There is a significant difference. Gearing in the 5AT is weak and needs at least 3.7 FD's to compare with the 6MT.

I'm not saying there's a huge difference, but it's significant if the 6MT driver can drive.

(The 7AT is a whole different ball game though).

 

what are you doing over here? Are there any drags happening this week in your area depending on the weather?

I'm here in N.J working and drove my car up. I'm one spot ahead of you on my350z (denchan350gt).

Sorry for going OT. OP you need practice like the others have said and learn or know your car's sweet spot.

 

Acutally no....the auto tranny has different gearing vs stick....A 3.5FD = a 6MT w/3.7FD.

I'll have to dig up the ratio time/for each car. I remember reading about this when I had the 3.5FD vlsd diff a couple months ago.

For the O.P, the first mod anyone should do is the driver mod. Keep practicing on how to launch the car better.

Try to aim for better trap times. Also, look into getting a tune (Osiris if you're staying NA) and swap the diff to one with VLSD(preferably a 3.5 or 3.7FD).

You'll be scooting around here quickly in no time

 

I'm not sure what you're trying to contradict.

Here is the gearing of the 5AT [left] compared to the 6MT [right]:

 

wrong ratios not sure where you got those from

Skaterbasist is correct with the ratios MT 3.5 AT 3.3 you would benfit from a 3.5 you can usually get them cheap or trade with a 6mt TT guy we like the 3.3 better but in your case 3.5 or an after market 3.7/3.9 would help you get out of the hole.

 

You don't have a sedan. Get a sedan and you'll break into the 13s

 

I disagree. Only until you start talking about 6MTs on sticky rubber is there a signficant advantage. Also, you're failing to remember that the autos have a torque converter which assists in multiplying torque. Comparing ratios between the auto and 6MT are pretty much meaningless. Essentially, autos can get away with using a little less gear.

 

All those parts and you haven't even bothered buying a piggyback so you can tune it. Who know were your air to fuel mixture is at. I'm sure that might solve the problem.

 

When I was stock, I had raced a good amount of stock 5AT's during my past drag events. I can say that without a doubt, there is a significant difference (both in E.T and trap speed). Again, im not stating it's a huge difference, but it's significant enough during a race.

As in many cases, experience > theory. (Though they are both important in understand how and why it works).

EDIT: I'm not exactly sure how much of a difference it really makes, but I have a revup. They usually tend to have less of a power drop-off after peak power, meaning it should have a slightly better average power throughout the gears. That's also aside from the difference in drivetrain efficiency.

 

I don't know, man. I look at the 1/4 mile database on here and my350z.com the ET/MPHs were pretty much the same between NA 5AT and 6MT G/Zs. The 6MTs tend to see about 1mph faster traps, but that's about it.

 

The reason you might be bogging quite a bit is because you've got rather significant exhaust modifications with probably too much air flow which kills sub 4000rpm performance. You're probably crawls from idle to 2500rpms, does okay from 2500-4500rpms, and then it's like a turbo. It's the downside to adding all the exhaust work. You've basically killed exhaust velocity below 4000rpms.

 

It was usually a 1.0-1.5 MPH trap speed difference in my experience.

I wouldn't use those databases for comparison just for the simple fact that it's not correct to compare completely different runs with varying DA's and conditions (though im sure you know this).

I wish we had another G/Z track day around here... it's always great running against other G's/Z's for comparison reasons. Too bad drag racing is almost extinct here :-/

 

In my experience racing autos the pulling away starts in the beggning of 3rd gear and on. There was a particular drag day that i remember almost 4 years ago when my car was new. There were about 7 G35s total. 3 of them were 6MTs including mine and that day there was a very consistent difference between all the 6MTs and AUTOs. 0.3 second difference in ET with 60fts being very similar to 6MTs and about 2mph difference in the trap speed. I remember that day because that was the time that i broke the 15 second berrier in palmdale (LACR).

Before putting my cats and the tune. I had Kinetix plenum, z-tube, exhaust, which gave me 7 peak hp and not much difference in the power curve. I raced OCG35 with everything that i had + tune and HFC. He was the first auto ever to give me a good run from start to finish eventhough i trapped 0.5 mph higher. When he changed his FD, his car was much faster than mine and i had to go with tune and then it again become a good race.

All this that im saying happened in one day, races right next to each other and comparing the timeslips over and over.

 

I have VLSD and I always race with VDC OFF. I dont think it has much to do with experience because its an automatic. I do race it in manual mode as well. When I launch the car I hold the brake and rev it to about 2700 rpm. I have a feeling it has to do with my launch. the car bogs up until around 3500 rpm. I think if the stall was higher and I launched at a higher rpm it would get the job done.

I'm still really confused why I can't hit 13's.

 

Also forgot to mention that my engine bay has alot of heat soak but I heard thats pretty common with VQ's.