no ac after 140mph???

[AZhitman]

Yep - The front end seemed to VISIBLY rise around 135. Not sure it this is due to some aerodynamic phenomena, the lack of a belly pan (still haven't replaced it), or just a missed perception on my part.

At any rate, the rear felt well-planted and the car was STILL making power, it just felt light in the nose.

I concur, I'd give a tidy sum for an hour's worth of track time at Phoenix Int'l Raceway's banked oval.

[louiegz]

175 Yea right. Keep it up with your cheap plenum job but don't tell fish stories here.

[squeefoo]

About 14 years ago I worked with an engineer, Joe Frank, whose brother is/was on the board for Porsche, Audi , VW. Joe was younger than his brother by quite a few years, and bought a prototype from them via his brother. This was a Beetle convertible with a Porsche flat six installed. Joe takes this thing on the autobahn and says "Let's ze vaht ze hell this 'ting ist gonna do" somewhere way up there in Kilometers the steering gets real light and becomes nonresponsive to input (can you say pant load?). After that he was self restricted to secondaries. Joe finally figured out the ribbing from the convertible top was creating lift combined with the light front end.

[maxnix]

The Y33's are limited too, I am unsure about the 2k2+'s to which mph they are limited to but they are also limited.

Fred..

I believe all F50 are limited to 150 mph, much higher than say a 745i at 135 mph.

[Rex]

Okay, I'll finally "comment" on this as I believe the viability of 140, but greatly doubt (been wrong before) the 170+.

I've reached 130-ish in my car, which is no glowing example of pristine maintenance, nor "mod-loaded" beast, and have to say it was much easier than expected. This may have to do with the shift point for 3rd, but I'm purely speculating.

So, what I'm saying with this is - I can see 140 being achieved in a good/better running Q, with sufficient, but not overly lengthy roadway, but CANNOT imagine/believe anyone getting near 170+ without changing thier rear gearing in the opposite direction. If someone went to a 2.90 or higher (numerically lower) gear, there is a chance, assuming JWT to remove limit, they could go farther, but this would require a greater length of roadway.

There, my 2 cents have been deposited.

[Rex]

Anyone recall what rear gearing was in the Salt Flats Q, that went for a land speed record?

I realize it wasn't a G50, and was purpose built. But if someone is simply after high speed bragging rights, it would be a good blueprint.

[rsiwicki]

170 is pretty damn hard to attain in a true SPORTS car let alone a Q45. My car never saw above 120 for the 6 years I have owned becuase it took way too long for it to get up there in speed and I was afraid of a ticket. Recently due to all the mods...now 135 has gone from just another day dream to a reality that in itself still has me smiling how quick my car is. I think it must be from the lack of CAT and the headers as my car seems to never loose any significant power after 6,000 rpms...it just keeps pulling all the way to redline. The fatest I have had it up to was between 145-150, but I don't remeber the rpms that I was running. I guess I will have get the old video camera out and do some taping.....the 3-4 shift at 135mph is such a nice sound at those speeds

btw...as happy as I am with my freeway power, I would still love to get a 0-60 time of 6.0 flat vs. my 6.7secs as estimated by Q45tech based on my 1/4 runs...
Modified by rsiwicki at 5:06 PM 9/13/2004

[Jesda]

I got a 3.0L Mazda 929 up to 130mph (according to speedometer). I had to get halfway across Washington state to do it, and it was mostly down hill from the mountains.

I was younger and stupid back then, doing it on cheap old worn tires in the middle of the night on the interstate. A deer could've easily killed me. And then I heard a noise... my muffler was dragging on the pavement. Pulled into a rest area and coat hanger fixed that right up.

Shame on me!

[PoorManQ45]

I'll step aside while you retract your error.

I will retract the 175+mph I gave. But, I am dead serious about having had the speedometer maxed out. That would equal 160+mph.

I would bet the title of my pristine and perfectly-maintained Q against you exceeding 155 (much less 170) in your Q. Ever.

