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TOPIC: Moderate Performance Upgrades.

Moderate Performance Upgrades. 10 Oct 2012 18:40 #11760


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Hello All. I hope to pick your brains again.
1988 S4 Auto US spec 74k
Since my overheat issue has been solved by you all. I can start to put some energy and money toward making a few performance upgrades.
The only upgrade I have made has been a RMB which does work very well and the car sounds very nice. What are your feeling on things like ECU chips? There seem to be some dramatic claims out there. Installing X pipes. And changing out the air intake setup. I have seen a few products specifically a thing called a Blackbird twin air intake system. Actually any idea's that the community may have will be strongly considered and most likely undertaken right away. My goal is to make this lovely car the best it can be. I am very open minded.
Thank you guys in advance!

Robert
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Moderate Performance Upgrades. 10 Oct 2012 23:22 #11769


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Not sure any of the intake systems have proven to increase HP, but they may have and I just have not seen the dyno runs.

The X-pipe CERTAINLY produces HP and Tq gains! You might want to drop the RMB though as some say the car will be REALLY LOUD with that set up and as an '88 in TN I suspect you can dump the cats! Though the car will smell different and not in a good way w/o them. Some have put the factory rear muffler section back on and report that is just the right amount of sound for them w/ an X and no cats. The RMB change out on an '88 makes those cars sound just about PERFECT IMHO!

I'll let you know how my '95 sounds with X, high flow cats, and the Constantine (BSRC) RMB on it soon! I hope it will be back tomorrow. Of course the 89 and up cars all have the BIG resonators so they don't sound very loud at all with just the RMB change for instance (I MUCH, MUCH prefer my '88 to my '92 w/ RMB).

You can add a rising rate fuel pressure regulator as well as 35# Ford fuel injectors (at least I think I go the injector info correct...someone who has done it and knows more will jump in)...

Lets see, leave the stock air filter in place, it is better than a K&N...

You could put more aggressive cams in the car but they are pretty expensive and then you are really talking about some serious work as well...though you don't have to pull the engine or the heads, but it is still a big job.

I can't think of anything else...Oh, the biggest performance gain as far as acceleration is concerned would be to change to a later transmission with a shorter final drive ratio than the 2.20:1 in the '87-'89 S4's. I have a '90 trans in my '88 car now and holy crap is that car quick!
James
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Moderate Performance Upgrades. 10 Oct 2012 23:32 #11770


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Unfortunately, James, converters are a requirement in Davidson Co. After all, it is Al Gore country around here. :p
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The following user(s) said Thank You: gary209h

Moderate Performance Upgrades. 11 Oct 2012 17:29 #11790


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Austin, didn't even think of that, but Al Gore needs you guys to NOT pollute so he can fly his VERY DIRTY jet all around the world puking out all sorts of nastiness high into the atmosphere! Not to mention light his 22,000 sq. ft. mansion!
James
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Moderate Performance Upgrades. 11 Oct 2012 20:48 #11794


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Robert, the first thing you do to improve performance is to open up the exhaust so that the engine can exhale.
When you do this then it can take a bigger breath and the power happens.

The first thing I did was remove my cats and replaced it with a straight pipe.
By doing this I removed exhaust restriction and gained some power.

If your area requires you to keep the cats for emissions then you can still get a X-pipe and performance cats except it will cost more to get those horses. 20 - 25 hp
here is a link from the vender Roger (928rus)
http://forums.rennlist.com/rennforums/928-forum/584133-new-high-flow-2-1-2-cat-back-system-87-to-95-a.html?highlight=performance+cats

The next upgrade would be performance tuning or chips. I am not sure who has the best bang for the buck.

Brad
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Moderate Performance Upgrades. 11 Oct 2012 21:13 #11795


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I would completely stay away from the chips for your car. They'll be Autothority or the respective knockoffs. They add fuel, and really don't do anything else. I really don't think you need an adjustable fuel pressure regulator, the S4 unit works fine in even boosted applications. More fuel does not make more power. Your stock injectors should be fine also, unless they are all clogged, or you're planning on maxing out the stockers (supercharger).

If I had an Auto S4 I would do the EIS (I think that's what the "blackbird" is) that you're referring too. Roger sells something like that, and an x-pipe. Then take your car and have it sharktuned by someone who knows what they're doing. I would hazard a guess it would be pretty noticeable.

Other than Cam work like James said, you could throw on a supercharger. Both will require sharktuning as well.

