Stopsign32v

iTrader: (1)

I just ask this because I've notice that my 1-2 gear is fine but once I shift to 3rd it seems the RPMs fall off the side of the world. Is it even possible to put in a 3rd gear from a GSR only?

Who all is running a stock LS trans and is being successful IYO? I also kinda thought about changing the final drive only but not sure that would do anything good and might make things worse. I dunno, just figured I would ask and get opinions.

TheShodan

iTrader: (14)

Yes. Changing the final drive alone turns the LS transmission around quite well. People do create hybrid transmissions (I know I have) out of the LS trans all the time.

The way that it sits, unless you're using an LS engine, is...horrible idea. But it also depends upon the turbocharger that you're using.

I'd never use a stock LS transmission. I'd use one, yes, but I'd have to change a few things.

Stopsign32v

iTrader: (1)

I'm all ears. I'd love to use my transmission if I can. Its in great shape. In for more info for now. Still buttoning down my motor ideas for the future. I just want to find out if there is hope or not for my trans or if I should jump to a GSR.

Turbo wise right now I'm really leaning towards the GT2871r

Stopsign32v

iTrader: (1)

This link shows all the trans ratios Specnically Speaking: B-series Gear Ratio Guide + More!

So in final drives it seems you can go from a 4.2 to a 4.4 (GSR) or a 4.7 (ITR). My math really sucks but in 5th gear going to a 4.7 you could expect around a 500rpms increase around 70mph cruising?

As far as performance I would expect the 4.7 final drive to make a substantial improvement over stock.

Here is a nice video of 4.7 final with a good turbo

TheShodan

iTrader: (14)

Yes. Much more elaborately stated, but yes. I guess me not having a video made my testimonial rather worthless

NotARaCist

iTrader: (1)

Don't forget Shodan, #NoBuildThread.

The LS transmission is worthless from a performance standpoint. You can use the Zeal Transmission Calculator if you want to be really picky about what gear goes where, you could just get a GSR transmission, which will outshine the LS in basically every metric that matters. Or, if you're feeling particularly ballsy, you could step up to a CTR/ITR transmission, enjoy your newfound LSD, and have gearing tighter than your first high school girlfriend's *******.

TheShodan

iTrader: (14)

Ah yes.. #NoBuildThread, so what the hell do I know. I think that when people have the option to not get an LS transmission, it should be exercised. But, in the event that this is all one has, there are ways to make the transmission at least livable to a point where it can keep its performance advantage. The MFactory transmision scale does a much better job at being able to help one utilize a particular final drive as a great torque multiplier.

MFactory® Competition Products - Gear Ratio Calculator

From one who's had a few transmissions, I can honestly say that as much as I don't like the LS transmission in its stock form, when combined with a 4.785 final drive (my buddy and I were able to work an OEM Type R one into the transmission at a time when MFactory weren't around to make specific Type R final drives to fit the LS/B16 family, from the GSR/ITR family, which normally don't cross-fit with one another) can work wonders. Even if changing several individual gears out, it's not the worst thing in the world to deal with.

I guess I don't worry about what rpm I'm really at w/ 70mph. I'm usually not in enough engine load to worry about it. What I DO get concerned with is when I'm tapping the accelerator at speed, I need boost recovery to come in without having to down shift 2 gears just to get the car to move: This is when I know I've gotten the right FD and gearing..

Here's the comparison chart


In the end, I mean to say that with these B-series transmissions getting more and more rare (you may not think it is now, give it a couple more years, you'll see), you need to know that you can MAKE a great transmission out of something that isn't that great to start off with.

Geis

You do realize cars like the the new corvette have such longer gears because with extremely short gearing and the amount of torque it has = wheelspincity
That's why not many people run b16/itr trannys for boosted builds, especially with fwd and no weight. You are just getting rid of any chance of hooking in second, and furthering endangering 3rd as you up the power.

Tighter than my highschool gf's ******* is but the LSD is sorta worthless as you increase power. IIRC the OEM LSDs don't hold very much power.




@Theshodan The only thing that's not the greatest about the LS no matter what FD you run, is the gear spacing isn't optimal for staying in certain power bands at certain speeds. This is why I've heard everyone loves the GSR tranny so much, semi short gearing and FD with good gear spacing.

NotARaCist

iTrader: (1)

Are you...actually comparing an older 4 cylinder Honda to a new Corvette?

Geis

Oh wake the f*ck up man, you don't go for even shorter gears on a boosted build when traction is already going to be a problem for 2 of your gears. Sure, maybe 3rd and 4th will be even quicker for pulls at speed, but overall the GSR is a much greater compromise. The comparison has nothing to do with age, want me to get you the gear ratios for an 80s corvette? Sure, may have a completely different torque curve but the reasons for their longer gears are just as valid.

