stony Posted January 9, 2002 Share Posted January 9, 2002 Well i found a shipping doc and the wieght of my z is 2850 with all fluids and 1/4 tank of gas... input that with my best 1/4 mile time and trap speed in 2 different calculators and they spit this out http://www.4racecars.com/calculators/horsepower_calculator.html Horsepower Results - 1/4 Mile Method Your 260z weighs about 2850 pounds and can complete a 1/4 mile in about 11.138 seconds. That means that you've got about 407.67 HP at the wheels, and about 529.97 HP at the flywheel. http://www.corral.net/tech/horsepower.html The Corral - Horsepower Estimator Your trapspeed was 121 miles per hour and your vehicle weight was 2850 pounds. You are making 402 hp. the gtr is rated at 280 HP stock all bottled up in the GTR. ALL i did was ad an aftermarket intercooler, big exhaust and open air intake on turbos. im running stock booste, stock injectors stock everything does this sound right? 529HP at the flywheel!!!!! i was thinking more like 350 at the wheels. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted January 9, 2002 Share Posted January 9, 2002 The formula I use spits out 413rwhp. I prefer that formula because it takes ET, MPH and weight into consideration. Most of the others calculate HP based on ET or MPH and if you have a bad launch and get a slow ET but high MPH, there is a disparity between the 2 calculations. However, all close enough as long as you consistently use the same formula. They appear to use a 23% loss to calculate flywheel HP. Even using a conservative 20%, I get 516.25 at the flywheel. Why are you so surprised? I love applying the HP formula to some of the ridiculous claims you see in the auto rags. Quote Link to comment Share on other sites More sharing options...
240Z Turbo Posted January 9, 2002 Share Posted January 9, 2002 Well, I ran 120.2mph, but only a 12.2 because of a crappy 2.14 60ft. Scottie calculated something like 362hp@wheels. BTW, are you using the "Stealth" method for determining the hp@flywheel. There is no way you are losing 100hp or so through the drivetrain. That is silly! You need to assume on the order of 12% with your setup, RWD in 4th gear. So you might have something like: HP(flywheel)=HP(flywheel)*Drivetrain loss + HP(wheels) HP(flywheel)=463 Actually, I do not believe this is the correct way to determine the hp@flywheel. I remember there is a different formula and it is not as straight forward as I have shown above. There has been some discussion in the past regarding drivetrain loss on RWD and FWD cars. It is said that FWD cars are on the order of 5% loss and RWD are on the order of 12% with both in 4th gear. BTW, Scottie will need about 530hp@wheels to beat my car! SUCKA! Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted January 10, 2002 Share Posted January 10, 2002 Come to think of it, who cares about flywheel HP? Thats for the watercooler and brag racing. 530hp? Oh, you run hi-9s? Get your butt down here or lets get together at Bradenton for a Sat morning T&T. Quote Link to comment Share on other sites More sharing options...
stony Posted January 10, 2002 Author Share Posted January 10, 2002 scottie im surprised cause i always thought the 280 rated horsepower in the gtr is supposed to be flywheel ( i think ). and to get it up near 500hp with just EMS, intercooler exhaust and open intake is pretty amazing. especially since there is alot more left in it with upping the booste a couple points and adding more fuel dont you think. BTW hows your corvette rear coming. i decided to go with a ford nine inch and gonna try to run 15x15 in the rear. this alone should get me in the 10s Quote Link to comment Share on other sites More sharing options...
Guest Tim78zt Posted January 10, 2002 Share Posted January 10, 2002 Stony, I've always thought GTR hp was measured in DIN, like Porsches. But I don't know for sure, and if that's true, I don't know how to convert the numbers for a better comparison. Just a thought. Only reason I mention it was I just finished reading about the Ruf Rturbo in the Feb Road&Track and they quote HP in DIN. Tim78zt (only 230rwhp and 12psi, but 275 ft/lb!!) Oh, that reminds me of something!!! Why do Supra engine seem to put out more HP than torque, and Datsun L6s put out more torque than HP? Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted January 10, 2002 Share Posted January 10, 2002 How much more boost and timing are you running over stock? Even if you ran the same amount of boost, doing it through a more efficient I/C and with better fueling and timing, the HP increase is surprising. Case in point, the GN engine is rated at 247hp at 12psi boost. With a more efficient I/C, more agressive fueling and timing, a bigger turbo and race gas, I can double the boost and make 420+rwhp and 500+lb/ft of torque. Just control detonation! Quote Link to comment Share on other sites More sharing options...
pparaska Posted January 10, 2002 Share Posted January 10, 2002 Great point ScottieGNZ, about boost, intercooling, HP. Boost is in some ways a measure of the restriction in the intake tract after the engine has ingested all the air it can. If you had a few huge turbos on even a small engine turning even high rpm, the boost would be larger with a restrictive intercooler, piping, TB, manifold, head ports, etc. than with all those areas enlarged but making more power and torque. The effect of actually cooling the intake charge is yet another reason that boost is not really the only thing to look at for power production - a better intercooler will have less loss and more heat rejection, making more power with less boost indicated at the turbo. New idea I'd like to see addressed: I've heard that larger combustion chambers, even with the attendant lower compression, allow for more power production, since there is more room for the mixture above the piston at all times in the induction and power stroke to make power with. So a lower static compression, but running the same cylinder pressure dynamically with more airflow from the turbo(s) could give more power? Does this make sense? Quote Link to comment Share on other sites More sharing options...