Just my $.02, I'm not an expert by any means. But, so long as your car is RUNNING like it came from the factory, the exhaust/intake/tuning should bump a little in the fun factor. The supercharger would make it an ENTIRELY different car.
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Moderate Performance Upgrades. 12 Oct 2012 00:04 #11796


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Sharktuning is really a BIG DEAL...it will result in optimum performance! Finding someone who can do it well is another story! It is a GREAT way to go though! I have not done it to any of my cars yet, but I hope to someday! I'd love to do it to ALL of them that it can be done on!
James
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Moderate Performance Upgrades. 12 Oct 2012 06:05 #11801


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I have spoken to Roger and he actually recommended staying away from the Blackbird style intake. He stated it's more of the "bling" factor but really no proven performance results. I am aware of the Autothority Chips and did a bit of research on that process. I guess the people selling them think they are great but I will take a pass. With all of your fanstastic feedback I have decided to get the X-pipe put on supercats and just love my car. I have already installed a RMB. I would be truly grateful for a referral or the heads up on how to get with someone about "sharktuning". My goal in this process is to help my Baby breath and run the absolute best it can. Thank You James, Jon, Brad and my neighbor Austin. I remain grateful

Robert
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Moderate Performance Upgrades. 12 Oct 2012 07:02 #11802

Add the X pipe as recommended with or without hi perf cats for your area/choice.

Leave the perf chips, large injectors and rising rate fuel regulator alone...........all give very litle to no gains with a stock set up.

do get the car back to absolute best state of original tune which would be full maintenance with strong consideration for a intake r&r and replacement of all pertinent parts. when checking the tbelt set the cam timing properly.....yes they came from the factory not perfect.

Next thing would be to add PEMs to both fuel and ignition computers and Shark tune the car.

Once all done you can only then consider big cams and/or supercharging, turbo charging, big bore engine etc etc/

All of the above Ive done to my 88 S4........good luck :)
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Moderate Performance Upgrades. 12 Oct 2012 22:04 #11816


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Malcolm is quite correct. As to the RRFPR and big injectors, you asked what people were doing or had done, and I was only letting you know folks have done that. I have not and clearly Malcolm does not recommend them on a plain old stock engine and I am inclined to agree with him on that as well!

The X, Cats, RMB are really easy, the tuning less easy but more and more folks are doing it and it seems to be a valuable thing to do.

Also M is quite correct about the intake refresh. If they have never been changed (and they probably haven't) there will be some VERY crispy plastic plugs up under there as well as brittle and cracked fuel lines...if one of the fuel lines lets go it will be shark flambe'! You DO NOT want that! Few of us will be as lucky as one of our own who had that happen in traffic and had a random guy in a van follow him right off to the side of the road and run up with a fire extinguisher and put out his car fire, wait for the Pros and then go on his way w/o telling his name or accepting a small donation!! Talk about luck!!!

Also, BE SURE (since you have an auto) that the kick down switch is being engaged at full throttle. The difference that will make will be HUGE! There is an arm on a funky armature behind and attached to the back of the gas peddle. There is a round button with a hexagonal (I think) base that is attached to the fire wall behind the peddle. The arm should touch the face of the round part of the button when the gas is pressed almost all the way to the floor. When you do that at between say 40 and 55 miles an hour the car should kick all the way down to 2nd gear and REALLY get up and go! That is the way to test it. If you are rolling along at 45 just cruising you should be in 4th gear, and if the button is not being hit or is not working then when you floor it the car will only shift down 1 gear to 3rd...

Let us know!

BTW, the '95 is back and while I don't like the sound as much as the '88 (stock other than RMB) this is pretty damn good! It is WAY better than just an RMB on an '89 or newer car! As you might recall, the '95 just got an X, high flow cats, and the Constantine (Black Sea R&D) RMB. Looks VERY NICE and sound very nice (not in caps nice though! LOL!) as well! VERY HAPPY WITH IT! Oh, yea it works too...car is faster! I can feel it!
James
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Moderate Performance Upgrades. 13 Oct 2012 00:45 #11820


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pcar928fan;12161 wrote:
Also, BE SURE (since you have an auto) that the kick down switch is being engaged at full throttle. The difference that will make will be HUGE! There is an arm on a funky armature behind and attached to the back of the gas peddle. There is a round button with a hexagonal (I think) base that is attached to the fire wall behind the peddle. The arm should touch the face of the round part of the button when the gas is pressed almost all the way to the floor. When you do that at between say 40 and 55 miles an hour the car should kick all the way down to 2nd gear and REALLY get up and go! That is the way to test it. If you are rolling along at 45 just cruising you should be in 4th gear, and if the button is not being hit or is not working then when you floor it the car will only shift down 1 gear to 3rd...

This would also include proper Bowden cable adjustment.
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Moderate Performance Upgrades. 15 Oct 2012 18:17 #11857


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Jon B.;12165 wrote:
This would also include proper Bowden cable adjustment.

So true, thanks for the reminder Jon! And from a guy who has a 5spd no less! ;)
James
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