You serious? When I get my plenum back on in a few days, I will video tape of a top speed run. Would this satisfy you guys?

I have seen 140, once, with the proper tires, with no extra crap in the car, and in perfect mechanical condition, and it's a scary place. The lifting of the nose, even with a 1.2" drop, was enough to convince me that the car is best kept at/under 135.

My tires are about 1.5 year old. Haven't been balanced for 1 year. I've never had a problem with them.

I have never experienced any nose lifting before.

How do I find out when my car was actually made. And what number it is?

[Rex]

There should be a sticker in the drivers door jamb. It will list a few pieces of info, most noticably the gross vehicle weight and the production date.

[PoorManQ45]

thanks, I'll check there and get the info.

[PoorManQ45]

the production date is 8/91 (when was production started and when did it end?)

Gross vehicle weight 5027

[pito11213]

my production date is in 89.

[Rex]

the production date is 8/91 (when was production started and when did it end?)

Gross vehicle weight 5027

That would amke your car most likely a 92 model year, and according to "rumors" the only Q's without the speed limiter were early 1990's.

[Jesda]

The optimistic speedometer, yet again. Over 100mph accuracy flies out the window. You probably hit 135-140.

[rsiwicki]

don't need the speedo to know when you are at 135.....3-4 shift happens at 135mph when all else is in specs (tires, sensors, etc)....after 135mph would be somewhat in question

[Rex]

So I got close, as I was near redline (just under 6,500) in 3rd, but backed out as my point had been made .

[maxnix]

I've reached 130-ish in my car.

Hey, Rex, help an old guy with Alzheimers and tell us what year your G50 is in your profile, please.

Hey, wait a minute, we lost that data!
Modified by maxnix at 12:31 AM 9/14/2004

[Rex]

Yeah , I'm gonna guess when we get "skins" that type of stuff may come back.

Mine's a 94, you know the slightly slower years. I say that both tongue in cheek and knowing the earlier years are faster, even if the motor wasn't stronger & I believe it was, the lighter weight windows and such would contribute to a lighter/faster car.

Mine should be very close to rsiwicki's before he started modding.

[1992Q45A]

http://www.q45.org/cd1995comparison/Page%209.JPG

1995 Q45T

0-60 7.91/4 [email protected]

[1992Q45A]

During the 1991 International Race of Champions, Geoff Brabham tested his bone stock new Q on the the high banks of Talladega Superspeedway. He reached 150, and said he could have gone faster, but didn't want to because the car had less then 1,000 miles..

He wanted to baby it

[AZhitman]

During the 1991 International Race of Champions, Geoff Brabham tested his bone stock new Q on the the high banks of Talladega Superspeedway. He reached 150, and said he could have gone faster, but didn't want to because the car had less then 1,000 miles..

He wanted to baby it

Chicken-****.

[rahiel aziz]

i haven't posted here in long time but i always check nico few times in a week.i see this topic keep coming back about early Q's top end.i stopped posting speeding stories because dennis mention it can cause some legal issues.i have 91 Q production date 8/90.few times hit 160mph in past without any problem.i am not trying encrouge poormanQ here but thats what my speedo read .this was before i put jwt ecu/tcu.Q has very tall 3rd gear i can take upto 150mph in 3rd. there used to be a silent member on this board who got clocked doing 170+mph 0r 180mph in flourida it was posted on originalnico board as b.a.d Q article when speeddoctor(rex) was runnign it.that member had to spend thousnads on lawyers fee to stay out of jail.he was running jwt ecu and straight pipes.so hitman don't put ur title on line those early Q's might surprise u the way i surprise lots of new cars with their speedlimited at 130-150 e.g ls430,bmw 745i

[C-Kwik]

wow!!! I can't believe all this excitment.

greg....just curious as to why you would be feeling a "lift" in the nose of your car as I am thinking that you should be feeling the lift from the rear of your car. From my limited high speed driving experiences and limited knowledge from car mags...you should being feeling a lift from the rear of the car. The spoiliers on the rear of cars are to keep the back end down and more stable. I could easily be wrong but I would like to know if what I am assuming/read to be true that you should feel a rearend lift before any front lift from high speed driving...I have felt a rearend lift before where the front was glued down, but the rear felt really light and a tad wiggly, but not on my Q...it was my mom's car that I was driving in high school.

