Will a 3.0L 250 ECU work on the upgrade?

[FisherBoats]

Thanks to Props4u2 I will be installing a 4 Shutter intake this winter. Now I also know I would need to get my ECU "flashed" or reprogramed for this. Or could I simply drop on a computer off of a 250 3.0L?? And what reeds work the best on these 3.0's?

Thanks!

Jess

[rchevelle71]

Thanks to Props4u2 I will be installing a 4 Shutter intake this winter. Now I also know I would need to get my ECU "flashed" or reprogramed for this. Or could I simply drop on a computer off of a 250 3.0L?? And what reeds work the best on these 3.0's?

Thanks!

Jess

Which motor are you coming from? If it is a 225 EFI, and had 2 computers to begin with then I would have to say yes, if it were carb with only one ECU you would probably need the harness in order to plug in 2 ECU's. I have a set of 250EFI ECU's if you need them.

[FisherBoats]

Yea I am sorry, I have a '98 225 3.0L Mag EFI. I need to either flash both of them or buy 2 250 ECU's? I thought I only had to flash one of them.

[Stitch King]

When I did my 3.0 I found the motor ran better with the 225 fuel and the 250 ignition ecu box. IIRC The 250 Ign ecu has a slightly higher rev limit than the 225 and a higher final timing advance value.

Skip buying another set of boxes and have Simon reprogram the ones you have with the optimal tune for your setup.

[FisherBoats]

Thanks to Chevelle, he can hook me up with 2 ECU's off of a 250. But I would like to make sure I have everything figured out here before I go forward. Now I thought only the Fuel ECU needed to be upgraded not the timing one as well. I just called Simon as Stitch reccommended, and he said that I should go with a 300Promax timing ECU and a 250 Fuel ECU for the specific motor I have. So thanks Chevelle for offering them to me but I am gonna have to pass and send mine to Simon so my motor runs the best with this setup.

You guys are awesome and I am glad you all are here!

Thanks Again!

Jess

[rchevelle71]

Thanks to Chevelle, he can hook me up with 2 ECU's off of a 250. But I would like to make sure I have everything figured out here before I go forward. Now I thought only the Fuel ECU needed to be upgraded not the timing one as well. I just called Simon as Stitch reccommended, and he said that I should go with a 300Promax timing ECU and a 250 Fuel ECU for the specific motor I have. So thanks Chevelle for offering them to me but I am gonna have to pass and send mine to Simon so my motor runs the best with this setup.

You guys are awesome and I am glad you all are here!

Thanks Again!

Jess

No problem,

These are my spares that I took off and went with the 300ign, and 250XB fuel. I like to keep them around just in case anyway, but if someone needs them I will let them go.

[JESTERxHEAD]

see jesse I told you this is the right place to awnser questions.... the SnF crew knows what's up for sure.....

[FisherBoats]

Hey Pete, yea thanks for hooking me up!

[JESTERxHEAD]

np I will give ya a call tonight....

hijack over...

[Stitch King]

Now I thought only the Fuel ECU needed to be upgraded not the timing one as well.

Wayne Taylor (Deceased) had a mantra when it came to the 3.0 liters, "More air, more fuel, more timing!"

What that means is:

1. They are pretty choked off with regard to airflow even with the 4 hole intake.

2. Once more air is flowing in and out of the cylinders you'll need more fuel.

3. The stock timing advance curve is really gentle and the max timing is low.

Keep these three things in mind when building your engine and you will be satisfied with the results.

[FisherBoats]

So the cowling mod will be a benefit then to me as well? I will probably not do anything to the block or heads as I do not want to increase the octane as I already gotta beg the wife to let me fill the boat up every couple weeks lol. I plan on putting reeds in as well while I have the intake out. Anything else I can do to sweet'n her up?

[rchevelle71]

lighten the flywheel, and by the way they are all sisters!!!

[Stitch King]

Yes, the cowl mod is a cheap way to get cooler air in.

Like rchevelle71 said lighten the flywheel. It will help with throttle response.

Reeds will help with idle and part throttle performance.

If you have a Vee Hull and the motor is set deep in the water at idle, Simon's Poppet Valve Dump will help holeshot big time. Checkmate 250 swears by this mod. On a Cat where the motor is not so deep at idle it didn't make a significant difference that I could tell on a Liberator 21 with a 300x.

Cutting the exhaust tuner (aka exhaust can) or installing an aftermarket tuner will help it breath better on that end. This also will help the holeshot. The drawback is it will howl like a banshee at all times.

Higher compression heads will help holeshot. The higher compression won't do much for top end.

Put the entire boat on a diet. Being lightweight helps across the board. Get rid of excess stuff.

[obrien]

What kind of mods are being done on the cowls?

[FisherBoats]

I am running a 21ft Fisher FX21 Bass Boat. I try and keep her as light as I can. Thanks for all the info everyone! Are there better reeds that some others?

[obrien]

I just started a post yesterday asking about reeds. The two that were suggested were the Chris Carson reeds and TDR.

[FisherBoats]

Thanks I will have to look into the 2 of them!

[Stitch King]

I had the TDR's.

Since Chris Carson is a vendor here and there have been quite a few positive comments here you may want to consider them...

[modvp]

This is a great post; I did the cowl mods, higher compression (~121 psi) heads and Chris Carson reeds on my 250 and I am thinking about adding either 250xb or 300 promax ignition and fuel computers or having them sent to Simon for a reflash. The reeds made a noticeable difference in low speed response and idling.