Parts testing and Dyno Tuning GT3 w/ G6
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It shouldnt make a difference. Pressure loss from throttle body to inlet is given by the box design. The higher the airflow, the higher the penaltiy for the worse box. It should be even bigger gap between the box when air is forced into it because the box with the weaker airflow will lose more of the overpressure given at the inlet.
I can not believe a 10hp difference, thats so much for a filter box... would mean the toruing box is rubbish. Could be any other factor involved? Like sucking in warm air?
I can not believe a 10hp difference, thats so much for a filter box... would mean the toruing box is rubbish. Could be any other factor involved? Like sucking in warm air?
FWIW, Dundon talks about the touring air box and 93mm throttle body improving intake here:
https://www.dundonmotorsports.com/pr...6XNXrtFT6Y5hsM
https://www.dundonmotorsports.com/pr...6XNXrtFT6Y5hsM
You'll lose a few MPG, thats the only drawback. You just need to get it tuned.
Last edited by xBoost; Mar 14, 2026 at 06:56 PM.
5th Gear
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What do you recommend for tuning these cars? I'm not all too familiar with the subject though I see people talking about the Cobb Accessport quite a bit. The part that seems confusing to me is that if I take it out to someone with a dyno, I'll have to show up with e85 in the tank which I can't do because the car will be on the standard tune on the way there? What would you say is the best way to go about this?
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Not matter what i did for IAT temps and cool down time, the Touring box lost power. 8-9whp in the chart i posted. The IAT would climb faster cause I didnt have the "Y" inlet, but lets assume, we have ideal conditions, what will happen? It wont lose as much? It would make the same power? Thats best case scenario in my test.
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What do you recommend for tuning these cars? I'm not all too familiar with the subject though I see people talking about the Cobb Accessport quite a bit. The part that seems confusing to me is that if I take it out to someone with a dyno, I'll have to show up with e85 in the tank which I can't do because the car will be on the standard tune on the way there? What would you say is the best way to go about this?
only 8 was the piece I was missing
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I will be going to the other dyno jet I use soon to back up the numbers. I wanna confirm on different dynos since my baseline is quite high (super happy about that if it checks out.)
But the gains/losses can be confirmed since the same dyno was used for everything.
But the gains/losses can be confirmed since the same dyno was used for everything.
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While track and driving style dependent, I'm pretty sure that you'll find it tending towards understeer at higher speeds even with 10 deg. I don't have canards but run the cup front lip on my .2 together with lower cup fender liner/tunnels which do meaningfully increase front DF. But my experience was on the Ring where there's loads of corners between 100-160 MPH.
There's this video on YT with Jackie Ding driving a car with Verus aero and he had it set to 4 or 5 degrees even with the Verus splitter on.
Easy to experiment with at the track obviously. The low angle risers go all the way up to 9 degrees so I do think that's the most useful one to have on.
There's this video on YT with Jackie Ding driving a car with Verus aero and he had it set to 4 or 5 degrees even with the Verus splitter on.
Easy to experiment with at the track obviously. The low angle risers go all the way up to 9 degrees so I do think that's the most useful one to have on.
Car is definitely faster. Super happy with results. Did some datalogging today, everything checks out. Next important test is a track day! Hopefully we get good weather that lines up with a track day before summer rolls around.
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Car sounds good, plot shape looks good. Too bad we can't see the correction factor numbers to compare with the street numbers. Dynojets do read "high" compared to what we use here.
7.4s 100-200 should be pretty close to 500 HP uncorrected/actual at the crank.
7.4s 100-200 should be pretty close to 500 HP uncorrected/actual at the crank.
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State side dynojet is the industry standard. Thats why its my go to. And why I went to 2 different dynos to verify.
Im not gonna front man. I dont believe the numbers from the .1 you posted LOL. Could have been a fluke.
No, I sold them. I prefer the sound from the stock sides and GMG center delete. The fact I didnt see any gains was unfavorable but ultimately, the quietness from stock side mufflers while street driving and the tone with the gmg when the valves open was perfect for me.
I like the cup car sounds with dundon but didnt like the loudness driving under 5k. And with the OEM muffler WOT was to quiet.
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Heared that now 2 times... xBoosts 991.1 and JCviggens 991.2 didn't gain any power from the dundon street headers. xBoost did a lot of testing as we can read here... any I know where JCviggen was for measurement/tuning and thats one of the most experienced porsche tuners I know.
Doesn't put a good light on the Dundon headers. I'm thinking about making my own measurements. Will be expensive unfortunately to dyno, swap headers, dyno and propably swap back... hmmm...
Doesn't put a good light on the Dundon headers. I'm thinking about making my own measurements. Will be expensive unfortunately to dyno, swap headers, dyno and propably swap back... hmmm...