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Old 15th May 2009, 13:57   #16
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Default XD3P vs MDI3200 & MDI3200TC

Hi DD,

Here is how I look at engines

XD3P MDI3200 MDI3200TC
1) Weight - 190kgs 270kgs 300kgs
2) Displacement - 2498cc 2523cc 2523cc
3) Torque - 15.5Kgm 17Kgm 18Kgm
4) max Rpm - 42-4600 3200 3200
5) BHP - 73-76Bhp 58bhp 68bhp

I simply look at a Turbo as an air pump, which increases torque without significantly increasing the weight, and allows the engine to breathe better.

That is the reason they are very successful in the Himalayas.

For 2 vehicles with the same Gearbox/T-Case/Diff-Ratio and Tyres/Rims the vehicle with a higher RPM engine is faster (top speed).

Turbos definitely help a 4WD but, I don't think the small engine big boost types will help in reliability, a soft turbo with help breathe, clears emissions, increases the torque 10-20% is more than enough.

I dream of an XD3P with a soft turbo like the MDI3200TC .

Regards,

Arka
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Old 15th May 2009, 23:07   #17
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Originally Posted by ex670c View Post
Hi DD,

I dream of an XD3P with a soft turbo like the MDI3200TC .
I thought they did offer the XD3P Turbo in South Africa. Wish they would make it available here in India. It would be a perfect upgrade to the MM550.
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Old 15th May 2009, 23:51   #18
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Originally Posted by ex670c View Post


For 2 vehicles with the same Gearbox/T-Case/Diff-Ratio and Tyres/Rims the vehicle with a higher RPM engine is faster (top speed).
Yeah. That is why the MDI3200TC also has more low end grunt, desirable for 4x4 while the XD3P revs higher and is better on the hwy. I suppose.

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Originally Posted by ex670c View Post
Turbos definitely help a 4WD but, I don't think the small engine big boost types will help in reliability, a soft turbo with help breathe, clears emissions, increases the torque 10-20% is more than enough.
I was thinking mid size, not big. I do not want to have to stop and pick push rods and piston heads out of the trees after I gun it out of the slush. Don't want to frighten the animals.
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Old 16th May 2009, 11:07   #19
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Originally Posted by DirtyDan View Post


I was thinking mid size, not big. I do not want to have to stop and pick push rods and piston heads out of the trees after I gun it out of the slush. Don't want to frighten the animals.

how thoughtful of you!

Yes I agree a turbo is doable as long as the specs and install is done right.
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Old 16th May 2009, 12:09   #20
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Default Low End Torque vs RPM

Hi DD,

For 2 vehicles with the same Gearbox/T-Case/Diff-Ratio and Tyres/Rims the vehicle with a higher RPM engine is faster (top speed).

If you compare the M&M Major vs MM550XD vs CL550MDI

Kerb Weight -- 1300kgs 1400kgs 1300kgs
Torque -- 18kgm 15.5Kgm 16.5kgm
Engine RPM -- 3200 4200-4600 3200
Diff-Ratio -- 3.73:1 4.88:1 4.27
Crawl Ratio (Gearing) -- 39.45:1 47.85:1 41.86:1
Max Torque -- 710Kgm 741Kgm 690kgm

Similarly for the Trax Gurkha
OM616T TD 2650 FTI
Kerb Weight 1700kgs 1700kgs
Torque 19Kgm 18Kgm
Engine Rpm 3500 5400
Diff-Ratio 4.9:1 5.3:1/4.9:1
Crawl Ratio 45:1 48:1

Also though some of the engines have higher torque their lack of RPM, results in Higher Gear ratios, the result is lesser torque at the wheels or as Mr. Behram Dabhar explained Wheel Down Force, affects handling too.

This lack of RPM is evident in climbs, all the more in sandy terrain .

In a High RPM engine you can put Lower Diff-Ratio's and correct the wheel Speed with a Taller Tyre (Not Broader).

Regards,

Arka

Last edited by Rehaan : 17th May 2009 at 03:30. Reason: FONT etc tags removed.
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Old 16th May 2009, 14:12   #21
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This thread is all about increase the power of the engine..

Why not to consider the LPG Fumigation option than. It is quite simpler and can be good idea for not-too-hot climate (I guess). I am sure it will increase the power by atleast 10%. What do you think??

May check out the below thread..

http://www.team-bhp.com/forum/modifi...its-india.html

Last edited by DesertKing : 16th May 2009 at 14:13.
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Old 16th May 2009, 17:35   #22
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Quote:
Originally Posted by ex670c View Post

If you compare the M&M Major vs MM550XD vs CL550MDI
Crawl Ratio (Gearing) -- 39.45:1 47.85:1 41.86:1
Is the crawl ratio changed by the gears in the transfer case? so can we increase the crawl ration by changing the gears in the t-case?

Quote:
Originally Posted by ex670c View Post

Similarly for the Trax Gurkha
OM616T [FONT=Arial][SIZE=2]TD 2650 FTI
Kerb Weight 1700kgs 1700kgs
Torque 19Kgm 18Kgm
Engine Rpm 3500 5400
Diff-Ratio 4.9:1 5.3:1/4.9:1
Crawl Ratio 45:1 48:1
Arka, did you get the engines switched? I thought the OM616 was the high revving engine with slightly lower torque. The figures above suggest that the OM616 revs to only 3500 rpm and the FTI to 5400?

