I am currently bored with my 3.12 pulley setup and sick of being stuck at a 13.1 so I want to pull the trigger and buy the 2.87 pulley.

I have a walbro and the CJM Stage 1 fuel return along with RC 440cc injectors and UTEC.

on all of my runs, the MPS Data Logger says my Injector Duty Cycle is only at 19.5 % (unless it is wrong) and i think the top feeds are safe at up to 80% duty.

Does anyone on here run this setup or do you think it will be safe for me to run it?

Thanks

 

19.5% doesn't sound right

 

+1

From what Ive read and what my shop has told me , running less than 60% duty cycle at WOT isnt good . He didnt get into why though .

 

well heres one of my logs

 

Those 440s should be nearly maxed out.

 

what's your FP @ idle on your FPR?

 

~53 psi

 

with the vaccum line hooked up? That's high. Which explains why your injectors aren't working as hard.

 

crap, i knew i did something wrong lol

i measured my base fuel pressure with the vacuum line in

 

What do you mean "stuck with 13.1"?

I know a couple people have 2.87 with 440's and no problems. Timrod is one and he is running the stock Vortech FMU and Aux. Pump.

 

I hope he means his 1/4 mile time. If it's his A/F ratio that is not good.

 

13.1 in the quarters.

I have similar setup as yours with 440cc but aam stage 1 return line and I had to use 2 pumps bc I was maxed out at around 400 with only 1 walbro and 440cc. I would suggust getting 550cc.

 

yeah thats 1/4 mile times, i have it tuned to ~11.5 AFR across the board

 

I would think that as long as your fuel system can meet the demand and it just happens to be at a low injector duty cycle then that should be good. Low duty means less stress/heat, greater reliability and longer life?

 

you will need 550cc for the 2.87 pully. also please dont go BOOM

 

haha i guess i have to wait then.

and i found out that the injector duty isnt in percent on that datalo, its in MS. Even then it still might not be acurate