a transmission. Not sure if their rear end ratio is set.
What is unfair, is injected nitro can only run 97% nitro, while blown alcohol cars can run 100% alcohol.
What is great is the competition BETWEEN the two different combinations.
I don't know of anyone involved in T/A that isn't great!
Lee
Nitroclovers

 

[jim]

Too bad the season is over. I'll watch the alcohol classes with renewed interest now that I know the difference between FI and blown.
I'm trying to remember what they always said about which did better when. I'm thinking it was the FI cars did better on hot days.

 

[MM]

Too bad the season is over. I'll watch the alcohol classes with renewed interest now that I know the difference between FI and blown.
I'm trying to remember what they always said about which did better when. I'm thinking it was the FI cars did better on hot days.

other way around.....A/FD loves the cool weather with lots of oxygen and little moisture and hates it when it's hot and humid

blown cars generally have an advantage in the hot weather

 

[Rajunz]

Too bad the season is over. I'll watch the alcohol classes with renewed interest now that I know the difference between FI and blown.
I'm trying to remember what they always said about which did better when. I'm thinking it was the FI cars did better on hot days.

........and you will now notice the difference in their sounds!

A few guys that were running for the Championship built an A/Fuel car for the spring and fall races and a Blown Alky car for the summer months.