Mahindra Marazzo: New MUV By Mahindra


Joined
Dec 1, 2011
Messages
3,155
Likes
2,036
Location
Pune
Over here buddy, it is about justifying the price point for the top spec M8 Vs the features it provides. I believe even though purpose of XUV & Marazzo are very different but the kind of price point that is provided to M8 Version, I find it overpriced. I feel more than Marazzo, XUV makes better sense as a VFM option. In my view, down the line, Sales of the Marazzo will get hit by the XUV and that's purely because XUV is better spec vehicle for the price it charges. Coming to TUV, firstly, it wasn't benchmarked to the top of the line SUV(s) like Endeavour or Fortuner. Secondly, TUV competes with the likes of Eco Sport, Nexon & Brezza none of which provide 4WD options so TUV not having 4WD isn't an issue. Instead, TUV should get a 4 cylinder mill in diesel like Eco Sport, Nexon and Brezza. Both Mhawk80 & 100 are 3 Cylinder mills. Lastly, if it is competing to the likes of Innova then in top model M&M should have given an AWD so that Toyota would have felt some heat w.r.t the fact that a MPV costing half the price of Crysta gives an AWD in top model where as Innova doesn't. That ways, Marazzo would have been a real challenge to Innova.
I beg to differ here Sir, to beat the Toyota what we need from home grown makers like tata/mahindra is bulletproof reliability, cheap service and long life ! There is a good reason, the good old DIs from Tata and Mahindra (read sumo and bolero) have had such a good long run! Apart from the facts they have to work on people's perception as well to change the image they have or beat Innova at its own game.

I am not saying or suggesting that M&M should give AWD/4WD in all variants of Marazzo. My point is if they had provided an option of AWD to the M8 spec then for sure, it would have competed much better to the XUV and to the likes of Ertiga and BR-V. Mind you, M6 & M8 are the only 2 variants which probably the personal buyers will look at. So, if not in M6 then atleast in M8 the features distribution should have been such that buyers should feel compelled for it.
I can tell you the next set of variants are already worked upon and options are on the table - however they will finalize once market feedback comes and depending on what the sales number dictate.

In the first place then, they could have benchmarked it with the likes of Ertiga & BRV. Benchmarking it against Innova and then planning to compete with it with an engine that is approx 900cc smaller to 2.4D of Crysta, not having an AT on launch, not having 4-to-6 airbags in top model isn't justified as per my opinion.

If FE & Emission is the concern then why give Scorpio & XUV bigger diesel engines of 2.2 Lt? Why not provide the 3 Cyl Mhawk100 1.5Lt engine to them? 1.5L might not be underpowered and may have a good performance but for the price M&M is charging why would anyone buy a 1.5 Lt engine when products from Mahindra's stable like Scorpio & XUV give bigger and better engines?
BS6 is round the corner and that changes everything - its an era of smaller engines and fancy emissions gadgetry - every manufacturer will go smaller engines (though i still like age old saying, there is no replacement to displacement - but i am old school and we need to respect modern era)

How can we assume that an option of AWD/4WD would have made Marazzo an inferior off-roader? If for example we take Hexa, it is an MUV or Crossover as you say, but has the provision of 4x4 made it an inferior off-roader? With my personal experience in Hexa Off-Roading, I can vouch for the fact that Hexa is an able off-road vehicle too. The reason people would have complained about the dull/poor performance of Marazzo @ off-road would have been due to the comparatively smaller engine. If it had 2.0L or 2.2L Diesel engine along with an 4WD in top version, it could have been a very capable off-roader frankly.

Regards

Akash
I wonder out of all the Hexas selling how many are AWD ! But that apart benchmarks for 4wd or awd will vary from person to person - an RFC guy will say nay to all stock vehicles despite whatever 4wd manufacturer hardware, whereas an entry level guy buying AWD first time might think this will rescue him from everything - so capability of 4wd and baseline of it varies a lot people to people. For me if you are buying 4WD buy a proper one - someone else would be happy with a XUV with AWD - but that's not me. So plenty of opinions here to respect - everyone will have one!
 

Nairrk

Honoured Member
Joined
Jan 16, 2016
Messages
14,659
Likes
5,274
Location
Payyanur/Kannur
Mahindra Marazzo Shark MPV gets featured in a new TVC – Toyota Innova Crysta rival

A new segment for Mahindra, Marazzo pre-launch marketing endeavours seem to have borne fruit. The company reported sale of 1,762 units pre-launch. With the exception of its Renault association, Mahindra has always had a special something for SUVs. The company has in the past let it be known it’s not interested in other passenger car segments.

