Beiträge von stuart

From what I've read, most all aftermarket exhausts either reduce HP or don't add any except the Supersprint. The Dinan is supposed to add 10 at redline and little or nothing below 5000 rpm, but their system is just a stock setup with the baffles cut out and some chrome tips welded on. They have the nerve to charge upwards of $2,200. U.s. for this. LOL. The SuperSprint is supposed to add 5HP roughly down in the lower midrange and builds to 29HP (if I'm remembering it right) near redline. The stock system seems dificult to beat.

I am thinking this is a mixture issue, as higher flow often reduces power in one area and gaines it in another, but higher flow should never reduce power everywhere unless the mixture isn't being corrected as I suspect is the case here.

I recently posted a question / speculation on this very topic under modifications.

I had the Supersprint on my last 850i (1992) and liked it very much. Nice burble at idle but quiet at 700 RPM and above.

I'm shopping for a system now for my '91. Best price I've seen is $1290. u.s. on the SuperSprint.

I had a problem with that on my 750. The sender is a plastic float in a plastic tube about 30-35mm around, located next to the fuel pumps. It is pretty easy to get to. On my car the plastic tube had developed a crack and a piece of it where it had cracked was hanging into the area where the float went up and down. This was holding the float near the bottom so the car read near empty no matter what amount of gas was in it.

I pulled the sender out, trimmed off the offending bit of plastic and reassembled. Worked perfect after that. Total time about 15 minutes. The fuel tank bung should be under trunk carpet, held in place with 8 10mm nuts. Easy to recognise as it also has an electrical cable and 2 fuel lines going to it. Strongly recomend disconnecting batteries first.

Bently book lists tightening torque as 10NM (89in lbs) for the M6 nuts, 23NM (17in lbs) for the M8 nuts, and 2NM (18in lbs) for the 10 to 16mm diameter hose clamps. Is there anyone in the world so anal retentive that they use an inch pound wrench to tighten their hose clamps? If so, my car needs a detail job, I'll but the plane ticket.

Exhaust has been covered many times on Roadfly I know, people seem to think / know that most of the systems loose power or don't add any. Same with K&N filters. I had the Super Sprint on my last 850 and liked it. I've heard that it is the only brand that actually adds power.

What I'm wondering is, if the reason that the other brands and even headers, race cats, straight pipes etc don't add power, is simply because they lean down the engine too much. I havn't seen anything that says that anyone of the people who have dynoed their cars have used an exhaust gass analyzer while doing the dyno pulls.

While it's true that durring closed loop operation (part throttle) the O2 sensor dictates and corrects mixture, at full throttle, (presuming 850's run as do other cars) the system goes into open loop, using preset mixture maps. Richening the mixture should get back the lost HP and realize the hoped for HP gain no? Our fuel pressure regulators are vacuum refrenced it seems. The aftermarket makes adjustable vacuum referenced fuel pressure regulators, any thoughts on this? Just remove the exhaust behind the cats and play with mixture while on the dyno and we could know just how much room for improvement there is in the exhaust.

A simple test before buying and installing regulators would be to run the car stock with an exhaust gas analyzer and compare the readings to those of a follow up run with no air filters. Does the car get leaner? Then unbolt the stock cat back exhaust, and do a third run, does the car get leaner? How far away from ideal? 12.8 to 1 is ideal for power is it not? Car probably set to run leaner than that for emissions though, and that may be why any increase in airflow causes HP loss.

Thanks, yeah I had read that somewhere, I really am curious as to what the seats weigh though. Also I want to thuroughly clean the carpet and install new mats before driving the car.

By swirl marks, do you mean lots of very fine scratches in the wax or clear coat? If so, the solution is simple. My friend found the answer. His black 1993 RX7 looks perfect, and I mean perfect. The scratches come from the type of cloth you are usind to buff out the wax. Cotton and terry cloths all leave these scratches. The cloths to use are the microfine towels. They are available here in the USA at any Walmart or major chain store. They come in a light green and light blue. They are small and a few bucks a piece, but they are the only choice for a black car, period! You'll use two to do your car, and they wash in the wash machine. They are clingy, so if you put them in the dryer with other things like towels, they will have lots of junk stuck to them when you pull them out. They say they are good for drying, but they are really not.

For the last 2 years I have been attending the Barrett Jackson auction in Arizona where I lived untill recently. There I have the opportunity to talk to the heads of McGuires car wax company. They always have their tractor trailer parked there next to the staging lanes, where the cars sit right before they go across the block. 2 years ago I was having a problem with their gold class car wax clouding. They told me I was using too much product. They were right. This year my friend and I tried their synthetic chamoises and they are wonderfull. They are a heavy cheese cloth looking piece of synthetic fabric that absorbs an amazing amount of water and does not leave streaks. They worked so well we couldn't resist the urge to test them out by cleaning off and detailing the nearest wet car (it had just drizzled a bit) some ladies Edsel was the closest vehicle and as such got the full treatment, trunk jams, door jams, under hood etc... I strongly recommend them and would insist on the microfine cloths for everyone here if I could. The best thing to apply wax with (according to McGuires) is their yellow foam pads or something like it. They are a bit stiff and do not apply wax very thick, but that is what you want, a thin even coat. I have been using the yellow foam pads to put wax on and the microfine towels to take it off on my black 750iL and have not seen a swirl mark since. Hope this helps.

