260 Guru's

[WaterBoy]

I boat a newer boat about two months ago. I just purchased a DDT and was checking my ECU and everything passed. But, I was expecting it to be set at around 99 or 101. It said 83. I turned the set screw and the number went up, also the set screw was turned counter clockwise all the way. My pyro's show at 5500 at about 950. This is an A-63 box on a stock short shaft 260. Any input would be great. It just don't sound right. That just seems tooo lean. :confused:

Waterboy

[johnnyracer]

Just as a fyi. I had one go full lean a long time ago (a-63) and it wouldn,t even run good enough to hurt itself. How is it runnin? Are you just easin it or rompin on it. If it really is set that lean I wouldn,t think it could leave without falling on its face when ya stomp it.

Interesting problem. please keep us informed.

Later Johnny

[WaterBoy]

It's runnin good, that's the problem, I wasn't worried about nothing till I checked it with the DDT. I'm thinking of changing it to 99 and seeing how it runs and watching the pryo's. It's got me wondering what is going on. I've heard of them going full rich, but the sensors and all passed according to the DDT. :confused:

Waterboy

[johnnyracer]

You said everything passed on the meter. Is that including the prom number?

If you can read the pulse width on your ddt , maybe you could compare your numbers with that of another a-63.
Just a thought . I,m huntin here;)


later Johnny

[boatless]

Jason sent the original chip and regulator out today. You should have it in the next couple days. When I bought that motor I talked with Brad at Mirage and he suggested trying the chip that is in the box now. I never checked the #'s on the DDT but the boat did seem to run better on top. Don't know if that helps or not.

greg

[Bill Gohr]

it was so lean it didn't make any power, no power, no heat

[WaterBoy]

The only thing is the motor is runing great. When I make a short pass across the sandbar, at the end when I start to let off the pyro's are at about 1100 and that's about 8900 rpms.

Waterboy

[dennymac]

it, but i can't imagine not toasting your engine if you went cruising around on an a-63 chip set on 83...if i was you, i'd check your ecu and your calibrator against a known good one...dmac

[WaterBoy]

I don't think it's the DDT, I got it from MTCM and he always has good things when he decides to sell them. I'll recheck it with another DDT, but I don't think that is the problem. Who knows?

Later,

Waterboy

[Rodney Nance]

Might need to check it. If for some reason it had more pressure than it should the box would have to be set leaner to compensate.

[johnnyracer]

Is this an A-63 with an after market chip in it or what ? and did the ddt identify the chip as being for an A-63?

Johnny:)

[WaterBoy]

This is an A-63 chip, I called Bill Gohr when I bought the boat and give him the number on the chip. Bill said it was an A-63 and to set it at 97 and go. The DDT also identified the chip as being a 96 drag A-63.

Also, the fuel pressure gauge in the dash says 50 to 55lbs. I know all gauges are different but it isn't showing it over 60lbs.

Thanks Again,

Waterboy

If I have time Turkey day, I'll run another test with the DDT with the motor running and check the pulse of the injectors at 83 and then at 99 to see if there is a difference.

[dennymac]

can go bad...somethin isn't right...you aren't riding around on an a-63 set on 83...there aint no way...dmac

[WaterBoy]

I know something isn't right, that's why it's posted to try and find out.

The prom ID number was 2796. I remember the Batt. volts was 12.0 and the throttle pos V was 0.83. And the map sensor and all said passed. I'm gonna check it again like my previous post because another friend wants to know the injector pulses and some other things.

Waterboy

[Bill Gohr]

did you check the air temp sensor in the block? What does th emap sensor do at ambient and does it change when the engine is running. Again look at the pulse width when you adust the trim screw make sure it changes. I had an ECU here that the trim adj was screwed and you turned the screw and nothing happened.

[johnnyracer]

Hey Waterboy . Did you figure it out yet? The suspense is killing me:D

Later Johnny

[WaterBoy]

I haven't even messed with it since this came up, maybe this coming weekend.

Waterboy

[WaterBoy]

I brought the boat out today and checked a few things.

While running,
Engine RPM 1600
Coolant TMP 70
Throttle POS V .83
Battery Volts 12.5

This is the INJECT Msec:

Set at .83, 1.9 was the min. and 1.9 was the max., this is idling.

Set at .99, 2.2 was the min. and 2.3 was the max., this is idling.

Everything passed when running also.

Any Idea's

Waterboy

[KMA1/4master]

sounds like you are getting all the right answers so far but you need to check your equipment against someone else's for consistancy

[us1]

The A-63 is a Drag box. It runs way richer than a 260 needs so thats why its set to such a low number.

[WaterBoy]

Thanks for the input. But .83 sounds abit lean to me. The box can't be set any leaner than what it is now. I guess, I'll have to wait till later and run the motor on the river with the ddt hooked up and run it set at say .99 or .97 and see how it does. The boat runs good now, if I hadn't bought this DDT, I wouldn't be all this concerned.

What would be a good ECU to run for racing, A-6 or ?


Waterboy

[us1]

A 300 requires way way way more fuel than a 260. The setting sound right to me.

[Bill Gohr]

only reads between 85 and 115? You must have it turned all the way lean. Surprised it runs. Set the box at 97 and find out what else is wrong.

[WaterBoy]

Where would you start looking? I'm going to send my injectors, fuel rail and regulator to be flowed and cleaned hopefully next week. What else would you check?

Thanks, Waterboy

US1, If I decide to tear it down for a rering and to check it out. You'll be getting some pistons for top pinning, if you top pin them, how much for some rings? I thought I heard you say that you had to notch them or something. Or better yet, how much to top pin and rings together? Thanks

[us1]

I'll email you about it. I have a whole bunch of info I send to everyone who asks about it.