De-Plenum'd my car yesterday - Big Improvement
#31
04-16-2008, 06:43 AM
I think you need to re-read my post.
I said my situation wasn't typical. I'd also had correspondence with Greg at RSS to make sure my installation was correct. Despite this the car didn't run right. Now, having measured the dimensions of the plenum, it turns out to be the wrong size for my car and I've invited RSS to comment on this. I've also said that I will re-try the plenum once my headers are fitted and if RSS can confirm that it's the correct part. (I don't know how it can be when it's longer than the standard tee).
Please will you explain to me how that is 'trashing a sponsor's product'? 'Giving it every chance to do as claimed' would be closer.
Anyway you'll only ever see/read what you want to see/read. Never let the truth get in the way of a chance to stir things eh?
Ian
I said my situation wasn't typical. I'd also had correspondence with Greg at RSS to make sure my installation was correct. Despite this the car didn't run right. Now, having measured the dimensions of the plenum, it turns out to be the wrong size for my car and I've invited RSS to comment on this. I've also said that I will re-try the plenum once my headers are fitted and if RSS can confirm that it's the correct part. (I don't know how it can be when it's longer than the standard tee).
Please will you explain to me how that is 'trashing a sponsor's product'? 'Giving it every chance to do as claimed' would be closer.
Anyway you'll only ever see/read what you want to see/read. Never let the truth get in the way of a chance to stir things eh?
Ian
From what I've read in this thread, you didn't dyno it, so I'm not sure how you can make any of these claims. Not to mention you're questioning the design of the product with no real science to back it up. To claim that your butt can feel an insignificant increase or decrease at a particular rpm is a bit of a stretch. Such as your car revving quicker from 6K to 7.2K. How would you even measure that? It probably takes a second or less depending on the gear.
All I'm suggesting is that you should have done a before and after dyno rather than trying to describe what you're experiencing and disparaging a product. I still don't really understand what you're getting at with regards to the shape of the plenum. I don't remember ever holding them side by side, but if they are slightly different I'm sure it's intentional to maximize and smooth airflow entering the TB.
How do you know you got the wrong size? Did Greg confirm this? I would assume that the 996, 997, and 997S would all use the same plenum but I don't know that for sure.
#32
04-16-2008, 07:02 AM
I did read your post. I'm not trying to be disrespectful, but it just doesn't make sense.
From what I've read in this thread, you didn't dyno it, so I'm not sure how you can make any of these claims. Not to mention you're questioning the design of the product with no real science to back it up. To claim that your butt can feel an insignificant increase or decrease at a particular rpm is a bit of a stretch. Such as your car revving quicker from 6K to 7.2K. How would you even measure that? It probably takes a second or less depending on the gear.
All I'm suggesting is that you should have done a before and after dyno rather than trying to describe what you're experiencing and disparaging a product. I still don't really understand what you're getting at with regards to the shape of the plenum. I don't remember ever holding them side by side, but if they are slightly different I'm sure it's intentional to maximize and smooth airflow entering the TB.
How do you know you got the wrong size? Did Greg confirm this? I would assume that the 996, 997, and 997S would all use the same plenum but I don't know that for sure.
From what I've read in this thread, you didn't dyno it, so I'm not sure how you can make any of these claims. Not to mention you're questioning the design of the product with no real science to back it up. To claim that your butt can feel an insignificant increase or decrease at a particular rpm is a bit of a stretch. Such as your car revving quicker from 6K to 7.2K. How would you even measure that? It probably takes a second or less depending on the gear.
All I'm suggesting is that you should have done a before and after dyno rather than trying to describe what you're experiencing and disparaging a product. I still don't really understand what you're getting at with regards to the shape of the plenum. I don't remember ever holding them side by side, but if they are slightly different I'm sure it's intentional to maximize and smooth airflow entering the TB.
