I have been wanting to do gears to my car but there are other options. I track my car (1/4) but mostly enjoy it being quicker on a roll. I have heard people say that gears are better for the streets. I have also heard that in cars with eaqual ETs, that the one with the highest trap will be faster on the street. I dont know If there is relevance there because its hard to tell from the fast list if the geared cars trap higher.

My question is.. If I put gears on my car will it make it faster on the street?? I have heard people say that the track says not much but that its real good for the street.(3.42s on a A6)

I might not be ready for the ups and down of a cam but maybe.

Thanks!
Rod

 

You could actually go with a 3.15 gear set and get comparable results to the 3.42 with that tranny. The subfloor has had both sets in his car and didnt have a noticeable difference between the two on his A6. Your car with feel torqier (if thats a word) and the car will get into the power band quicker. You may lose a few mph on your trap but I highly doubt it. You will probably get quicker off the line which will bring your et's down. There is defenitely a benefit to be had from gears if there wasnt race cars wouldnt have them. Its just a matter of getting the right ones for your set up.

 

Thanks Batman,

So it will make it faster on the take off but slower on the roll? That's what a lower trap means right? Some people pushing gears say that it will make the car accelerate faster from any speed?


What I thought in my mind was that it accelerated harder in gear making it faster but required more shifts evening it back up.. But harder acceleration in gear.

I'm trying to wrap my head around this as 2k is a considerable amount that can be put towards a down for a Z in the future.

 

With no other changes, going from stock gears to either 3.15 or 3.42's will feel like you've got an extra 100 HP.

They do help at the track but not by as much as you would expect because of the A6 drive ratios. After blowing my 3.42's last year and briefly going back to a stock 2.56 setup I ended up seeing a little over a tenth of a second with the 3.42s.

 

You will accelarate harder in every gear. The only reason you would experience a lower trap speed would be if you tranny had to make an additional shift before you trapped addint time in for the shift. Say you normally trap in 3rd if you go to high with the gears it could make you finish in 4th creating an extra shift. You should be fine with a 3.15 or 3.42 though. You will need a tune with gears also to plot the new shift points etc. so take that into consideration as well.

 

Thanks for coming in Subfloor! I was going to pm you. I saw that TonyB4 once said that gears were good for a tenth based on a comparo between you and him. Giving the credit to the gears.

100hp sounds like a blast! How does it feel that way yet only shave a tenth? Is it faster on a roll?

 

It’s funny you ask about how it feels from a roll as I can’t really comment on that (or how my car downshifts) because when I punch it, doing either one will usually put my car sideways. If however I’m very careful not to get on it too much it will throw you back in the seat noticeably harder.

I don’t know how to properly explain the physics behind it only picking up a tenth while feeling totally different, but I was pretty surprised as I too thought it’d be worth more at the track.

 

The other thing that might contribute to the gears not helping as much as expected is because I’m already running a high stall converter.

Since the purpose of the gears is to get you into the powerband quicker, the converter is already doing that and I’m guessing it probably negates some of the benefits that you’d probably get with just gears alone.

 

Thanks man. I know you've done all kinds of things to your car including the LS7 swap. So it would be hard for you to single that mod out. Good point to mention that the tenth shaved off is what it bettered a car with a stall. The faster you are the harder it is to go faster right?



Thanks

 

Welcome.

It’s been said quite frequently before but it really is true – if you’re looking for a noticeable improvement at the track then go with a high stall converter as I picked up almost 4 tenths with my Yank. If however you’re just looking for a pure SOTP improvement then go with gears.

Yeah, pretty much.

 

I know that your set up of gears went well with your stall after tuning but Im only ready to do one. I've heard drivability suffers with converters light to light. Does the converter help from a roll? If not I think I have my answer. One more thing.. 3.42 or 3.15?

 

A converter does help from a roll but probably too much as it’s one of the reasons I can’t floor the car anymore - I used to have the Traction Control kick in at 70MPH (while I still had the LS2 in the car) if I stomped on it.

I didn’t notice any difference between the 3.15’s and 3.42’s around town but there was a noticeable difference on the freeway. With the 3.42’s the car revved noticeably higher but the upside is that I can pass people in 6th gear without having to downshift.

If you do a search on my name I started a thread quite a while ago where I posted the freeway RPMs that I was seeing with the 3.42’s.

 

Ahh then it sounds like 3.15s would be better if there is no noticable difference on the street. Noticeably higher rpms on the hwy with no gain on the block settles that for me but you got the 3.42s probably cuz the stall?

