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Pontiac Bonneville



  • dmckeowndmckeown Posts: 107
    At this point I still have a was to go before I try to post times at a track . My 2000 SSEi is about 3850 lbs , 400 more then my 93 Bonnie . 0 - 60 times will suffer in this car because of high gear ratio and only one front tire pulling for you. I time my car a bit under 7 seconds 0-60 . But once above 20 mph I can floor it and then it really goes . The scary part is that it really comes on after 70mph !
    What are the Grand Prix GTP's posting at your track ? I saw in the Grand Prix site one posted an 11 sec quarter mile!!
  • well 11 seconds is nuts some Impalas run in the 11s and pretty soon they will be in the 10s too but that is extensive mods.

    The GTPs around here seem to be running low to mid 14s and that is with sticky tires and pulley and exhaust work.

    I'm going to the track Friday to see if I can't break the 14s. Talk about heavy my car is 4371 lbs... yikes thank god I have some real torque. I'm eager to put 3.73 gears in but then I'll need some better tires and lower control arms.

    The best thing about the Impala is that there is a plethora of aftermarket things for the car. There are people that autocross the Impala with numbers that would humble a stock Corvette.

    What does a stock Bonne run these days mid 15s I think? I thought I saw a test in the high 15s I guess its not as fast with the added weight... stock GTPs run about 15 flat.
  • intense01intense01 Posts: 107
    OK. I've been thinking about all this IAT Spoof stuff on the Grand Prix list. There are three possible ways to connect a spoofing resistor - in series, in parallel, or instead of the IAT sensor.

    Someone said that SLP's 'product' is a 5 ohm resistor. According to the Helm manual, that would make the PCM set a code for the temperature being out of range (>212 degrees Fahrenheit) if it replaced, or was in parallel with the IAT sensor. In series, this value of resistor would have no measurable affect (less than one degree difference at all points).

    Someone else said that SLP's 'product' is an 8.12k-ohm resistor. This is more believeable because it could have a positive impact. According to the Helm manual, that would make the PCM see a reading 20 to 80 degrees colder (depending on temperature) than actual, if wired in series with the IAT sensor. If wired in parallel, this resistor would send a signal representing a higher than actual temperature (not what we want). If wired to replace the IAT sensor, this resistor would send a constant signal somewhere between 34 and 39 degrees Fahrenheit. This last option is my best guess on what SLP has done, although I have not seen their product.

    I myself designed what I thought was a cool little circuit recently. I connected a microswitch to my throttle. Under full throttle, the microswitch would trip a small relay. The relay would then bypass the IAT, and substitute a 52.7k-ohm resistor. This resistor value made the PCM see a temperature of -22 degrees Fahrenheit, which is about as cold as we can go without setting a code. Bottom line was that I could not detect any measurable performance difference.

    Does anyone have any additional knowledge of IAT spoofing that I may have overlooked? And, does anyone have any tried and true method of getting better performance in this manner?

    Scott - 2000 Dark Bronzemist Metallic SSEi, 18 x 8" Konig Villain wheels, P255/45ZR18 Michelin XGT Z4 Pilot tires, 1.25" front sway bar, 1" rear sway bar, polyurethane frame mount and end link bushings, 3.25" supercharger pulley, 180 degree thermostat, NGK TR55VX spark plugs (gapped at .055")
  • snicklesnickle Posts: 147
    The purpose of an IAT spoof or any other IAT mod, as I understand, is to richen the fuel mixture as our mod'd cars tend to run lean. I have a philosophical objection to misinforming computers. I understand the need, since we can't reprogram, but...

    Off the soap box. IAT spoofing is really aimed at WOT performance. It will only be effective if the fuel system can inject enough fuel to richen up the mixture. Too much is almost as bad as not enough.

    I think either a small resistor or repositon the iat to a cooler location (fender wall or front of CAI) would benefit daily driving. Don't want it too rich.

    As for the micro switch, I think the sudden change will not be recieved well by the PCM. really need to phase in the tempature change prior to going WOT.

    How about a small inline resistor and then a switch to bybass the sensor and the resistor with a 50 kohm or so when you figure to be going wot alot. Would let you give the PCM time to adjust.

    As far as not seeing a performance increase, I suspect that is due to the fact you are not running as lean as a lot of the GTPs. Primarily caused by your stock intake. You are not getting as much air as the average mod'd GTP or Doug's SSEi.

