bsh

iTrader: (1)

The Dynapack measures hp at the hubs. When looking at the dyno software, you can see the "Torque" graph. If I take logs from my dyno with me home, and view at my Dynapack viewer program that is installed on my personal computer, It shows "Torque flywheel". It does still show the same torque anyway.
At the dyno I can choose between "Torque" and "Torque Flywheel"
I spoke with Dynapack earlier about the ability to select only "Torque" at my personal computer at home, but if I understood correctly, it will come in a newer software update for the Dynapack viewer.

I have seen other manufactors dynographs ie Buschur also shows flywheel power, but as long as the correction factor is 1.00, it actually shows power at the wheels.

Keep up the good work Spyros!

kouzman

iTrader: (6)

Since we are talking 4g63 engines regardless the fuel used (gasoline or alcohol) don't you guys think that John Shepherd's 190+ mph Talon or even Brent Reu's dragcar have insane amounts of power!

If I remember correctly David Buschur builds Shep's motor. Maybe he could chime in...

How much wheel horsepower would someone need to get the Talon to 195 mile traps? And on that number let's add a very conservative 15% loss from drivetrain loss (it's way more probably because of the slicks...imagine dynoing the car on 18s and street tires)....

Dave?

JohnBradley

iTrader: (30)

Those are the 2 cars that I was referring to. They make more power than the map allows because of the rest of the combination. The same reason we have made 522whp on a stock turbo that only moves 42-44lbs per minute. The turbo is part of the equation. Rau runs a 95mm giant at insane boost to run high 6s at 199-201. John runs 7.70s and has been reputed to be in the 1500whp range based on weight and e.t. and is not using as large a turbo as you'd expect.

While you explained the frictional losses well, you still didnt explain why the power doesnt stay linear based on boost. The simple fact is it wont on a given turbo its just not what happens.

I inadvertently posted as Lucas last night and then realised it and logged in as me (darn shared computers anyway) and made the second post. Our 4508 experience was only halted because the driver at the time couldnt make it work. We went back the the 4202 and make enough power to keep the car together and going straight down the track. That particular car was really close to moving an observed 113lbs/min just based on the power it made.

03whitegsr

iTrader: (8)

It would be interesting to see a lab grade mass airflow meter on some of these cars. 500+ on the stock turbo is amazing and it would be cool to see if it's just flowing well past where the map says it can or if you have just upped efficiency that much. From some of the posts I've seen, it seems like you (JohnBradley) have gone to great lengths to reduce frictional losses and increase engine efficiency.

rolly1818

all about getting air in and out of an engine really. its late and my eyes are hurting from trying to read this post

i am gonna subscribe and get back in tomorrow morning, this one seems interesting!

03whitegsr

iTrader: (8)

There is a lot more to making power then only getting air in and out. Most engines are only around 20% efficient on converting chemical energy to mechanical energy. Picking up just a few percent by dropping frictional losses and improving thermal efficiency can pay off in total power.

But I have to wonder, in the case of 500+ on the stock turbo. Is it from engine efficiency improvements or does the turbo just flow that much and JB's motor is only at the typical efficiency levels?

I'm guessing it's from the work they have put into improving efficiency where ever possible, but it's a guess and hard data would be a lot more interesting. When you really look at compressor flow maps, it becomes apparent that there is a lot of "room" off the map and things like air density have a HUGE impact on airflow capability. 500HP on the stock turbo is probably very doable even with a stock efficiency motor, but it would require very dense air to do it.

batty200

iTrader: (3)

Another thing to consider is the fuels used. Methanol and ethanol will make more power per lb of air flow than gasoline. So a methanol car like rau or shep can make a ton of power on a smallish turbo. I think shep was on a 74mm when he went 195mph and I beleive they had limited rau to a 71mm when he was whooping everyone in nopi/nhra and he was still going bottom 7's.

03whitegsr

iTrader: (8)

Yeah, and think that is what Extreme Tuners meant by "chemical efficiency" too. Not sure though as it really doesn't have anything to do with efficiency but actual energy content of the fuel.

I think GM was using a 70mm turbo for a while and breaking 200mph, they cut them back to like 67mm and they were still breaking 200, if I recall correctly. They claimed they were over 1400 HP on the 70mm turbo.

Extreme Tuners

GM ecotech used our 80mm combo although they had midle efficiency 16v engine from 134.8cuin they produced 1400hp at 9000rpms and 900ftlbs at 7100rpms at 55psi. Imagine they had only 30.5mm (1.2'') exhaust valve, and poor flow figures (222cfms at 28 inches) tested. This Hp record from GM achieved by our custom built 80mm "secret" turbo and they had full boost from 6800rpms. Was methanol also. That was before 4-5 years.



I will come back with pictures from our custom parts as i promised.

New world record coming soon with dynoplots !!! Stay tuned


Thanks
Spyros

leecavturbo

ppl need to understand that turbo's are only a part of the equation to making power.
afaik turbo manfacturers only specify max output using a specfic fuel type i.e pump.
so a "200hp" turbo could make 2000 if all other ingredients are right

EvoLutionized8

iTrader: (62)

wow, that pretty much sums it up for me... My only question to Spyros and crew would be you seem very knowledgeable in your field, so why not develope more practical and applicable applications for the masses around the world. What I mean by that is, I'm not driven to obtain the highest HP numbers, I need useable power throughout. I want consistency, reliability and of course, power. I have no affiliation to a certain vendor, I have respect for a product and customer service. If that is not your goal, then I can respect that as well... I'm just curious if you are here to service the community or let us know what big numbers you have...

detroit pistins

iTrader: (102)

Spyros, welcome to evom.
and I must say, I am very impressed with ur knowledge. Glad to see u share it with us.

Migsubishi

iTrader: (38)

Hell yes, +1

03whitegsr

iTrader: (8)

Interesting...
I talked to one of the engine team members and he said it was an off-the-shelf GT4294R...

Are you talking before or after they specifically capped the turbo size on the Ecotech? At that time, they were limited to a (I believe) a 70mm inducer.

I know the first year out, they came out strong running class limit of 80mm and they were untouchable. Then the NHRA came out and said "GM gets a smaller turbo and more weight, but everybody else can stay the same." You know you're fast when a sanctioning body specifically targets you though...

Arkitek

iTrader: (17)

love the car , and power, and looks . But who the heck makes a drag car and says they dont care about the et becuase they just want power on a DRAG car? oh well.....