SLP LS1

Now if I buy polished MAF ends of plastic MAF ends it is going to mess with my stock tune right? I'm going in for a tune shortly after doing headers so it won't really hurt anything if I end up going with polished or plastic MAF ends right? Because I'm gonna get a tune anyways...?

SLP LS1

WILWAXU

iTrader: (6)

I ran ported MAF ends on my car when it was stock internals with great success.

Once you step to H/C, most tuners like to stick with stock MAF ends for easy of tuning.

mrr23

iTrader: (3)

i have the vinci polymer ported MAF ends on the wife's car. had it on since the beginning. even tuned with it. here' the dyno i did with it.

Rhino74

iTrader: (1)

Was the before and after dyno run done without tuning inbetween, or was there some fiddling around after bolting on the ported MAF ends?

If this represents simple bolt on power gains, this graph would tend to clear up a lot of confusion as to the merit/ dissaster of installing ported MAF ends.

Thanks!

Ryan

mrr23

iTrader: (3)

it was a back to back dyno run. no tuning was done.
dyno 8 before
dyno 9 after

Rhino74

iTrader: (1)

Did they run an air/fuel mixture along with the dyno pulls? I wonder if the power was caused by a slight leaning out effect, which may not have lasted once the PCM readjusted, as it does with some other mods.

TAQuickness

iTrader: (28)

Search "MAF" titles only. The gains from molesting your MAF are hit or miss and generally not worth the effort.

Doski

I have mafends and my car runs just fine! But i have a maft to richen it up a little......

mrr23

iTrader: (3)

click the pink banner. you'll see every dyno i have made when testing products for vinci. the gain from the MAF ends never went away. the o2 readings before the MAF ends were 950ish. after the MAF, they were 890-910.

Rhino74

iTrader: (1)

mrr23, do you know what o2 readings correspond with a Stoich A/F ratio of 14.7:1?

I googled "O2 sensors" and "Stoich", and found one guy who wrote that .82-.86 is about right, with anything over .86 starting to run a bit rich. I'm not sure if that's a car specific number though.

TAQuickness

iTrader: (28)

take a look in the tuning section for LOTS of info on NBO2 voltages. You really need a wideband to make any accurate measurements of AFR

mrr23

iTrader: (3)

890-910 = about 13.0:1. i have other dynos showing the a/f ratio and they were 13.0:1.

Rhino74

iTrader: (1)

My car doesn't smell as rich at idle with the new MAF ends. Its still rich but it used to gag you just make your eyes water when you walked by. I think the leaning out effect has worked out well. There's a little better thorttle response at part and full throttle as well, probably from a better air/fuel mixture. No issues that I can tell at WOT either. No audible pinging or knocking, so far, everything seems good.

Fast Toys Performance Parts

iTrader: (3)

As mentioned, MAF ends can be hit or miss. The cases where they do make power are on vehicles that are running a little rich to begin with. Their net effect is to lean out the mixture as some air comes in unmetered. The 98-99 cars seem to run rich from the factory and can pick up to 1 MPH in the quarter mile. Proper tuning should be done with a wide band.

We sell the composite plastic MAF ends which also have the advantage of not heat soaking.