    Quick test since cooler weather is here. Get the re-0870 filter and the cone filter kit from the gp store. Total cost about $100. Reset the PCM and train it for a tank. Then try the manuever. Though just changing to the cone will be an instant improvement, when the engine is cool.

    We both need a CAI. I need to finish building mine or breakdown and buy the thrasher kit to mod like Doug.
  • snicklesnickle Posts: 147
    Finding a way to spoof the MAF might help more. That is what RAT does in their stage II unit, ported and recalibrate to adjust for the turbulence.

    Though we can probably do most of the same thing by just by using a fuel pressure riser to boost the amount of fuel being fed to the cylinder and letting the PCM back it off.
  • dmckeowndmckeown Posts: 107
    After sending intense the pictures of my Thrasher cold air induction he had some questions. One in particular has got me thinking , that of adding an additional inlet hose to the passenger side of CAI box and running it down to a scoop under driver side of air dam . At that point I could resume sealing off any suspect hot air inlet areas resting assured I had provided full air flow with the cold air ducting and not suffer lose of power as I did in earlier experment with duct tape . I might go to hardware store and look at some PVC pipe and fittings for duct , but what about the actual scoop ? I would put a screen filter on the scoop to duct junction to keep some debris out and maybe a finer screen up at the opening into box . Even if scoop became plugged I still have two stock opening left . And when moving it should have a ram effect with proper size scoop and ducting and assure cold air
  • snicklesnickle Posts: 147
    An additional source of air would help. I don;t think you will get much ram air effect. Even a RAM air hood does not really ramthe air. Just give a well ventilated opening. I worry about the additional dust with a low scoop. I company in Hawaii makes systems like that. I'll find the link.
  • I just bought a 1996 Pontiac Bonneville SE with 35,000 miles and was wondering how reliable this car has been. Panchoman
  • smfransmfran Posts: 432
    I had a '94 and '97 and both were very reliable. The only time the '94 let me down was my own fault. The battery warning light came on and I ignored it. Eventually the car died due to the alternator. If I had replaced the battery, this would not of happened. Good luck.
  • dmckeowndmckeown Posts: 107
    I have a 93 Bonneville with 110 k which has been very good . Do you know the history of car , service records , how it was driven and if it was in an accident , these things can be a factor . Best luck with a car well maintained and highway driven and never in a collision . If car is good you should expect reasonably trouble free till 75 k or so when you will be looking at struts and maybe that alternator problem , although mine is orig. at 110k
  • dmckeowndmckeown Posts: 107
    Good morning , I replaced my battery at about 75 k when I noticed slow starting in cold weather , maybe that saved my alternator . Did you see the post on Bonneville maintenance about battery terminal screw length , interesting
  • okkidokkid Posts: 4
    Do any of you know about the odometer settings. I t seems as if my car is racking up the miles to much. I can drive what I know is a 50 mile round trip and my car will register 65 miles. The dealer says there is no problem with my car but I know that there is.
  • ymandjymandj Posts: 10
    I own 1996 Bonneville with 45K on it. Recently I was driving, stopped at a store and when I came back I couldn't start. Dead silence. I started from a booster. Voltmeter showed appr. 13V. Went to my repair shop. They change battery and alternator. It seems to fix the problem, but since then when I switch gears to Reverse, voltage goes down to red zone (11V?), light (if it is dark outside) almost goes off and then voltage slowly goes back up to 12-13V. Is it normal? Is it short somewhere? My mechanic seems puzzled with it.
  • smfransmfran Posts: 432
    Your advice to ponchoman was excellent. I believe I've read posts from you like this before. Knowing history, etc. is definitely the key when considering a used car.
    I treat my cars very well and keep meticulous records. It turns out though that this maintaining of records only helps ME. I can review situations (like alternator experience) and expenditures, but when I go to trade it in, which is what I've always ended up doing, the dealer couldn't care less about my records. This is probably due to two reasons:
    1)Dealers don't get involved in giving maintenance history to buyers of used cars.
    2)By the time I'm done with my cars, they have high mileage only worthy of the auction; not the dealer's lot.
  • snicklesnickle Posts: 147
    I talked to John at Saner. He was waiting to hear your review before he sent me an email. After driving it or a few days, what do you think?

    How does the car steer? over, under neutral?

