My car rattles and squeaks much worse on cold mornings. They subside somewhat as it warms up or sits in the sun on a parking lot. Drove it in the snow for the first time today... not very impressive at all. My wife has a new Park Ave with the same power train (sans super charger), and it gets along MUCH better than the Bonnie. Must be the tires and weight distribution. I assume the traction control eliminates too much power.
thanks for the info/advise. I didn't buy an ssei..don't really know why. Bought the car for my wife's 33rd bday. So no pulley change out involved. Anyone look into a turbo setup like on the 83 Buick Grand National. Just wondering if it is possible. started researching on this today. A buddy of mine said to keep the heat down in the engine bay, that i should remove the big plastic 3800 decorative cap. I got home from work the other day and pulled it off...MAN that thing was hot and holding in the heat...any suggestions/ideas on this subject.
Yesterday I modified and installed the Thrasher Cold Air Induction kit, following dmckeown's lead.
I really like hearing the supercharger 'scream' now when I nail it. And the car will completely obliterate the tires from a standstill now...
Here are my mods to date: 2000 Dark Bronzemist Metallic SSEi, 18 x 8" Konig Villain wheels, P255/45ZR18 Michelin Pilot XGT Z4 tires, 1.25” Saner front and 1" rear sway bars, polyurethane front and rear frame mount and end link bushings, Thrasher Cold Air Induction System, 3.25" Thrasher supercharger pulley, 71.5” Dayco Poly Cog belt, 180 degree thermostat, Jacobs Electronics Ultra Coil Packs and 8.5mm. Energy Core Spark Plug Wires, NGK TR55VX spark plugs (gapped at .065"), Valentine One radar/laser detector
As a former owner of a 87 GN, forget any mods in that direction. It will not ever work. GNs had a super duty tranny with an extra clutch pack to accomodate the near 300 hp generated. The center piece for the GN was rear wheel drive and a killer intercooler capable of dropping intake temps by 70 degrees. This technology will never work in a bonnie and if it did the tranny and drive train would disintigrate immediately. Heads, exhaust, camshaft, and intake are your best options to fullfill your need for speed.
I'm a relatively new owner of a 2000 Bonneville SSEi (black), and must say I am enjoying the car immensely. I've had it about 2 months and have around 3500 miles on it, so I drive it a decent amount. And after driving an SUV for the past 5 years, this is like getting a crash course in how much fun a car can be to drive.
I do have a couple of questions, however. I see a lot of people posting about getting the K&N Filter, and was wondering two things. One, where is the best place to get one? I would like to order online, and was wondering who might have the best price. Second, at the couple of places I've looked so far, they don't list a filter for the 2000 SSEi, so is there a certain one I need?
I got my replacement K+N filter at a performance parts store for $49.00 + tax. The part # for the 2000 SSEi is MM33-2086. I have seen posts in this Town Hall for online sites. You could also search for K+N's website for a link.
Thanks for the info. I've checked a couple of websites, but was just curious if anyone here knew of any good sites a bit off the beaten path that had a better deal.
Are you looking for more performance from your car ? I would say go right to a 3.4 or 3.25 pulley and consider the Thrasher Cold Air induction kit that I and intense01 have in our cars . If you post your email add. I will send you a photo of it in my 2000 SSEi , it looks great ! If you plan on going to a small pulley the 9" K&N cone filter in this CAI unit will let your car get all the air it needs . Both intense01 and I are running 3.25's and the CAI's and I am very pleased . Happy SSEing
Happy to hear you got the CAI in your car ! I'm hoping you can post some autotap reading's to compare with the old filter . At this point I am thinking with snickle we may get a boost from more fuel via a modified FPR , at least at WOT . How long did it take you to get it modified and in your car ?
What are you looking for , dimensions of the modified Thrasher air box to help you plan a better one or so that you can just make your own ? I could UPS you the cardboard mock up I made of the unit if that would be better . Send me your address if you want me to do that , you have my email
I picked it up last night after its weekend with the service manager. While taking it shopping on Cape Cod for a new Harley, he experienced all the rattles and vibrations I have been telling him about. He had all the door panels removed, added windshield sealant in spots, and reinstalled the panels very securely. He also did the same with the dash board. I drove the car aprox. 200 miles today and boy what a difference! It's still not as vibration/rattle free as my wife's Sienna, but at least it is now acceptable.
