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relation to intake and ecu

1626 Views 5 Replies 4 Participants Last post by  Furious
I noticed that on Dinan's site they say that you should get the software and intake together(basically that the intake NEEDS the Stage2 software setup). Is this the case when doing upgrades of these types on the BMW? '99 328i

It's all a ways into the future but I'd like to get the Benfer Performance intake and probably the shark injection system(no dinan places near me) and wonder if when I pick 'em up if I need to get both at the same time.

Also, a lot of the ECU's programs up the rev limiter...on the auto equipped cars does the car know to use that extra amount?

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Drew - I may be worng but I think the reason that Dinan suggest you get the two together is because Dinan's software is made to take full advantage of the Dinan intake, whereas another ECU programing product may not taek full advantage of it. It could also be a marketing gimmick. As for getting the other two at the same time - it wouldn't hurt. You could always reprogram after the fact, or if you get the software first you could re-reprogram after installing the intake.

It's also my understanding that the ECU will adjust, over time, to the increased amount of air entering the engine without upgrading ECU (considering it SHOULD adjust fuel mixture in proportion to air intake. Therfore greater air intake would dictate different fuel amount to mix. Again I could be wrong, and disapointed if I am. Not about being wrong, but about it not adjusting. But I dogress)). This is not to say that the ECU will take full advantage of ANY intake without being reprogrammed. It (ECU) also will not raise the limiter unless reprogrammed.

*I have to wonder if pulling the ECU fuse for 10 seconds then replacing and starting the engine would cause it re-map the air/fuel mix with the added air coming through the intake*

As far as the auto knowing to take advantage of the new limiter - I have no idea. I would suspect so, as the ECU dictates all that jazz, but can't say for sure.
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Thanks for the reply,

Yah, for all the other cars I've owned I never had to buy a new ECU just reset it for certain modifications. Now if I had purchased larger turbo's for my Z I would have needed to get the JWT ECU but the intake was a mild bolt-on. If anything I'd get the intake first then then ECU. It's a long ways off but wanted to check anyhow.

My guess is that it's a marketing gimmick. An intake isn't going to require an ECU remap to take full advantage of it, it doesn't make enough difference on the overall engine to warrant an ECU upgrade. Now if you got new cams, higher compression pistons, or a supercharger, then yeah, you NEED an ECU remap.
Originally posted by nosuchsol@May 8 2003, 02:55 AM
Yah, for all the other cars I've owned I never had to buy a new ECU just reset it for certain modifications.

Exactly. It's kind of odd that one would have to reprogram the whole system for a mild bolt on like an air intake. Reprogramming after installing new turbos I can understand, considering the ECU would be running fuel maps, etc, for teh specs of teh old turbo(s) and possibly cause major damage.

I reallyhave to wonder if the fuel map in the Bimmers is set with constants for ai/fuel mix or variables. It would be odd if they were constants, in fact it would make no sense to me at all. Eventually it could cause your car to run lean/rich because the ECU wouldn't be adjusting to things like elevation, octane, air volume, poo particles in the air/fuel lines, and your occasional Hydrogen Midget (very dangerous).

Does anyone know if there is another way to tap into the ECU besides the 20 pin round connector in the engine bay?

Good luck Drew.
i think its because they feel that the car could run to lean and not get the proper and full use of the CAI. but thats just a guess on my part
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