Arrvaxx's quest for the 10s.

Arrvaxx

The insane power that my Fast Intentions turbos provide and the lack of boosted 'representation' on the 1/4 mile thread has inspired me to taking on a quest: 1/4 pass in the 10s.

There are some rules. This is not about a drag build. My 40th Anniversary is a daily driver, a track car, a show car, and now a drag strip car and I will not ruin one aspect to maximize another. Versatility is one of the things that I love about the Z cars.

Rule #1: No permanent mod may significantly impair the car's ability to perform in any other category.

Rule #2: A permanent mod is one that cannot be used when driving the car to an event, cannot be changed or modified in 60 minutes only hand tools and a floor jack, or cannot be carried in the car to an event where it is installed. This time is cumulative both at home and at the event. A mod is considered permanent also if it requires changing fluids.

Rule #3: Driving characteristics can be changed as long as I can change them back to 'normal' and still conform to other rules.

These rules mean:

- I cannot use slicks because slicks cannot be driven on the street and I cannot use a trailer to transport them with me.
- I can swap coilovers with different spring rates either at home or at the event.
- I can change brake pads but not brakes.
- I can do a bit of weight reduction. Not sure I could swap seats and make other changes in the 60 minute limit but it would be legal.
- I can adjust camber -if- I can prove to myself that I can get it back to 'normal' consistently. If I can't and changing it requires an alignment then I will have to deal with the camber I have since some camber is required for the track and show.

This thread is about my quest, my journey from strip virgin to seeing 10s on slips. I'll post setups, pics, vids, slips, and impressions after each event.

This thread is -not- a drag racing tech thread. That thread, as it relates to me, is HERE. There we can discuss and debate everything. Please leave this thread to laughing at my noob shifting technique (but offer advice on the -other- thread) and other general nonsense.

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Arrvaxx

First drag event ever is next Wednesday, August 27th at Brainerd International Raceway.

Since it is my first time *blushes* I am leaving everything the way it is except camber. I would like to see if I can get it closer to 0 and back without much fuss. We'll see.

My OEM tires are shot so I ordered new ones all around, Hankook R-S2s. 275/35s front and 305/30s rear. I'm going to leave the OEM fronts on but mount the 305s to the rear. After the event I'll change to the 275s in front. Technically this isn't against my rules since I am not mounting tires just for the event. I am moving to 305s for every day use anyway and just not mounting the 275s (stocks are 245s) until afterwards. Not that it will matter if I have 245s or 275s on the front when I am likely to miss three gears during the run.

Unless my first run is magic I am going to stick with 93 octane on my 91 octane tune. It is hard enough to keep the tires from letting go even in third. I need to get a few dozen runs under my belt before unleash 604hp!

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phunk

Youre about to find out precisely how crappy the 370z is as a drag racing platform in its natural state!!!

I think with a lot of work, practice, and thinking you should be able to get an occasional 10 second pass following your guidelines (which pretty much limit you in every way except for running a big 18 or 19" tire)

Adjusting the alignment yourself for the camber can be done, but its not as simple as just adjusting the camber. When you move the camber, the toe changes a ton. I would recommend putting the car on an alignment rack and setting the alignment both ways using only the eccentric bolts to make the settings, and scribe the 2 positions for each adjuster on the crossmember so you can go back and forth as you wish. You will probably find that with 0 camber you dont notice any negative effects in handling on the street, and just leave it that way. The only negative I have found of running at almost 0 camber is that it looks stupid on this car... due to the body shape it actually looks like positive camber. But even on the street, you will want all the traction you can get, and I dont imagine you dialing the alignment back in to the slip-and-slide position after you see what a little more grip feels like.

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Arrvaxx

Good advice. We are lucky and have a hardcore alignment guy in the cities. He does a lot of the race car setups. I'm sure he would be willing to let me move and mark. If that worked I'd be pretty pleased. Can't have 0 camber in a show!

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Arrvaxx

Went to Brainerd International Raceway's Wednesday Night Drag Races last night. Results were mixed but overall for being my first time I am pretty please...and had a hell of a time anyway.

For you guys that just can't wait:

Tires: 305/30r19 R-S3s rear inflated to 25psi cold/30psi hot. 245/40r19s Protenza inflated to 38psi cold and hot.
Suspension: Swift lowering springs, Whiteline rear diff bushings.
Gas: 93 octane on 91 tune, half tank.
Weather: 75 degrees and overcast.
Other: Zip. I didn't take anything including the spare out.

Best run: 13.21 @ 115.92mph.

Ok, now the more interesting stuff...this is a journey thread anyway.

The car is 100% responsible for not making the driver look like a fool. No, not kidding. I have a long way to go when it comes to launch. I had a really hard time holding a consistent RPM below 3500 or so. I gave up and tried launching at 3500 but would either get wicked spin or red light trying to ease the clutch out to avoid that spin. Annoying but hey, virgin over here so whateva'.

Out of 10 runs I only blew three shifts which made me happy since the week before at an autocross that included a runway run I was missing them all day. I really saw the benefits of a short shifter. Put that on the list.

The car is a monster. We don't have a lot of 370Zs up here in Minnesota, fewer that are boosted (most are supercharged), and even fewer are raced on the 1/4 or track. So when I would screw up a launch and still run down a Mustang XYZ I got some looks. Even the announcer made a comment about what was hiding under my hood. That was fun.

