Vortec or AZ Speed EFI Enhancements

[Voodoo]

Has anyone tried either of these EFi upgrades? Did you see the 2-5 MPH increase. If not was it worth the money?

[B-rad502]

Well, I did the EMI headers, Flame arrestor, adjustable fuel regulator, and the re-programmed ECM. We ran 3, maybe 4 mph faster on the speedo. I had to get the timing adjusted from 8 up to 10 degrees. If I did it again, I would not touch the computer. It was nice running 87 octane and now I can only run 92. That proved to be a hassle at Lake Powell. I really don't think the computer made much of a difference. In fact, I'll probably have it re-done back to stock settings next season. The headers and flame arrestor, I would DEFINITELY recommend though. The boat is much quicker to plane and the mid-range showed the most improvement. I don't think those findings came from the computer. The only thing I have left to do is get a good fuel pressure gauge to maybe adjust the fuel some more. If you're in the market for EMI headers, call Don Baca at Triad Performance Marine. Excellent service from them. www.tpmarine.com (http://www.tpmarine.com)
In summary, you're going to spend less money and have really worth-while results by just doing the headers, arrestor, and maybe the regulator. You could do all of this for under $1,500 total! The Vortech kit is about $1,000 and does not come with headers.
Good luck!

[Voodoo]

What did you do with the fuel pressure? Do you need to increase it with the headers and flame arrestor?

[B-rad502]

Right now, we have it set at 44 psi (at idle). The stock setting from merc on a 2000 502 is supposed to be 43 psi + or - 2 psi. It runs real good where it is now and I think there is room to bring it up some more. I just don't have the computer they plugged in at the shop and have not put together a gauge to plug into the fuel rail. Hopefully we can play with it at Havasu next month. I have heard that the pressure will be off if you add the headers and arrestor without addressing the fuel pressure.
Originally posted by Voodoo:
What did you do with the fuel pressure? Do you need to increase it with the headers and flame arrestor?

[SUPERCREWJOHN]

Is their a kit like this available for the 496HO? I guess I would like to run just a bit harder than everone else in the midrange to lug my poundage around :-P
Originally posted by B-rad502:
Right now, we have it set at 44 psi (at idle). The stock setting from merc on a 2000 502 is supposed to be 43 psi + or - 2 psi. It runs real good where it is now and I think there is room to bring it up some more. I just don't have the computer they plugged in at the shop and have not put together a gauge to plug into the fuel rail. Hopefully we can play with it at Havasu next month. I have heard that the pressure will be off if you add the headers and arrestor without addressing the fuel pressure.

[B-rad502]

Have not heard of one yet for the new 496. I'm sure they are working on it. They do have K&N filters for that engine at Rex Marine. That plus a good set of headers will get you some extra punch. Good luck. http://free.***boat.net/ubb/smile.gif
Originally posted by SUPERCREWJOHN:
Is their a kit like this available for the 496HO? I guess I would like to run just a bit harder than everone else in the midrange to lug my poundage around :-P

[MNLavey]

We just finished ours this weekend on our 454 Mag... We ended up getting 2.2mph on the GPS... Midrange and throttle response seem better, but that's just seat of the pants...
If I were to look do it again, I'd seriously look at Vortech... We ended up using their instructions off their web page, because they were WAY better than what we got from AZ Speed and Marine... JMO...
We also are having some discussions on the fuel pressure... We are currently setting it by turning the key to the on position without actually starting the boat. At first it jumps to 46psi, then settles in at around 42psi... We got a couple different answers from AZ S&M on this, but this seemed to be the one they thought was best... Thoughts???
Mike