To Port or not To Port

**linthead** · 07-17-2007, 07:30 AM

recently, i was skimming through an old Pontiac magazine (My other car is a '72 LeMans Sport) and in an article about LS1 improvements was a warning to not be tempted to modify the mass air flow housing since it could lead to problems with the engine management system. It seems to be a very popular "free" mod so I was wondering about this before I do it.
Any help will be appreciated.
I

LOVE my 99Z M6!

**Anthracis** · 07-17-2007, 11:32 AM

MAF can be quite sensitive. I've read that you can swap it out for a larger corvette Z06 unit. But I'm unsure of the performance gains from this swap. I will be upgrading my 75 mm throttle body to a larger 80 mm LQ4 throttle body from a truck. Hopefully some gains can be had from that swap.

**aerojt** · 07-17-2007, 08:20 PM

I am interested in putting the z06 maf in mine too, anybody have info on that swap? Thanks

**SSTODD** · 07-18-2007, 07:41 AM

I vote for leaving it alone, I kept throwing lean codes with my SLP 85mm maf and most cause the same issues. unless you plan on having the car dyno tuned to get the maf calibrated to your car it is a waste for very little gain.

**Hot Rod SS** · 08-01-2007, 01:57 AM

De-screen it and leave it alone.

**jad628** · 08-01-2007, 03:42 AM

Originally Posted by Hot Rod SS

De-screen it and leave it alone.

x2. You're better off porting and polishing the TB and keeping the MAF stock.

A realistic estimate for the MAF would be 2-3 rwhp gain, which is okay, but not at the expense of throwing a bunch of codes and having headaches associated with the ECM. You can get the same gain from porting the TB, and not have to worry about electronic issues.

**kyemt** · 08-01-2007, 04:54 AM

i say port and polish both and descreen the maf, hell u cant ever have enough power, i too kept getting lean codes with my slp 85mm maf i upgraded to an 85mm tb and no codes since

**ICRAZY6** · 08-01-2007, 05:09 AM

I've done both. I'm currently running the SLP maf. If your running a stock LS1 manifold or LS6manifold porting the maf is not going to help you and chances are while tearing it apart you could end of damaging it. Now if your going to be putting a 90/90 set up on I would sudjest that you go with a larger maf, Slp or ZO6, because the maf would bottle-neck the air coming in.
If your wanting to put the SLP on a stock LS1/LS6 you will run slightly leaner, that's because there's more air entering the manifold and the SLP is made to read like it's stock from the little resistor on the wires inside. The ZO6 maf will require you to have a tuner pull the stock maf table out and up load a ZO6 maf table for it to operate correctly.
In my case with running a 90/90 set up I chose to use the SLP unit. I could have also went and purchase a maf translator from Predator and that would have opened up the maf table as well. Hope this helps you out.