Atr gear box

fithotblonde · Post by **fithotblonde** » Wed Apr 04, 2018 9:54 am

Hi every one i am looking at getting atr gear box. But i all ready have a m2b4 i think it is the lsd one out of a 4th gen. So my question is wich is better/ would you proffer thanks for help
Blonde

Post by **Drax** » Wed Apr 04, 2018 10:49 am

ATR gearbox is better, shorter ratio gears and better LSD apparently.

sol-lude · Post by **sol-lude** » Wed Apr 04, 2018 11:14 am

that 5th gear though

Speaking of the ATR box's, looking for some info based on what you have just mentioned. Im not sure which lude box I have in mine will see if I can find the sticker. Although I have been toying with keeping the Lude box in when doing the A7 conversion due to 5th gear being kaput. Is it possible to transfer over the 5th gear into the ATR box from the lude?

hondaddict · Post by **hondaddict** » Wed Apr 04, 2018 12:37 pm

About the 5th gear tranfert, yes it is possible

Free Ranj Egg · Post by **Free Ranj Egg** » Thu Apr 05, 2018 10:22 am

It all depends on what you are after mate. I am no expert but the 1st, 2nd and 3rd from a lsd lude box is shorter ratios and 4th and 5th are taller making it a better cruiser.

When I changed gearboxes from the M2P4 (standard a8 gearbox) to the M2B4 the drive did definitely change. In the non lsd M2p4 box I was able to sit in 5th at 30 mph but in the lsd box sitting at 30 can be funny if the speed slightly drops meaning I have to change down a cog.

I do a lot of motorway cruising from Brum to London so for me the lude LSD box is better. I have heard (someone will correct me if I am wrong) that the ATR gearbox is more shorter rations so on a cruise at 70mph it will sit at around 4k revs.

The lude Lsd Box sits at 3200-3300 rpms at 70. I think the ATR box may be slightly more aggressive too.

Hop this helps

Ranj

Post by **Vtecmec** » Wed Apr 11, 2018 10:38 pm

The atr box has the lowest ratios of each of the gears available in h22 gearboxes. I split mine open and fitted the 5th gear from a 2.0 box, which is really long. Fitting was not straight forward as I had to skim about 9mm off the collar that sits on the cog, in theory it should now sit at 3,200rpm at 70, though its still sat in the garage waiting for me to fit it.

sol-lude · Post by **sol-lude** » Thu Apr 12, 2018 9:44 am

Vtecmec wrote:The atr box has the lowest ratios of each of the gears available in h22 gearboxes. I split mine open and fitted the 5th gear from a 2.0 box, which is really long. Fitting was not straight forward as I had to skim about 9mm off the collar that sits on the cog, in theory it should now sit at 3,200rpm at 70, though its still sat in the garage waiting for me to fit it.

woaw that's really low RPM for 70mph should run a dream on the motorways.

Post by **Merlin** » Thu Apr 12, 2018 9:45 am

The ATR gearbox (same as the H22a8 box but it has a Torsen LSD) will be much better. The ratio's are better for daily driving in town and also allow faster acceleration. Plus the LSD is much better than the viscous LSD in the M2B4.

Yes the 5th gear in the ATR is a bit shorter and as a result you'll cruise at slightly higher RPM but 5th gear acceleration is faster! So it totally depends on what you'll be using the car for. In my 4th gen I have the M2F5 (with modified final drive) with an even shorter 5th gear.

Jackson Bondy · Post by **Jackson Bondy** » Thu Apr 12, 2018 11:20 am

Vtecmec wrote:The atr box has the lowest ratios of each of the gears available in h22 gearboxes. I split mine open and fitted the 5th gear from a 2.0 box, which is really long. Fitting was not straight forward as I had to skim about 9mm off the collar that sits on the cog, in theory it should now sit at 3,200rpm at 70, though its still sat in the garage waiting for me to fit it.

Is the final driver shorter on the 2.0 then as mine seems to cruise at about 3700rpm at 70mph?

Post by **Vtecmec** » Thu Apr 12, 2018 11:31 am

Its a 4th gen box, M2J5, which has a longer 5th than the 5th gen 2.0 boxes.

Some good info here.....

https://honda-tech.com/forums/honda-pre ... t-2548441/