Everyone says that when you start modding, you have to specify a goal, then form a plan to achieve that goal. Here's my goal:

I want to trap 107mph, on street tires, without a gear swap. Right now, in extremely good conditions(the conditions being discussed elsewhere), I trap at 102, with a 103 on a spinning launch thrown in. So, I have to trap another 4.5+mph to achieve a 107.

Right now I've got a ztube, k&n, 350z midpipe, and crawford cats. I will be getting the MREV for Christmas. After that, I plan on putting on a stillen airbox, then a stillen catback. Next I would like to put on some strup headers. And to pull it all together, I plan on getting some sort of ecu; at this point I really like the UTEC. But I do *not* plan on pullies, heads, or cams.

The last time I dyno'd(with the kinetix cats instead of the crawfords), I put down 248/233. Actually, I put down 249/238, but there was an anomolous reading at the end of that run. Anyway, with the planned mods, I hope to put down 270hp at the least, and hopefully in the neighborhood of 280hp at the most. So, without discussing the actual curve, will 20hp get me another 5mph in the trap? No way.

A month or so ago I went to the track and established a new personal best of 14.16@100. After that, I figured with a little prep and better driving, I could hit a 13.8@102. That was my goal. The next trip, I didn't get there. In fact I only improved on my previous best by something like 7 hundreths of a second, and 1mph. However, on the trip *after that*, I did in fact nail my admittedly aggressive goal.

With that in mind, I think I can still improve on my current personal best in my current trim(without the soon-to-be-installed MREV). I believe I can hit a 13.6@103, or maybe even a high 13.5@103. I think this because after going back and watching some film of my shifting, I am taking WAY TOO long. I figure I can take off a tenth, at the minimum, with better shifting. The problem is that I'll never know if I'm right or not. The track is now closed at night, so I can't run in the same conditions. Also, I won't be able to hit the track again before installing the MREV. Therefore, any improvements that I make(if any) might be attributable to the MREV, and not necessarily better launching/driving.

So, if I have another 20hp(after all the planned mods) across the entire power band, in all gears, I figure that's good for 2.5mph(roughly). Add another 1mph with better driving/shifting, and I should be trapping at 105.5ish. So I gotta figure out how to eek out that last 1.5mph.

These are extremely lofty goals. I might not be able to hit them. I've got to reach a ceiling at some point. But in the past, I've posted quite aggressive goals, and despite the disbelief of some, I've always reached them.

This process will be long, and expensive. I might never spend all the money required to purchase/install all of these mods. One might point out that for the money, I could go FI. But if I can actually reach these goals, I'd be pretty damned proud of a g35 sedan that can trap 107, all motor, without nitrous. Plus I'd still have the factory warranty and reliability of the near-stock setup.

So, please offer your thoughts/opinions. If you think I'm crazy, and there's no way I'll ever trap 107, then that's cool; post that as well.

 

Are you wanting to keep the stock wheels or are some lightweight ones an option? Other than that I can't think of much to do besides engine work such as boring it, port polish, or cams. You could try eliminating he cats altogether too I suppose. Good luck on your goal, it'd be nice to see you hit it.

 

Ok, what is the definition of "Street Tires" You could get drag radials that would help alot. But if you are trying to stay with stock tires then a lighter flywheel and clutch wouldn't hurt.

 

I plan on retaining my current wheels. They're not stock, but with tires almost exact same weight as stock. And I also plan on keeping my current all-season tires.

 

Then it looks like you should go that route. Pricey, but it will help pick up some time due to the faster reving of the engine.

 

IMO, I think 107mph traps will be pretty hard to come by in NA form. I know a handful of 350Zs have exceeded 106mph traps, but they are pretty rare and typically run on some of the best tracks in the nation. Seeing that the G has about a 200-250lb weight penality, it only make things harder. An LS1 Z28 6MT weighs about 3,300lbs typically makes about 300whp/310wtq. Those cars typically see 105-108mph traps. I think that should give you an idea of the power to weight ratio to need to achieve.

I know that with my 205whp/195wtq VQ30 Maxima (weight 2920lbs- no driver), it took an average of 25whp to go from solid 96mph traps to solid 99mph traps. With a different intake manifold, I increased the power from 4800-7000rpms by about 10 to 55whp depending on rpm. Above 6000rpms, I was making an additional 35-55whp/wtq over the stock intake manifold.