So I have 1.21 seconds to shave before the 11s. I know that 100 octane will get me most of the way there and a proper coilover setup will seal the deal but I want to get in to the 12s without either first. They are so close and getting there will tell me a lot about my launch control improvement. And at this point it is clear that to get in the 10s it will take a combination of 50% launch improvement and 50% improvement in the set up.

Attached Images

2014-08-28 10.08.47.jpg (226.6 KB, 26 views)

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Mitco39

I found with this car you'll need somewhere around a 125 trap to get low enough in the ETs. Like Charles said these are just not drag cars. Hell up here James (Jmac88) is doing everything he can just to get into the 11s at ~120MPH.

Your making a very tall order for yourself, but I look forward to seeing how you go about it.

Goodluck!

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2007 Chevy Duramax - EFILive Tuned By Me
2010 40th W/ Nav - Boosted Performance - UpRev Tuned By Me
The Mrs. Ride -2012 335XI N55 BMW - Cobb Tuned By Me, Built by her
My Build --> http://www.the370z.com/members-370z-...39s-build.html

4TthAnnyZ

IIRC a factory sport touring (with a professional driver) will do a 13.1(ish) in the 1/4. With your power and some practice I don't see why you can't drop that 13.2 way way waaaay down.

phunk

With your current tire setup, I wouldnt even be trying to launch at all! I would roll out and ease in the throttle. Those tires arent gonna hold nuttin!! Ease in that throttle and dont try and pull much harder than stock through first gear, and into second push it a little harder, then by 3rd you should be able to go full throttle if the track is a little sticky.

Your trap speed shows some promise. You will get well into the 12's with your current setup and practice. I think you will need tires and alignment to get middle 11's.

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Arrvaxx

Thanks phunk.

Talk to me about what you consider a roll out. Like aggressive red light launch or not even that?

What about when to shift out of 1st? 6500-7000 comes so freaking fast. Should I shift a lot sooner like at 4500 or 5000? The turbos really come on hard in second but I feel like they aren't helping much, or are hurting even in 1st so I feel like I want to GTFO of 1st quick. But psychologically it is hard which is why I didn't try it last night.

What about RPMs after 2nd? Like I said, things come up so fast and while I think my shifting is crisp I don't have a short shifter. So I was shifting at 7000. This leaves me one tick from redline in 4th crossing the line. I know that I have to be well in to 5th if I go any faster...question is how to get in to at the right time. *Edit: I just watched the videos...I was shifting after 7000 but before readline.

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phunk

Generally, you always shift as late as you can due to torque multiplication. But when you have a scenario where gear A or gear B will BOTH just light up the tires anyway.... well in that case it makes no difference aside from what is easier to drive... and that will be the taller gear. If you still cant go full throttle in second anyway, then I would experiment with early shifting and seeing if you can do it without the car landing too low in the powerband in second. Otherwise, always shift as late as you can.

One thing I have noticed about my car, it doesnt like to shift while the wheels are spinning. I havent really sat down to think about that one... but I have observed that if I am in first gear banging the rev limiter from tire spin, its not going to let me into second (nasty grind) unless I let off for a moment. I assume the tires and drivetrain need to decelerate down for everything to be happy and allow the shift, just havent really thought about it yet.

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GaleForce

I have the same issue. I try to get out of first as fast as I can with reasonable throttle input, then mash *within reason* the right pedal from 2nd, on.

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Mitco39

Never thought of that before but you guys are right. Banging second gear can be difficult, it would be so awesome to have a torque limit per gear so you could contain it down low. Every other gear works flawlessly, I can no lift shift all the way down the track with no issues. Its just that 1-2 which kills the ET.

__________________
2007 Chevy Duramax - EFILive Tuned By Me
2010 40th W/ Nav - Boosted Performance - UpRev Tuned By Me
The Mrs. Ride -2012 335XI N55 BMW - Cobb Tuned By Me, Built by her
My Build --> http://www.the370z.com/members-370z-...39s-build.html

Rid3_FaM0uS

I too recall having that issue several times! id drop the car down into first to do a little pull and shifting at 7500-2nd gear my clutch would just screech instead of changing gears. makes me worry about no lift shift in my racelogic honestly I don't want to be causing inadvertent damage to a trans/clutch/flywheel.

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Always under construction. . .

Japanjay

I will come off spinning while feathering through 1st to 7.7k and bang the **** of second with no problems with the tires spinning.

If you want to hit your goal, you will need to run M/T street Pro's and click off at least a 1.4-5 60'. I like your ambition but you will never hit into the 10's without leaning more towards a real drag set-up. I got a friend that has a 2013 ZR1 with a tick over 1000whp and runs cheater slicks and best yet was a 10.1. He isn't really launching but rolling on the throttle. He can roll on throttle and catch up at the big end with the power, you are going to have to heat the tires up and launch the **** out of it. You don't have the power to pull a 10 down in the big end, you are going to have to make between the 60 and also the big end.

Japanjay

Oh, I am not boosted and was on **** rears when I clicked off a 13.4 @ 103. You have the MPH at the finish, but your first half has massive room for improvement. And 1.9 60' which is still crap.