Switching from 3.0 to a 2.75 pulley. How Much power will be gained?

ADRENLN

Active Member
Apr 16, 2003
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NJ
Hey guys, april second my car goes back into the shop to fix the tune up. my sig has stated forever that i was still trying to get the tune right even with the numbers i get now. anyway, while it is in there i figured id do a smaller pulley swap. im going from my 3.0 which made the power listed in the sig at 6000 rpms. this time i will be able to rev to 6500rpm provided they figure everything out. i realize that this in itself will make a little more power as it sits. however, i am going to pulley down to 2.75 and slap on a bigger fuel rail kit.(dont know if the fuel rails will help power any)

so a couple of questions:

first, what do you think just the 3.0 to 2.75 pulley swap will make boost and power wise?

second, what do you think rwhp will be after all is said and done considering there was about 500rpm left on the table last time?

third, will the bbk fuel rail kit effect horsepower in any way?

thanks guys.....lets hear the opinions!
 
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The fuel rail kit won't do anything except add more complication and money to your system.

Oh, and I think you'll gain about 80 rwhp and 4 psi with the added rpm and smaller pulley. Who knows, maybe you'll get an even 600 to the wheels.
 
damn, more complication is not cool...lol however, i did order it already. i figured that at my hp levels it might be benificial and maybe that is why i was having some difficulties tuning. also i am going to get a aftermarket intake in the future and figured that i could already have the fuel rails. maybe i figured wrong?! anyway, i could only hope that the pulley down to 2.75 would add that much for me!!!!! hope your right.

who else has some knowledgable guesses and some insight? thanks
 
i'm running a 2.75 pulley but i'm overdriving it 10%.

last week i saw 22 psi on the boost gauge. take away the 10% and that would be roughly 20 psi you should make

you need rails over 550 IIRC. also i bet your cobra pumps will be maxed out. i maxed out GT pumps on my street tune and needed a BAP to keep it safe. make sure to datalog the duty cycle when the pumps are HOT, not just a cold pull. BTW did you do a wire upgrade for the pumps and a PPRV delete yet? if not i would add that to the list before it is tuned. you will be on the ragged edge of what the cobra pumps are capable of.

the fuel rails are simple. nothing complicated at all. just need a couple of fittings for them to bolt on.

i'm gonna say the power should be around 575 to the wheels IF you have the fuel to support it
 
wow, great tips saleen! thanks! thats is what i need to know. i do have the boosta pump set up with the cobra pumps. i will have them data log the duty cycle of the pumps while they are hot rather then cold. i do not have the wire upgrade for the pumps and a PPRV delete yet. where can i get that stuff? i guess they will have to tear into the fuel takn again to do that right? is it a lot of work/ labor intensive?

thanks
 
wiring upgrade helps with voltage drop when you are running 2 pumps on the tiny stock wires. the PPRV delete takes out the valve that dumps fuel between shifts causing a hesitation and also takes away a big restriction in the line
 
wiring upgrade helps with voltage drop when you are running 2 pumps on the tiny stock wires. the PPRV delete takes out the valve that dumps fuel between shifts causing a hesitation and also takes away a big restriction in the line

So since I'll be running mu return system, it shouldn't matter if I do the PPRV delete then?
 
thanks again man for the links and the info. ill have to read over it again when im sober but i think i am going to go with one of those modified fpmd form lethal performance with the wiring upgrads. i know it will cost me more but i wantto get everything ready quick before it goes in the shop. i just think it will be a bit quicker and easier. i will look at the pprv delete though. do you think that sounds ok despite the money?
 
the driver module is a great addition. i have a stage 2 driver on my car.

IIRC the upgrade is only about $150 if you send them your FPDM and have them mod yours rather than buy a new one

Zone 5 is the place that did mine
 
I sure hope you are upgrading to 8 rib or already have. On my novi I ran a 2.8 with 10% overdrive and saw 23lbs. On the your engine the same pulleys will probably net you 24-25lbs. But the 2.75 and stock crank will slip like crazy with a 6 rib. If you get the belt to stick you will see 18lbs which on your engine will be good for 600-620rwhp.
 
holy shi! oxford!!! what! i do have the 8 rib set up already. however, what makes you think my engine will see more boost then yours did? i will not be doing a overdrive pulley just the 2.75 novi pulley with the 8 rib. my tuner said they think i will see about 16-17 psi. right now i have the 3.0 on the car and only see 14psi. i would love to make that type of power but i dont think it will be that high...i could only hope
 
wow that was more then i was barganing for. well i guess after i get all this taken car of i will get an intake and open things up a bit. i also want to get stange 2 blower cams from mph but that ill do way down the road when i feel like paying 1000 bucks labor to swap. thanks for all the info guys i will keep you updated
 
Hey guys, april second my car goes back into the shop to fix the tune up. my sig has stated forever that i was still trying to get the tune right even with the numbers i get now. anyway, while it is in there i figured id do a smaller pulley swap. im going from my 3.0 which made the power listed in the sig at 6000 rpms. this time i will be able to rev to 6500rpm provided they figure everything out. i realize that this in itself will make a little more power as it sits. however, i am going to pulley down to 2.75 and slap on a bigger fuel rail kit.(dont know if the fuel rails will help power any)

so a couple of questions:

first, what do you think just the 3.0 to 2.75 pulley swap will make boost and power wise?

second, what do you think rwhp will be after all is said and done considering there was about 500rpm left on the table last time?

third, will the bbk fuel rail kit effect horsepower in any way?

thanks guys.....lets hear the opinions!

The fuel rail kit won't do anything except add more complication and money to your system.

Oh, and I think you'll gain about 80 rwhp and 4 psi with the added rpm and smaller pulley. Who knows, maybe you'll get an even 600 to the wheels.

http://kennebell.net/techinfo/ford-techinfo/DoINeedLargerFuelRails.pdf