Well, I am looking forward to a bit more performance from the SSEi with the K&N Filter, and I also plan on having the car for several years, and investing in a reusable air filter also seems to be a good idea (esp since in our area, there are a good number of dirt roads). As for the new pulley or CAI kit, I don't know if I'm ready for that quite yet, but I wouldn't mind taking a look at it. you can send the shot to brian@mclaugh.com.
Also another question for those who have had experience with the SSEi in the snow, are the stock tires good for this or is there another set I should be looking at now that winter is approaching. We got our first real snow the other day, and even with the trac control on, things seemed pretty slippery. Definitely need to learn to feather the throttle better when taking off in the snow.
It's the tires. This is the worst front wheel drive car I've ever driven in the snow. Get better tires, the traction control is excellent but is limited by the poor (snow) tires. Stopping is not this car's strong point in dry conditions, but really bites in the snow. I feel like buying an old jeep and letting the SSEi rest out these nasty days in the garage. Boy does it scoot with the ice cold temps!
It's obvious that you are the lead for SSEi mods. You mentioned several in your posting. Could you give us an idea the improvements which each one made. What are they rated as performance improvements? 1 through
What are your 0 to 60 times. Did you use autotap at each mod to measure the change? What have you blown away on the road. Have you been blown away and by what?
I have done the K&N filter and am awaiting the pulley party which we are trying to arrange here in the Northeast. Eager to hear more of your comments
What about the limited slip differential they are talking about on the Granprix list? That would probably give the most bang for the buck in drag times.
Don't you guys have yearly emission testing? I think your exhaust system should sound like an Indy car. Again I think the envelope will be the lack of traction. I put Potenza re 90"s on my Gran National and was able to knock change out of my pockets on launch in any weather... they are Firestone now aren't they???
Here is what I know so far about the stereo possibilities on an SSEi- 1. Because of the type of electrical system that GM uses in our cars ( digital series buss ground), and because of more than just music that is processed thru the "head/amp" sytem of our cars, as well as the BOSE 1 amp deal, it is impossible to REPLACE the head, and not suffer serious electrical problems. 2. There is available, if you must have an aftermarket head unit, a cable/ harness which allows the head unit to remain in circuit, but allows a new head unit to go in the dash hole. ( The old head must be relocated behind the dash.) Since actuall "performance" gains in CD/Casstte/FM/AM will be negligable, this will be for cosmetic, and "feature" issues. The CD pre-amp signal from the " Bose" unit is for all intents and purposes the same as from an aftermarket unit. 3. Most "hearable" change will be realized from a change in speakers and amp. This is realativly easy, especially if you leave the oem head unit in place. The up side to doing this is the electrical system of the car, and things like door chimes, remote radio controls, on-star, etc. remain unaffected. 4. The amp that drives the speakers is located behind the rear drivers side back seat. This is replaced by an amp of your choice and must be connected to the head leads with a module from SOUNDGATE which allows the head unit to think it is still talking to the old amp. After this, the sky is the limit speaker wise. A six channel amp would work fine.
I can't seem to manage more than 14 mpg around town, even when I keep my foot out of it ALL THE TIME! Is this normal? Long highway trips with NO city driving get me 24.3 MPG max. Is this normal? I have a 3.5" pulley, but have not installed it yet. Will this adversly affect MPG? Is anyone using synthetic oil? If so, any comments?
When I lived where it snowed NJ and Mass, i always purchased four inexpensive steel wheels, and kept 4 really good, skinny ( comparitivly speaking) performance snow tires on them. When it got cold, I put away my "fat tire/wheels, threw on the four steel/snows, and it was magic! I would bet that would work great on the Bonnie. Living in Southeast Virginia, that is not a problem anymore! But when I lived up North, I looked forward to snow! Perhaps it was my Audi 5000 Turbo that made the difference, but four real snow tires would help any car.
