Spanked by an 2004 Lincoln Navigator

[rover3l]

The shame of it. Here I was sitting at a set of lights when this apparently stock Navigator pulls up alongside me. When the lights changed to Green I floored it and the Navigator left me for dead. There was no room before the next junnction to catch up with him. I think the problem is my car rather than anything special with the Navigator. When I floor the throttle it seems to hold back and gently build up the revs. When it finally get ups to 4000rpm it then takes off like a bat out of he**. On the highway at normal speeds it has great acceleration and will kick down and surge ahead very easily. Any thoughts?

Note I have a new fuel pump 12 months old and fuel filter.

[rsiwicki]

I had this past Spring a ML430 leave me in the dust as we were both pulling/merging onto I-95. I about $hit my pants as how fast the damn thing pulled away from me and was so surprised that when I finally caught up to it that it was not the AMG version. 13+ years of new technology no matter how great are cars still are is tough to keep up with.

[Q45tech]

An unoptimized for zero to 30 or 60mph transmission often doesn't produce satisfactory results on the street! Just in the 55-85 range.

Same with a 32 valve vs a 24 valve vs 16 valve V8 with low rpm torque peaks............once you are a second behind [44 feet] at 30 mph, hard to make it up!

Everyone knows not to street drag a Q from a stop don't they.......at least not without nitrous.

[rover3l]

Everyone but me!!!

If I understand your comment, it is normal for a Q45 to perform like this from a stop?. The Navigator is also only 4 speed and similar horse power and a lot more weight than the Q

[rsiwicki]

my Q45 is still ohh so slow from 0-60 @ 6.7 secs even after all my mods and I am doing the 1/4 in 14.6 which is one of the fastest documented times...the Q is just not fast on the street for stop light races hence the need for a 4.08 rearend, but even that does not close the gap all that much. The Q has its torque peak around 4,000rpms so that is why you feel the rush and it takes the car a while to hit 4,000rpms from a dead stop.

[rover3l]

Is there anything to be gained by manually selecting and holding 1st from a standing start.

Does anyone know how it compares to rival cars such as a BMW 740 or Merc E400 of the same vintage as presumambly they also have highly tuned high reving small displacement V8's

[pito11213]

I am a witness of there being a huge difference of manual selecting gears. You get so much more control of the car. That is actually the only way to really win with a Q. These cars are heavy and big and when a bmw sees one fly by them while they have the pedal pushed down they have nothink but anger in their face.

[rsiwicki]

manually holding gears past redline is good only if you have a JWT ECU because the OEM ECU cuts off the power after 7,000rpms....just try it....hold it in 1st and punch it and then a little past 7,000rpms the engine dies as the fuel is shut off...I tried this several times in my Q and the fuel was shut off every time. The holding of the gears for a few extra hundred rpms will improve your 1/4 ET's hence the JWT TCU that gives you a 7,300 redline limit

[elwesso]

As you can see in my sig, it is marginally helpful...

The JWT is cool, its really neat to see the needle dip way into the "redzone"

[pito11213]

I'm sorry but 7000 rpm is just fine for me. I dont want to go into the red zone...that is one thing I dont want to mess with. I mean how many cars out there even rev up to 7000. I dont want to spend that much money on 300 rpm and the possibility of killing my motor.

[Q45tech]

OEM redline is 6,900 rpm.I can assure you 7300 rpm is quite safe [assuming you don't hold it there] considering the Q short stroke [3.256"] if oil was changed since new at the correct 90 day intervals.I am celebrating my 10th running year with a 7,300 rpm redline and high shift trimode TCU to match........[over 220,000 miles of use] since 1994 on the 268,000 mile 90Q.

Extra 400 rpm is 400/74.0= 5.4 mph in 2nd gear on 90-93Q differnce between 93 mph and 97 mph in quarter mile.......[not wasting 0.8 seconds shifting when you can still be accelerating].

[97Q45t]

How on earth could a Navigator out accelarate your Q? Edmunds tested one 4WD with 9.9s 0-60 and 17.4s 1/4mile. My friend has a '04 Navigator RWD and my '97 dances around it anytime. How on earth?

[rover3l]

I agree, but I said something stronger than "how on earth" at the time it happened.

This thread though seems to be suggesting that in the 0 - 30 range which is where it spanked me, the Q45 may be slow. Whether it is slower than a Navi is another question. My first thought was that I have a problem with something such as knock sensors etc.

[pito11213]

I still dont see how a Navi beat you. It just doesn't sound like a regular thing. Did you leave it in drive or did you shift down? I dont use the manual shift to hold gears I use it to have control of the car. Stick shift is the only way to race on turns IMO. I see the benefits of the TCU and ECU. Could someone list the prices of each. I am sure they are high though.

[QShip]

I had the same problem. I raced my sister in her Aviator and could not pull from her until I hit 3k.

It won't happen again...

next time I'll use my Titan.

[rsiwicki]

JWT ECU $650JWT TCU $450

The Q also has a really nasty dead spot from 30mph till 45mph as it will not downshift into first gear after 30mph unless you manually move it into 1st and then this is only good until 35mph. So trying to accelerate say at 33mph is a real ***** unless you manually downshift it but even then you lose the time of waiting for the car to downshift before you can hammer it. Search the previous posts on transmission shift points that were programed by Infiniti to help with fuel economy and also prolong transmission life as the OEM transmission is only rated for something like 330 ft/lbs so Infiniti did not want the engine hitting close to the max capacity of the transmission.

[rover3l]

I had it in Drive and yes it feels like a dead spot, sort of holding back to a certain point and then she flies. Problem was the distance to the next junction was insufficient to make up the lost ground

[elwesso]

The 90-93 really makes that dead spot better, due to the higher gears. 4.08 helps EVEN more!

[dareo]

OEM redline is 6,900 rpm.I can assure you 7300 rpm is quite safe [assuming you don't hold it there] considering the Q short stroke [3.256"] if oil was changed since new at the correct 90 day intervals.I am celebrating my 10th running year with a 7,300 rpm redline and high shift trimode TCU to match........[over 220,000 miles of use] since 1994 on the 268,000 mile 90Q.

Extra 400 rpm is 400/74.0= 5.4 mph in 2nd gear on 90-93Q differnce between 93 mph and 97 mph in quarter mile.......[not wasting 0.8 seconds shifting when you can still be accelerating].

Bear with me here, i'm still new to my Q. I've got a 1993 and i can take 2nd to 97-98mph at just under 7000 with stock tire size. Does this mean i've got a non-stock trans or gears

[rsiwicki]

if you get the jwt ecu/tcu you will run the car till 97mph before it shifts into 3rd. Without it (OEM) you will run till 93mph and therefore require you to shift before you complete the 1/4 mile.

As per Q45tech and all of our experiences a stock 90-93 Q all within specs except for JWT ECU/TCU will only need to shift 1 time to complete the 1/4 mile therefore producing some very good times. Without the JWT ECU/TCU you will need to shift 2 times and the extra shift slows down the rate of acceleration therefore decreasing you 1/4 times. You need the JWT ECU/TCU with the new 7,300 redline to get only 1 shift in the 1/4 for a 90-93 Q. The 94-96 Q's have slower gearing so they should already be able to complete the 1/4 with only 1 shift without using the JWT ECU/TCU