maf and throttle body diameter

[KRAM36]

Originally Posted by CraigM

Finally all in with 150 miles on it! Holy crap what a difference. Feels improved throughout entire range. Traction issues in 1st now, occasionally in 2nd even; 3rd and 4th pull HARD on the freeway compared to how they used to.
No real data on anything, sorry. Best I got for you other than butt dyno is this: there is a strip I always floor it along, doing 50 on the dot by the end of it very consistently before this rework. The 2 times I've done it since, I have been at 60 and 63, and that is feathering the traction issue through 1st, which was not an issue before.

***Thanks so much to everyone in this thread that figured all this out!***

Car is a 2000 2.7 5-speed.

Used a K&N filter (no codes), gold wrapped the airbox (no one will see it, and may keep the incoming air a little cooler, so I went for it), kept MAF where it was but added honeycomb, 996TB, 997 plenum.

Other performance mods are Circuit Werks secondary cat deletes, Baluga Racing exhaust, and TechnoPulley.

Yep, it's amazing. Feed this motor some more air and she lights up. My estimate is a 20HP increase on my car doing complete intake upgrade with a 987 air box.

987 v 986 Air box

[CraigM]

It's definitely a very noticeable change. Feels like a new car. And the extra pops and burbles on the overrun are always welcome!

I considered the 987 box, but ended up sticking with the original just because I have the 2.7. I don't think I need the big box. Maybe it would squeeze out a couple more hp for me, I don't know. But budgets are budgets, and I was maxed out for this project.

I will say, gold foiling the box was the loooongest part of this project. Had to unbolt the engine mount, lower engine and pull the driver's side intake manifold over to get it out and in in one piece. Not sure I would do that again. But after that, this was a breeze.

[KRAM36]

That is a nice looking wrap job you did. I bought some black VHT "Flame Proof" header paint and spayed the 987 box with it.

[stevessub]

[img]http://986forum.com/forums/uploads01/12071844_1052988844733144_694426548_n1443984092.jp g[/img

I want to install the larger TB also Can anyone tell me what I do with these pipes I cant find another boxster like it

[Deadeye]

To any of you who have been down this road, I finished up my install of a 987 air box into my track only boxster and it seems to be running a little rough since getting it all back together. Apx how long does it take the ECU to adjust to the increase in air flow? I can't run it on the street so I only have a few start ups in the shop so far.

For back ground, it has a '99 3.4 from a 996 and the ECU and the MAF are also from the 996

[jsceash]

Originally Posted by Deadeye

To any of you who have been down this road, I finished up my install of a 987 air box into my track only boxster and it seems to be running a little rough since getting it all back together. Apx how long does it take the ECU to adjust to the increase in air flow? I can't run it on the street so I only have a few start ups in the shop so far.

For back ground, it has a '99 3.4 from a 996 and the ECU and the MAF are also from the 996

It used to take about 15 miles. After having a 2004 SE flash with some other tweaks I can pull the battery and put it back in with no noticeable issues.

[Deadeye]

So I am at an impass. I took the car to a tuner and he put it on the dyno. As the rpms came up the air fuel ratio went to 16:1 and he shut it down. We called the shop that did the 3.4 conversion and were told that I should go back to the smaller 986 maf tube and smaller tube up to the 997 throttle body. I really don't want to go backwards but may have to.

Can the ecu be mapped to work with the larger intake? And who can do this?

[Wanderer]

I have an 08 Cayman S and am considering doing something like this as well. Are there any thoughts on what best approach to take for the M97 3.4?

If I can get any photos or measurements etc. from the Cayman to help anyone let me know.

[Gelbster]

For comparison and pricing purposes ,here is Pedro's Kit:
TechnoPower2 Kit - Increase HP output by 30 horses
He has an option w or w/o the FVD re-map of the ECU. That gives you an ida of how to budget any alternative remap from another source like ? ECU Doctors.
To get the full benefit of the mod ,there is the additional cost of also improving the exhaust system to eliminate some restrictiveness.

[rhinoman]

Originally Posted by KRAM36

Some pics of my modded 987 intake box using the 986 MAF housing.



I molded the 986 MAF house into the 987 MAF so I can clip it on and off.



Used Honeycomb Airflow Straightener so the MAF sensor gets a better reading.

This looks like a super neat job and is the step I cant get my head round for my conversion, any chance of a little more explanation on how you did this please.

[Lapister]

Basically, you need to cut the 987 Maf housing off just after where it buckles onto the 987 airbox. Then graft the 986 housing to the 987 buckle end. That's where you see the taper in the pic between the Maf opening and buckled end. Within that area you also plastic weld or glue in the new air straightner mesh since you will loose the original plastic one from cutting. It took me awhile to get my head around it. Having the buckled end really makes it a plus. This is a great mod with noticeable mid/top end grunt! The biggest PIA is getting the 987 box in. I had to bend the driver side front/rear tabs for fastening the engine cover.

[eddy]

Lapister, I was in the garage tonight trying to figure out the best way to do this same thing! how exactly did you graft it? I have picked up a few things, including some fiberglass, to try to make it as strong as possible but I'd love to hear how you did it and learn from your experience.

[Gelbster]

Related and of interest?
http://986forum.com/forums/general-discussions/31693-maf-throttle-body-diameter-post512648.html#post512648

[Lapister]

Eddy, I'm over 60 and it's been a year since this mod so I can't remember if I pushed one end into the other then grafted it with a plastic welder or if I just joined them end to end. The taper you see is from the welder. It works very well and quite stout too. HF has a cheap one. If you follow fellow Krams thread elsewhere on this forum he gives details. I pretty much applied his procedure. The toughest part of the mod is replacing the 986 airbox with a 987 box.

The more I thought about it yes I believe it slipped over then welded. But don't forget the air straightner/combmesh that has to get installed with hot glue gun also.

[djw8282]

Hello all,
I been follow this thread awhile and I just finished this upgrade.. Absolutely pulls harder. No question. My question to all is the hose that goes to the plenum to the AOS. Does it have to be perfectly snug on the plenum? No matter how much heat on the hose, I can't get it to snap in perfectly. Thanks!

[Lapister]

You will have to take the heat gun to it again and twist the hose a bit to get the correct angle to be accepted on both ends. It does take a little patience but can be done. You want them snug on both ends or you get unwanted unmetered air that could throw a code P1128/1130 and Cel. You know how I know?

[djw8282]

Thanks Lapister! Actually I stayed with it last night and eventually got it into position. Fits nice and snug now!