I would love to keep the factory head unit if for nothing else; cosmetic purposes. I have never played a cassette, so that is not an issue either. Speakers, amps, and a cd changer are my only goals. The guys I talked to said they had no way of getting in between the head and the factory connection. I mentioned the soundgate stuff and they said it was for other older Bose systems. I got as far as finding a spacer to allow an aftermarket head unit to fit the huge dash openning, but an after market head unit was an act of a desperate man saddled with a bad sound system. My car gets lousy mileage as well... better than yours 17/27 (with the boost gauge never getting into the positive)! It got better after a couple of thousand miles; the 3.4 pulley did not affect the mileage at all except for I flog it more often because it really flies. I bought Mobil one for my car, but because the local Chevy dealer is doing full service changes for 9.99, I can't see laying under the car anytime soon. It seemed like my Trans Am actually ran cooler and stronger with Mobil one...exclusive oil for the vette... must be something to it. Back to the sound system, if I understand, we can use the factory head as only a radio cd/ cassette deck and after that the signal generated from the head can be interuppted and enhanced through after market amps and speakers with out adverse sound and noise? What about a cd changer? My Sony head controlled the cd changer, but I could live with fm modulated if I had to. The skinny snow tires are the way to go. These fat tires do not like snow they remind me of some Goodyear Gatorbacks i ran a decade ago.
I'm averaging 22 MPG in mixed driving with 93 octane Mobil and whatever oil my Pontiac dealer uses. I figure I get the same 17/27 as ezrapon but do not consider this lousy. For a performer in this weight category, I feel this mileage is acceptable. Does anyone use Sonoco ultra 94 and achieve better results? How is your mileage dmckeown? I know you give your baby a nice drink of high octane every now and then.
I just leased a 2000 Pontiac Bonneville SSEI ; it is one month old with 600 miles on it (I think 19 miles when I picked it up).
Friday night (12/08) I was at the movies with a friend of mine. Moments after starting the car to leave it was determined that my car is on fire! It burnt most of the upper rear portion of the engine block area; the rear half of the intake manifold (or engine) shroud burnt away also. I’m afraid a great deal of that plastic/chemical smell is now entrenched in my interior. One of the firemen had told me, with a qualification he was not trying to be bias in any way, “they” will try to tell me anything but two things would be for sure. He said the car in all probability would never be the same electrically (something about heat traveling along wires) and the smell would always be there.
The reason I’m on here with this story is that I’m looking for someone that has had a similar incidence as mine and could give me some feedback as to the details of their experience.
Thanks in advance for any help.
P.S. I’m am posting this in a number of sedan areas to try and get as much response/help with this as I can, I apologize for any inconvenience it may cause.
your stereo guys are not up-to-date. I have spoken with the owner of Soundgate ( and a true audiophile) who has assured me that they make what we need to used the head and install our own amps and speakers. Go to the website, and email him. www.soundgate.com .
I get 20 mpg witha combinatin of city and highway. And as you can probably telll from the threads, I am not light on the throttle. I use Mobil 1 oil. Very happy with it. Better mileage. I am also getting ready to have the tranny flushed and Mobil 1 ATF put in there.
Last few weeks I've noticed a red 99 GTP that parks at my building here at work . Unlike the other GTP's that park here this one was modified , exhaust was obvious . So last Friday I left my card on it and asked him to call me . Today he did and we talked , he is running a 3.40 pulley, SLP CAI , 8mm taylor wires and NGK plugs , Autotrans Interceptor (modified) 180 T-Stat Casper FPR , RAT U-Bend , RAT 3" Cat-Back exhaust , Buick STB's TPSE , Crossover wrap and the Rat Heat Shield . I will go for a ride sometime to hear the exhaust and note any drone . He says there is a few other modified GTP's in this area of Xerox , I may have to watch out . There is two other 2000 SSEi's just at this small building and the one next door to mine , also 3 SE's . I envy you guy's that don't see that many around , you must stand out , I may contact the other SSEi owners and see if they are interested in performance ! Gas mileage , I'm getting about 19 mpg mixed highway town , but my foot likes to go to the floor a lot , I noticed as my car performs better with each level of mod , I get on it more . As for mpg related to pulley size , if you don't horse it , it gets about the same as stock . But if you have 30 to 65 more horses then stock and your using them ,well they got to eat , and guess what they eat ! I have noticed when I run 100 octane it gets 1.5 to 2 more mpg then the 94 I usually run .
