[MalluDude]

If you were plannning buy a used diesel jeep in Kerala, the first question someone will ask you if you're looking at a "hi-speed" or a "low-speed" model.

Now from what I hear, this's got nothing to do with the running speed of the jeep, but rather it's engine. I am told that jeeps manufactured prior to 1990 had low-speed engines, and after that they came with high-speed engines. The main difference being in their engine heads and the fuel pumps.

Now note that this is different from the 2112 cc Peugeot engine on MM540.

Jeeps with low-speed engines supposedly give you low fuel average, and are available for 50-65K, whereas the high-speed equipped ones upwards of 90K. (I am talking about 4x4 models. 2wd's could be had for 10-15k less)

The reason I'm posting here is I am yet to come across a discussion in T-bhp about these two types of engines. Could someone please confirm what I've mentioned above? If it's really true does anyone know the actual specs of the these two types of engines? Apart from the fuel efficiency aspect, are there any advantages of one over the other?

If this has been posted before, could you get me that link?

Thanks, Nitin.

[4x4addict]

Nitin:

Setting aside the 2112cc mm540 and the 2.5 Liter mm550xdb/bolero engine, most CJ500s it's cousins come with the International engine. I am not sure about this highspeed/lowspeed talk but I suspect it is just local lingo for different versions of the engine. The international initially came in an Indirect Injection form. These have low power and decent mileage. Mahindra subsequently launched a DI version and then added a Turbo the DI version. I suggest stick to the Di engine or DI turbo engine cause the earlier ones i.e IDI engines are a real slouch that barely makes 35 bhp or something like that.

[DHABHAR.BEHRAM]

Dear Malludude - the whole story is as follows:

It all started in 1973 with the fuel prices. Petrol was 1 rupee a litre, it became 3 rupees a litre overnight. In those days, M&M used to make petrol Jeeps. There was an immediate need to make diesel Jeeps. After trying various options, the vehicles finally got an engine known as the "MD2350". MD means Mahindra Diesel and 2350 was the maximum engine rpm. The original petrol engine was a relatively high revving engine as compared to the MD2350, so the axle ratio was changed from 5.38:1 to 4.27:1. Even with 4.27:1, the official maximum speed of this vehicle was 72 kmph. Subsequently, in the interest of fuel economy and startability, the MD2350 which was an IDI engine (indirect injection) was converted to a DI (direct injection) engine. Its peak rpm was increased to 2500 and it was known as the MDI2500A. This engine became very popular as it used to deliver fantastic fuel economy. Customers were achieving 17 / 18 kmpl under actual use condition. Then came the 1996 emission (pre BS1) norms which necessitated a further changeover. The engine became MDI3000. The vehicle speed increased a little but the fuel economy was not as fantastic as before, although 15 kmpl was quite achieveable. Further development led to the MDI3200 and then the MDI3200TC (turbo charged). This is a soft turbo introduced for meeting the stringent BS3 emission norms. Today's vehicles run on a 3.73:1 axle ratio. The engine is extremely reliable, very easy to maintain with all spare parts easily available.

This is what is meant by "low speed" and "high speed" in local parlance.

Best regards,

Behram Dhabhar

[4x4addict]

Dear. Mr Behram,

Could you explain how the the MDI3200 TC in the Scorpio make 70 bhp? Is it by addition of any intercooler and adjustment of Fuel pump? I have the MDI3200 TC in my 540 and would like to bump up the power to match the Scorpio M2DI spec if it doesn't require any major mods.

[vinod_nookala]

Behram sir,

What is the official top speed of MM540 4wd and what is it for 2wd with standard 6.00 16 tyre? Iam asking you this as there were no magazines then to record true top speed of these vehicles.

Further please tell me -
when both XDP and XD engines rev upto 4000+ rpm and both run on 4.88 axle ratio, then why is there a difference in top speed of vehicles equiped with these engines? In my opinion there should be a difference in time to achieve top speed in 4th gear but why is there a difference i top speed?

(here i have assumed both xdp and XD engines are redlining at 4200 rpm in 4th gear)

off road- i feel there is hardly any difference between the capability of engines as i havent felt any time- 'wish i had more horses or torque'. There should be a reason why M&M upgraded the engine to XD 3p. Please enlighten!

[Torque-ative]

Wow,..that answers a lot of questions on what the 3200 after the MDI stands for. We are indeed honored to have such legends such as Mr.Dhabbar in our midst.

[DHABHAR.BEHRAM]

Dear 4*4 addict - the engine characteristics are different. I cannot share further information.

