Is this fuel system set up safe for 9lbs of boost?

93RiceKillinGT

New Member
Jul 15, 2003
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somers Ct
I am currently running a 306 with Gt40-y303 heads, cobra intake, my cam is a comp cam .533/.544 lift with 215/220 duration, 114*, with 10* of overlap. I am useing a C&L 73MM MAF calibrated to 24lb/hr injectors with a 155 lph fueld pump.

Im going to bolt on a rebuilt powerdyne BD11 with 9 PSI boost with an MSD Boost Timeing Retard unit. Im not planing on going crazy with the engine as in bringing RPMS over 5500 or drag raceing every day, maybey 2-3 times next season. With a safe tune will I be able to get by with my set up of injectors/maf/& fuel pump? Also with the cam I have now will it do a good job of bleeding off some of the cylinder pressure, in other words will I actually see 9psi or something like 6-7 becuase my engines breathing efficency is up?
 
I would say use a 255lph pump with a good fmu with about a 6lb disc and you will be fine. I have seen lots of cars at the local dyno that do just fine with "small" by stangnet standards injectors. Lots of people don't like fmu's and buy bigger injectors and then get a custom tune because lots of times an fmu will cause an extremely rich condition. I would rather spend $40 on an fmu disc than $500-600 for a custom tune on top of the cost of having to buy 42lb injectors and another mass air meter. Just my thoughts though, I'm sure someone will disagree. I've just seen lots of cars on the street that run real strong using an fmu.
 
With an FMU you will need a pump that will support the 50-60+PSI load it will put on your system. Going with the larger injectors/custom tune will keep the fuel pressure at the stock settings.
I suggest getting an inline booster pump and spend the $ on some dyno pulls where the A/F is monitored, just to make sure you don't break something.
 
I am adding a 5-6psi Vortech V1 SC-Trim (with a boost pipe bringing boost up to around 8 or 9psi) and I have been advised to do a 255lph pump and 42# injectors. Smaller injectors with an FMU could work, but the 42# ones will allow bypassing the use of the FMU.

Also, that C&L MAF may be an issue. Mine has been fine for my n/a setup, but I am stepping up to a Pro-M 80mm short style MAF for the blower setup.