Except for the occasional spotting, I hardly ever see another 2000 SSEi/SLE. The base SE is almost as rare. You would think that over the 15,000 miles I've driven over the last 6 months, I would have seen more. I'm glad I haven't. I really like it this way!
Merry x'mass snickle , the cardboard mock up is on it's way ! When you get it and look it over you can figure out if just making up a close copy (with some imp's I can tell you about) or go all the way for a clean sheet design . I also included the worthless instructions , I think they made the copies on a 200 dollar Radio Shack copier ! What FPR did you get , is it on yet? My neighbor with the red GTP said he went with the Casper unit because it is easier to adjust then the RAT unit . He says it really made a diff. , mostly at wot . This after the cat back and u-bend mods
Anybody know about this adjustment on the supercharger . I hear that there is a screw or screws that can be adjusted on our supercharger to bring the boost on quicker and at a higher level , almost sounds like a wast gate of sorts . I am trying to get the info needed on this from a guy who has done it on several GTP's
iT WOULD STAND TO REASON THAT ANY PUMP (THATS WHAT WE HAVE) WOULD HAVE A RELIEF VALVE OF SOME KIND. MOST RELIEF VALVES HAVE A FACTORY SETTING THAT IS BEGGING TO BE PLAYED WITH... AFTER THE PULLEY MOD, WE MIGHT HAVE WRUNG EVERY HORSE OUT OF THESE THINGS, BUT IT SOUNDS LIKE IF IT WORKS ON A GTP, IT WILL WORK ON THE FLAGSHIPS AS WELL. AM I A TRADITIONALIST OR DO REAR WHEEL BURN OUTS SEEM MORE APPROPRIATE? Sorry 'bout the caps... these -33 degree wind chills have me brain dead... they are heading for you east coast guys... be ready for some great burn outs and such!
I heard today that The General is going to discontinue the Oldsmobile nameplate. This will translate into more sales of Pontiacs, Buicks, Chevys, and Caddys. Those that want that "GM feeling" won't be able to get it in a new Olds anymore.
I got the casper unit. Have not had a chance to put it on. I hope to get it on this weekend.
As for the bypass valve, that is standard on an Eaton supercharger. Basically it is what allows us to get decent fuel economy even SC'd. I don;t know of an adjustment but it makes sense. Though tweaing it could have a big impact on mpg.
The first experimenting I did when I got my SSEi was with the Boost Bypass Valve. I don't think there is any gain to be had there.
First of all, this valve only has two positions - on or off.
Second, it doesn't regulate or govern boost in any way. It only disables boost in reverse, park, or under I think one other condition.
I got this information from the 2,000 page Helm manual. And, I have confirmed it in two different ways, which you can do at home without tools.
First, disconnect the valve and start the car. It will detonate the very instant you give it any gas at all, even in park. I believe the reason for this is that the boost climbs as soon as the RPMS do, and with no load at all the timing is so far advanced that the Knock Sensor can't possibly retard the timing enough to stop the preignition.
Second, leave the valve connected, and nail the throttle in Park, while watching your boost gauge. You won't see any boost at all because the boost bypass valve is doing it's thing.
It was a good idea though! If we keep being creative, eventually we'll figure out how to make our cars even more respectable...
I am a little stumped by the adjustable Fuel Pressure Regulator trend.
My Autotap shows Air/Fuel ratio to be virtually perfect at 14.7:1, until right up to full throttle. At full throttle, it drops immediately to ~11.5:1, and drops slowly the longer I stay on the gas. It bottoms out ~10.5:1.
So, I don't see where increasing the fuel pressure would buy me any additional power, at least until I 'fix' the exhaust system. If I'm right here, this explains why my previous attempt at spoofing the Intake Air Temperature Sensor had no measureable effect on performance - the engine already had plenty of fuel.
Now, let's pretend I fix the exhaust, and find the engine to be leaning out at full throttle - then I'll understand how increasing fuel pressure could make a serious horsepower improvement.
Anyone have any good input on this subject? Am I overlooking something here with my tendency to oversimplify everything (so I can pretend to understand)?