2kdrift

lots of ways to improve traction, shorter gears are always better as long as you can put the power to the ground

Geis

did you purposely ignore everything I typed or what? You're not going to get any traction in 2nd gear rather quickly as you add power, and 3rd may become an issue too depending on your torque curve. No tires, traction bars, motor mounts, coilovers etc. are going to fix that. It's a fwd car ffs, they're not made for this much power whatsoever.

It also depends on how you would like to drive the car. If you never wanna go flat out in the lower gears and don't have a problem with shifting through gears more frequently and revving higher/driving slower on the freeway then yes b16/itr route all day. For anyone who doesn't meet these criteria, you may want to look at longer gearing that's more reasonable for streetable/launches/etc.

2kdrift

that really depends on your setup I have had 2 turbo hondas that had no problem in 2nd gear first wasnt bad either...that was on low boost

ever hear of something called boost by gear, or maybe traction control?? hmm I wonder what that stuff is for

hw612

...so like a b16 final drive in an ls trans would be decent?

m4xwellmurd3r

To improve traction on a car with lots of torque, you can use longer gears to reduce the torque multiplication of the transmission. Shorter gears are great for low output engines because it multiplies the torque many times. It has the cons of lower top speed, and more frequent shifts, but with the pro of being quicker acceleration.

a turbo car with tons of torque could be helped by having a longer geared transmission if the torque output is causing horrid traction issues in the lower gears due to the torque multiplication of short gears.

it's pretty basic ****. i don't understand why you think shorter gears=better traction.

2kdrift

never said that shorter gears=better traction.........show me where i did please.

I simply stated as long as you put the power to the ground (i.e. no traction problems) then shorter gears are better. Believe me I understand completely how longer gear transmissions work, and the benefit they will have when it comes to traction in lower gears.

Its not always so cut and dry with options such as BBG ect
lots of ways to avoid "horrid traction issues". Good suspension setup, tires + BBG

2kdrift

I would say yes...with that final drive It would be the same gearing as a GSR trans for first and second gear, 3rd fourth and fifth would be slightly longer.

best bet is to check out the chart shodan posted. Lots of opinions here pretty much nobody is going to have the same build, purpose, and desires so its kinda like up to you. check out the zeals transmission calc also.

between the two you should be able to figure it out.

hw612

i have a buddy that has gsr 1-4 gearsets in his ls case with ls final drive and 5th. pretty awesome combo for roll racing and street ability. probably the route ill be going.

blackeg

that's the combo I have in my turbo car but with a 4.4 fd. ita great since the car makes enough power to get theough the gears in short order plus with the 24.5" tires it puts me thru the traps a few hundred rpm shy of the limiter in 4th gear

Stopsign32v

iTrader: (1)

Is it possible to put a 3rd gear from a GSR in a LS trans to get rid of that big dip in RPMs?

LD9Stunner

I'm rocking an ls trans with an mfactory lsd on my turbo gsr and have no complaints. It's ideal for a daily driver which is what the car is primarily used for. Could it be .2 faster with a gsr or hybrid setup? Definitely. But I enjoy the 5th gear rpms and the trans was in tip top shape when opened up so decided not to mess with it.

ls-t eg

3-4 goes together. If you switch 3rd gotta switch 4th. I'm doing that now, ls 1-2 an 5th gsr 3-4 an 4.4 final. Pretty much gsr trans with ls 5th but I started with ls trans an don't end up with dual cone syncro. I'm pretty sure 1-2 is almost the same between the two don't quote me on that though.

TheShodan

iTrader: (14)

Duly noted. I'll leave it to you then.. Not to sound snippy, but when you have an LS transmission, and start manipulating it like I have, come back to me with better feedback than that.. Otherwise, you're just giving me theory with no application based upon popularity polls on the forum.

And Yes, shorter gearing on boosted applications puts torque lower in the powerband, and, as long as it's not too short, has very good benefits. Not everyone is trying to drag race by stomping on the damn accelerator. Other racing types even on the street exist, but it also depends upon the general size of the turbocharger used. Even newer 6MT have shorter FDs and gearing on smaller displacement turbocharged applications (2.0-2.4 litres) to get torque to maximize at lower rpm levels. This is becoming more and more common.

Look at what I wrote. re-read. I'm not going into redundancy, it wastes time. I specifically pointed out about the LS transmission as not being OPTIMAL as it sits. However, I SPECIFICALLY stated that there are ways to manipulate the transmission to work well, if there is no other alternative, or if you have specific needs for a turbocharger that it's based upon. Then I added additional calculators regarding FD and other torque multipliers..

Not everything is TL;DR.
Perhaps I was better off remaining silent...

TheShodan

iTrader: (14)

SEE CHART ABOVE.. Apply it to the calculator ABOVE. Use your noodle, here, my friends. "Decent" is a subjective term. That's for you to decide, and eventually try out.

TheShodan

iTrader: (14)

SEE CHART ABOVE. THAT ANSWERS THAT QUESTION FOR YOU.

Does no one read?