[Gasoline]

Dear friends,

I know there are few discussions / threads already here about Amby modifications. But still I feel this thread will be useful to the members who are interested in "ISUZU gear box change only" with all minor details and photographs and the cost part of the job done.

My Amby is a 1991 model with Matador engine + 4 gear usual gear box (column gear shift). Every time when I drive the car I felt this car needs an additional gear, because of the engine's powerful pick up and less speed by the gear ratio. So after inquiring to few of the auto lovers(in my town Amby lovers and Veterans are many) they suggested me to go for a Isuzu 5 speed gear box which will match with the matador engine nicely. Also the advantage will be fuel economy i.e. from 14 to 15 Km/Lit to 17 to 18 Km / Lit.

Then my next job was hunting for a good ISUZU gear box, ( and what I thought was, only a gear box is enough for the modification) luckily I had some known friends in Pudupet,Chennai and they were sourcing for me and finally I got the "piece" which was removed from a Contesa petrol car. I contacted my mechanic and told about the the availability, he advised me to buy all the related parts, which were

1. Clutch unit ( Diaphragm model)
2. Gear box mounting plate
3. Gear shift rod
4. Clutch engaging bracket with bearing
5. Drive shaft (the new model split ones)

All the above cost me 11,500 and the guy in the shop sent the items from Chennai to Kovilpatti (which is my native) though some transport system which cost another 500 INR.(So in total 12,000 INR is the cost)

So finally the Project started on 16th December 2008 and the work shop people promised me it will complete by a week maximum. You know what? It took nearly a month of chasing the people and I thought to myself "why the hell I started this project!!" . Since I read many members experience and the same line of hurdles they also came across, I consoled myself that "here things will happen like this only, so you have to adjust according to them".

The best part of the game is the mechanic ; he is a very good, knowledgeable, adjustable young man. Through-out the project, he answered all my queries, explained the job what he had done, and going to do, and above all he appreciated me for my enthusiasm.(generally in this field we don't find such good personalities)

1.First they started to strip down from the engine bay
(Then went to attend another car)
2.Once the strip down was over the new mounting plate was fitted with the engine, some of the mounting holes didn't match so it needed correction by milling.
3.After correction, the flywheel cavity for clutch, faced by the lathe work for the new clutch assy.
4.The bearing for flywheel was changed to new one.
5.The Gear box mounted on the mounting plate was not seated properly. The length of the gear box shaft was found to be little more than required and that was faced off.
6. Checked the clutch operation by hand with a help of a ring spanner. clutch bracket broken.(The pitty is vital spares wont available in my town. So the nearby town is Thirunelvelli - 60 Km) Ran to Thirunelvelli and purchased spare bracket, with new bearing.
7.Next day the clutch was set by the new bracket and clutch clearance ensured.
8.Now the gear box is not shifting and the mechanic told me we need another gear box, but i told him to try out something to make it work. He also tried and succeeded ( a big sigh of relief for me). I don't know what he had done but he told me the gear initially were wrongly over-ridden and after making some manual shifting it was cleared.

Next day. The gear box with the engine were tried on the car's engine bay, but the mounting plate is 1" inch wider on either side and does not fit in the chassis. We have already fixed a Tinker, who is one among the best in my place, but Murphy's law started working. The tinker met with an accident and he was not ready for another 15 days at least. My mechanic was not ready to compromise with any other tinker. So, we postponed for another 10 days and finally his son came to rescue after 15 days , he is also a equally talented guy.

So continues 4 days x 12 hours duty for the mechanic and tinker ( of course to me too ) the work completed.

See the photographs and tell me if any more work to be done.

Forgot to tell the cost of the project. It costs me around 25,000 INR to be precious the details are as follows.

Gear box,clutch,drive shaft,gear lever 11500.00
Spares 3820.00
Bolt,Nut,Washer 533.00
Transportation charges 570.00
Labour 9250.00

Total expenses 25673.00

Finally the speedometer (Veethree) is not working smoothly even after the necessary modifications done. So planning to go for a second hand one.

[Gasoline]

next 20 photographs, following to my previous posting.

[badboyscad]

@ gasoline : That is one clean detailed pictorial report on the gearbox change. how about adding a report on how the amby is running after the gearbox change?

[GTO]

Nice report. But you haven't spoken about any post-operation benefits. Does she drive better? How do you find the gear ratios matching to the engines characteristics?

Originally Posted by Gasoline

Since I read many members experience and the same line of hurdles they also came across, I consoled myself that "here things will happen like this only, so you have to adjust according to them".

Alas, our after-market is very disorganised and inefficient. What we wouldn't give for improved standards.