I have only gone to above 135 about 10 times and all 10 times being since I got my car all modded. And above 140 has only been 3 times to about 145 and I just so happened to notice the AC went out each time and just started blowing warm air. I would love to find a road to just cruise at 140mph or so to get a true feel for the car.

Consider the reasons for lift:

http://mb-soft.com/public2/lift.html

If you look at the profile of a car from it's side, you'll find the bottom is relatively flat while the top has a large hump. The air has to travel faster over the top of the car to try and catch up to the air going under the car ausing a low pressure area above the car. Where this occurs over the car is dependent on a lot of factors. Bernoulli's effect is an issue here. The reaction lift also described in the above link I think has some relevance. Not as much from a standpoint of angle of attack, but from one of cramming air under the car. Not all air will go over the car. In fact a lot will still go under the car. And this high pressure area will probably be greatest at the front of the car. Splitters can be effective in seperating the air at the bottom of the front bumper so that the most of the air hitting the front of the car will be forced to go over the top. While the Bernoulli effect may be increased, I think cramming more air under the car will have a larger effect on lift. Add in some ground effects and perhaps force a slight vacuum under the car and you can reduce life and perhaps cause downforce at higher speeds.

[PoorManQ45]

i haven't posted here in long time but i always check nico few times in a week.i see this topic keep coming back about early Q's top end.i stopped posting speeding stories because dennis mention it can cause some legal issues.i have 91 Q production date 8/90.few times hit 160mph in past without any problem.i am not trying encrouge poormanQ here but thats what my speedo read .this was before i put jwt ecu/tcu.Q has very tall 3rd gear i can take upto 150mph in 3rd. there used to be a silent member on this board who got clocked doing 170+mph 0r 180mph in flourida it was posted on originalnico board as b.a.d Q article when speeddoctor(rex) was runnign it.that member had to spend thousnads on lawyers fee to stay out of jail.he was running jwt ecu and straight pipes.so hitman don't put ur title on line those early Q's might surprise u the way i surprise lots of new cars with their speedlimited at 130-150 e.g ls430,bmw 745i

So, I'm not completely crazy, yet. There you have it, testamony from another early Q45 owner. Will that satisfy you a little? Or do you want me to make a video of a top speed run?

[pito11213]

i would love video just because there isnt much available of the Q just letting loose.

[AZhitman]

My offer stands.

Your Q is NOT an early 90 production model, it is speed-governed, and... well, there's no need to beat a dead horse.

p.s. I'd rather see a picture of the underside of a valve cover / top of the head.

[HeavyDuty]

I spent hours on a long post last night, then just saved it & didn't post.

My JWT ECU 91 has seen the topside of 140, maybe a little higher, but I know the speedo is inaccurate way up there.

My car walked a 89> Fox 5.0 on a four lane in a death match from 120 until I had enough on him to get out of it, perhaps two lengths. Those cars are capable of an honest 143 mph stock.

Please don't attempt a video driving at those speeds. We don't want to read about your latest effort to prove yourself. (Latest as opposed to most recent, read between the lines)

I'm the fool for engaging this in the first place.

[maxnix]

I can't help but laugh evertime someone says something to the tune of, "Leave it alone, Infiniti designed it that way. They spent millions of dollars on research to find the best way. If Infiniti made it that way, it is as close to perfect as possible."

And you received your BSME from where? And your résumé includes what projects in which automotive manufacturer's engineering departments?

Maybe you should apply for a job there. I am sure Nissan HR needs a good laugh today.

[PoorManQ45]

My signiature is meant to be funny.

Everytime I ask if I could/should change something on the Q45, I usually get the same responses. And they usually say the same thing as my signiture