The Marazzo is loaded with features like, a 7-inch touchscreen infotainment system with Android Auto connectivity, reverse parking camera, automatic climate control, cruise control, 17-inch machined alloy wheels, projector headlamps, cornering lamps, LED DRLs and much more. All these features are state of the art and will be carried forward to their upcoming SUVs along with part sharing, which will allow the the company save money.

mahindra-marazz-tvc-india-launch.jpg

Mahindra has gone for an aggressive pricing with their new shark-inspired MPV and hopes to grab a piece of the pie from Innova Crysta and Ertiga. The base variant M2 starts at Rs 9,99,000 (ex-showroom) and the top-end M8 retails at Rs 13,90,000 (ex-showroom). Mahindra is also offering numerous customization options, which customers may choose from to suit their taste.

The company has not classified Mahindra Marazzo as a MPV in popular speak but refers to it as a 7/8 seater family car. Available in diesel options, variant choices are as follows – Marazzo M2, M2 8Str, M4, M4 8Str, M6, M6 8Str, and M8. Below is the new Mahindra Marazzo Shark MPV’s TVC.

https://www.youtube.com/watch?v=tiBEO7UsXtg#action=share

For a car that measures 4585mm, seat placement doesn’t compromise in space. And while there are pilot seats, the seats aren’t quite as imposing as those seen in a Innova. A roof mounted AC outlet services both, 2nd and 3rd row passengers. Marazzo could in fact be a suitable choice for those who need to seat more than 4 people in their car from time to time, and it’s a budget car.

Only time will tell how successful is this new shark inspired MPV from Mahindra. Developed at an investment of Rs 1,400 crores, the Mahindra Marazzo platform is unique and will be used in upcoming cars from the company. Two of them are already confirmed, one is a SUV to rival Hyundai Creta, and other is a SUV to rival Toyota Fortuner.

Source:
 

Nairrk

Honoured Member
Joined
Jan 16, 2016
Messages
14,659
Likes
5,274
Location
Payyanur/Kannur
Mahindra Marazzo AMT in the works


Mahindra launched the Marazzo MPV on September 3, 2018 with just one engine and gearbox option. The MPV is available in four variants and two seating configurations. A few days ago, we reported that Mahindra will introduce the Marazzo petrol and automatic variants at a later stage, possibly around 2020 when the BS-VI norms kick in.

We can now confirm that Mahindra has begun work with Magnetti Marelli on development of the Marazzo AMT. The MPV will feature a six-speed AMT gearbox however it is yet to be known whether the Marazzo AMT will be available on the diesel, petrol, or on both engine options.

Currently, the Marazzo is available with a sole 1.5*-litre diesel good for 123hp and 300Nm, which delivers 17.3kpl under ARAI test conditions. The Marazzo takes on the likes of the higher variants of the Maruti Ertiga (soon to be replaced with an all-new model), the Toyota Innova Crysta and the Tata Hexa in the Indian market.

Source:
 
Joined
Sep 21, 2018
Messages
1
Likes
0
Location
Mumbai
The base M2 might appear unappealing at first glance; but if you look closer, it is the most value-for-money variant. It has all the basics covered, and Mahindra has introduced a long list of accessories that one could opt for to spruce-up the exteriors – like chrome highlights, alloy wheels and features like parking sensors and a music system.

So then, for little money over the base price, one could get all the essentials and some personalisation too, without really opting for the much pricier, higher variants. If you're after the best bang for your buck, the M2 is the one to go for; else the M6 is well-equipped and the feel-good factor you get is aplenty, for what it has on offer.
 
Joined
Aug 22, 2009
Messages
1,490
Likes
105
Location
Coimbatore
The base M2 might appear unappealing at first glance; but if you look closer, it is the most value-for-money variant. It has all the basics covered, and Mahindra has introduced a long list of accessories that one could opt for to spruce-up the exteriors – like chrome highlights, alloy wheels and features like parking sensors and a music system.

So then, for little money over the base price, one could get all the essentials and some personalisation too, without really opting for the much pricier, higher variants. If you're after the best bang for your buck, the M2 is the one to go for; else the M6 is well-equipped and the feel-good factor you get is aplenty, for what it has on offer.
M2 variant is about 5 lakhs cheaper than M8 in Tamil Nadu. It is priced below 10 lakhs, so attracts 10% road tax against 15% for all the higher variants. Since it gets Airbags and ABS as standard, it makes sense to buy the base variant and spend some money on accessories.
 