I think that maybe putting too much faith in Force to create an engine that can actually rev to 5400 rpm
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Old 18th May 2009, 10:12   #23
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^^ I agree. 5400 rpm doesn't sound right for a diesel of such kind.
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Old 18th May 2009, 11:13   #24
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Default Blunder!!!!!

Quote:
Originally Posted by 4x4addict View Post
Is the crawl ratio changed by the gears in the transfer case? so can we increase the crawl ration by changing the gears in the t-case?

Arka, did you get the engines switched? I thought the OM616 was the high revving engine with slightly lower torque. The figures above suggest that the OM616 revs to only 3500 rpm and the FTI to 5400?

I think that maybe putting too much faith in Force to create an engine that can actually rev to 5400 rpm
The Crawl Ratio in M&M Vehicle Changes with
1) Gear Box KMT90 (3.986:1) vs NGT520 (4.3:1)
2) Differential Ratio

DAMN!!!! I made a blunder .
1) OM616T = 90Bhp 18Kgm 4000Rpm
2) 2650FTI = 68Bhp 19Kgm 3500Rpm

The regular OM616 is rated at 4000Rpm MAX

Regards,

Arka

Last edited by ex670c : 18th May 2009 at 11:21. Reason: addl. info
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Old 19th May 2009, 03:41   #25
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Can the new bolero's CRDE intercooler and turbo be a direct bolt on onto the XD3P on the first gen bolero. If not how much will the engine cost approx for the CRDE one.
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Old 19th May 2009, 03:56   #26
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Originally Posted by hemanth.das View Post
Can the new bolero's CRDE intercooler and turbo be a direct bolt on onto the XD3P on the first gen bolero. If not how much will the engine cost approx for the CRDE one.
This is definitely not an easy task and not worth trying.
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Old 22nd May 2009, 18:52   #27
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Quote:
Originally Posted by ex670c View Post
Hi DD,

For 2 vehicles with the same Gearbox/T-Case/Diff-Ratio and Tyres/Rims the vehicle with a higher RPM engine is faster (top speed)........

...................
Also though some of the engines have higher torque their lack of RPM, results in Higher Gear ratios, the result is lesser torque at the wheels or as Mr. Behram Dabhar explained Wheel Down Force, affects handling too.

This lack of RPM is evident in climbs, all the more in sandy terrain .

In a High RPM engine you can put Lower Diff-Ratio's and correct the wheel Speed with a Taller Tyre (Not Broader).

Regards,

Arka
"their lack of RPM, results in Higher Gear ratios"

Arka, I take it you mean higher ratios as delivered from the factory?

Higher torque will turn a wheel with more power. Benefit is that it tends to free stuck wheels and is good starting up and overcoming resistance, e.g. hills.

Higher revs mean higher speed of a wheel turning. This will tend to keep a vehicle moving that is already moving.

Is this what you are saying? I am a little lost here.

There is probably a bell curve showing where the two concepts meet optimally. Is this covered in some other thread? I would like to know more about this. Just a little more. Behram, don't unsheath the slide rule on me, I am still using fingers and toes to count.

By the way, Dharamsala is at 1750 meters and I routinely go much higher than that. Turbo is handy to have up here. Cubic inches are good, too.

Last edited by DirtyDan : 22nd May 2009 at 18:56.
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Old 3rd June 2009, 22:35   #28
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Quote:
Originally Posted by DirtyDan View Post
"their lack of RPM, results in Higher Gear ratios"

Arka, I take it you mean higher ratios as delivered from the factory?

Higher torque will turn a wheel with more power. Benefit is that it tends to free stuck wheels and is good starting up and overcoming resistance, e.g. hills.

Higher revs mean higher speed of a wheel turning. This will tend to keep a vehicle moving that is already moving.

Is this what you are saying? I am a little lost here.

There is probably a bell curve showing where the two concepts meet optimally. Is this covered in some other thread? I would like to know more about this. Just a little more. Behram, don't unsheath the slide rule on me, I am still using fingers and toes to count.

By the way, Dharamsala is at 1750 meters and I routinely go much higher than that. Turbo is handy to have up here. Cubic inches are good, too.

Hey Dan,

What I gather from Arka's post is: For engines with high RPM/low Torque, they normally come fixed with lower gearing, the lower gearing compensates for the lack of torque (translates those RPMs from the engine into Higher Torque at the wheel).

Khan_Sultan did something similar on his gypsy, he addressed the high RPM/low Torque problem inherent in his gypsy by installing the crawler ratio in his gear-box. This now means he has a lot more torque to play with, but his top-speed has been cut down.

The same system in reverse can be applied to gain top-speed and economy in low RPM/high torque engines.

Ciao
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Old 4th June 2009, 08:41   #29
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Hey DD, Redmm340 has an old scorpio motor in his classic and he's building on reliability. Does that interest you?
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Old 4th June 2009, 11:42   #30
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Hey DD, Redmm340 has an old scorpio motor in his classic and he's building on reliability. Does that interest you?
Well, the motor does, yes. He had special adapter plates made and it took him 3 attempts at it before that worked. I'll PM you on this.
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