MOD SHACK MOD: MAF screen expose......10%+.....(UPDATED)
07-28-2002, 01:40 PM
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Re: MOD SHACK MOD: MAF screen expose......10%+.....(UPDATED)
You reached the highest g/s that the MAF can measure without the screens. When you reduce more restrictions before the MAF you will not see more g/s, that's what I've learned. I worked on my air box again and will post the results tomorrow. I've measured 213,23g/s before but only 200 when I removed the screens. Also boost was reduced from 1350mbar to 1300mbar. Take a look at the injection times. They will go down too without the screens. You will run lean. I will post the new results tomorrow.
07-28-2002, 01:49 PM
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Interesting but....>>
I don't know what caused you to see less flow with the screens removed. My airbox is an lltek, normally sealed and insulated with a cool air feed but running open for these tests. No improvements I can make on that end. As to running lean, my A/F gauge indicates no issues or problems, but I'm running an APR chip, probably programmed to run a little rich on heavy boost. Hit my link below to see these mods.
07-28-2002, 06:42 PM
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Steve, had been reading about the straightner...might have some negative side effects if removed
there have been incidences on several VW and Audis the removed the screen and began throwing fault codes - lean / rich codes. It seems that the extra turbulence across the MAF may have been the cause. Don't recall if they only had stock air boxes, though.
Since we are running the cone filters, which are supposed to redirect and smooth out the airflow, it might be less of an issue with the screen.
It's be great to get more flow! I'm pretty much at max boost of the turbo, I'm running it at 98% (according to Hans), and have about 230 g/s max flow. Don't know if I can get more flow! I'm not even running lean...as a matter of fact, think I run rich (per my muffler guy).
Since we are running the cone filters, which are supposed to redirect and smooth out the airflow, it might be less of an issue with the screen.
It's be great to get more flow! I'm pretty much at max boost of the turbo, I'm running it at 98% (according to Hans), and have about 230 g/s max flow. Don't know if I can get more flow! I'm not even running lean...as a matter of fact, think I run rich (per my muffler guy).
07-28-2002, 06:51 PM
#18
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I'm thinking the same thing on the cone filter....>>
Suspect much less turbulence at the MAF intake because of it. A/F gauge seems to be reporting same readins as before with no leanness showing up once it gets out of closed loop operation. You noticed higher G/sec readings with the VW MAF element, correct? BTW, highest G/sec on Marcus's stage 3 was 207, but bigger MAF housing....
07-28-2002, 07:24 PM
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yeah, got higher readings with the VW MAF...interesting that Marcus is only getting
207 with the bigger MAF housing. John S reported readings at about 204 g/s with the stock. I'm definitely getting higher MAF readings with the porting of the intake manifold. My friend also got about 223 g/s max with the same setup. I'll be getting some readings from Bob's car - we have the same intake and manifold, BUT he's got stock ICs and APR.
With all the discussion around airflow and MAF housing size, I'm wondering if Marcus' lower airmass readings are the result of the stock air box?
With all the discussion around airflow and MAF housing size, I'm wondering if Marcus' lower airmass readings are the result of the stock air box?
07-28-2002, 07:32 PM
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My peak reading was 207 also......>>>
On Marcus's setup, his manifold pressures were not all that different from mine. Comes on later and holds longer though. Bigger MAF, with same G/Sec reading is still flowing more air. We suspect the stock box is probably a restriction after staring at the numbers for awhile. I'll try to source that other MAF element tomorrow. Looking forward to seeing some numbers off Bob's car.