Horsepower vs fuelflow...
#16
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Originally Posted by B951S
23 degrees at 20psi, is that with race gas?? That's a hell of an advance for 20psi. Must be that big *** intercooler your running. I am running from 18 up to 26 at 20psi using water / meth. Is yours mapped at 23 degrees all the way through the 800 row though or do you build from a lower timing value at mid range to 23 degrees at red line??
Also, how do you like your link 2? Are you using closed loop knock?
THanks!
Also, how do you like your link 2? Are you using closed loop knock?
THanks!
Yes my IC is big, 20x12x3,5". I have never yet had more than 10 degrees C higher inlet temp than the suroundair. The IC seems to work fine.
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No I havn´t yet used knock controll but I can se in my logg that i never had moore than 80 at 6700 rpm and 20 psi.
I like my Link 2, there is things that could be better. For example I would prefer that the inlet temp was measured at the intake so the IC efficiency counts. I would also like to be able to save the "Dataplotting" for later looks. Also the closed loop Lambda control feels a bit slow to be usefull.
But I´m learning every day so in the end I think I will be satisfied. I think it is fantastic to be able to map a car yourself and be close or have better driveability than stock.
#17
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Fuel flow is different than fuel pressure.
You can run 72lbs/hr injectors and keep stock fuel pressure (thus getting the 400whp)
Increase the fuel pressure to 3 bar on those #72 injectors, you should be gaining more hp naturally, but other tuning is needed.
I also heard that the max you should be running is 90% duty cycle on any injector on our cars, so its a delicate balance of flow vrs pressure...........
#55 injectors are good enough for 350whp, anything more would require bigger injectors (using decent fuel pressure)
Heck, you can set a 3bar fuel pressure on those stock injectors, but they would be maxed out.......getting leaner and leaner throughout the rev wave, not enough flow.
Am i right here or did i say something that screwed things up again
You can run 72lbs/hr injectors and keep stock fuel pressure (thus getting the 400whp)
Increase the fuel pressure to 3 bar on those #72 injectors, you should be gaining more hp naturally, but other tuning is needed.
I also heard that the max you should be running is 90% duty cycle on any injector on our cars, so its a delicate balance of flow vrs pressure...........
#55 injectors are good enough for 350whp, anything more would require bigger injectors (using decent fuel pressure)
Heck, you can set a 3bar fuel pressure on those stock injectors, but they would be maxed out.......getting leaner and leaner throughout the rev wave, not enough flow.
Am i right here or did i say something that screwed things up again
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
#18
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Duke, the “quick and dirty” numbers I threw in there should absolutely not be taken as “the gospel”, but as a bit of a counter to the other ++400whp claims.
Believing in a low ball estimate will also make the eventual dyno run a more pleasant experience (not having to chase unrealistic numbers).
I certainly look forward to seeing a dyno chart on Corleone’s car.
Laust
PS There are good simulation tools on the market (such as Engine Analyzer Pro ), but it does take a few engineering hours and more information than provided here to arrive at believable numbers, hence my “quick and dirty” path.
PPS Horses that stays in the engine after years of (ab?)use are even more valuable.
Believing in a low ball estimate will also make the eventual dyno run a more pleasant experience (not having to chase unrealistic numbers).
I certainly look forward to seeing a dyno chart on Corleone’s car.
Laust
PS There are good simulation tools on the market (such as Engine Analyzer Pro ), but it does take a few engineering hours and more information than provided here to arrive at believable numbers, hence my “quick and dirty” path.
PPS Horses that stays in the engine after years of (ab?)use are even more valuable.
#19
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Originally Posted by Corleone
At the 800 row my ignition start at 18 degrees and from 4500 rpm to rev limit it is 23 degrees. No race gas. Here in Sweden we have 98 oktan fuel, I think I read before that our 98 is like yours 93.
Yes my IC is big, 20x12x3,5". I have never yet had more than 10 degrees C higher inlet temp than the suroundair. The IC seems to work fine.
No I havn´t yet used knock controll but I can se in my logg that i never had moore than 80 at 6700 rpm and 20 psi.
I like my Link 2, there is things that could be better. For example I would prefer that the inlet temp was measured at the intake so the IC efficiency counts. I would also like to be able to save the "Dataplotting" for later looks. Also the closed loop Lambda control feels a bit slow to be usefull.
But I´m learning every day so in the end I think I will be satisfied. I think it is fantastic to be able to map a car yourself and be close or have better driveability than stock.
Yes my IC is big, 20x12x3,5". I have never yet had more than 10 degrees C higher inlet temp than the suroundair. The IC seems to work fine.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
No I havn´t yet used knock controll but I can se in my logg that i never had moore than 80 at 6700 rpm and 20 psi.
I like my Link 2, there is things that could be better. For example I would prefer that the inlet temp was measured at the intake so the IC efficiency counts. I would also like to be able to save the "Dataplotting" for later looks. Also the closed loop Lambda control feels a bit slow to be usefull.
But I´m learning every day so in the end I think I will be satisfied. I think it is fantastic to be able to map a car yourself and be close or have better driveability than stock.
Regards.
#20
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Originally Posted by B951S
My 800 row timing was basically identical to yours for 18psi on pump gas. I gues your bigger IC means you can push the same timing at 20psi. Suggest you log the engine noise, graph it and then set the knock values. Its one of the links strong points. It will pull timing very well when it needs to. Agree on the closed loop lamda, it seems very slow, I've stopped using it as it used ceate horrible fuel maps if I saved a closed loop run. Last question; what static timing are you using?
Regards.
Regards.
Yes, I´m going to use knock control soon. It can be a good safety tool if something goes wrong like fuelpressure failure or similar.
#22
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Originally Posted by hosrom_951
Man, i sure hope to see a pic of your car with a big a$$ front bumper for that intercooler ![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
Originally Posted by B951S
My 800 row timing was basically identical to yours for 18psi on pump gas. I gues your bigger IC means you can push the same timing at 20psi. Suggest you log the engine noise, graph it and then set the knock values. Its one of the links strong points. It will pull timing very well when it needs to. Agree on the closed loop lamda, it seems very slow, I've stopped using it as it used ceate horrible fuel maps if I saved a closed loop run. Last question; what static timing are you using?
Regards.
Regards.