Opinions on my GT3076R setup
01-02-2013, 05:45 PM
#61
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The factory 968T airbox is the same as the 951, with the same rectangular restriction before the AFM.
The 968TS exhaust is an odd beast. If I remember correctly the downpipe is the same doubled-skinned unit carried over from the 951, then the (single) piping goes into a shorter but surprisingly larger cat, then into a triangular backbox like on the 968 NA from which dual piping goes the rear muffler, then we have this dual piping going to the twin tail pipes.
Will be interesting to see if Raj's original exhaust is similar.
The 968TS exhaust is an odd beast. If I remember correctly the downpipe is the same doubled-skinned unit carried over from the 951, then the (single) piping goes into a shorter but surprisingly larger cat, then into a triangular backbox like on the 968 NA from which dual piping goes the rear muffler, then we have this dual piping going to the twin tail pipes.
Will be interesting to see if Raj's original exhaust is similar.
Below is a comparison to show the difference between a 968 turbo S cat and a 951 cat.
Last edited by RajDatta; 01-02-2013 at 07:50 PM.
01-02-2013, 06:08 PM
#63
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Can't see any pics Raj?
I know you want to maintain stock components as much as possible but if you have essentially a 951 exhaust setup I'd be updating that at the very least. That's a heavy and restrictive setup for sure. Have you ever picked up the whole exhaust? Weighs a ton and the twin skin thing goes down to a really small aperture. A new downpipe and 3" system would be on my agenda.
I know you want to maintain stock components as much as possible but if you have essentially a 951 exhaust setup I'd be updating that at the very least. That's a heavy and restrictive setup for sure. Have you ever picked up the whole exhaust? Weighs a ton and the twin skin thing goes down to a really small aperture. A new downpipe and 3" system would be on my agenda.
01-02-2013, 06:17 PM
#65
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Can't see any pics Raj?
I know you want to maintain stock components as much as possible but if you have essentially a 951 exhaust setup I'd be updating that at the very least. That's a heavy and restrictive setup for sure. Have you ever picked up the whole exhaust? Weighs a ton and the twin skin thing goes down to a really small aperture. A new downpipe and 3" system would be on my agenda.
I know you want to maintain stock components as much as possible but if you have essentially a 951 exhaust setup I'd be updating that at the very least. That's a heavy and restrictive setup for sure. Have you ever picked up the whole exhaust? Weighs a ton and the twin skin thing goes down to a really small aperture. A new downpipe and 3" system would be on my agenda.
01-02-2013, 06:19 PM
#66
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Buying a "good" turbo won't buy me anything.
01-02-2013, 06:58 PM
#67
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I understand you are never going to be short of power with your engine, but I am not sure you will gain what you are looking for if you change the turbine housing, I expect a retune will be fine for your needs.
01-02-2013, 07:03 PM
#68
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BTW, are the pictures viewable to everyone?
01-02-2013, 07:06 PM
#69
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IMO these turbos are made to be ran with 3" exhausts. Even with your engine size, 2.5" is just to small.
I reckon get a full 3" exhaust, 2 large blow through SS mufflers, or 1 with a cat (up to you, i rather 2 mufflers) and a retune or consider vitesse chips or rogue tuning chips.
Not sure how restrictive the airbox is, but to find out dyno with it on, and one with it off, and it'll show you the results.
Patrick is right, the stock 951 exhaust is quite heavy, when i replaced mine with a 3" turbo back, it was much lighter.
I reckon get a full 3" exhaust, 2 large blow through SS mufflers, or 1 with a cat (up to you, i rather 2 mufflers) and a retune or consider vitesse chips or rogue tuning chips.
Not sure how restrictive the airbox is, but to find out dyno with it on, and one with it off, and it'll show you the results.
Patrick is right, the stock 951 exhaust is quite heavy, when i replaced mine with a 3" turbo back, it was much lighter.
01-02-2013, 07:21 PM
#70
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I'm not getting the exhaust pics either.
Is the compressor getting its' air from the hot engine bay, around the coolant tank? It's a turbo phenomenon that it takes alot more exhaust energy to make boost from hot air as opposed to the exhaust needed to make boost from cold intake air. That would be an issue right there. You might just have a few of these "less than ideal" circumstances; from air entry, all the way back to the tailpipe, which all pile up for you to lose 500+ RPM worth of spool. Attention to detail when engineering a system can pay huge dividends. Might be a diffcult decision when wanting to keep the car stock looking.
