I'm thinking seriously about getting 272i/264e camshafts. A while back I read that the conventional wisdom of some was, the stock fuel pump and injectors couldn't handle the fuel demand. Then other guys said it was fine, with tuning. So I wonder, if anyone with a UTEC knows definitively if you can run cams and not bother with a new pump/injectors, or if the demand is so much that not even tuning will keep the fuel in line.

 

The pump is mainly a precaution, gives your fuel system the additional capacity if needed..

Depending on your tune, and boost levels, injectors may not be required.. But its hard to tell because increasing the the cam lift and duration means more air and fuel can get into the combustion chamber, same thing with more boost and other lowering of restrictions.. So as performance increases, so does fuel demand. Its not somthing thats easily determined until you analyze your tune and look at your injector duty cycles, but if you sustain anything over 85% for any period of time, you'd likely benefit from upgraded injectors. Again, it really gives you a little bit of headroom..

I'll let you in on a secret, the bigger injectors early on were a means of reducing the MAF signal on a piggyback setup enough to alter your fuel cut so it went higher..

To make a long story if your engine doesn't have a demand for additional fuel, its not required, especially with the UTEC and open loop fueling. But I suspect you will need them eventually.

 

I have 272/272 cams and I went with the fuel pump as a precaution. As Jack said you will want to look at you injector duty cycle and from that you can determine if the fuel upgrades are needed. So far with my setup I havent seen the need for upgraded injectors.

 

Thanks guys! I guess the Walbro is in my future, with all its glorious noises.

 

I dont even hear mine...

 

After driving my race car around, I find that things like loud pumps and rattles don't bother me at all.. LOL The race car sounded like there was a can opener in the trunk..

The walbro isn't "As loud" as people make it out to being, but for some it can be annoying think of it this way, if you can hear it running, then its working..

 

I have a walbro and i can hear it running, but it not at all annoying....just my 2 cents.

 

Yeah mine can get noisy on certain days but Im pretty much used to it now. My last car the upgraded pump was much louder and you could hear it all the time so I was somewhat relieved when I put the Walbro on the Evo.

 

I was really just kidding. I just bolted down my subwoofer so I doubt I'll be hearing much of anything unless I really want to.