hadleycat

Talked to Crockett today. "He said stop by tomorrow and I can help you out" Sweet!!

ezstriper

without starting a war here...but this is the issue with the merc MEFI systems and not being able to tune on the fly in the boat for the most of the guys...not to many setups/elevations/etc are the same so sending the ECM out getting a tune done and trying, then repeating is a pain. your 80psi fuel pressure is just a big bandaid that procharger tried to no tune was required..again banaid....you need to change injectors/rails, possibly fuel system(not sure what you have done) then work on tune to get it right...my .02 Rob

Griswald

Mefi 4s can tune on the fly with Tuner Pro emulator and/or Mefi Burn.

GPM

So does that mean you can make changes to all of the maps real time while someone is driving the boat ?

Young Performance

Yes, you can tune real time on the fly. I'll drive the boat with the laptop on my lap and tune it while I drive.

As mentioned, you are out of injector. Being a 97, you have Keihin injectors. There are no drop in replacements. However, we have redrilled the intake and fuel rails to accept long Mototron injectors. You can then go to 65 lb injectors (high impedance) that will support all you want to do. You will also need to make some mods to the rail so that I can be fed from both ends. The main fuel passage way in that rail isn't that large, not to mention you can't feed it with large lines or fittings. That is why we feed it from both ends.

80 psi is really hard on the injectors. The pintle has to close against that pressure and it really takes it's toll on them over time. Go to a Mefi 4B so that it can be tuned properly with a more manageable fuel pressure. Not only are you out of injector, but at 80 psi, you are probably at the upper end of what the pump can do. As pressure increases, the volume that the pump moves decreases.

We have done a ton of them. Let me know if we can help in any way.
Eddie

ezstriper

I understand that, what I was trying to get across was the fact of sending the ECM out to someone to tune off the boat and hope for the best when you put it back on...

Trash

Eddie, R/C injection in Torrance has drop in replacements for Keihin injectors in many sizes. I replaced my Keihin with RC units.

hadleycat

Good to know Trash. Thank you!

Tyler Crockett has helped me optimize my current set-up and I am going to run it for the rest of the summer. Running Great!!

I am going to research my options over the Michigan off-season, Which lasts about 9 months, and decide which direction I want to go for future upgrades.

Thank you everyone for the advice, comments, and input! What a Fabulous wealth of knowledge and guys willing to share it available on OSO !

Young Performance

The largest replacements I have seen is 50 lb/hr. We actually flowed some at the shop and they flowed the same as the stock 42's.
Eddie

Trash

I personally took my Merc manifold, TB , and fuel rails to their shop in Torrance and we grabbed injectors off the rack and hand installed them on site. Ran stock injectors through the flow bench and their injectors for a back to back A/ B comparison. Checked flow rates and spray patterns. They have stuff that flows way more than 42 lbs/hr. I am not affiliated nor endorsing but simply stating first hand,. onsite, touch the **** myself information. Use it as you see fit.

I've been running these injectors, my motor, self tuned, for over 3 years now (180 hrs run time). No complaints. Offering this merely as a data point for those in need.