Nairrk

Honoured Member
Joined
Jan 16, 2016
Messages
14,659
Likes
5,274
Location
Payyanur/Kannur
Mahindra Marazzo: Fully accessorized MPV on video!

Earlier this month, Indian carmaker Mahindra launched the Marazzo MPV in India at a starting price of Rs 9.99 lakhs. At its launch, Mahindra revealed a host of accessories for the Marazzo which total over 100 different pieces. In the video below, Youtuber Ujjwal Saxena reveals some of these accessories for the Marazzo, which should be quite a hit with the Indian MPV buyer. In the video, Saxena heads to Koncept Mahindra, a dealership in Noida, Sector 2 to show off a host of accesories that have been fitted to a Marazzo being showcased on the showroom floor.

https://www.youtube.com/watch?v=eDL02xzFGCM#action=share

Up front the Marazzo sports chrome garnishing on its shark tooth grille along with a chrome bezel around the headlamps. The MPV also sports fog lamps which are optional extras for the lower spec variants. The fog lamps on the Marazzo can be fitted with thick chrome bezels to add to the shiny look that most Indians find rather appealing.

The front bumper also features add-ons that help protect it. These add-ons include a faux skid plate up front and can be painted in a dual tone shade as seen in the video or in the same colour as the rest of the body.

Moving to the sides, alloy wheels are an option for lower-spec variants of the Marazzo (they are standard equipment for higher spec models) and there are two options on offer 16 and 17-inches. The wheel arches can also be protected by bolting on the optional plastic cladding.

Other accessories on offer for the sides include chromed-out ORVMs and door handles along with the beading on the sides of the doors. The rain visors are available in black plastic or in a more chintzy chrome. Also available are side steps to allow for an easier entry into the Marazzo. The roof can also be wrapped in gloss black.

At the rear, there are more chrome garnishings around including those for the tail lamps bezels and at the bottom of the tailgate. Other chrome pieces include the section under the registration plate and the bezels for the reflectors. The rear bumper features protectors similar to the one on the front unit.

Step inside the Marazzo and there are more accessories on offer including scuff plates on the door sills and music system options including the top-of-the-line Tuscan music setup. Owners can also opt to add on rear parking sensors along with a rear video camera to their MPVs. Owners can also add tyre pressure monitoring systems and a tyre inflation system along with a car cover as well.

screenshot-www.cartoq.com 2018-09-27 08-52-37-349.jpeg

Source:
 
Joined
Sep 22, 2014
Messages
538
Likes
589
Location
m'bai, lko, kolkata
Since there is some apprehension about Marazzo engine’s adequacy.........By mounting the engine in front, M&M shaves off the transmission weight and reduces the inefficiencies associated with the RWD drive train.
The real concern should be the narrow turbo range of just 750 rpm (from 1750 to 2500) against, say, innova's 1400 rpm range (from 1400 to 2800 rpm). However by offering a 6th gear, M&M has ensured that even when hurtling down the highway, you can easily be within the turbo range of 1750 to 2500.........
That was certainly an interesting perspective. Mounting the engine in the front is standard practice, unless M&M offer a mid-engine (like many Ferrari exotics!) set-up or a rear-engine (like the 911 exotic from Porsche) set-up. Both these are out of M&M's ambit. If you mean the RWD set-up of the Innova/Crysta, there is nothing to suggest that this form of drive train suffers from any "inefficiencies associated with....". In fact the principal reasons for choosing RWD is durability, ruggedness & abuse-friendliness - which the Innova has amply demonstrated over the years. Unlike the Lodgy, Evalia, Style and other FWD wanna-be's in the segment, which have more or less sunk without trace! As I've said else-where, the major saving grace for the Marazzo is the hybrid body-on-frame structure which M&M seem to developed for this platform, while managing to cut down the kerb wt substantially, thus giving adequate specific power and specific torque figures.

And why do you say "the narrow turbo range of just 750 rpm...."? If I am right, what you mean probably is the crankshaft speed (1750 to 2500 rpm) for the optimum torque range. The turbo rpm range for small, high output automotive diesels is often in the range of 50K to 150K rpm and above.

