95m3 dme on m50tub30 and boost ??

[M3blitkrieg]

I just bought a relatively newish built m50tub30 stroker engine I found on the fly from a guy going s52. It came with a stock red label dme for the original 2.5l that i guess runs it. The current project I am interested in is the Eaton m90 thing.
To remain as "budget friendly" as possible I would Like to remain at the stock dme. From what I read on here a stock dme can handle 5lb boost flow. Does that apply to the 3.0l with red label ecu or would I have to convert to a 95m3 3.0l dme and see if that can take 5lb boost without a tune? If not? What would you suggest is the cheapest solution/setup to accomplish this. (Eventually going to go big sc) thanks ahead of time for dealing with my newbieness!

[pbonsalb]

I would not. Would be a shame to wreck the motor due to detonation from running lean or insufficient timing. I am assuming the 2.5L tune was changed to a 3.0L tune. But if it is using the 17lb injectors used on 92-95 325i and 95 M3, they can't support much more power than a 95 M3 makes. If it has the 21 lb injectors from a 96-99 328i or 96-99 M3, they might barely be ok for very low boost on an otherwise stock 3.0L.

Higher cylinder pressure from boost requires less ignition timing. This must be changed in the tune.

If you had a $500 M50 or M52 and did not care about blowing the motor and swapping in another, I'd say buy a rising rate fuel pressure regulator and try it. But if I cared, I would not. You may get lucky if the knock sensors pull timing quickly enough or you may not.

[M3blitkrieg]

Thanks for the quick response. What would you recommend for tuneing? Flash dme? (Maybe I can find a local shop) or a second or replacement ecu? Thanks again.

[pbonsalb]

Try asking for obd1 tuners in the Forced Induction subforum; I think you can just swap the chip in the early ECU.

One issue is that what you want -- a cheap tune using cheap parts for low boost -- probably does not exist. There are 6 psi centrifugal tunes floating around using larger injectors with the stock HFM but they won't be mapped well enough to handle boost at low rpm because centrifugals don't make any boost at low rpm. A turbo tune has to be mapped for boost at lower rpm, but maybe not very low rpm. It is possible a turbo tune would work. Ideally, someone may have a copy of an AA or Eurosport twinscrew tune. Many of these tuners are starting with tunes they copied from someone else that they then modify a little. If you use an existing tune, you have to use the hardware specified for it, meaning injectors and HFM. It will be cheaper to buy those parts than to bring your own parts in and ask for a custom tune, since custom tuning requires dyno time and dyno time and tuning time is expensive.

This is one reason why oddball projects can be an expensive pain in the rear. Once a project has been done a few times and the issues worked out, it becomes easier and cheaper. Once someone has spent the time and money on developing a tune for a project, the tune can be copied cheaply and resold to recover the initial investment.

[328 Power 04]

What you are forgetting is that it's not the ECU that is really giving you the "5psi limit"... it's the MAF capacity and the injector size.
And then the ECU control is just not going to cut it without a proper tune. There are many more factors than just adapting fuel quantity for the increased air..

[M3blitkrieg]

Alright, I think I see what you guys are saying. The stock parts aren't capable of adapting to my wants. So in the end the project is more than what some claim as a parts change and magic "budget" HP gains.
Am sure my novice in the area is about to show but, what do I need to overcome this dilemma? Aftermarket ecu? (I guess I need to learn to tune myself if tunes are that costly).
After that I guess I could mimic some turbo builds parts list for maf and injectors? What's the most introductory aftermarket ecu that has some sort of instructions with it. I would like not having to ask a bajillion questions about it. Thanks again. I really appreciate your detail orientated info. More I learn the faster, easier, quality is in my project.

[jakermac]

You don't necessarily need a chip burner or multiple chips to tune an OBD1 car. I've been running a Moates Ostrich 2.0 in my car for the last year. It's a chip emulator and is re-flashable just like an OBD2 car. I just plug my laptop into the USB plug that is coiled up in my glovebox and I can re-flash the DME (actually the chip emulator) as many times as I want. The actual flash takes about 10-15 seconds. Sure makes it a whole lot easier to tune an OBD1 car.

http://www.moates.net/ostrich-20-the...eed-p-169.html



You could learn to do your own tuning on OBD1. There are several resources out there to help you with what you need to learn and what parts you should buy to do the job. There are also several competent tuners out there that could help you with providing a tune and revisions. My personal favorite is Zack Schaper of 22nd Productions (22rpd.com), also known as Vollosso on here.

[M3blitkrieg]

Do you have idea where I could find the info about what tuneing stuff I need? Figured this was the place to ask with it being the tuner section.

Cables, what programs,laptops(tablet would be cooler). I just don't know,what it is i am looking for really.


I think after reading the ostrich site, I've realised how clueless I am on this subject. No idea what Japanese crazy talk, but the price looked cheap. Still don't know what it does.

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Ok. So I need a kit or package to tune for the m50b30 na that can,be adapted to boost later on. I looked at war, bit it looks like high boost only?

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Ok. So after hours of intense reading I see that there is no cheap way into this. I think tuner pro and ostrich are simply not a good start for me. I think i Am going with a miller war chip. Or WAR. Probably the kit. From what I see as actual viable options its that, or go stand alone. And i don't see alot of beginner friendly in megasquirt tuning. Unless iAm missing aomthing with it?

[jakermac]

Ok. So after hours of intense reading I see that there is no cheap way into this. I think tuner pro and ostrich are simply not a good start for me. I think i Am going with a miller war chip. Or WAR. Probably the kit.

Be warned. A few of us have experienced weak spotty support from Miller on their War chip setup. And the learning you will inevitably have to experience with War chip will be the same as Tunerpro, etc...

[M3blitkrieg]

Hell.. I just want quality.. I read the ostrich can have problems with losing tunes and stalling cars. That tuner pro is a second hand product. ... ... I feel that its impossible to judge what is a good product to buy. .. Im not looking for a argument on what is better or easier.

Can you lay out strong points vs weak points of the options? What did you find to be the best for you and why?