The best kept secret in forced induction is the little known bypass valve. This small valve, when properly installed between the supercharger and the air throttle body, allows the supercharger to become extremely efficient in terms of economy and parasitic power loss. Our M90 supercharger uses less than 1/3 of 1 HP at 60 MPH cruising. The bypass is operated by a vacuum actuator control unit that is normally closed. When vacuum is high (idle-cruising) the actuator opens the bypass valve, equalizing the vacuum pressure throughout the system. When boost is required (accelerating) the vacuum is decreased and the bypass valve instantly closes, causing pressure to increase into the cylinders. This equalized vacuum condition virtually eliminates the normal parasitic power loss of a forced induction system.
General consensus on the GP groups appears to be that the car runs lean at WOT, with pulley changes and exhaust changes.
I think that might be slightly inaccurate. I believe someone posted a detailed message indicating that it was not how much fuel was getting into the cylinder, but when. Something along the lines o the injectors were still open and injecting fuel after they should be. So basically fuel is getting wasted and not contibuting to power. Increase in pressure lets more fuel into the cylinder sooner in the injector cycle.
As for air/fuel ratio, I am not sure the autotap numbers are entirely accurate. I will have to check the numbers and my helm, but I think those numbers are more what the PCM thinks the air fuel ratio is, not what it truly is. The PCM has a hard time dealing with our increased boost.
Just some random thoughts. I will dig through helm and autotap. Also we shall see when I put the FPR in.
I'm 6 feet tall and am very comfortable with the seat bottom and pedal configuration. At first I was not as comfortable in the seat as I was in my '97 SSE, but after a short time the seat contoured to my body. I have no complaint on the pedal size and location. I do have a complaint regarding the quality of the leather. In a car in this price category it should be higher quality/softer. I also wish the seat back was rounded more.
Is this the new site we were told about around November 1st? Differences I see already are that you can't down load all messages at one time and when you log on it doesn't tell you if there are any new messages. L8_Apex, are you there? Do you have any comments for us? What else is different or better about this new site? I do like the new spell check.
I threw my s/c belt today. The car ran fine, just didn't have the nice neck snap the cold weather has given me. When I installed the 3.4 pulley, I used the factory belt as it only had 3000 miles on it. I guess I need to go to the smaller belt now. What is the brand and number of the next size down? Also when I installed this belt, I just applied hand pressure (no tools) on the tensioner to git the belt on. OK, now the stupid question. The smaller belt might need more than hand pressure... how do I relieve the belt tension pressure. This is the 4th time I've tried to post this, it keeps sending me to another page and does not post... here we go again!
I was looking at the sc today and wondered why the bolt end on the pulley shaft appears to soft material. Is this so it will be easy for a service man to tell if someone has tried to remove the pulley? Also any idea when we may be able to all get together?
A 3.4 pulley should use a stock belt. I do not kn ow the polycog or gatorback number for the stock. If yougo to the polycog site it will give you a cross reference. If you won;t a touch shorter, lose a 1/2 an inch and you should be fine.
i just got a 92 ssei and im lovin it, i bought it from an old guy so its immaculate. I got it after my 79 smokey and the bandit trans am got me in trouble and cause me a lot of stress. Im looking for a little more performance out of the bonneville. I need some tips on what to do first, im thinking exhaust, cool air intake, or pulleys. Any other easy or cheap suggestions?
Somebody told me that the 92 ssei's had a different engine that was built up more than the newer 3.8s because gm wasnt sure the engine could hold the supercharger. They also said that it was only put in the 92's and they are limited production cars. Anyone know if this is true?
The soft bolt on the end of the shaft is functional as only a breather it holds only itself on. LITEMUP... you have the 3800 series engine. The mid 90's brought on the 3800 series II engine. Most of the mods discussed here are exclusive to the series II engine. Most performance enhancements center around increasing boost with a smaller pulley ratio. I have not seen any of these improvement parts for the series I engine.
Comments
A buddy of mine said to keep the heat down in the engine bay, that i should remove the big plastic 3800 decorative cap. I got home from work the other day and pulled it off...MAN that thing was hot and holding in the heat...any suggestions/ideas on this subject.
I really like hearing the supercharger 'scream' now when I nail it. And the car will completely obliterate the tires from a standstill now...
