New Here, Performance Questions
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Joined: Apr 2007
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From: Reisterstown, MD
Already a paying rennlist member, as of today. 
)
Baseline dyno is a good idea. So when's the next dyno day in Maryland? Anyone care to organize one if there isn't one planned? I'm in Baltimore but I'm willing to travel around.
Will be checking the thrust bearing as soon as I get back in town... and I have an appointment for the timing belt retensioning on Tuesday (engine was rebuilt 2500 miles ago and this was recommended to be done about now by the rebuilder).
) Baseline dyno is a good idea. So when's the next dyno day in Maryland? Anyone care to organize one if there isn't one planned? I'm in Baltimore but I'm willing to travel around.
Will be checking the thrust bearing as soon as I get back in town... and I have an appointment for the timing belt retensioning on Tuesday (engine was rebuilt 2500 miles ago and this was recommended to be done about now by the rebuilder).
Under the Lift
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From: Buckeye, AZ
Mike:
Performance chips aren't useful for S4 as they can be for earlier cars. Forget that idea.
X-pipes are clearly helpful power-wise, depending on how well they are made (a simple 90 degree X is the least effective).
An RMB does nothing for power but wakes up the sleepy stock exhaust note and can be annoyingly loud with an X-pipe.
High-flow cats are iffy. I've seen even reputable ones fail smog after a year, and power gains seem marginal.
I'm not sure about headers or headers plus X-pipe.
After that, you're talking major mods. At one end you have relatively inexpensive SC kits. A bunch of us have done it, some even home-made . Even my modest SC kit makes me smile everytime I push the pedal down. There are far more agressive kits that take the power WAY up.
http://www.928motorsports.com/superchargers.html
https://www.928gt.com/pc-40357-1403-...arger-kit.aspx
After that you're talking stroker kits and many more $$.
Performance chips aren't useful for S4 as they can be for earlier cars. Forget that idea.
X-pipes are clearly helpful power-wise, depending on how well they are made (a simple 90 degree X is the least effective).
An RMB does nothing for power but wakes up the sleepy stock exhaust note and can be annoyingly loud with an X-pipe.
High-flow cats are iffy. I've seen even reputable ones fail smog after a year, and power gains seem marginal.
I'm not sure about headers or headers plus X-pipe.
After that, you're talking major mods. At one end you have relatively inexpensive SC kits. A bunch of us have done it, some even home-made . Even my modest SC kit makes me smile everytime I push the pedal down. There are far more agressive kits that take the power WAY up.
http://www.928motorsports.com/superchargers.html
https://www.928gt.com/pc-40357-1403-...arger-kit.aspx
After that you're talking stroker kits and many more $$.
Thread Starter
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Joined: Apr 2007
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From: Reisterstown, MD
Re: Thrust Bearing: Just read all of the basic info on checking the crankshaft play. I'm guessing/hoping that the engine rebuilder would have made the recommended modifications to prevent future failure. The work was done by a reputable shop: Authotherapy, in Gaithersburg, MD. I searched their name on this forum and found only one result, though. Anyone else have experience with them and know whether they're likely to have done these mods? I plan to call them when I get back in town.
My plan now is to actually be patient for once and hold off on mods until I can get the baseline dynowork done. I see a supercharger in my (distant) future, though...
My plan now is to actually be patient for once and hold off on mods until I can get the baseline dynowork done. I see a supercharger in my (distant) future, though...
Rocket Pilot
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From: gettysburg pa.
Hi Mike, I am local to you and could help you if you ever need it with the 928. I also have a highly modified s4 if you should ever wanna take a look/spin. I also used to play with the old 900 series turbos. Ever shim the gate in one of those? Rocket is an understatement, but the engine is done after two 1/4 mi. runs!
Kevin
Kevin
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From: NJ but from Boston
Charley,
get it in perfect tune and then go for the Motorsport X with Motorsport 100 cell cats. Contact Dave Lomas.
Increasing the exhaust pipe diameter nets a good gain. See www.928motorsports.
Carl estimates high 30 to mid 40's for HP gains with that set up.
The x pipe alone does not create much extra noise.
Good Luch
Rich
get it in perfect tune and then go for the Motorsport X with Motorsport 100 cell cats. Contact Dave Lomas.
Increasing the exhaust pipe diameter nets a good gain. See www.928motorsports.
Carl estimates high 30 to mid 40's for HP gains with that set up.
The x pipe alone does not create much extra noise.
Good Luch
Rich
Thread Starter
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From: Reisterstown, MD
Originally Posted by Kevin Michael
Hi Mike, I am local to you and could help you if you ever need it with the 928. I also have a highly modified s4 if you should ever wanna take a look/spin. I also used to play with the old 900 series turbos. Ever shim the gate in one of those? Rocket is an understatement, but the engine is done after two 1/4 mi. runs!
Kevin
Kevin
So what does your "highly modified" 928 set up include?
Cheers,
Mike
PS: Learned more about the engine rebuild today. The mechanic who performed the work is VERY well versed in 928 S4s and in fact has one of his own.
I'll talk to him next week to make sure, but I have to think that he made at least some of the mods to prevent against future issues (hopefully this is not wishful thinking!). Looking forward to the kickdown bypass switch install. That will be my #1 mod.
Craic Head
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From: Jersey Shore, USA
Hey Mike,
Welcome to the club. +1 on the CDs from Jim Morehouse. Best investment I've ever made in any car (after my RL membership ).
For some serious mods do some searches on strokers and definitely check out Sterling's Variocam setup (link to his website from his sig: post 13 in this thread)
There's also a recent thread I started called 'how many horses' or something like that. Most of the 400+ people who responded also have links to the things they've done in their sigs.
Welcome to the club. +1 on the CDs from Jim Morehouse. Best investment I've ever made in any car (after my RL membership
).For some serious mods do some searches on strokers and definitely check out Sterling's Variocam setup (link to his website from his sig: post 13 in this thread)
There's also a recent thread I started called 'how many horses' or something like that. Most of the 400+ people who responded also have links to the things they've done in their sigs.
