RPI EXHAUST+RPI AIR INTAKE KIT+ RPI ECU

Z

ZM4000

Member
So here's my point i got the RPI exhaust and the RPI intake kit on my Z4MR. On their website they have written that u gain 8hp from ur exhaust, 8-10hp from your air kit. And now i was thinking about reprogramming my ECU because u can gain 22hp ECU+air intake. That means 10-12hp only from the ECU.

I wrote Eloy(RPI) and (Rom3n)ESS yesterday to ask him how much hp i can expect from the ECU now that have allready the exhaust and air intake kit and the answer were different.

Rom3n(ESS) told me that the standard hp gain is 8-12hp but since i have the kit and exhaust he told me that i should have more gains since the ECU reacts to those components.
12hp ECU+ 8hp airkit+ 8hp exhaust=28hp minimum total (i'm happy with the result)
And Eloy(RPI) told me that with the exhaust, air intake and the ECU i should expect a gain of 20hp total :( (i'm not happy with that)
what i dont get is if on their site u read their articles description u should gain 30hp TOTAL with everything installed.

Do u get my point guys???
Who should i choose???? :headbang:
 
The power gains are never cumulative.

The exhaust COULD give you 10bhp, the intake COULD give you 10bhp, the ECU COULD give you 10bhp - however you will never get 30bhp out of the lot.

It works like this because the engine will have a maximum amount of 'extra' BHP it can give out and these mods will be based on taking a percentage of that 'extra' BHP.
So, say this 'extra' BHP is 30bhp and the exhaust claims 30% of that then doing the exhaust alone will give you your 9bhp.

THEORETICAL TOTAL = 9bhp
CUMULATIVE = 9bhp

Then the intake claims it can give take advantage of 30% too, so you think another 9bhp when in fact it's now 30% of 21bhp as 9bhp has already been taken by the exhaust, so you only get 6bhp.

THEORETICAL TOTAL = 18bhp
CUMULATIVE = 15bhp

Then the ECU claims 40% of that 'extra' power and you assume 12bhp, but you only get 6bhp as you've only got 15bhp 'extra' to take advantage of.

THEORETICAL TOTAL = 30bhp
CUMULATIVE = 21bhp

So now your 30bhp power boost is only 21bhp because you've fallen into the tuner trap by 1) believing the figures in the first place; 2) simply adding the numbers up; 3) not understanding how tuning works.

And all that is before you go into where these power gains are to be had, because some tuners will offer a 15bhp power increase but it won't make your peak power increase by 15bhp, it might simply be a 15bhp increase in a place in the rev range where there's a big dip anyway.
 
ok first things first i never claimed to be an tune expert. Thats why i asked in this forum. Thanks a lot for your answer mmm-five.
The i have another question how much hp gains can u take out of your BMW Z4M. without a supercharger
Ok i can live with +-20hp gains.
The i change my question. Wich ECU software is best for or beautiful Z4M.
ESS or RPI???
What are the differences between both?
:fuelfire: :fuelfire:
 
From what I've read the ess tune is pretty good, and message roman and ask him to explain exactly what their software does and how it's flashed. I'm sure you'll get a very detailed answer.


Sent from my iPhone using Tapatalk
 
I would be very surprised if the intake, exhaust and Map gave you 10bhp! Let alone 20+...The M is pretty highly tuned in std form. Dubious.
 
ZM4000 said:
ok first things first i never claimed to be an tune expert. Thats why i asked in this forum. Thanks a lot for your answer mmm-five.
Click to expand...
Didn't mean it to sound like I was picking on you :oops:

I meant that that's what most peopel assume when they're told by the 'experts' at the tuning compan, and to take the claims with a bit of scepticism (and get a clear answer from the tuner before purchasing).
 
That's why i ask here on the forum first. Read a lot here on forums befor taking a decision for my exhaust and the intake.
With ECU's i dont have any experience here in Luxembourg we got some tunerdealers they also do software for the BMW Z4M but i'm not giving money away for a cheap product for a high quality car.
Heard a lot good things about ESS and really it is my favourite by now.
But havent decided yet i really wanna gain the maximum.
Aliv6 i really think u can take 20hp gain total with Exhaust,air kit and ECU. It should be realisitic. Of course if u want real hp gain u need a supercharger that changes everything :)
but the price....
maybe if i start a thread to have some donations it will help :P
I learned a lot about cars since i read more forums :)
I just wanted a real good looking car with a raw big engine thats why i bought the Z4m, didnt want a car with 2.0l motor and two turbos etc etc. if they open their hood and we open our hood :):):):) u know what i mean. :poke: :poke:
 
Evolve offer a remap and/or a carbon airbox with Alpha N tuning which gives a claimed almost 20bhp increase from the remap alone and a 30bhp increase for the latter. Have a look at this thread from M3torque for a bit more information.

http://www.m3torque.co.uk/showthread.php?t=405
 
dgm said:
Evolve offer a remap and/or a carbon airbox with Alpha N tuning which gives a claimed almost 20bhp increase from the remap alone and a 30bhp increase for the latter. Have a look at this thread from M3torque for a bit more information.

http://www.m3torque.co.uk/showthread.php?t=405
Click to expand...

Is it a software made by ALPHA N?? and it gives u +-20bhp? and with the carbon airbox -+30hp?
 
Alpha N is not a brand. It just means that the ECU has been tuned to operate without a Mass Air Flow sensor.
 
LOL man i dont hav eany idea about cars and tunes :)
I can write u tones about energy and atomic science but cars :D :driving:
no idea :)
Does anyone know something about evolve??
Are they good? Oh boy i really cant decide witch brand to choose to change my ECU
 
Is there nobody local that can just to a bespoke map for you. I'm getting a local guy to do mine...Costing me £350, instead of 1k!!!
 
Yeah there are but read on other forums that u need to go to someone specialized in BMW tuning. and the most known are ESS and RPI(powerchip). Now Evolve also....
I really want the brand that can maximise my wins and to each brand that i write the y claim to be the best :)
 
hummm...Disagree, BMW tuning is no diff to turing a Renault or a race car. imo.

Problem is, you can fake RR results V easily!!! For example a tuning company which i have experience of (Shall remain nameless) does a test of the std in std trim. It makes X. He them maps it, makes a tiny gain, which was predicted. Fiddles with the RR, or plays with tyre pressures, or runs it in a different gear and then all of a sudden it's making 10-15bhp increases.

............
 
OOH BOY
I dont know i'm gonna look here with a dealer what he can offer me. W'ell see. The prices are very high here in Luxembourg for ECU so i wouldnt benfit a lot doing it here the price are pretty much the same.
:cry:
10hp from an ECU remap isnt enough for me :)
On a GTI a friend of mine did have 210hp original and they put it up to 250hp wich is really nice. With a turbo it helps to gain more
 
lol. yes, Turbo gains cannot be used as a reference point. On a std n/a car ECU gains gains are extremely minimal, you're talking 5-10bhp MAX...My V6 didn't gain anything, other than a smoother power curve. (Thats actually more important)

In all honeslty, i'd save you're cash and allocate the cash elsewhere, say Brakes?!
 
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