Here are my mods to date: 2000 Dark Bronzemist Metallic SSEi, 18 x 8" Konig Villain wheels, P255/45ZR18 Michelin Pilot XGT Z4 tires, 1.25” Saner front and 1" rear sway bars, polyurethane front and rear frame mount and end link bushings, Thrasher Cold Air Induction System, 3.25" Thrasher supercharger pulley, 71.5” Dayco Poly Cog belt, 180 degree thermostat, Jacobs Electronics Ultra Coil Packs and 8.5mm. Energy Core Spark Plug Wires, NGK TR55VX spark plugs (gapped at .065"), Valentine One radar/laser detector
The fun has begun.
Exhaust - What goes in must come out.
FPR - Under WOT, I would expect you to be running pretty lean. I should have mine installed this week.
I'm a relatively new owner of a 2000 Bonneville SSEi (black), and must say I am enjoying the car immensely. I've had it about 2 months and have around 3500 miles on it, so I drive it a decent amount. And after driving an SUV for the past 5 years, this is like getting a crash course in how much fun a car can be to drive.
I do have a couple of questions, however. I see a lot of people posting about getting the K&N Filter, and was wondering two things. One, where is the best place to get one? I would like to order online, and was wondering who might have the best price. Second, at the couple of places I've looked so far, they don't list a filter for the 2000 SSEi, so is there a certain one I need?
Thanks for any assistance!
had a better deal.
Thanks again.
Also another question for those who have had experience with the SSEi in the snow, are the stock tires good for this or is there another set I should be looking at now that winter is approaching. We got our first real snow the other day, and even with the trac control on, things seemed pretty slippery. Definitely need to learn to feather the throttle better when taking off in the snow.
Doug or Scott,
Any snow? Doug, I know you don't drive the new one much in bad weather, how about you scott?
What are your 0 to 60 times. Did you use autotap at each mod to measure the change? What have you blown away on the road. Have you been blown away and by what?
I have done the K&N filter and am awaiting the pulley party which we are trying to arrange here in the Northeast.
Eager to hear more of your comments
1. Because of the type of electrical system that GM uses in our cars ( digital series buss ground), and because of more than just music that is processed thru the "head/amp" sytem of our cars, as well as the BOSE 1 amp deal, it is impossible to REPLACE the head, and not suffer serious electrical problems.
2. There is available, if you must have an aftermarket head unit, a cable/ harness which allows the head unit to remain in circuit, but allows a new head unit to go in the dash hole. ( The old head must be relocated behind the dash.) Since actuall "performance" gains in CD/Casstte/FM/AM will be negligable, this will be for cosmetic, and "feature" issues. The CD pre-amp signal from the " Bose" unit is for all intents and purposes the same as from an aftermarket unit.
3. Most "hearable" change will be realized from a change in speakers and amp. This is realativly easy, especially if you leave the oem head unit in place. The up side to doing this is the electrical system of the car, and things like door chimes, remote radio controls, on-star, etc. remain unaffected.
4. The amp that drives the speakers is located behind the rear drivers side back seat. This is replaced by an amp of your choice and must be connected to the head leads with a module from SOUNDGATE which allows the head unit to think it is still talking to the old amp. After this, the sky is the limit speaker wise. A six channel amp would work fine.
Long highway trips with NO city driving get me 24.3 MPG max. Is this normal? I have a 3.5" pulley, but have not installed it yet. Will this adversly affect MPG?
Is anyone using synthetic oil? If so, any comments?
Friday night (12/08) I was at the movies with a friend of mine. Moments after starting the car to leave it was determined that my car is on fire! It burnt most of the upper rear portion of the engine block area; the rear half of the intake manifold (or engine) shroud burnt away also. I’m afraid a great deal of that plastic/chemical smell is now entrenched in my interior. One of the firemen had told me, with a qualification he was not trying to be bias in any way, “they” will try to tell me anything but two things would be for sure. He said the car in all probability would never be the same electrically (something about heat traveling along wires) and the smell would always be there.
The reason I’m on here with this story is that I’m looking for someone that has had a similar incidence as mine and could give me some feedback as to the details of their experience.
Thanks in advance for any help.
P.S. I’m am posting this in a number of sedan areas to try and get as much response/help with this as I can, I apologize for any inconvenience it may cause.
http://www.luckyjdr.homestead.com/ls1impala.html
I will go for a ride sometime to hear the exhaust and note any drone . He says there is a few other modified GTP's in this area of Xerox , I may have to watch out . There is two other 2000 SSEi's just at this small building and the one next door to mine , also 3 SE's . I envy you guy's that don't see that many around , you must stand out , I may contact the other SSEi owners and see if they are interested in performance !