240Z Turbo Posted January 10, 2002 Share Posted January 10, 2002 pp, you are correct. At the same dynamic compression, a lower static compression motor will make more power. Quote Link to comment Share on other sites More sharing options...
stony Posted January 10, 2002 Author Share Posted January 10, 2002 scottie running lots of retard due to the stock injectors start to lean out early. not sure on the exact numbers its been a while since i looked at it. once i get the bigger injectors ill be able to mess with timing and booste. the fuel curve was setup with minimal tuning. once the bigger injectors go in gonna run it through the rpm fuel setup with no booste and then setup fuel with booste. I have A/F ratio meter now it should be alot easier. Quote Link to comment Share on other sites More sharing options...
pparaska Posted January 12, 2002 Share Posted January 12, 2002 quote: Originally posted by 240Z Turbo: pp, you are correct. At the same dynamic compression, a lower static compression motor will make more power. So is it possible to get good low rpm torque and throttle response with the lower static compression setup, say 7:1? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted February 2, 2002 Share Posted February 2, 2002 Hello all!! In response to the original post on this thread, ... 400+ HP from an RB-26,... It is my understanding that the Japanese government has a "gentleman's agreement" with the car companies (and/or the insurance companies) that "276 hp" is the maximum allowable horsepower for cars. Realistic hp figures for the skyline (if you wanna search the web, and use your calculator to see what the actualy hp numbers are, that would be nice) say it makes something more like 320 or 350. There! The little information I have in my head is now in the computer! Jarrod Quote Link to comment Share on other sites More sharing options...
stony Posted February 2, 2002 Author Share Posted February 2, 2002 want2bz.... this is coming from me... used to live in japan. the gtr bone stock is real close to that HP limit. but all it takes is aftermarket airfilter, exhaust and a computer tune and its up above 350. i think thats what your talking about. I cant remember the formula but the japanese rating of PS is very pretty much the same as hp. for every 100PS there is a difference of maybe 3 HP if i remember correctly. My Motor is bone stock with the addition of the above and an intercooler and SDS, and the injectors are maxed out half way thru 3rd gear. these engines actually require at least a 550cc injector running stock booste!!!!! Nissan detuned the hell out of these engines. Anyways im ramblin l8rz stony Quote Link to comment Share on other sites More sharing options...
stony Posted February 5, 2002 Author Share Posted February 5, 2002 I was thinking..... 2850 dose that sound right i thought the Zs were lighter then that... What does your Z weigh. Quote Link to comment Share on other sites More sharing options...
Guest MegaShaft_2000 Posted February 16, 2002 Share Posted February 16, 2002 Originally posted by stony:the gtr is rated at 280 HP stock all bottled up in the GTR. ALL i did was ad an aftermarket intercooler, big exhaust and open air intake on turbos. im running stock booste, stock injectors stock everything does this sound right? 529HP at the flywheel!!!!! i was thinking more like 350 at the wheels. The "280" hp claim for the Skyline is a bogus number meant to satisfy the 280 HP limit that Japanese carmakers are supposed to follow. I was reading a site about the Skyline, and the Skyline owners who dyno'd their cars were getting more HP at the rear wheels than the car was supposed to have at the flywheel. About those HP calculators, that first link is way off. The driveline loss they use is way too high. It all depends on the transmission you use, but my car for instance is known to have an 18% loss. Quote Link to comment Share on other sites More sharing options...
Mack Posted February 18, 2002 Share Posted February 18, 2002 Hey Stony, just out of curiosity, how much do you figure you have dumped into your car? when all is said and done, that is? and how much of that went to just swapping in the motor? I am considering an RB26DETT for my 240Z, was looking at L28ET, but the WOW factor and insane HP levels atracted me to the RB. Also, I am on freshalloy.com as well, aren't you ekisela over there? was wondering, all GT-r's came with LSD R200's front and rear, correct? so, could you take the LSD guts out of the front diff (oil pan) and put them into an R200 for a Z? may as well use ALL the part, huh? thanks in advance, McAdam Majors Quote Link to comment Share on other sites More sharing options...
stony Posted February 18, 2002 Author Share Posted February 18, 2002 alot more then i wanted to. If i were to do it again i would look for a rolling sheel that has a cage in it allready and needs no major rust repair. the drivetrain from intercooler to r-200 LSD cost me 450000 yen or 3300.oo US. add another 1500+ for engine meanagement. 1000 for custom exaust,(includes labor at a very freindly rate ;>) dont get scared now.... the entire project is around 20 K now but should be around 13-14K due to a expensive body restore.... check out my web page for the before the bodywork pics !!!! never been to the other page you mentioned always go by stony ;> Quote Link to comment Share on other sites More sharing options...
stony Posted February 18, 2002 Author Share Posted February 18, 2002 ive heard of guys putting the r-200 LSD in teh front of the gtr i guess its stronger then the stock gtr front diff not sure about the rear Quote Link to comment Share on other sites More sharing options...
stony Posted March 1, 2002 Author Share Posted March 1, 2002 my favorite icons ;> Quote Link to comment Share on other sites More sharing options...
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