RedBull
Registered
All stock motor with stock mufflers ~ been 9.81 @ 141 MPH in Sacramento *
Closer to sea level ~ the better she runs *
Post Your 1/4 Times And Mods.
- Thread starter Jake whitebird
- Start date
All stock motor with stock mufflers ~ been 9.81 @ 141 MPH in Sacramento *
Closer to sea level ~ the better she runs *
ItsDooomz
Registered
OK, I'll give it a shot. Our engines burn an air/fuel mixture. The more air (oxygen) you can get into a cylinder, the more power you can potentially make. Turbos can force in more air = more power. The air we breath is roughly 20.9% oxygen by weight. Nitrous Oxide (N20) is 33% oxygen. More oxygen means you can burn more fuel = more power. Still with me? OK, when your intake valve opens the piston doesn't suck air into the cylinder, atmospheric pressure forces air into the engine. At sea level, gravity's effect on our atmosphere exhibits 14.7 lbs per square inch of pressure. The higher you are, less air is pushing down so that number gets smaller. Gravity also has its effects. The further away you are from the center of mass, the less force it applies. On an accurate scale, you would weigh less at Jake's house that you would at mine.
Elevation is simple. It's a distance relative to sea level. My home in Florida is 11 feet above sea level, Jake lives 5300 feet above sea level. Bad Water basen in Death Valley California is 280 feet below sea level.
Density altitude by definition is air density given as a height above mean sea level. Several things effect air density. Temperature, barometric pressure/altitude and humidity. Cool air is denser than hot air so cool air is heavier = lower DA. Higher barometer = lower DA. Humidity doesn't effect the numbers as much as tempature and pressure but it needs to be included. High humidity = higher DA. In summary, air = power potential. Lower DA = higher power.
How much does DA effect performance in drag racing ? A bunch! Super Comp races on an 8.90 second index everywhere... Except Jake's home track Bandimere Speedway where the ridiculous elevation slows the index class down to a 9.50. And six tenths is a bunch...
ali123
Banned
if we are dealing with forced induction... is the effect as great as that as on a naturally aspirated motor? 14.7 lbs per square inch of pressure AT sea level... this number seems very important... do we have a way of working with this number to figure out losses? D/A... elevation/ temp/ barometric pressure..... all affect THAT NUMBER 14.7..... or did I miss something....
That is the point of why we use DA. Lower DA=better performance. A DA of 0 means you are at standard temperature, pressure, and water. A DA of 5000 means you are at the equivalent of 5000 feet of elevation at standard temperature and water. DA tries to roll up the variables and make one comparable number out of all of them. Bottom line, you can forget the 14.7 and just use DA if you like. I find that water is the worst way to lose DA. I prefer the heat instead of the water so DA isn't perfect.
Jeremy Godo
Registered
You can get away with riding a stroker motor on the street as long as the compression is not way high. I was thinking of doing a 1507 stroker street strip wih 13.1,
i was gonna call bob and ask him his thoughts but you already have proved its good to go.
Joshua Dumas
Registered
11.177 @ 153.67.....
04LE
Registered
Well your traps good!
Joshua Dumas
Registered
.287 reaction, this was my best of 5 last year on the turbo setup with probably 5 practice street launches. I kept spinning on the track, probably because I never did any burnout to warm up the tire
Here is a pic of my old mate from NT Australia , he's been running his L0 Gen 2 stock motor , short wheelbase and slammer equipped lowered with CT Brocks pipe , power commander . He has been running down to regular 9.4's at close to 150mph . I haven't a pic of any slip , but it is the quickest streetbike up top there as I write . He is over 60 , and is light as and can still ride pretty hard . He has always been a naturally gifted rider , as anyone who knows him can attest , and is a brother from another mother .
Getting out there and actually riding your bike down the quarter usually ain't as easy as one might think ... so well done , keep going and listen to any good advice on pointers to cut your ET .
As Six said , you got to start somewhere and you are now over that crest !!
Mr Brown
Registered
Nothing wrong with that at all. It will get better. You'll drop times pretty quick, then get to a point where gains are slow to come. Keep after it. Remember we are talking about fractionss of seconds here.
Yeah, that's slow but back when I raced my street/strip cars I never went 119 mph n/a. I remember when I was in college seeing GS1100's go 120 mph and was absolutely amazed as I was running around 100 in my mildly modified daily driver which was pretty good at the time. As you go back you will see seconds drop off very quickly, then the paced of improvement slows. Work on getting the throttle OPEN as quickly as you can.
moko
Registered
What are the mods?
Mathewrussell52
Registered
Better question is what’s left to mod.
Full on Pro Street built motor running turbo (build thread in the turbo section if you look up my name). Just a little stage 1 RCC turbo kit. Utilizing ECU editor for tuning.
Things left to do this upcoming winter after race season is a full sized pro street turbo kit, new fuel management system (going fuel tech), and do the front end as I am currently running factory offset, factory front wheel, and factory height shocks.
So still a bit to do. Cool thing is with this is that I built and tuned everything myself. Only thing I didn't build is the RCC Turbo kit, which was definitely worth the money!
I did run better after this time slip, I did a 7.82s at 180mph. However, I think there is a 7.7 in it, hopefully a low 7.7. lol
