Intake/Injector idea

[kadinga]

If I were to hack the maf wide open (still keeping a clean channel leading to the sensors) could I compensate for the leaner mixture + possible timing retardation by replacing my stock 450s with 550s (because the signal would open them for the same amount of time, right) and slightly advancing my timing? I am looking to do every possible cost effective mod that doesn't require a full tune.
The Theory:
ported maf = less air mass detected = less fuel delivered = leaner mix = higher 02 detected = less advance
So wouldn't a bigger injector compensate for this by operating on the same pulsetime but allow more fuel in hence:
bigger injector = more fuel
more fuel + more air = bigger boom = more power
correct ratio = correct 02 readings = correct timing adance
The Problem:
getting the ratio right (fixable with safc), unforseen issues

My dsm is in the shop right now getting all her boost, intercooler leaks, alignment and other issues resolved. But did I do my math right?

cheers

ps. full copyright if it works

 

[kenamond]

Or you could run a 2g MAS (less airflow reported), 550s (gets you pretty close to matching the 2g MAS airflow difference), and AFC to get it dialed in. So you'd trade off time hacking the 1g MAF for buying a used 2g MAS. That's my recollection on that mix of mods, so you might want to search a bit rather than trust an old fart's memory.

I've read "hacked MAF" a trillion times on this forum but don't know much about the "art" but it sounds too error-prone to me. The honeycomb gives a very predictable airflow, and I don't know how a "bad hacked MAF" might react as airflow increases.

So I can't say it's a dumb idea, but I'd be nervous doing it.

 

[rarson]

A wide open MAF without any honeycombs isn't going to register airflow correctly at all. The MAF is a Karman-vortex sensor... it relies on the honeycombs to straighten the air out in order to provide accurate readings.

That said, the 2g MAF already flows more than the 1g. Why would you try to hack up the 1g when you could just do what kenamond suggested? The car will probably run better and you'd also likely get just as much airflow. IMO, there's really not much gains to be had from hacking the MAF for the tradeoff in driveability/idle problems that you'll get. I hacked my 2g MAF, and while it seemed to work, now down the road when I'm running a larger turbo I just wish I had a straight set of side honecombs and something to put back in the bottom. It's not worth it. You want more airflow through the MAF? Get a bigger turbo.

Edit: I want to stress that I had idle and driveability issues with hacking the MAF. It definitely wasn't all sunshine and roses. Considering that I can't really say there was a solid performance improvement, I really think it's not worth it. Hacking the MAF is really just an old way to lean the car out a bit, back before we had all the great toys that are available today.

 

[kenamond]

A wide open MAF without any honeycombs isn't going to register airflow correctly at all. The MAF is a Karman-vortex sensor... it relies on the honeycombs to straighten the air out in order to provide accurate readings.

That said, the 2g MAF already flows more than the 1g. Why would you try to hack up the 1g when you could just do what kenamond suggested? The car will probably run better and you'd also likely get just as much airflow. IMO, there's really not much gains to be had from hacking the MAF for the tradeoff in driveability/idle problems that you'll get. I hacked my 2g MAF, and while it seemed to work, now down the road when I'm running a larger turbo I just wish I had a straight set of side honecombs and something to put back in the bottom. It's not worth it. You want more airflow through the MAF? Get a bigger turbo.

I think he's trying to get more aggressive timing by running off of a lower-load portion of the timing map.

 

[rarson]

He'd still get that with a 2g MAF, injectors, and AFC to lean it out.

 

[kadinga]

thx the quick responses! To be honest, I already ported it because, well, its really cold right now so the leaner, hotter mix wouldn't hurt and I need to replace it anyways. I'll def look into a 2g maf, 500-550s and afc. My real goal is to increase performance AND efficiency of the engine. IMO, if you want to go fast, I mean REALLY fast, without having to hit every 2nd gas station, just turbo a gixxer. Not that I don't enjoy my dsm

 

[kadinga]

I think he's trying to get more aggressive timing by running off of a lower-load portion of the timing map.

ya, the timing would be nice. I aim to get a bigger bang with the same amount of fuel.

 

[kenamond]

He'd still get that with a 2g MAF, injectors, and AFC to lean it out.

Sorry, I wasn't too clear. I was responding to, "You want more airflow through the MAF? Get a bigger turbo."

 

[kadinga]

Hmm, what if I converted to a gm mas and threw in 550cc injectors? The thing is, I'm trying to keep repair/mod costs down, emissions down, economy up and power up. There are sooo many scrap yards around here where I could find a decent mas. I know those may seem to conflict but I'm pretty sure if I allowed more air in and it actually registered correctly the engine would run more efficiently, powerfully and possibly even lower my boost threshold too. Any other takes on this? I'd like to have my ecu chipped or socketed and maybe even run a dsmlink or moates device on it, but that won't be for a while.