You mean that the stall helps so much that you break traction on a 70 punch? Is that with the paddles in gear or after the skitzophrenic downshift on S or D? I never do that as it feels like an explosion with bullets and LTs. maybe it's my tune? Nah, it's an explosion!

I have to join a local club so that I can see. This all comes from missing my mn6. It was fast on the roll punch. I prefer in gear pull

 

To be honest I originally got the 3.42’s because I had just blown my 3.15’s at the track and thought they would noticeably help improve my ETs.

Yes, with the higher stall as soon as you floor it the engine RPM jumps up really quickly and the increase in torque multiplication (which is one of the other benefits of a higher stall converter) causes the tires to hit the ground much harder.

The traction control would kick in after the downshift because of the converter, but even if I was in paddle mode I could still break them free (depending on fast I happened to be going) because of the gears.

 

So to sum it up.. you recomend 3.15s over 3.42s? Also that the converter is better for the track but gears make you faster on the street roll off. Is this accurate? How was your cam?do you recomend camming? This is my DD.

I really apreceate you taking the time to school me. I was surprised to see that you were faster at the track with the 17s. congratulations on the 10s. Spin recomends the widened 18s as Im sure you've seen.The stock look is clean and clever.

I'm at 12.15 in the 1/4 which means that Im a slow as bitch next to you. What rpm did you launch with the 2.56s? Would DR let me launch at a higher rpm?.. Nitrous??

 

Yes, that is correct.

For what you're looking to do I think that 3.15's would be your best bet overall.

It's difficult to suggest whether a cam would be a good choice because it can really change the overall driveability of the car. I currently have a huge cam in my car right now and wouldn't think about ever going back to a smaller one, yet most people would probably think I was nuts for going with something that big. For you I'd recommend going with the gears first and then if that's still not enough consider a cam later.

At the risk of getting into a "which drag radial setup is better" I disagree with Spin as I've run a smaller 275/40/17 at the same track on the same day as two different sizes and brands of 18" tires (295/35/18 BFG's and 305/30/18 MT's) and found that the 17's gave me much better 60ft times and ETs.

I used to swear by the MT 275/40/17 drag radials for the longest time but have since converted to the same size Hoosier after I started cutting consistent mid 1.4x 60ft times.

I only ever ran my car at the track with 2.56's the one time, but have driven a few of my friend's cars and found that launching just slightly above idle gave me my best times.

Yes, drag radials would let you launch at a higher RPM but without a different stall and the tuning changes to accompany it there's gonna be a limit beyond which TM will start to kick in and actually make you leave slower. Surprisingly enough you don't really have to leave hard with gears and a converter as the 1.4x 60ft times have all come with me leaving at around 1300 RPM.

Nitrous? Naahh, stay normally aspirated as it tends to impress people more!

 

I think my TM was tunned down. 1300 rpms with the gears is like launching at a higher rpm with the 2.56s though but even more changes with the stall I bet. I got 12.1 with a 1.9 60' leaving at about 1200rpm. non DR.

On the fast list I saw a guy with a .3 faster 8th then 1/4 than me. All he had that I didnt were the DR and the improvement was in the 8th wich includes the slipery 1st to 2nd shift.

There is a local guy selling a repro " almost" stock looking set up. 17X9.5 in front and 18x10.5 in the rear. That seems like the same size 17 you were running, no? Plus a set of 18s! It seems like two usable sets of rear drag wheels and tires.

 

Don't forget the effect of tire diameter on final gearing.

275/40/17 dia is 25.66"
295/35/18 dia is 26.12
285/35/19 dia is 26.85 "stock".

The 17" tire with 3.15 is nearly equal to the 18" tire with 3.42.

 

Goog info! You know, I thought of that. I even wondered if I could put a set of fronts on the rear and get a sample of a different gear ratio but the fronts are just about the same diameter as the rears, no? Or would this make sense at all?

If I do gears I will likely go to an 18 wheel to have DR on the daily affecting the overal drive ratio. So then 315 will be like 342s??

Ok so Sub was using the 17s at the track not for the street comparo. He had 3.42s on with the 17s making that like having what? 3.73s on the a6 Sub ? Or did I miss something?

 

SgtRod; A good tire dia. calculator is:
http://www.rx7.org/Robinette/tire_diameter.htm

My ball point calculator isn't working to well this AM but it looks like about a 5% diff from the 17" to stock.

You are giving up a little traction though, the 17" is shorter and narrower (smaller footprint) than the 18".

Too bad there isn't one tire size that would work best for all track conditions.