I recently sold my 1990 750iL. Bently has a service manual for the 7 series. It was indespensable for the 7 and now for the 8. The front suspension and drivetrain are the same as is most of the dash. Most all dealers of Bently books will tell you that Bently does not print this book, but they are mistaken, the Bently stock nomber is B794

Perhaps I was too harsh in my comments. It is true that the extra tire size and superior compound and construction of your currunt setup will outperform the stockers, however the extra 10-12 LBS is still a handicap. This will not be noticed in terms of grip unless the road is rough. The extra weight slows acceleration and deceleration and decreases the suspentions ability to keep the wheel on the road. When the wheel hits a bump, the heavier wheel gets more energy put into it, which the suspension has to absorb. The extra energy causes the wheel to go higher than it would otherwise and also take longer to return to the ground. It then also has more energy on the way down and an increased tendancy to want to bounce back up again.
The net effect of this to the driver is a harsher ride and less grip when going around a corner with rough pavement. The slower acceleration will probably not be noticable. Sprung weight vs. unsprung weight, that is key to good handling and to a good ride. Rotating mass being the worst offender to performance. Lighter wheels take more engineering and carefull metalurgy to find the ballance between strength and weight, and are often more expensive as a result, one exception to this seems to be Enkei, the rims of theirs that I have used have always been about as light as anything available, on the other hand, Konig's weights have always been on the heavy side. Both manufacturers producing the current styles and both low price leaders.

Perhaps I was too harsh in my comments. It is true that the extra tire size and superior compound and construction of your currunt setup will outperform the stockers, however the extra 10-12 LBS is still a handicap. This will not be noticed in terms of grip unless the road is rough. The extra weight slows acceleration and deceleration and decreases the suspentions ability to keep the wheel on the road. When the wheel hits a bump, the heavier wheel gets more energy put into it, which the suspension has to absorb. The extra energy causes the wheel to go higher than it would otherwise and also take longer to return to the ground. It then also has more energy on the way down and an increased tendancy to want to bounce back up again.
The net effect of this to the driver is a harsher ride and less grip when going around a corner with rough pavement. The slower acceleration will probably not be noticable. Sprung weight vs. unsprung weight, that is key to good handling and to a good ride. Rotating mass being the worst offender to performance. Lighter wheels take more engineering and carefull metalurgy to find the ballance between strength and weight, and are often more expensive as a result, one exception to this seems to be Enkei, the rims of theirs that I have used have always been about as light as anything available, on the other hand, Konig's weights have always been on the heavy side. Both manufacturers producing the current styles and both low price leaders.

Just a thought. Don't use AC Schnitzer wheels if you care the least bit about performance. Unlike most 18" wheels that weigh 18-20 LBS, the AC Schnitzers always seem to weigh 30 lLBS or more. Big handicap. Though the polished ones on the black car one of the members has are nice, one of my favorite "looking" wheels.

Just a thought. Don't use AC Schnitzer wheels if you care the least bit about performance. Unlike most 18" wheels that weigh 18-20 LBS, the AC Schnitzers always seem to weigh 30 lLBS or more. Big handicap. Though the polished ones on the black car one of the members has are nice, one of my favorite "looking" wheels.

I am on my 2nd 850 now, this one a '91 with 49,800. on the clock. When I was looking for my first one last year there was a black and tan 91 850 manual trans for sale in Texas USA with 8,300 miles on it if I remember. The owner had always stored it in a climate controlled garrage, it had never seen rain, was all stock except for a staggered set of M-Parallels recently installed, and he had purchased a "NEW" lower gear ratio rear-end but had not installed it. He apparently had 17 or so collector cars and had to sell one to make room for something he had ordered. I think he was asking 35,000 US or thereabouts.

Yes there are superchargers for the 850 i , ci, and csi. Konig makes kits for these, they include pistons, superchargers and intercoolers. Prices are listed on their site in Euros which are near dollars usually. Hp is 470 for the i and 500 for the CSI. The kit is E 18,000. and E 25,000. installed. 0-100 kilometers, (0-62 mph) is claimed at 5.4 sec for the i, as opposed to about 6.8 sec for 0-60 mph with comforti cjips and Supersprint exh as tested in my '92 850i. With the horrific weight and daunting complexity of these cars, making them quick is prohibitively expensive. They're best used as the GRAND Tourerers they were designed to be and buy a fast car to get your kicks.

