34 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH74 -> 78mm Modified TB
Leading reported evidence
Install on my 4
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I have the kit ready to be installed on my 4.1L build.
Leading evidence: 'Install on my 4' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check after everything’s in and save time, brain cells' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I use a Soler for now and it works well with my tune, air box, header, cat upgrades.
Check after everything’s in and save time, brain cells
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Smoke check after everything’s in and save time, brain cells.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
There's a company on eBay offering a "modified" 74mm TB for our cars that claims it has the effect of a 78mm TB, without having to change anything else.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
There's a company on eBay offering a "modified" 74mm TB for our cars that claims it has the effect of a 78mm TB, without having to change anything else.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
34 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261027T082735Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
There's a company on eBay offering a "modified" 74mm TB for our cars that claims it has the effect of a 78mm TB, without having to change anything else. Anyone else seen it? Any thoughts? Was just exploring alternatives to the 82mm since it doesn't appear to be beneficial on the stock 3.4/3.6 motors.
Link
This would only be effective with mods to support the change in chorus. You'd need a performance air filter, new plenum, larger or ported intakes, headers, and an exhaust to make use of it. I don't see the harm in trying personally. Just work towards adding the other mods sequentially and you might see 10-15hp gains on a 3.4. Maybe.
For a 3.4:
Air Filter
https://flat6motorsports.com/product...er-996-carrera
FVD throttle body mod
https://www.fvd.net/us-en/220110905A...e-send-in.html
IPD Plenum
https://www.fvd.net/us-en/2201109960...-throttle.html
Headers
https://flat6motorsports.com/product..._organic&gQT=2
Or an LSX 😅
I was just curious, since the price is significantly cheaper than the 82mm from FVD, and then there�s an IPD �clone� on eBay for ~$200. Even if the result was better throttle response and some sound, it may be worth it if the 82mm loses low end on a mostly stock car.
If you want improved throttle response, you will have to get a reputable software package. But you will get improvement with the intake sound using the IPB/TB combo. But keep in the back of your mind that the IPD/TB combo will move your power delivery up the rev range a bit. So you may give up some mid range power.
I'm in the market for a banged up GT3 project eventually but chasing power is fun. I was thinking about the softronic tune and 200 CEL Cats for my car at some point.
These two mods will give you the biggest bang for your money. Software will improve throttle response and 200 cell cats will improve power. $3k will get you 10-15 additional HP/TQ.
For sure, upgrading your suspension, brakes & tires will allow you to carry more speed. I highly suggest it. But it will cost you $8-10k for the suspension, $3k+ for brakes, and $1.5 k for a good set of tires.
I would give Rhonda at FVD a call and talk to her about their software and 200 cell FVD/M&M cats. Also talk to her about whats needed to be done to be able to get some power out of the IPD/GT3 TB combo. She will tell you about the their FVD/M&M equal length long tube headers that are properly ported by M&M that will help with flow. But that's another $2k.
You can see with my signature below some of the major enhancements i have done to my 996 over the past 22 years. The 996 is a very FAST car if you set it up properly and you know how to drive on the track and street. To put it another way, in stock form, it has more power than the vast majority can safely handle on the street.
Fwiw, I have driven everything from the 944, 964, 993, 996, 997, 991, 992, 986, 987, 981, 718 on the track over the past 20 years, and i still own my 996 to drive on the street and track, and haven't switched to another model.
The reason is that a well sorted 996 is a pure joy to drive on the street and track, even though it only has 320 HP.
Soler does throttle body porting. They have good info on their website. As others mention, this is good for mild upgrades like tune, 200 cell, headers, filter, etc. I use a Soler for now and it works well with my tune, air box, header, cat upgrades.
For sure, its a relatively inexpensive part. I was going to buy it and test it against the GT3 TB. Who knows. It may provide a benefit. I got a few more items to do on my 996 and then can get to it to test.
OP - Whatever you try, do things in stages and try to data log. Butt dyno’s aren’t well calibrated.
Next week, I’m switching over to GT3 tb and trying out the plenum Brandon says works according to his dyno pulls. I‘ll get a dyno done and see what’s what.
Here is an interesting thread from a few years ago that delves into many air intake topics plus many more.
https://rennlist.com/forums/996-foru...rbox-dyno.html
Can you post or send me a link via PM? I think I probably have the right one saved to my watchlist already, but want to be sure. Is it different internally than the IPD?
I have the kit ready to be installed on my 4.1L build. They're all fairly similar but I would just ensure that you buy the one for the GT3 throttle body. I believe Brandon mentioned something along the lines of the IPD one having the wedge inside which disrupts the air pulses. The build and casting of the plenum is very nice.
Looks good. The original IPD plenum was smooth inside. Then they went with the golf ball dimples because they said it was a better design. I don't remember which one I have. Looking forward to hear your impressions.
But the IPD is wedged inside, like two pieces of curved pipe welded together. Not as "straight through" as the one Pete posted above. Curious which is better?
Someday, someone will take the time and money to test all of them on a dyno to see. It looks like Slakker has been doing some of this. It also looked like Jake was doing it as well in combination with developing new products or configurations. But I haven't seen any comprehensive data analysis that pulls it all together to eliminate the fog.
But that's very common for bolt on HP/TQ. Fingers crossed we get a definitive application and answer.
Hah!
Part of the fun of owning a 996 is testing out stuff to see if it works. You can always go back to stock and sell what you don't like or don't need.
Does anyone have a source for the rubber hose from the air filter box to 82mm TB? I want to get the plenum from eBay and the TB from a parts house rather than buy the overpriced IPD kit that doesn�t flow. All I need is the hose.
You can find them on-line. Just make sure you search for the 82mm TB type. I had to order mine from a shop in UK since my car has the X51 intake manifold and the hose has an extra side port that needs to be connected.
Check Spyder Performance.
Parts update: The eBay plenum, OE GT3 throttle body, Spyder silicone all fit together. Should all be installed end of next week, time allowing.
Don’t break any little vacuum hoses and everything goes in as expected…tight space and lots of hidden sources of post-install leaks. Smoke check after everything’s in and save time, brain cells.
My butt isn’t calibrated, but Dragy says 0-60 is sub 4.2, so a slight improvement. I haven’t done a dyno to compare torque curve, so I may go do that after this next oil change. Nice to have a good speed shop 5 minutes away, conveniently across the street from my indie.
I find the Spyder tube easier to take on/off than the old 74mm, probably due to increased diameter=increased flex.
This is a source reference. Confirm exact model applicability in the original material.
