Hi guys,

I was checking the gear calculator on Mfactory and it seems that the Itr with 4.05 mfactory final drive and the Gsr tranny are mostly the same.

For the strip with a civic that weighs approx 2200 and with 630hp,which tranny do you go please?

I have both trannies sitting in my garage and don't know which one to put on my car.

Some help from you experts would be a great help

Thanks

 

sell the itr for the $$$
go with the gsr

 

Even if the ITR has the 4.05 final drive?

Thanks

 

go with the gsr trans, sell the itr

 

X2

 

GSR is the way to go.

 

i'm sure you guys have your reasons, but, what are they? i was reading this and thinking to myself. if the b16 gears are used with a 4:05 FD you would get a taller first gear than the GSR box has and a tighter 2nd-5th with an overall similar to the GSR as the OP stated. the taller first gear and closer second seem like a benefit to traction and the powerband of the motor since you don't have as large of a 1st-2nd drop as you would with the gsr.

 

Is ethier one LSD?

 

put a taller tire u get taller gear. why waist a itr trans at the track?

 

I have already Mfactory 1st gear in my ITR tranny and also I have another Mfactory 1st gear in my garage so if I decide to go with the GSR , I ll put it in.

Thanks guys for your infos

 

If you already have a MFactory 1st gear that you are willing to put in the GSR trans why not take the Mfactory FD out of the ITR trans (think youd just take the whole diff out since the bolt pattern is different) and then youd have the best combo!

 

So you are saying a Gsr tranny with Mfactory 1st gear and Mfactory 4.05fd?

 

If i had a car that had your power to weight id say the combo would be nice... Since you have all the parts there might as well try it.. I personally do not have any experence with either of the parts (FD or 1st gear) but i know a few people who do and they have only been able to tell me good things about them....

What are you revving the car to? anothing to consider is depending on how high you are able to revv the car you might actually be close to running out of gear in 4th...id think with the power/weight of the car you Should go atleast 150mph... so say you can only revv it to 9k youd be out of gear with a standard GSR trans + 24.5in tires... Edit : youd also be out of gear with the ITR trans even if it had the Mf 4.05 FD

Check out this comparason between a standard gsr trans and a gsr with MF FD/1st: http://www.teammfactory.com/gearcalc...ission+1+and+2

 

Thanks for that info, so I ll try the GSR trans with MFactory 1st gear and 4.05 final drive.

I rev the engine till 9300

 

Depending on what tires you use and what 4th gear you already have, I think you will be out of your powerband with GSR gearing and a 4.05 FD, that gears you down into the LS tranny range, if your going to use the 4.05 put it in the ITR gearset, first install a USDM 4th gear in it which will make it similar to GSR gearing, you can reach 150 with the USDM ITR gearing but you need almost 10k rpm w/o the FD change, with the 4.05 you should get over 150 at your current redline.

Or just get a GSR....lol

 

Without knowing the Setup, how do we know if he is out of his powerband?

 

my car with the ls tranny and shifting at 9500rpm from 3-4, it only drops to about 7000rpm.

 

I was mearly going by the 123mph in 3rd gear at 9300rpm with the geared down GSR tranny, he would probably be a good bit past the 1/8th before even hitting 4th gear. Most of the cars that I see going fast are in 4th at the 1/8th or just feet past it, our powerbands are generally high and peaky and hitting 4th just 2 or so seconds before the traps is not using all your gearing the way you should...... IMO

I should of used a different word other than powerband. but I dunno maybe I am thinking too much

 

hahaha maybe im not thinking enough ...

From the hondas that i have seen that do about 150traps they are pretty close to 120-123 1/8th mile traps... i know my friends car that goes 153 was doing 124 in the 1/8th...That being said with the power he has and the weight of the car it should go atleast 150mph... He would still have to upp the Revlimiter if he just used a gsr tranny to make the 150mph trap...

I guess he should also look into the future, if he does the MF FD/1st he will have some room to grow on if he ever decides to make some more power he will not be limied on how fast he could go...

 

Thanks guys for your help.

My power band seems a bit high. The power and torque are almost equal . The torque band is about 6800 rpm and it goes up till 8800 for sure.

The power band is almost the same but it still have power till 9100.

Since the car and engine were built ( this year ) I went once to the strip with the GSR trans and it seems that the gears are short, but I only tried it with drag radials ( so no traction ) and even I managed to damage completly the second gear and mainshaft also ( 2nd gear ).

That's why I m confused on what to install now

 

Any more ideas please