Dear Vinod - XDP4.90 and XD3P are from the same family. The XD3P has more power so it can be made to operate to meet a stricter norm. I cannot share further information.

Best regards,

Behram Dhabhar

[DirtyDan]

Originally Posted by 4x4addict

Dear. Mr Behram,

Could you explain how the the MDI3200 TC in the Scorpio make 70 bhp? Is it by addition of any intercooler and adjustment of Fuel pump? I have the MDI3200 TC in my 540 and would like to bump up the power to match the Scorpio M2DI spec if it doesn't require any major mods.

I do not know the anwer to this. But, I would not be surprised if they have different fuel pumps and different injectors. Maybe you can smooze with a Mahindra dealer parts guy? Make him an offer he can not refuse?

Different injectors alone could give you some power but I do not know if there are any viable alternatives to the stock injectors in India.

Change the fuel delivery and you start getting into complexities such as air/fuel ratios and their control. This is true of putting in a bigger turbo also.

[MalluDude]

thanks Dhabhar saab and 4x4addict. So that clears up things about the engines.

@4x4addict, yes I understand the IDI engine is a slouch, with very low bhp figures, but the reason I would prefer it right now is it's reportedly very reliable, and it fits my budget too.

[Ashley Nair]

Dear Malayali, stick to MDI 3000. It is far more fuel efficient and torquey than the IDI and it's available for Rs 25,000 at Pala Bazar, Kottayam

[DirtyDan]

Originally Posted by DHABHAR.BEHRAM

Dear 4*4 addict - the engine characteristics are different. I cannot share further information.

Dear Vinod - XDP4.90 and XD3P are from the same family. The XD3P has more power so it can be made to operate to meet a stricter norm. I cannot share further information.

Best regards,

Behram Dhabhar

Translation. He will not guide you in totality. That's ok. I hear his company is transfering him to marketing anyway.

[4x4addict]

Originally Posted by MalluDude

@4x4addict, yes I understand the IDI engine is a slouch, with very low bhp figures, but the reason I would prefer it right now is it's reportedly very reliable, and it fits my budget too.

They are very low-tech and extremely reliable engines. Drive it first and if you are okay with the power go for it.

Originally Posted by DirtyDan

Translation. He will not guide you in totality. That's ok. I hear his company is transfering him to marketing anyway.

I hope this statement is true, cause we wills see some true off-road vehicles from the Mahindra stable :-).

[supercars]

Originally Posted by 4x4addict

I hope this statement is true, cause we wills see some true off-road vehicles from the Mahindra stable :-).

Marketing Guys can never influence which Models will be produced.
If anything then the Off Road capability of all SUV will be lost in the Near Future as everyone will make a Soft Roader. You really do not want to jump in every city pothole do you ?

[IronWolf]

Originally Posted by vinod_nookala

In my opinion there should be a difference in time to achieve top speed in 4th gear but why is there a difference i top speed?

(here i have assumed both xdp and XD engines are redlining at 4200 rpm in 4th gear)

off road- i feel there is hardly any difference between the capability of engines as i havent felt any time- 'wish i had more horses or torque'. There should be a reason why M&M upgraded the engine to XD 3p. Please enlighten!

I just love that last line of yours. Always wondered why everyone only want 550s as if the 540 is a lesser capable offroader.

The only plus I feel is the 5th gear and slightly better power for the highway.

Originally Posted by DirtyDan

Translation. He will not guide you in totality. That's ok. I hear his company is transfering him to marketing anyway.

Nice take on it. Dont get him in trouble.

Originally Posted by supercars

Marketing Guys can never influence which Models will be produced.
If anything then the Off Road capability of all SUV will be lost in the Near Future as everyone will make a Soft Roader. You really do not want to jump in every city pothole do you ?

Actually he would be able to convince them to build a Short Chassis Wrangler like rip off which would sell pretty well in India.

New age Classic maybe? with the CRDi engine et all

Do you know how much a classic second hand sells for?

[4x4addict]

Originally Posted by DHABHAR.BEHRAM

Subsequently, in the interest of fuel economy and startability, the MD2350 which was an IDI engine (indirect injection) was converted to a DI (direct injection) engine. Its peak rpm was increased to 2500 and it was known as the MDI2500A. This engine became very popular as it used to deliver fantastic fuel economy. Customers were achieving 17 / 18 kmpl under actual use condition. Then came the 1996 emission (pre BS1) norms which necessitated a further changeover. The engine became MDI3000.

Behram sir, do you know which year the MDI2500A was introduced? I am in the market for a used jeep and want to stick only with the DI range.