There is a guy on Maxima.org with an 02 Maxima 6MT. He has achieved 12.8s@107mph with a 1.9 60'. He also races at Rockingham which is a damn quick track. His VQ35 makes 270whp/265wtq. This is what it took for him to achieve 107mph traps:

1) removed seats, bumper supports, no spare/jack, no PS or AC (3050lb curb weight)
2) 32lb 23" slicks combo on ultralight 15" rims (45lbs less rotational inertia)
3) Completely revised intake manifold that dramatically increase power above 4500rpms
4) ECU, headers, SAFC, intake, catback
5) a deeper 2nd generation Altima ring and pinion gears
6) 15lb battery

His Maxima basically has the same power to weight ratios as a stock LS1 Z28 6MT which is 11.3:1 vs 11:1. If your G (3,450lbs) made 270whp, it would have a power to weight of around 12.8:1.

I think 104-105mph traps are with all the mods you listed, but trying to gain an additional 4.5mph in trap is quite an undertaking. I'd say it would take an average of about 40-50whp to achieve another 4.5mph in trap. Consider the fact that an 80 shot of nitrous typically gains a G35 about 6 to 7mph in trapspeed. A 100hp shot is good for an honest 90-100whp and about 130wtq. More importantly, the nitrous completely elevates the entire powerband by 100whp/130wtq nearly the second it hits. That's why it's so effective. if it takes that much power to increase trap speed by 6 to 7 mph, you can see why it would be so hard to gain 4.5mph NA when the power gains are more linear and don't elevate the power under the curve near as strongly.

I'm not saying it's impossible, but I think 104-105mph is more realistic. Hell, that's damn near what a 333hp E46 M3 traps at.

I know that you're thinking you could improve your traps by simply driving better, but trap speed is really a hard thing to mess up unless you're misshifting, letting off before the finish, hitting the brakes, or spinning REALLY badly into 2nd or 3rd. I'm not talking about prolonged chirps. I'm talking about spin where the back end gets loose and the rpms shoot up like you're in neutral. Regardless if you shift really hard or decently hard, your trap isn't going to improve unless you're totally granny shifting which I have a hard time believing seeing that you've ran over 100 times this year. Shifting and launching effects ET. An messing up MPH is really hard to screw up. In all my cars, bad 60 foots were met with bad ETs, but MPH hardly ever changes by more than maybe .5mph. Now if I misshifted or spun wildly into 2nd, then yes, my trap would be effected by 1+mph.

I gotta ask, why the Stillen Airbox? The 350Z guys all agree is simply a noise maker and the dynos show neglible gains. Why waste the money? Why not spend the $350 on 18" DRs? If you want more noise, just yank the Power Duct cover off.

 

Maxima : Z28 LS1 (or G35 whichever you want to pick)
FWD : RWD
Can't really compare the two because RWD cars has a much greater drivetrain loss and vehicle dynamics in weight shifting are different.

 

Sure you can It doesn't matter about the drivetrain loss, it's the power at the wheels, shape of power curves, the weight of the car, traction, and gearing that dictate how fast/slow a car will be. A 1.9 60' in a FWD car is the same as a 1.9 60' in a RWD car.

 

so what you're saying if the a fwd with 300whp/300ftlb-tq with same gear ratios, and curb weight and some other things, will have the same time as a 300whp/300ftlb-tq rwd car of the same physical characteristics?

 

Sure assuming the 60 foots are similiar. Do you think the acceleration forces are different or something?

Look at a comparison of my 96 Maxima (14.5:1 power to weight) vs my G35 (~15:1 using the average dyno numbers for a basically stock 5AT sedan):


Maxima
60' 2.182
330' 6.053
1/8 ET/MPH 9.268@78.19mph
1000' 12.040
1/4 ET/MPH 14.370@99.34


G35
60' 2.190
330' 6.133
1/8 ET/MPH 9.334@76.92mph
1000' 12.079
1/4 ET/MPH 14.383@97.78


The Maxima had slightly better gearing and a slighly better power to weight therefore the high MPHs, but as you can see, both cars are very close (within 0.06 to 0.08 seconds).

 

sorta, it's the way the forces are applied and what other elements are resulting from acceleratoin. whereas on an FWD, traction is reduced from the front end upon starting...you know, like those crazy fwd drag cars that spin the crap out of the tires from the start. and with rwd, additional force is being applied to the rear. even if the suspension is setup it it's prime, there's no denying those forces...a good setup buffers those forces.