Larger (custum) throttle body on 996 3,4L (wire gas)?

Has anyone made a larger (custum) throttle body on their 996 3,4 (wire gas)? Please tell more if so... Original larger throttle bodys (GT3 82 mm) is as I can see only availible for E-gas. So how to upgrade the full plenum on wire gas...

MaxBore will do it as they did my 3.4 eGas one. George has been in business forever and that's all they do. I've had him do close to a dozen over the years. You're probably looking at 2-3mm increase on the avg.

I think the original is 74,6mm I want to go all the way to 82 mm. So im thinking of making it al custum if its possible, maybe using a e-gas housing and rebuilding it with wire gas modified parts. I dont know if it is possible. Then I could use the IDP from e-gas 82 mm. What are the features on the throttle body besides from the valve inside? I can see from the pics that wire throttle body has a hole inside on the wall, I cant se the same on the E-gas one. What is this hole for? Where does it lead? Can anyone tell med how the throttle body works and if it would me possible to modfy a fusion like the one i mentiond?

What's the point to go that big? Do you subscribe to the bigger the better theory? Look at all the manometer tests out there if you wanna be enlightened. Or else spend the money and effort for only negligible increases.

"I don't know how it works, but I know I want a bigger one." -Everyone. Always.

FVD makes a 1.8 overbore on the cable 3.4 TB. I honed out the plenum to match and along with headers it made about 8-10 more rwhp on a Dynojet. Max bore will also hone out your plenum for a small fee. I have a couple of stock 3.4 cable TB's sitting around here somewhere if anyone wants to buy to play with.... I know of another Rennlister who made a cup car TB work on a 99' cable TB car that's currently sitting in my wrench's shop. I have no idea how he did it but I'll forward this thread to him and see if he'll chime in....

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If you want to put on a larger cable TB why stop at 82mm? http://www.ebay.com/bhp/ls1-92mm-throttle-body What's the goal here- more hp I'd wager. If so, a larger TB is only part of the equation. Forgive me if this is a bit remedial. More fuel + more air + larger displacement+ more efficient exhaust removal = more hp Here's how we got 322 whp (NASA Dynojet) but as always, YMMV. Step 1. Get your cheque book out. Step 2. Increase TB bore Step 3. More efficient air intake Step 4. Increase displacement to 3.6 (long stroke/same bore) Step 5. X51 plenum Step 6. X51 headers (no cats with custom exhaust) Step 7. Custom map on dyno I think we went from 284 to 322 but that's not a back-to-back scientific comparison. Basically you can't cheat the laws of physics and a '99 996 is inherently hard to find extra hp. The Motronic DME is relatively primitive and is diffiult to hack (had to use a piggyback to control the extra fuel and airflow). It was a process.

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Cup car TB is also cable by default so it wouldn't be all that difficult. OP is talking about a 3.4. Like I said show me pressure differential on a manometer to justify anything more than a couple mm increase to show any differences. If you don't know how to use or have one, at least measure the MAF readings on a scanner and show me a big difference on the readings between using 2mm increase vs the gt3 sized TB on a 3.4.

The TB bore was the cheapest part of the exercise- like $100. I did to make sure mine was operating as it should (basically they rebuild with new butterfly, screws etc.) but I'm under no illusions that it did not contribute much in the scheme of things. An option is also to put on a non-Porsche cable TB. They are not nearly as expensive. Also considered Schrick cams from Germany, but in the end what we did made more hp than the class allowed and we had to dial it back to 310 I think. The power's out there, but its not cheap (vs. BMW M3 or Corvette) and it there are no "packages" except to mimic what Porsche itself offered (X51- and that was a pretty hefty option from the factory). Did I leave anything out JRG or OFV??

I dont mind getting arrested for this. Just throwing ideas out there. But the E-gas version of the 3,4 can do the 82 mm upgrade all the way on the intake. Many other models to like the boxter etc. People report that it has effect. Im now totaly rebuilding the engine and putting on full sport echaust + doing a flash of the ECU from Vivid racing. I only thougnt I could gain some litte more by upgrading the plenum to 82 mm, like they can on the e-gas version of the 3,4. Thats one of the things, the other is that i like Mac Gyver stuff, so I also like the challange of making a good and well working custum part.

Blame IPD and all their marketing tactics for even thinking of going with 82mm on a 3.4. Before that I'm sure not too many were even thinking of this option and the ones that did knew it didn't make too much sense. Now I can see if you went with upgraded cams and massaged head where it could make a difference in the upper rpm bands but without those, I'm bench dyno guessing only 1-3hp difference from a 2-3mm port in the upper bands. If you wanna pull a macgyver, the cable tb is definitely feasible as you would only need to fashion a tb adapter plate and cable bracket and make sure the tps values stay consistent with stock or transfer over 996 tps and clock it accordingly. I'm not here to deter you in anyway but rather try to steer you away from either mistakes I've made or ones that I know have minimal or very negligible returns. Like a typical dummy I've spent way too much on frivolous mods in the past.