Gas mileage , I'm getting about 19 mpg mixed highway town , but my foot likes to go to the floor a lot , I noticed as my car performs better with each level of mod , I get on it more . As for mpg related to pulley size , if you don't horse it , it gets about the same as stock . But if you have 30 to 65 more horses then stock and your using them ,well they got to eat , and guess what they eat ! I have noticed when I run 100 octane it gets 1.5 to 2 more mpg then the 94 I usually run .
What FPR did you get , is it on yet? My neighbor with the red GTP said he went with the Casper unit because it is easier to adjust then the RAT unit .
He says it really made a diff. , mostly at wot . This after the cat back and u-bend mods
As for the bypass valve, that is standard on an Eaton supercharger. Basically it is what allows us to get decent fuel economy even SC'd. I don;t know of an adjustment but it makes sense. Though tweaing it could have a big impact on mpg.
Personally I think they designed this care for those 5'-10" and under.
2000 ssei owner
First of all, this valve only has two positions - on or off.
Second, it doesn't regulate or govern boost in any way. It only disables boost in reverse, park, or under I think one other condition.
I got this information from the 2,000 page Helm manual. And, I have confirmed it in two different ways, which you can do at home without tools.
First, disconnect the valve and start the car. It will detonate the very instant you give it any gas at all, even in park. I believe the reason for this is that the boost climbs as soon as the RPMS do, and with no load at all the timing is so far advanced that the Knock Sensor can't possibly retard the timing enough to stop the preignition.
Second, leave the valve connected, and nail the throttle in Park, while watching your boost gauge. You won't see any boost at all because the boost bypass valve is doing it's thing.
It was a good idea though! If we keep being creative, eventually we'll figure out how to make our cars even more respectable...
My Autotap shows Air/Fuel ratio to be virtually perfect at 14.7:1, until right up to full throttle. At full throttle, it drops immediately to ~11.5:1, and drops slowly the longer I stay on the gas. It bottoms out ~10.5:1.
So, I don't see where increasing the fuel pressure would buy me any additional power, at least until I 'fix' the exhaust system. If I'm right here, this explains why my previous attempt at spoofing the Intake Air Temperature Sensor had no measureable effect on performance - the engine already had plenty of fuel.
Now, let's pretend I fix the exhaust, and find the engine to be leaning out at full throttle - then I'll understand how increasing fuel pressure could make a serious horsepower improvement.
Anyone have any good input on this subject? Am I overlooking something here with my tendency to oversimplify everything (so I can pretend to understand)?
The best kept secret in forced induction is the little known bypass valve. This small valve, when properly installed between the supercharger and the air throttle body, allows the supercharger to become extremely efficient in terms of economy and parasitic power loss. Our M90 supercharger uses less than 1/3 of 1 HP at 60 MPH cruising. The bypass is operated by a vacuum actuator control unit that is normally closed. When vacuum is high (idle-cruising) the actuator opens the bypass valve, equalizing the vacuum pressure throughout the system. When boost is required (accelerating) the vacuum is decreased and the bypass valve instantly closes, causing pressure to increase into the cylinders. This equalized vacuum condition virtually eliminates the normal parasitic power loss of a forced induction system.
General consensus on the GP groups appears to be that the car runs lean at WOT, with pulley changes and exhaust changes.
I think that might be slightly inaccurate. I believe someone posted a detailed message indicating that it was not how much fuel was getting into the cylinder, but when. Something along the lines o the injectors were still open and injecting fuel after they should be. So basically fuel is getting wasted and not contibuting to power. Increase in pressure lets more fuel into the cylinder sooner in the injector cycle.
As for air/fuel ratio, I am not sure the autotap numbers are entirely accurate. I will have to check the numbers and my helm, but I think those numbers are more what the PCM thinks the air fuel ratio is, not what it truly is. The PCM has a hard time dealing with our increased boost.
Just some random thoughts. I will dig through helm and autotap. Also we shall see when I put the FPR in.
Also any idea when we may be able to all get together?