legacycentral bbs

I heard that the MAF freaks out above what? 15lbs boost?

So if I were to go higher than that what would I need to do?

(All supporting mods done of course)

Just swap in a Liberty MAF? Or does someone make an aftermarket one that can go higher?

If you're doing the supporting mods, then you've got an engine management system appropriate for your power, so just use whatever sensor(s) that system's designed for.

Exhaust, 440cc injectors, TMIC, Fuel Pump, FPR

...and ECU, right?

Well, I was going to do that afterwards...

Gotta do it first. The MAF sensor works with the ECU.

I thought it was possible to use a different one?

No?

Okay... Can I use a perfect power?

Well, anything can be done... douglas vincent has done some ridiculous things with manipulating MAF sensors and fuel delivery, but that's all a little more ghetteaux than I could ever recommend.

Think about it -- the injectors, MAF sensors, and ECU have to all work together, right? The ECU reads the amount of air with the MAF sensor and then pulses the injectors to put in an appropriate amount of fuel. The ECU has a table in it that translates MAF voltages to airflows, and it knows how much the injectors flow.

Moreover, a MAF sensor has a quadratic transfer function. So quadrupling the airflow will actually only about double the signal. That means you can't just match up bigger injectors with a bigger MAF sensor and get reasonable fueling.

Moreover, tricking the ECU on the input side and the output side has another issue - the ECU's also in charge of spark. And at low airflows the spark can happen a lot earlier than at high airflows. If you mess with the signal you can end up with way too much spark advance.

I think people have used the Perfect Power. Didn't Josh write a lot about it?

Yeah, the PP6 is the direction I'll be heading when I get the free cash & my TurboXS Dtec will go to the wife's '98 LGT (can't say much more than that at the moment, it's hush hush). The PP6 offers more range to tweak on different settings for proper tuning options (which will be tackled by professionals who have an AWD dyno).

Here ya go: (read up on it)
http://www.perfectpower.com/products/smt6.asp

I'm probably planning to use the Z32 MAF
http://www.ecutune.com/svx_stage_2_parts.htm

I've been talking with the guy at ECU tune. Talked with him today, and will probably wait for him to work on the turbo ECU.

Vikash, did you get the email I sent you on your gmail account?

Oh, yeah, thanks for reminding me, Josh. I did get it but haven't gotten around to going through it and writing you back. Sorry about that -- I'll look at it.

smh0101 wrote:I heard that the MAF freaks out above what? 15lbs boost?

So if I were to go higher than that what would I need to do?

(All supporting mods done of course)

Just swap in a Liberty MAF? Or does someone make an aftermarket one that can go higher?

i want to ride in your car this summer @ WCSS or subiefest.
you're doing crazy stuff

Are you going to drive out to the west coast to come to WCSS or Subiefest?

as long as it's in august.

i got school and internships til then

Cool... West Coast Subaru Show is in August... its all the way in Astoria, OR (a coastal town)

Hope to see ya there!

Back to MAFs now

smh0101 wrote:I heard that the MAF freaks out above what? 15lbs boost?

So if I were to go higher than that what would I need to do?

(All supporting mods done of course)

Just swap in a Liberty MAF? Or does someone make an aftermarket one that can go higher?

For one...Liberty MAFs are the same as the JECS plastic one.

As Vikash pointed out, running a larger MAF like the JECS may get you a slight amount of range, but really won't help you much. You need to modify your ECU first.

Honestly, you can make a ton of power at 14 psi with a VF12 or whatever you decide to use. More than you honestly probably need at this stage of your driving skill. Then, if you decide you need more, you will need to look at doing some piggybacking or standaloning.

Thanks Nick...

I wasnt really planning on going over that... just doing research.

And hopefully the vf-12 will be on its way in a week or two.

I wont put it in for awhile... I have more things to do first, but I'll have it for when I do.

And I'm working on the driving skill.

smh0101 wrote:
And hopefully the vf-12 will be on its way in a week or two.

Where did you find one?

A member who bought an RS-RA motor but is using a different turbo.

Hmmm......only 3 of those guys around.......

Hmmm...

Dont even try it! lol

Well, 3 guys, 2 engines. I'd have to look at really old posts on Nasioc, but possibly only 1 turbo.

I never said it was on legacycentral.

And they werent only on RS-RAs

Don't worry, no plans to snipe a turbo. Just playing your cat and mouse because I'm otherwise bored.

Now, if I didn't have 2 sets on the shelf, I might try and snipe your fogs!