    Any noticeable ride effect?
  • snicklesnickle Posts: 147
    Your best bet is to find a defined mile stretch and confirm how much teh odometer is off. I am assuming you have made no mods. A 50 mile round trip registering 65 miles implies a 30% inaccuracy. Should be easy to prove. Find a set of mile markers around the dealer. Drive it with your car and then a friends car compare teh readings to the .1 mile. Your friend should show 1.0 miles you 1.3. If that is the case, duplicate the test with the service manager comparing your car and his or one off the lot.
  • snicklesnickle Posts: 147
    Check out
  • Thanks for the information on potential alternator problems with my 96 Bonneville. It's something I will keep an eye on. I don't have a history since I bought it from a dealer, but I checked with LemonCheck and the car was bought in Illinois and registered in Nevada with only 19K in 1998, so I think it may have been owned by a couple retiring to Las Vegas. I just did my first mileage check and got 24.5 mpg with a mix of highway/local driving. I'm very pleased especially with such a big car. The car runs VERY smooth. I love the Magnasteer steering. I wish it had a computer and the stock FM/CD radio sounds just average, but I do like the radio controls on the steering wheel. This is my first GM car in 15 years after driving mostly Chrysler products.
  • ezraponezrapon Posts: 348
    I just read an article by Dave Hill, the head of development for the Corvette. It was in one of the recent car mags... anyway, he was asked why the vette gauges swing from zero to 100% back to zero, then to the proper setting upon each start up. Hill said for no other reason than it looks cool. I thought damn, that is cool! I went out to my SSEi for work this morning and watched my gauges... I smiled and thought to myself... damn, that really is cool!!!!
  • intense01intense01 Posts: 107
    Snickle - I'm 1,000 miles into my new front sway bar already. Very happy with the balance front to rear. 1.25" front, 1" rear - polyurethane bushings all around.

    No affect on the straight line ride. Significant improvement to transient response, and overall cornering capability (with the traction control turned off), as with the rear bar. This modification is an excellent value for the money.
  • dmckeowndmckeown Posts: 107
    Go out and check your battery terminals for fit . By this I mean grab a hold of one with your hand and apply a twisting motion , they should not turn . There was a post indicating some Bonnevilles had terminal screws too long and they would bottom out in the battery terminal before fully tighting surface of battery to wire . This of coarse caused all sorts of battery and alternator problems . The fix was to back screws out of wire and put a washer under head of screw . Just a thought and easy to do . Doug
  • dmckeowndmckeown Posts: 107
    Have you every sold your cars yourself through want ads ? I know it can be a pain , but with the way you maintain cars people tend to trust an individual selling and pay a fare price . You get much more then any dealer will give you even with tax diff. and every body is happy (except dealer) . I have sold many over 125 k cars this way . Also , when I was looking at 2000 Grand Prix for my wife I saw the ad for the 99 Grand Prix I ended up getting her , so I also will buy from a private owner and I got a great deal . It is harder to sell cars for over $10,000 privately I think
  • smfransmfran Posts: 432
    One of the "stupid things" about Pontiac and specifically the Bonneville that have kept me loyal, is the dashboard red/orange lighting and the gauges swing. It is one of the elements that makes Pontiac different from the mainstream. To my knowledge, Bonneville has the highest percentage of repeat owners. Not too stupid is it?!?!:)
  • i have a 2000 bonny ssei i just put on second gen. pully 3.4 and ravin mufflers computer display reads exp 144 ?? and low tire presure ?? i have on order set of 8.5 mm spark wires and a second gen. msd ignition box any body try box yet ? any computer changes needed or problems.
  • ezraponezrapon Posts: 348
    No help on the computer problems, but how did the mufflers work out... sound... performance gains? Did you remove the resonator? I'm thinking about the Ravin mufflers myself, but don't know what to do with the resonator. My computer loses its compass memory... they have replaced the module and it still won't stay right. The chiming and orders to recalibrate are real annoying.
  • ravins sound good cant tell performance with new pully had muffs put on at midas res. still on am going back for new pipe guy at shop wanted to change but didnt have my ok i live 4 hrs away from shop i just got e mail from saner on anti sway bar so i should be going back 1-11/2 weeks ill post agin then.
  • snicklesnickle Posts: 147
    Are you ordering the 1" rear, 1.25" front or both?

    Intense has both with 18" wheels. I have the rear and just ordered the front.
  • snicklesnickle Posts: 147
    I have an appointment for Thursday to put the flowmaster on. I you don't hear from me after that, you knmow they were too loud and my wife killed me for the insurance money.
  • 1" rear urethane front end links first i heard of front bar let me know how that works out i got the tire upgrade but still only 17"
  • smfransmfran Posts: 432
    I'm thinking of painting my exhaust tips with chrome spray paint. What do you think of the idea?
This discussion has been closed.