How does the car feel when driving it?
Is the compressor getting its' air from the hot engine bay, around the coolant tank? It's a turbo phenomenon that it takes alot more exhaust energy to make boost from hot air as opposed to the exhaust needed to make boost from cold intake air. That would be an issue right there. You might just have a few of these "less than ideal" circumstances; from air entry, all the way back to the tailpipe, which all pile up for you to lose 500+ RPM worth of spool. Attention to detail when engineering a system can pay huge dividends. Might be a diffcult decision when wanting to keep the car stock looking.
How does the car feel when driving it?
01-02-2013, 07:23 PM
#71
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IMO these turbos are made to be ran with 3" exhausts. Even with your engine size, 2.5" is just to small.
I reckon get a full 3" exhaust, 2 large blow through SS mufflers, or 1 with a cat (up to you, i rather 2 mufflers) and a retune or consider vitesse chips or rogue tuning chips.
Not sure how restrictive the airbox is, but to find out dyno with it on, and one with it off, and it'll show you the results.
Patrick is right, the stock 951 exhaust is quite heavy, when i replaced mine with a 3" turbo back, it was much lighter.
I reckon get a full 3" exhaust, 2 large blow through SS mufflers, or 1 with a cat (up to you, i rather 2 mufflers) and a retune or consider vitesse chips or rogue tuning chips.
Not sure how restrictive the airbox is, but to find out dyno with it on, and one with it off, and it'll show you the results.
Patrick is right, the stock 951 exhaust is quite heavy, when i replaced mine with a 3" turbo back, it was much lighter.
I am perfectly happy with my current power (which is still 100hp north of what the factory cars made). Just want to make sure I can maximize the setup within the constraints of my design.
A small video showing a 968 on full tune getting passed by my turbo right at 1:50 mark. The car is fast even with such a restrictive exhaust. You barely hear the car go by.
I lifted off as soon as I passed him.
Regards.
01-02-2013, 07:24 PM
#72
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Pictures are here:
https://rennlist.com/forums/members/...0&ref=gnr-prev
Why does it go from 1 to 2 pipes after the wastegate tie in?
https://rennlist.com/forums/members/...0&ref=gnr-prev
Why does it go from 1 to 2 pipes after the wastegate tie in?
01-02-2013, 07:30 PM
#73
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I'm not getting the exhaust pics either.
Is the compressor getting its' air from the hot engine bay, around the coolant tank? It's a turbo phenomenon that it takes alot more exhaust energy to make boost from hot air as opposed to the exhaust needed to make boost from cold intake air. That would be an issue right there. You might just have a few of these "less than ideal" circumstances; from air entry, all the way back to the tailpipe, which all pile up for you lose 500+ RPM worth of spool. Attention to detail when engineering a system can pay huge dividends. Might be a diffcult decision when wanting to keep the car stock looking.
How does the car feel when driving it?
Is the compressor getting its' air from the hot engine bay, around the coolant tank? It's a turbo phenomenon that it takes alot more exhaust energy to make boost from hot air as opposed to the exhaust needed to make boost from cold intake air. That would be an issue right there. You might just have a few of these "less than ideal" circumstances; from air entry, all the way back to the tailpipe, which all pile up for you lose 500+ RPM worth of spool. Attention to detail when engineering a system can pay huge dividends. Might be a diffcult decision when wanting to keep the car stock looking.
How does the car feel when driving it?
Car feels great, super quiet, but very fast. The gearing is quite high for US, so I have to struggle to keep it in 6th gear on the highway. I am barely at 2800rpm at 80mph. And as you can imagine, with my tq curve, I would need to go down atleast 2 gears to get into the meat of the powerband.
01-02-2013, 07:30 PM
#74
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I understand your point. To maximise your set up... try replacing the cat. it could have had it. clogged. It's a possibility. There's nothing wrong with changing the cat to a higher flowing one is there?
Or go back to the original headers. or both?
Or go back to the original headers. or both?
01-02-2013, 07:35 PM
#75
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Pictures are here:
https://rennlist.com/forums/members/...0&ref=gnr-prev
Why does it go from 1 to 2 pipes after the wastegate tie in?
https://rennlist.com/forums/members/...0&ref=gnr-prev
Why does it go from 1 to 2 pipes after the wastegate tie in?