ca18det 67 roadster

[mexican]

i managed to shoe horn a ca18det in to my 671/2 datsun roadster at this point if fires right up and idles perfect but whene you go to rev it up it couphs like loss of fuel.
i have tried 2 different ecu and three diferent stock mafs , the wiring has been checked (several times ) there is no leeks in the intercooler piping.
i was wondering how much psi of fuel i should be running to the engine?
i have a walbro 255 fuel pump should this be enough?
what size fuel lines should i be running?
with the larger intercooler and piping will i need a aftermarket ecu?
any helpfull inpute would be welcomed

[boost_boy]

Be wary of your fuel pressure regulator. That walbro pump tends to upset the stock fuel pressure regulators and over-run them.

[leadpaw]

fuel pressure should be at 36 psi with no vacuum on the regulator. Have you ever gotten the motor to operating temperature? it could be a cold start problem.

[mexican]

Be wary of your fuel pressure regulator. That walbro pump tends to upset the stock fuel pressure regulators and over-run them.

thanks for the info i will check the pressure before the pressure regulator do you know how much pressure is to much ? the motor idles at 800 rpm but soon as i give it throttle it it seams to go up to around 2000 rpm and instantly dies back to 1000rpm and then back up to 2000rpm and keeps on reapeating this cycle this happens even at full operating temp. my first thought was the maf but i have tried 3 different ones and al the same results even tried a different ecu . i do have 21/2' intercooling piping running to a kintech front mount intercooler and 3' running to the throttle body should this make a difference?

[mexican]

fuel pressure should be at 36 psi with no vacuum on the regulator. Have you ever gotten the motor to operating temperature? it could be a cold start problem.

it happens when its cold and at full operating temp it idles at 800rpm when you give it throttle it revs up to 2000 rpm and then dies back down to 1000rpm and then back up to 2000rpm and repeats the cycle i know my maf is good and my ecu is good

[beans33]

Still sounds like a maf related problems. Have you checked the ecu for trouble codes ?

[mexican]

Still sounds like a maf related problems. Have you checked the ecu for trouble codes ?

the code comes up 55 so no problems by the computers . but do you know if the battery was disconected how long after the battery was conected how long will it take the ecu to re read any codes and does the engine half to be running for the ecu to pick up codes .

[mexican]

Still sounds like a maf related problems. Have you checked the ecu for trouble codes ?

the code comes up 55 so no problems by the computers . but do you know if the battery was disconected how long after the battery was conected how long will it take the ecu to re read any codes and does the engine half to be running for the ecu to pick up codes .

going back to square one my ca18det idles smooth no hesitation no stumbeling just smooth whene i rev it up it 0nly goes back and forth from 1800 to2100 rpm at a even beat aprox 75 peats ber min this is what i have tried so far

tested intercooler and piping (good)
replaced all fuel lines with 5/16" lines
tried 3 different stock mafs
tried 2 different stock ecu
tried different thottle sensor
checked the compretion on the fuel system (good)
checked for vacume leeks (good)
timing (good)
fuel tank was cleaned and 94 oct fuel added

i think i have narowed it down to injectors i checked the spark plugs and they were all black (to rich) they are stock 370cc injectors .

i hooked up my timing light to a injector and discovered that the injectors have been cutting out witch is creating my pulsing rev.

DOES ANY ONE KNOW WHAT WOULD CAUSE THE INJECTORS TO CUT OUT COULD IT BE THE DROPPING RESISTOR? I ALREADY TRIED A PROVEN WORKING ECU WITH NO CHANGES IN RESULTS.