Total expenses 25673.00

That's quite a lot of money for a gearbox. We get used working Contessa gearboxes for 4,000 - 7,500 in Mumbai.

[kbalii]

Very well done. If the car is fully done you might wanna post pictures of the same. Take it for a spin and let us know.

The price of the gearbox is slightly on the steep end but as long as it does all its supposed to do, then it is completely worth it.

[Gasoline]

few more photos attached to my previous posting. If you see the photos you will understand the date of delivery from the workshop. The trials are found encouraging, i.e the noise of the car reduced to greater extend.The milage has to be checked by a long trip which is scheduled for tomorrow (here Pongal holidays are started and we planned to go for an outing) then you will get the updates.
Gear shifting is very smooth.
About the cost of the project too felt it is exceeded the planned cost, but I doubt it can be done with in 7000.Any way this is the cost which sucked out by the workshop guys and no point of feeling sorry.

[Gasoline]

Originally Posted by GTO

Nice report. But you haven't spoken about any post-operation benefits. Does she drive better? How do you find the gear ratios matching to the engines characteristics?

Regarding the gear ratio, honestly speeking I don't know. It all decided by the other car which is having the same features. But if any of our members know the details I will be happy.


Alas, our after-market is very disorganised and inefficient. What we wouldn't give for improved standards.



That's quite a lot of money for a gearbox. We get used working Contessa gearboxes for 4,000 - 7,500 in Mumbai.

You may be right, the gear box cost, would be around 7000 but is it only the gear box? or the spares including a new clutch,mounting plate,drive shaft,gear rod etc. Please clarify.

[prabhuav]

Has the gerabox change given you what you were looking for - Better mileage? This is a very popular mod in kerala and the number that I heard were more in the 10-15k range.

[im_srini]

Hi Gasoline, a series of nicely detailed posts. However, isn't cutting the transmission casing a bit extreme ?

Wouldn't using the starter from the Contessa, from whence you sourced the transmission, match perfectly without any cutting into of the transmission casing ?

I'm guessing the old gearbox would've offset some of the costs of the one from the Contessa, could we know how much it fetched ?

[Gasoline]

Originally Posted by im_srini

Hi Gasoline, a series of nicely detailed posts. However, isn't cutting the transmission casing a bit extreme ?

Wouldn't using the starter from the Contessa, from whence you sourced the transmission, match perfectly without any cutting into of the transmission casing ?

I'm guessing the old gearbox would've offset some of the costs of the one from the Contessa, could we know how much it fetched ?

I think the engine (Matador) plays the role for cutting the transmission body cutting, so the Contessa starter may not fit.

I just want to ensure the modification is working properly until then the old gear box will be with me, then yes, it will be sold.

[Gasoline]

Dear all,

After making a 400 km trip during the holidays the modification is justified by 17.5 km per liter of diesel.This is 300 kms straight run and 100 kms in traffic approximately. I think this info is pending from my side. Thank you all for your inputs.

[swathyd]

Dear gasoline , I have done the same transplantation for my ambassador matador. It was done on april 2007 . I too got the isuzu gearbox from a contessa petrol. It also had clutch unit , conversion plate , drive shaft etc with it . Had to do some welding for the drive shaft . And as you mentioned the odo meter is not working properly after the conversion , which i knew earlier . It owes to a mismatch between old differential housing and new gearbox . It can be rectified by simply putting a housing made for an isuzu gearbox . But it is difficult to find one.

I am in search of one such housing. I dont have any mileage benefits as i am running on old differential housing . After having the isuzu gearbox the power delivery is very smooth and different . Can overtake in 2nd and 3rd gear with ease .

[im_srini]

Originally Posted by swathyd

And as you mentioned the odo meter is not working properly after the conversion , which i knew earlier . It owes to a mismatch between old differential housing and new gearbox .

Hi Swathy, could you elaborate please ? As far as I know, this being a RWD & all that, the gearbox & differential are quite separate (by a few feet) & connected only by the prop-shaft. Or is the odo for the Amby driven all the way from the differential ?

Originally Posted by swathyd

It can be rectified by simply putting a housing made for an isuzu gearbox .

Surely, the Isuzu gearbox comes in its own housing...

Usually, the odo is driven from the gearbox output shaft. I'm guessing what's different is the gearing on the odo output between the old & new gearboxes - the revolutions of the odo output cable for a given distance are different.

[ramzsys]

here at coimbatore, i was offered a G1 with GB for 35,000.

[Gasoline]

Originally Posted by ramzsys

here at coimbatore, i was offered a G1 with GB for 35,000.

Please explain what is G1?