[95240sr]

im looking at having my motor rebuilt this winter(redtop sr20det) with all new internals. after im done and get new turbo i am looking to be at 400-450 rwhp, i currently have an SAFC 2, will this be good enough to control the fuel. im thinking tomei 740cc injectors and a fuel pressure regulator also. thanks for the help.

 

[nismo200sx16]

APEXI power fc would be your best option

 

[95240sr]

yeah a power fc would be great except for there is no one around here that knows how to tune them and i have heard that you will need proffesional tuning. they are also a little over my budget

 

[Joel]

I wouldnt use the safc2 with 740's. go an aftermarket ecu like a Wolf, Haltech, Autronic, Microtech etc

 

[95240sr]

alright thanks for the info, also do you think that 740's are to big or does that sound about right? then also on my car the pipe running from the turbo to the down pipe hits against the side of the transmission at certain rpm's, has anyone had this problem and is there a way to fix it?

 

[Joel]

You could get away with smaller but for 450hp it sounds pretty good.

This can happen if you have a broken engine mount. Have them checked out. Replacing them with a solid or low stretch/high density mount could solve the problem.

 

[nismo200sx16]

740 sounds a little big. 650cc or 62 lb would be better. the calculation to figure injector size is lb of fuel per hour= expected bhp x 0.55
# of injectors
to get that in cc's mutiply by 10.5.
I got that info from the book MAXIMUM BOOST by corky bell. you should check it out its a good book lots of good stuff.
the fc comes with a base map and is not that hard to tune and you can find it for around $1000.

 

[95240sr]

thanks for the help guys, im not sure if i will go with the power fc or a new ecu. i would like the power fc if i am capable enough to tune it on my own, otherwises it will be the new ecu. as for the injectors i am probably gonna stick with the 740's.

 

[95240sr]

well my plans may have changed a little, now im thinkin about going for about 375rwhp on stock internals, would the safc2 be able to handle 550's or is that a little out of its range. i dont have the money i thought i was going to and this is my next best option. by the way i wont be running that horsepower often, just at the track probably on race fuel. one last question is that i have been lookin at injectors and it seems that they mount up in stock fuel rail, am i correct?

 

[ByReaL]

740 sounds a little big. 650cc or 62 lb would be better. the calculation to figure injector size is lb of fuel per hour= expected bhp x 0.55

sory for the OFFTOPIC but i have a qestion

the price of 650cc injector or a 740cc injector or a 1000cc injector is not much diferent

lets say i buy directly a 1000cc and i want to have only 300HP,

my qestion is :
will be a lose of power because of oversized injectors?, or is just that lost of money (not to big)
any problem if the injectors are bigger then the ones needed for that power?

 

[95240sr]

yes it would be a waste of the extra money and unless you have a standalone fuel management it is going to be running way to rich, with the real big ones it may not run at all because there would be some much extra fuel than needed

 

[ByReaL]

http://www.boostcruising.com/silvia/eprom.asp
i read that webpage (the last part) were it tels how to calculate the new injector konstant

and asuming the CA18DET has 370cc and I bought 1000cc

370 / 1000 = 0.37
12A (298) * 0.37 = 110 = 006E (hexa value)
(read the last part from that link so u can understand the calculation done here)
acording to that web page if i buy and replace the stock injectors with 1000cc injectors, and change in the ECU CHIP that data (i can do that i have all the necesary hardware - and i have also that software) the car should run just fine

true or not?
(to be more specific: if i replace the stock injectors with 1000cc injectors no other mods done to the engine and on the ECU CHIP i change that data acording to this calculation .. the engine will run ok?)

PS: no need to talk about the waste of money, the ideea is that if i buy new injectors and replace the stock ones, to do this like one time job (i replace the stock ones with new ones and even my engine has 169HP or 500HP to be confident that my injectors will do their job - we do not talk about fuel presure fuel pump... only about the injectors)

 

[Joel]

Your idle will be crap with 1000's. If you are only going for 300hp, 650cc will do nicely.

 

[95240sr]

can anyone answer my question about the safc with 550 or 650 injectors

 

[storey]

you can use a safc to dial in 550's(not sure about 650s but i would say no) but if you are planning on 375whp you will need bigger injectors than 550's. 550's with a adjustable fuel pressure regulator and hf fuel pump will start to max out around 300whp. i use 740cc's and i put down 329whp. however you will not be able to use a safc to dial in 740s they are to big. my ecu is rom tuned.

 

[95240sr]

alright thanks for the help, i might go with a power fc or a JWT ecu. it all depends on my money situantion