How do you know you got the wrong size? Did Greg confirm this? I would assume that the 996, 997, and 997S would all use the same plenum but I don't know that for sure.
The differences aren't that subtle - hence why they're noticeable! I'm not one to rely on the butt dyno for measuring small or subtle increases or otherwise in power delivery; I agree it isn't possible. But in this case, the changes in how the power is delivered (in the mid range particularly) are quite obvious.
The difference in the dimensions of the plenum when compared to the tee on my car are a simple matter of fact. Assuming you are looking at both from above, the overall width is the same but the dimension from the centreline of the outlets to the face of the throttle body mounting surface is approx 1" longer on the plenum. This is both easy to measure and easily confirmed by the fact that the support bracket won't fasten to the rubber mount any more.
Maybe as you say, this size change is deliberate for air flow. Maybe I just have the wrong part - I don't know. But none of this is trashing the product! If I have the wrong part I'm happy to fit the right one and try again. I personally believe the plenum is a good idea that ought to work and nobody was more surprised than me when it did the opposite. I would just like to work out why either 1) I'm getting differing results from everyone else or 2) why eveyone else thinks their cars are faster when they aren't!! ;-)
Ian
#33
04-16-2008, 07:08 AM
Ian:
How different are the dimensions of your plenum vs stock as compared to the photos in this thread?
https://www.6speedonline.com/forums/...d.php?t=125214
How different are the dimensions of your plenum vs stock as compared to the photos in this thread?
https://www.6speedonline.com/forums/...d.php?t=125214
#34
04-16-2008, 07:22 AM
Ian:
How different are the dimensions of your plenum vs stock as compared to the photos in this thread?
https://www.6speedonline.com/forums/...d.php?t=125214
How different are the dimensions of your plenum vs stock as compared to the photos in this thread?
https://www.6speedonline.com/forums/...d.php?t=125214
Please see the attached image - the dimension I've shown is approx 1" longer in the plenum than it is in the stock tee on my car.
Edit: And the tee piece on my car looks nothing like the one in the pic. Totally different part.
Last edited by Ian_UK1; 04-16-2008 at 10:06 AM.
#35
04-16-2008, 08:14 AM
Registered User
Join Date: Nov 2004
Location: Wash DC Metro
Age: 51
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#37
04-16-2008, 08:36 AM
Registered User
Join Date: Nov 2004
Location: Wash DC Metro
Age: 51
Posts: 176
Rep Power: 27
My butt is very sensitive, so the dyno is probably going to be pretty accurate.. 
what am i saying... I still dont have my car back yet. My baby is sitting outside in the cold/rain with bird droppings on it at the bodyshop..
what am i saying... I still dont have my car back yet. My baby is sitting outside in the cold/rain with bird droppings on it at the bodyshop..
#38
04-16-2008, 09:12 AM
"This is both easy to measure and easily confirmed by the fact that the support bracket won't fasten to the rubber mount any more."
I did not have this problem with my Plenum install. It fit perfectly.
I did not have this problem with my Plenum install. It fit perfectly.
#40
04-16-2008, 09:25 AM
This is interesting - If the part I have isn't correct, then I've no wonder the performance of the car wasn't as it should have been.
Either I have the wrong plenum or the tee on a UK spec car is different and can't be replaced with the same plenum as North American cars. Irrespective, the plenum I have is a different shape to the tee and is therefore altering the inlet tract length. I'm sure that would explain why my results are different to most others experiences.
Ian
Either I have the wrong plenum or the tee on a UK spec car is different and can't be replaced with the same plenum as North American cars. Irrespective, the plenum I have is a different shape to the tee and is therefore altering the inlet tract length. I'm sure that would explain why my results are different to most others experiences.
Ian
#42
04-16-2008, 10:01 AM
Quick plea for help from David Dodd. David do you have the part number from your tee piece (as the plenum seems to be a size-for-size replacement for it)? We can then compare it to the UK part number. Thanks in advance.