And the 6th gear for the Marazzo is an overdrive ratio (as possibly the 5th gear ratio too, tho' I'm not sure, since I haven't seen the manual yet), and this is provided because the available torque from this splendid little engine is sufficient to handle the tall 6th gear ratio.

In fact if M&M had provided RWD in the Marazzo, I wouldn't have had a reason for not buying one.
 
Last edited:
Joined
Apr 29, 2017
Messages
277
Likes
261
Location
Chennai
If you mean the RWD set-up of the Innova/Crysta, there is nothing to suggest that this form of drive
train suffers from any "inefficiencies associated with....".
In the case of FWD vehicles, the torque path is direct to the wheels .On a RWD vehicle, the drivetrain additionally consists of the of propeller shaft, differential and drive shafts, which add inefficiency. The average RWD drive train efficiency is about 84%.
And why do you say "the narrow turbo range of just 750 rpm...."?
The turbo is almost always referred to in terms of engine rpm as there is no easy usable non-emperical relation between turbo rpm , the engine and car variables (beyond the vaguely empirical relation of 30 x engine rpm = turbo rmp). The narrow range is a concern because it is close to the Surge line (refer to the compressor map in this thread) . Surge line represents flow instability. Continued operation within the left of surge line region can lead to premature turbo failure.
Hexa too has the same 750 range, however since its Pressure Ratio is lower (due to higher capacity engine), it is in no danger of touching the Surge line even when staying within the efficiency region.
And the 6th gear for the Marazzo is an overdrive ratio (as possibly the 5th gear ratio too, tho' I'm not sure, since I haven't seen the manual
yet), and this is provided because the available torque from this splendid little engine is sufficient to handle the tall 6th gear ratio.
The 6th gear is definitely a overdrive gear but adding an extra gear is a serious engineering decision and increases cost of the vehicle, so it is not added just because torque is available. It is provided to reduce the rpm to turbo range at cruising top speed of 143 kmph because at this speed and at peak bhp rpm (3,500), the theoretical single gear Ratio works out to 3.164. ( Formula: Top Speed in m/s = Revolution Per Second / (Gear Ratio x Tyre Circumference in meter), so for 215/65 R16 tyre and 3,500 rpm, [3500/(GR*60)]*(0.6859 *Pi) = 143x5/18.
Solving for GR gives 3.164 ).
HTH
 
Joined
Oct 25, 2015
Messages
927
Likes
1,155
Location
BOM
TD Marazzo today.

Let me start with most important and waited question, What are it’s negatives :-

1) No 6 airbags on offer, ESP. With weird handbrake, Hill Hold is must. C’mon M&M even Ford FreeStyle comes equipped with it.
2) Few features missing here and there but nothing deal breaker IMO.
3) Fit and Finish is still not comparable with Germans but alot better than any M&M for sure
4) Pathetic ICE (except fluid to use HU)
5) Can’t reset FE from MID
6) Like Tata, M&M have capped MID to not show FE below 9 kmpl. So the least FE shown is 9 kmpl
7) No recline option for 3rd Row seats, it was a bit upright for my liking.
8) Engine booming can be felt. Hexa seemed more refined to me.
9) Firm suspensions can be felt at low speeds. Definitely not as plush as Hexa.
10) Clutch is long travel, due to which wasn’t able to adjust driver seat to my preference. But got used to it later on.
11) Clutch is springy, takes slight time to adjust.
12) Third didn’t felt as good as Hexa to me.
13) Horn sounds meaky
14) Weird handbrake is pretty bad to use. Needs two push to disengage
15) Boot does seem to go much high. Taller owners be careful

Now comes the positives :-

1) Bigger than my expectation, but not big like Crysta. I personally find it very practical for tight condition cities.
2) Initial braking bite is missing, but after that it’s strong.
3) Even under hard braking no nose dive. This is were Hexa and Crysta disappoints.
4) Quite stable at triple digit speeds and around the corners
5) Engine is more than adequate. Power comes in low rom and in linear fashion, perfect for an MUV/MPV. If behind performance get Crysta.
6) AC is super effective, very impressive
7) MID is equipped very well
8) Large windows and they do go 99% down.
9) Seats are good, and second row have good travel for to and fro adjustments.
10) Third row have individual reading lamps, too good.
11) Armrest and Comfortable doorpads are welcoming
12) Side mirrors do well job of visibility. IRVM can be a size big.
13) One-Touch seat tumble is boon.
14) