550s
- Thread starter sprigmo1
- Start date
crrider80 said:
That doesn't really make sense.
What Ma70 was saying is the stock 440cc injectors are good for around 440 hp, then the 550's are good for 550hp range, etc.
The reason you go to LexAFM is because it flows 25% more air than the stock AFM, and 550's are 25% larger than 440'c. If I'm understanding what you're saying right, the AFM has nothing to do with how much horsepower the injectors can flow.
And the AFM does not change injector flow... Slapping a LexAFM on with the 440's will not change how much fuel the injectors can provide the engine, only the air going in.
Ma70.Ent said:
Actually, the lex afm has mostly been used in conjunction with an upgraded ct26 or larger turbo PLUS 550s and usually something like an S-AFC. Even with a stock turbo you can ruin your engine pretty easily with a lex. You can get some decent gains with a stock ct/440s/lex afm but you should really have an AFPR, better than stock fuel pump, and a wideband monitor (you could get away with an EGT guage I guess). Only a very few people (jblmk3 being one) have really pushed the 440s with a lex afm and he did it with super high base fuel pressure.
As far as 550s go I wouldn't count on the 1cc per 1 hp thing even using flywheel output. With all supporting mods (kind of a long list really) I think you could safely hit mid to upper 400rwhp on pump gas. This is one of those topics that has been discussed over and over and over again so you could get some really good info by searching.
470 flywheel hp is right at about the safe max for 550's in a 6cyl. at 85% duty cycle.
A very easy equation that will get you very close is
inj. cc X # of inj's. / 7 = max safe hp @ 85% duty cycle
so 550X6/7=471.42hp
Remember, this tells you flywheel HP and is for assumed .50 BSFC (brake specific fuel consumption)
A very easy equation that will get you very close is
inj. cc X # of inj's. / 7 = max safe hp @ 85% duty cycle
so 550X6/7=471.42hp
Remember, this tells you flywheel HP and is for assumed .50 BSFC (brake specific fuel consumption)
I'll be running a Walbro 255 pump, an Aeromotive AFPR, Stock injectors (rebuilt), and a stock turbo(also rebuilt) to 14 psi....Should I have any problems? I have a Lexus AFM for down the road and am not sure when I'll need 550's, any advice?
http://www.rceng.com/technical.htm#WORKSHEET
Fuel Injector Worksheet is near the bottom of the page.
Fuel Injector Worksheet is near the bottom of the page.
WeDgE said:
Yeah, but the question was, "What would be safe max HP on RC 560cc injs????"
85% duty cycle is running injectors at a safe level. Sure you can take 550's up to 500+rwhp, but that would be running them at 100% and higher fuel pressure. The key word is "safe".
its not that your math skills suck, its just that you went about the problem the wrong way. you want to find out what is 25% bigger than the 440s to match the 25% bigger AFM. 440x.1.25=[]. 25% of 440=110. 110+440=550.
brainculator FTL!!!
I'm not a fan of the Lex/550 as it's a bandaid of sorts, Cletis maybe?
I mean, it works, and it works well... much better with an SAFCII, but tricking the ECU into thinking that there is less air than there really is, moving the FCO isn't really a good idea IMO...
MafT FTW.
I'm not a fan of the Lex/550 as it's a bandaid of sorts, Cletis maybe?
I mean, it works, and it works well... much better with an SAFCII, but tricking the ECU into thinking that there is less air than there really is, moving the FCO isn't really a good idea IMO...
MafT FTW.
^ That's why I'm saving up for and researching the MaftPro before going that route, I don't want to trick my car so I can shove more "unmetered" fuel and air in.
ok.. So the question is ... If the lex. works good but is not the best way, what is better, 550cc's plus what? assumeing all other upgrades are there for upwards of 450hp, what would you put with the 550cc's to get about 400hp to the tires?