Interesting EG33 output comparison...

[Sonar]

...And for those interested people....

Mean Effective Pressure (bar or kPa)
– power per unit displacement and stroke
– e.g. mep = Pn*1000/(VN)

• mep in kPa
• P in kW
• n=1 for 2 stroke, n=2 for 4 stroke
• V = engine displacement in Liters
• N = engine speed in rps

...or read the lots here


/Sonny

Originally posted by Chiketkd


Another observation is that the hp and tq values are almost identical on the SVX

-Chike

Apparently Subaru likes making engines with similar torque / HP ratings. Seems like quite a few Subarus have engines like that.


Dave

[Chiketkd]

Originally posted by mbtoloczko
MEP is found from:

BHP/(rpm*displ)

rpm is in krpm (rpm/1000)
displ is in liters

MEP is a better way to compare the efficiency of different motors because it takes into account the rpms the motor is turning at peak HP. Its important to take rpm into consideration because greater rpm is an easy to create more power (assuming that some amount of torque can be produced).

Here are the results
car-------------disp (cc)----bhp----rpm at peak HP----MEP
300zx----------2960-------222----6400--------------11.72
Supra----------2997-------220-----6000-------------12.23
3000GT SL---2972--------222-----6000-------------12.45
SVX------------3317-------230-----5400--------------12.84

When taking into acct rpm, the SVX motor takes the win in efficiency.

It would be interesting to see what the SVX motor would crank out with longer duration cams, higher lift, and appropriately tuned intake and exhaust. If the MEP of 12.84 could be maintained but peak HP moved to 6500 rpm, the motor would be cranking out 275 HP.

Nice!

That's a very impressive MEP for the EG33. 275hp definitely seems like an attainable figure if those changes were made to the engine... DAMN!

-Chike

[Chiketkd]

Originally posted by red95svx
Apparently Subaru likes making engines with similar torque / HP ratings. Seems like quite a few Subarus have engines like that.

Very true Dave. Doesn't the EJ22 make like 135hp and almost that exact figure in torque? Also the USDM STI makes 300hp and 300lb-ft.

-Chike

[Chiketkd]

Originally posted by Sonar
...or read the lots here

Very good read Sonny. Started reading through the document, but need to bookmark it for later...

-Chike

Originally posted by Chiketkd

Very true Dave. Doesn't the EJ22 make like 135hp and almost that exact figure in torque? Also the USDM STI makes 300hp and 300lb-ft.

-Chike

Yep and the 2.5 L is about 165 hp and similar torque, and even the 2.0 turbo has hp and torque ratings that are close.



Dave

[Sonar]

It seems to be more correct to use the BMEP in our findings because

... the MEP not BMEP includes more than the average pressure on top of the piston during the power stroke. It's an average involving the measurement of cylinder pressure on all four of the strokes, and anything done to change the pressure in one or more of the strokes will affect the MEP with an increase or a decrease depending on what is done.

The BMEP is a hypothetical MEP determined by using known brake horsepower or brake torque.

taken from here

..and even more here


makes sense.....or... ...yeeh...whatever....



/Sonny

[benebob]

Originally posted by THAWA


you realize that an auto is not slower than a manual right?

The REAL Legacy turbo (i.e. 91-94) posted faster auto times than manual times. I'm sure the crappy Mazda wanna be they sell now doesn't as it has more turbo lag than a turbo prop plane .

[SVXRide]

After reading all the posts in this thread I suddenly realized that I haven't been trying to make my car faster, I've really been trying to make it more efficient!
-Bill (dyno on the 15th.....dyno on the 15th!!!)

[drivemusicnow]

Originally posted by Chiketkd

Here's the deal - an auto trans is almost identical to a manual except for the torque converter! <snip>

-Chike

^is not true... autos and manuals are completley different, go onto www.howstuffworks.com for a halfway decent explanation of each.

For better/more fun explanation... go to a junkyard, buy one of each, and tear them apart and try to rebuild them

[oab_au]

Yes that was a pretty vague description of how a torque converter works. The missing component is the Torus or Stator. This is the bit that produces the torque multiplication.

I'll write something on them soon.

Harvey.

[thundering02]

Originally posted by drivemusicnow



^is not true... autos and manuals are completley different, go onto www.howstuffworks.com for a halfway decent explanation of each.

For better/more fun explanation... go to a junkyard, buy one of each, and tear them apart and try to rebuild them

[SVXelerator]

SVXRide,
Where are you going to dyno your car? Who's going to have the higher HP - you or Mr. Chike?

[benebob]

Originally posted by SVXelerator
SVXRide,
Where are you going to dyno your car? Who's going to have the higher HP - you or Mr. Chike?

Here's my bet!

SVXride will have a lower hp but a better curve and higher torque
Chike will have the number.

Do I have any takers? Why must you do such fun things after my SVX is put away for the winter???

[Chiketkd]

Originally posted by benebob
Here's my bet!

SVXride will have a lower hp but a better curve and higher torque
Chike will have the number.

Do I have any takers? Why must you do such fun things after my SVX is put away for the winter???

Thanks for the vote of confidence!

Personally though, I think Bill will have higher hp and torque numbers as he now has the ECUTune Stage 1 installed in his car. That chip is the main difference between his stock '92 and my stock '96 (my 4.11 gears won't affect my dyno numbers as gearing is factored in).

-Chike

P.S. My prediction is that Bill makes a hair over 170hp and a similar number in torque, while I'll be somewhere in the mid 160's...