Intake plenum and 911 throttle body - Page 16 - 986 Forum - The Community for Porsche Boxster & Cayman Owners

heymanwatchthis · 10-08-2016, 09:12 AM

I wonder how much impact this mod (plenum + 74mm TB) has using stock 986 airbox vs the 987 airbox?

eddy · 10-10-2016, 09:39 PM

Got the 987 box in. A little under 2 hours to get the 986 airbox out, probably 3 to get the 987 in-- fitting, then cutting, then re-fitting, then wishing that Porsche made bigger engine access panels, etc.

Cliff's notes:
trim as much as you can off the 987 box because it's a super tight fit.

I had to loosen the left manifold.

Lowering the engine saved a lot of aggravation.

---
figuring out how to mate the 986 MAF to the 987 box. Thinking that I am going to use a silicone pipe reducer where the 987 MAF clips to the box. Apart from the vacuum line i broke, that should be the last part i need to get this done.

Gelbster · 10-11-2016, 04:50 PM

Quote:

Originally Posted by heymanwatchthis

I wonder how much impact this mod (plenum + 74mm TB) has using stock 986 airbox vs the 987 airbox?

This is a good question because clearly the 987 air box is a huge pain and will deter some potential customers.

Ben006 · 10-11-2016, 05:01 PM

The problem with airboxes... is that, basically, the bigger the better! But also the more pain it is to fit...

I'm going to test a K&N panel filter tomorrow, and see if that makes a difference in the stock 986 airbox.

I believe the 987 airbox is a good mod to go along with the plenum, but not 100% necessary, I don't have one (but I have the headers and mid pipes).

I might give the 987 airbox a try if I'm not satisfied with the K&N. And maybe design something to make the modification of the box and the fitting easier!

I will contact a Porsche tuner soon that distribute GIAC tunes and have a dyno, see if we can work something out ! It won't be cheap though... We'll see, I'll keep you in touch!

Ben.

eddy · 10-11-2016, 05:41 PM

Quote:

Originally Posted by Gelbster

This is a good question because clearly the 987 air box is a huge pain and will deter some potential customers.

I agree. I thought about doing some testing with the 986 but ultimately decided that I wanted to just jump to the 987 box. I thought about other intakes but liked the fact that the 987 box is not open to the engine bay.

I'm sure it can be done more cleanly, but I had to bend the edge of the access area. I also elected to not cut the part of the body that buts up to where the box makes its turn, meaning that fitment isn't perfect. Just a bunch of little headaches that I'm fine with but wouldn't encourage others to dive into.

Progress update: box is in, plenum is in. Decided to get a silicone reducer to facilitate the MAF setup, so I've gotta wait till that comes in and then plumb the route to the TB.

Ben006 · 10-12-2016, 03:53 PM

Eddy!! We need pictures!!

I put the K&N in today too.
Just like the plenum, the first minutes felt weird, less sound, less power, but a very smooth power delivery.

When I got home (I installed it during lunch break...), it felt nicer, but still quieter than before!
We'll see how it does in a few days!

I took the time to inspect the plenum quickly, looks good after 6 months or so ? (I don't remember when I put it on ?).
I found a place where I can put a bit of reinforcement too. Don't worry testers, yours are totally fine! But if I can make it a bit better, I will

Ben

eddy · 10-12-2016, 05:38 PM

pics coming soon i promise!

mavis.d · 10-15-2016, 09:31 AM

So back from holiday and time to crack on with the upgrade. My plenum arrived the day went away which was a bit frustrating. I'm just waiting for the pipe and 90 degree bends to connect it all up. As my car is used 3/4 days a week I have decided not to swap to the 987 air box due to time constraints. Planning to do the work on Thursday (day off)
Looking forward to reporting back with some pics

Ben006 · 10-15-2016, 11:08 AM

If you don't use the 987 airbox, you should try the K&N drop in filter! I'm very impressed at the difference it made!

Ben006 · 10-16-2016, 02:22 PM

So, guys!

Today we met with ChrisZenithBlue for an autocross event, and since we have both 2.7L base models, we did a bit of comparison.

And I can confirm that my setup makes a difference! especially down low, the car just goes, and the power delivery is smoother!
I do run thicker oil than he does (15w50 vs 0w40)!

Now I really want to see the dyno results to put a figure on this difference!

And by the way, I would have never thought that a boxster would make such a good drift car ^^

eddy · 10-17-2016, 11:14 AM

finally got the silicone reducer i ordered. with luck, the car will be up and going sometime tonight.

jb92563 · 10-17-2016, 12:27 PM

Quote:

Originally Posted by Ben006

And by the way, I would have never thought that a boxster would make such a good drift car ^^

Haaa haaa, that explains all the knocked over cones? !

Ben006 · 10-17-2016, 03:45 PM

Quote:

Originally Posted by eddy

finally got the silicone reducer i ordered. with luck, the car will be up and going sometime tonight.

go go go

Quote:

Haaa haaa, that explains all the knocked over cones? !

I actually haven't knocked a single cone

madmodz · 10-17-2016, 06:45 PM

Heres some pics of my setup. I'm using a design-tek FAI. Its also sold as a agency intake and I'm sure other names.

I drove the car without an intake around the block and it drove good. I then did a plug change and tried to drive it today. The car will not idle past 2000 and I pulled these codes.

Only difference is a plug change, fai mounted. Got to research these codes. Anybody have any ideals?

Gelbster · 10-17-2016, 06:55 PM

Maybe you accidentally knocked off some electrical connections? If not ,note the codes, clear them and see if they return as Pending Codes after a few drives?

The Radium King · 10-17-2016, 07:24 PM

check your aftermarket intake - if wedged in there, it might be pressing on the wiring to an injector (#6 - closest to the back on the driver side) and causing an intermittent electrical connection.

Ben006 · 10-18-2016, 03:36 PM

If it happened after the plug change, recheck everything you did.

I hope it's not much!

I see that you used the piece of hose that I provided! how did it fit? Did the coil prevented it from collapsing? How did you get it straight on the AOS ?

madmodz · 10-18-2016, 09:26 PM

Quote:

Originally Posted by Ben006

If it happened after the plug change, recheck everything you did.

I hope it's not much!

I see that you used the piece of hose that I provided! how did it fit? Did the coil prevented it from collapsing? How did you get it straight on the AOS ?

I'm too burned out to work on her tonight. The aos hose was a little tight, but it fit with no issues. I did use the 15 degree 3" pipe that I cut down quite a bit. I also cut the elbow coming from the tb to give less of an angle. It turns to sharply in.

eddy · 10-18-2016, 09:53 PM

got mine in. cut the aos pipe just a touch because i couldnt get it unkinked. went for a drive and everything seems to be working great! it was wet out so i really couldn't push it. sounds great, though! i started a write up but it's time for bed. really excited that it came together! i'll be driving it for the next several days to let the ECU learn it.

Ben006 · 10-19-2016, 05:40 PM

If the AOS hose is too long you can always cut it, but I was more afraid of the other way round, because if it's too short... it's just too short ^^

The 3" pipes needs to be trimmed a bit to make it easier to fit, along with the elbow, like you did.
I mentioned it I think? I need to make a better first post like I just did for the shifters... but now, It's dinner time!