no tune boost

[wise67]

what is a safe amount of boost to run with no tune? Still saving up for some dynotime

[RAiMA]

I wouldn't. The car would just run lean and detonate. The timing would also be way off.

If you don't have the time to do it right, you don't have the time (or the money) to do it wrong.

Just be patient until you can do it properly.

[wise67]

From what I understand you can run the DA with no tune, what would be different than running a turbo setup and 4-5psi?

[onewhippedpuppy]

The DASC features a rising rate fuel pressure regulator to increase fuel pressure with boost. This is essentially the "tune", as it is a mechanical means of doing the same thing as the DME.

[denglish318ti]

I dunno, but I am running 11psi on stock internals with the DASC now, probably a bit too much really.

[denglish318ti]

Hit 12psi today, water injection added 2psi boost!

[BMW_Hatchback]

I've heard 8 or less, (which goes with the DA comment I guess)

[xxxJohnBoyxxx]

^^^8psi is all I would do with a RRFPR. Anything more and your asking for trouble. My opinion is the 19# injectors will pin at very high fuel pressures and you will also kill your fuel pump.

Now I have heard of 1 or 2 people doing 15psi on a stock tune but count me out on that, I like my motor without the big window in the side.

1 second or two without fuel and it's all over quick, sounds like a garbage disposal with forks in it as you motor self destructs

[bmwconnect]

IMHO a RRFPR is the worst way to introduce fuel for boost...1. our old fuel lines burst and can easily catch fire 2. the fuel pump has a pressure realse pin set to 100psi witch will bleed off the pressure witch intern causes pulsing in your fuel line with will put you from rich to lean quickly with almost no time to react to save the motor... boggles my mind to this day that such a setup would have ever used such a crude method to introduce fuel

[denglish318ti]

The max pressure the rrfpr that comes with the DASC goes to is 85psi, I couldn't get it to go any more. It is a rubbish way to do things, but a custom tune can introduce massive costs. It is quite a lot of fuel pressure to be running and I am not totally comfortable with it!

A question, I was running 10 psi with the 3.4psi pulley. I then put water injection on and it jumped to 12psi. Where does this extra boost come from, and is it too much boost?

[xxxJohnBoyxxx]

Originally Posted by denglish318ti

The max pressure the rrfpr that comes with the DASC goes to is 85psi, I couldn't get it to go any more. It is a rubbish way to do things, but a custom tune can introduce massive costs. It is quite a lot of fuel pressure to be running and I am not totally comfortable with it!

A question, I was running 10 psi with the 3.4psi pulley. I then put water injection on and it jumped to 12psi. Where does this extra boost come from, and is it too much boost?

The extra boost comes from the water sealing the rotors in the supercharger. Is it too much boost is up too you, it is your car and it is your wallet so if it breaks it will be your fault.

The water injection helps to lower the detonation point and make a safer running motor at higher boost. It is used as a bandaid for a bad tune in a lot of setups like when running a RRFPR. If you are happy with how the motor runs then that is what matters isn't it? If you are worried about blowing it up then remove the pulley. My opinion and it's only a opinion is leave the 3.4" and run the water injection since it is working good for you.

If you want complete security and a great running car pay for a tune and larger injectors and be confident that you have the best setup possible. Even cars on excellent setups blow the motors from abuse so nothing is 100% you will not blow it up. If you are happy I've seen lots of people running 3.4" pulley's with no issues at all. Water injection really helps to add another safe-gaurd to the system to help cool down everything and control detonation.

Good Luck, John Smith

[denglish318ti]

Cheers John, a good read. I want to get the technique tuning tune, but as I am in the UK it is a bit of an effort as my car will be off the road for quite a while. If I get a custom map in the UK on a rolling road I am looking at about £500. I will see how it goes, M44 engines are cheap anyway!

[bmwconnect]

Originally Posted by denglish318ti

Cheers John, a good read. I want to get the technique tuning tune, but as I am in the UK it is a bit of an effort as my car will be off the road for quite a while. If I get a custom map in the UK on a rolling road I am looking at about £500. I will see how it goes, M44 engines are cheap anyway!

I can author you a tune for 320canadian

[denglish318ti]

That is sweet, but I don't get how it works? So I would tell you my spec:

DASC
3.4" pulley
water injection with the smallest aquamist nozzle coming in at 5psi boost
Possibly upgrade to a bigger MAF off a 328
Max boost 11 psi with water

And then you write the tune, I pay, you email it to me, and then what happens?

And what is the feedback loop in terms of improvements?

Sounds like a good option, would like to know more!

[denglish318ti]

Oh yeah, and I would need to get the injector adapters (maybe from Metric Mechanics) so I can upgrade to larger injectors, and I guess you would advise which ones to use?