That's true, they do seem to back-ordered. However, I called my old dealer and they happened to have 4 sets in stock. I suggest you call around, if you don't have the dealer do the work, they will probably charge you for the parts, each bag is $40. Don't know yet if one bag does each headlight or one adjuster. We think it is one light, will know next week. In the scheme of things, $80 isn't much to be able to see where you are going, concidering plug wires and dist caps run $600 on these cars.

Under any of the meetings sections I find pics and dates of past meetings, but no info about any set or proposed future meetings. Is there a place for these posts that I am missing or are there no proposed future meets?

There seems to be a quiet recall on these. The parts dept of the local dealer (in Arizona) told me there was a kit of parts to fix these. (he showed me the bag of stuff which he had in stock) It consisted mainly of new adjuster wheels that had set screws to keep them from falling off.
There was no charge for the parts and he even told me that the service dept would install them for free.
Turned out that the one adjuster that was bad was a result of a problem with the bucket, not the adjuster, (can you say "big bucks"?) however they did do the other side no charge.
I believe I only had a few months left to have it done, so there may be a 10 year time limit or something. '93 and later should be fine.
The 91 I just bought has all 4 fallen off. The small bag of parts was 8 bucks or so if I'm recalling it right and shouldn't be hard to install. I just trailered the car here to Detroit so it will be a while to I get around to it as it's cold here and the car wont be driven again till spring.

Bilsteins simply drop in stock non EDC struts, I did them, (after removing struts from car which is easy and after compressing spring which is pretty easy as well). No allignment required as the adjusters arn't loosened. I hear however that the EDC struts can be rebuilt (refurbished) for about $200 each. Can't remember where I saw that.
By the way, the 91 850 I just bought has EDC (unfortunately) they work fine as the car had 49,800 on it when I bought it recently. However I'm dying to lower the front a 1/2 inch, or lower the front 3/4 of an inch and the rear 1/4 to 1/2 an inch.
I know Dinan used to resell springs for this but no longer does, is there and other manufacturer making them or some low miles used ones out there?

Under "sticky" I read the prices for Bilstein and springs and wanted to say that I loved the H&R springs on my '92, 1.25" drop in ft and 1" in rear. $300. I bought Bilstein Sports all the way around for around $600-650 from BMA and installed them myself. I have a pic of my car with the springs and M-Parr wheels on it, it was really choice, I don't think you could do better for any price.

I'm a stereo nut. Been building car stereos for about 14 years now. My 92 must have had a system in it before because there were MB Quart speakers laying loose in the stock locations.
*I replaced the rears with 5 1/4" Boston Acoustics co-axles and replaced the capacitor with one of the same value made out of metalized polypropolene. (old trick that makes $5 tweeters sound as good as $180 dollar ones). I mounted these on pieces of 1/4" hardboard cut bigger than the opening and screwed them in from the bottom, then sealed the irregular shape with Butyl Tape. End result, the back sounder better than the front of all but a few competition cars I have ever heard, and keep in mind I'm a tube amp, vinyl guy who has to build my own speakers because I can't afford a decent set (20,000-90,000 dollars)).
For the front I remover the ported chamber in the kick pannels and made 1/4" hardboard pannels that fit the area and backmounted 6.5" Boston mid-woofers to the back. Once you remove the chamber you have a nice sized steel enclosure to work with, an installers dream. I then used a Makits sawzall to open up the rest of the slots impressed on the kick pannel to accomodate the bigger speaker. My favorite car tweeters are 1"polly Neo 2T (I think) that are no longer in production). You can buy them through the parts dept of Boston. I ran the mid full range and put 4.5 ohms of resistance using ceramic Axiom resistors in line on the pos wire, and then, between that and the tweeter I placed a 6.4 mfd metalized polypropolene capacitor. After many hours of listening tests I determined the best placement for the tweeter was on the dash pointing straight up just inside the A pillars. This reflects off the glass and gives a nice high soundstage as well as reflecting towards the other side of the car a bit so each passanger can hear both sides. I believe this combo sounded as good or better than any competition winning IASCA vehicle I have heard and for about $400. dollars total, not $3,000 or so. I was using McIntosh amps though, and had made a bandpass woofer box for a $30 10" Rockfor Fosgate woofer I found which I fired through the ski pass-through up into the grill above the rear storrage bin. The '91 I just bought is all stock and low miles, so I am going to try to leave it stock.

I thought they were fine, then again I wasn't tracking the car. Just for looks though I ordered a set of 4 Zimmerman cross-drilled rotors from BMA at a cost of $278 I think. Direct replacement. Those calipers in the pic above are killer though. Droollllllll.

I thought they were fine, then again I wasn't tracking the car. Just for looks though I ordered a set of 4 Zimmerman crossdriller rotors from BMA at a cost of $278 I think. Direct replacement. Those calipers in the pic above are killer though. Droollllllll.