Alex_V Posted September 28, 2006 Share Posted September 28, 2006 Im kinda in a rush and last time I tried searching for it I couldnt find any thing, Id like to get a turbo for my KA that will max out at about 250WHP and I want to be around 200WHP most of the time. Is the stock L28 turbo good egnough for that on a 2.4L sohc KA? TIA! ~Alex Quote Link to comment Share on other sites More sharing options...
Alex_V Posted September 28, 2006 Author Share Posted September 28, 2006 Alright I found a post where garret made 274HP and 320ft/lbs of TQ. Hmm, thats great, and would the whole power band shift to the left on a 2.4L engine? That'd be perfect, I want to have boost onset around 2500rpm, and making full boost around 3K rpm to redline or near it. does that sound about right for a T3? ~Alex Quote Link to comment Share on other sites More sharing options...
Garrett76Zt Posted September 30, 2006 Share Posted September 30, 2006 Alright I found a post where garret made 274HP and 320ft/lbs of TQ. Hmm, thats great, and would the whole power band shift to the left on a 2.4L engine? That'd be perfect, I want to have boost onset around 2500rpm, and making full boost around 3K rpm to redline or near it. does that sound about right for a T3? ~Alex yes i think you could probably make that power on a SOHC KA with that turbo but it wont be anywhere near the rpm you're looking for. Even that SOHC head flows alot better than our L series heads, however due to the displacement loss, you're still gonna be revving it up to make the power. I would try it out and see what ya get. Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 Stock turbo is a .42/.48, correct? Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 Must be. So you have- 2.4L - 145 cid engine 140hp@5500rpm assuming 85% volumetric efficiency at peak power, thats- (145*5500*.5*.85)/1728 = 196.15 cubic feet of airflow per minute. Since this map uses Lb/Minute, we have to convert from CFM. Which is done like this (A CFM of air appharently assumes its 112 degrees) - 196.15*.070318=13.8 Lb/Min So your KA flows about 13.8 Lb/Min at peek power. 140hp = 13.8 Lb/Min ... Approximately... in your case. To make 250 Hp, thats a 78% increase in flow. We'll say 80% to make it easier. Theoretically, if you double the atmospheric pressure in the intake manifold, you'll make twice as much power. So at 2.0 bar absolute (14.7psi above atmo) youre engine will flow twice at much. Using this reasoning, running 1.8 Bar absolute of boost will give you your 250 Hp. So- 13.8*1.8 = 24.84 Lb/Min of airflow is what youre looking for. Now we can plot these two on the chart- I'd call it too small, the higher efficiency area should be farther to the right. Doesnt look like it would be very well matched for 200 either: 1.42 Bar and 19.6 lb/min. That was a fun excercise. Please correct me if I'm wrong. Quote Link to comment Share on other sites More sharing options...
Guest alex280z Posted October 4, 2006 Share Posted October 4, 2006 what would be a good cc injector to go with my t3/t4 hybrid 280z with 65mm intake, i purchased and planned to use rc 1000cc injectors with low imp. wondering if anyone would have any idea Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 You trying to keep me up all night? What power are you looking to make? Quote Link to comment Share on other sites More sharing options...
Guest alex280z Posted October 4, 2006 Share Posted October 4, 2006 350 hp to wheels pretty much its my toy and i want to go fast i also purchased a fuel pump from a q45 to use with this setup Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 Ok heres how it goes. A turbocharged engine has a Brake Specific Fuel Consumption of .60-.65 . This number can be multiplied by your horsepower to give you your needed fuel flow in Lb/Hr. .65*350=227.5 Lb/Hr of fuel (So Step 1 is a Warlboro 255) Between 6 injectors = 38 lb/hr = 387.6 cc/min 387.6*1.2 (for 80% max duty cycle) = 465 cc/min injectors Whoa thats big... Its meant to be an over-estimate. Does that sound right to other people? Quote Link to comment Share on other sites More sharing options...
Guest alex280z Posted October 4, 2006 Share Posted October 4, 2006 so do you think if i tune properly i can make system work? Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 Tune it using what? Quote Link to comment Share on other sites More sharing options...
Guest alex280z Posted October 4, 2006 Share Posted October 4, 2006 fuel pressure reg fuel management system Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 Oh no not with larger injectors. If youre going to do that you use your stock injectors and the FPR does the rest. Quote Link to comment Share on other sites More sharing options...
Alex_V Posted October 4, 2006 Author Share Posted October 4, 2006 you dont really need an injector bigger then about 440cc and 440cc is common injector so Id go with that. 1000cc is far too big for 350WHP. An observation Ive made is that for 6cyl engines the injector CC is near the crank HP or WHP (depending on the car). Like you want to make 350WHP. Id guess you need an injector about 370cc's. but thats not safe, thats pretty much open all the time at WOT and thats bad. So you add safty with a larger injector, about 20% larger, thats when you get to about 430 or so. 440 being a common size Id try that. Dont take my method as solid advice, it just a simple way for me to evaluate a setup some one has made, real math like what Gavin posted is a better but longer method. Either one has error in it but both are based off real life. As for engine management, your definitly going to want some upgrade Even if its a turbo z31 setup. Id reccomend that or a megasquirt. Both arent too expensive or complicated. Also look at my post on the maxima ECU. Gavin- What about the l28? If Garret is running 275WHP on his and a huge 320WTQ whats the air flow then? It seems 2.8L at 275WHP would put the turbo way out of its effiency range so Id be fine. I wonder whats the max HP I can get out of a KA24E? Should be interesting. time to find out what the l28et flows. ~Alex Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 4, 2006 Share Posted October 4, 2006 Hold on a sec.. Had just done this to size one up for the ZX. Flows about 218 cfm or 15.4 lb/hr, peak power at 5200rpm... The low-comp engine needs 7 psi, or about 1.45 bar A, to make 180hp with the stock setup. So N/A it might make arround 125 hp. So it should take 2.2 bar and 34 lb/hr to make 275hp. That looks a little rediculous. Sure its a .42/.48? And Alex is it DSM injectors that people typically use? Quote Link to comment Share on other sites More sharing options...
Alex_V Posted October 4, 2006 Author Share Posted October 4, 2006 Thats what I was thinking, that graph doesnt suit Garrets HP. It seems it'd be 300+deg if thats even possible. ~Alex Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.