I will be dumping the "barn door" airflow sensor and going to manifold pressure metering. This means the stock air box will no longer fit. I am researching for Cold Air Intakes from various after market shops.

Anyone seen kits like these:

 

Or this:

 

Hey Pzull,

Is that K&N kit for a 964? Looks very sexy with that carbon fibre fresh air intake chamber!

Ciao,

Johannes E.

 

C4, looks like it but the mag where I found it is in japanese and didn't seem to have any order info. Checked K&N site and they didnt show the kit. Yes, Yes, they are sexy and I want one! Cant seem to find it on sale on the web

 

http://www.gruppemeurope.com/index1.html

i think this stuff is pretty similar....

 

Hi Christer,

Thanks Christer. Yes I found them over the weekend and emailed them to check if they have the same design as my pics. The designs avaialble on the GruppeM US site is quite different and inferior IMHO as they do not shield from engine bay heat.

They claim 15hp but I dont think it is possible but I'm looking at it only because I need an alternative intake system anyway because of the change in engine management system.

 

pzull,

After all that fancy exhaust work, I'm surprised you haven't hit the hardware store yet. I'm sure you can fashion one of these intakes on your own:


As you can see, it's a piece of bent, hard rubber. I think K&N sells a cone with the intake adapter (little plate which screws into place to accept the cone). All you need to do is add the bent (90-degree) tubing, add some clamps and you're good to go. The only tricky part is to make sure everything fits--seriously!

Avoid using a metallic tube as you'll want the intake to remain nonconductive, i.e. something that won't heat up. Also, the little L-shaped bracket is a good idea. You mount the bent end to your engine (you'll see some convenient bolts in the vicinity) and zip tie the straight end to the tubing. The extra support is necessary as your car bounces around.

Good luck! (BTW, this is my thousandth post, so let's make it count )

 

Joey, i am honoured indeed you chose to expend your 1,000th post answering my queries

No problem designing what you mentioned but I would use an Apex-i filter instead as it is a much better design for air flow as well as filtration (see pic)

However, I want to have a heat shield to insulate the intake air from engine bay heat. I might make one from ABS plastic (modified from large canister) if I cannot find the carbon/kevlar one which is also expensive as I just discovered (about $1k)

 

I'm wondering if it's even good since the cone is right in the engine therefore sucking in hot air.

 

How about the cone used by Shumacher and JPM? Geez, they even say F1 Power on them, so that's gotta' be worth a few more hp's.

 

I think the most important bit for me would be the heat shield not so much the actual filter. The former will allow my engine to breathe cool fresh air as opposed to pre-heated engine bay air. THe difference in the air temp stationary must be easily 10-20 degrees centigrade and when moving maybe 5-10 degrees difference.

Have done countless G-Tech (competition model) runs and hp/torque deteriorates after the 3rd consecutive run from heat soak. 60 mins rest with hood up, the power is back but only for `1st 2 runs.

 

Heat soak is a really comman issue with the 911 - (and the 356 for that matter) in fact porsche realized this back in 1963 - if you look at the 356 B Carrera GT. some of
these cars had carbs that were totally sealed from the engine compartment - the fresh air was directed in through the 6 louvers on the engine hood.
Something to think about is water sealing of the air intake - with the cone filter attached to the stock location the filter is out of the air stream and out of the water - if you move it out you need to have some sort of cover to protect it from water (not to mention hot air).
I don't believe that the filter will add much if any Hp. More induction noise yes, but it's just the entry point into the indtake system.
You are going to a MAF system i assume - what are you going to do to mate it to the DME and tune it? I thought about doing that - converting to a hot wire system like the 993 but was stumped as to how to optimize it for the DME without resorting to a different engine management system (MoTeC or TAG)
Sounds like a fun project though. I used a Simple K&N system in my car and was happy with it - light and cheap.

 

Rob,

After exploring the options, I've decided to go with a full change of engine management called Autronic. I think it was founded by some of the original Motec engineers so its very similar in design and a fraction of the price.

I will be using absolute manifold pressure for metering with secondary metering using throttle position. This way no airway obstruction and no hot wire to get contaminated and give wrong readings and its fully tunable so it can be optimised for future mods if any (I've decided this would be my last mod, but you never know)

After searching for a long time and couldn't find a suitable intake system off the shelf, I was designing one myself but had problems finding a fabricator. But got lucky and came across the GruppeM EUro version intake (I dont think the US versions are too great in design). Its expensive but I calculated the amount of grief and time associated with fabricating my own and have 96.4% decided that I will order it within this week.

 

I like it

I also love your avatar. It always reminds me how good our cars look.

Please keep us posted on this mod (if you decide to do it). I'll be interested in how it works out for you.

 

If you are considering a Maf conversion but need to fine tune the mixture you might look at the PSC1 made by split Second
http://www.splitsec.com
I just used the PSC1-003 on my 944 turbo and it worked great and at $235.00 is very affordable.

john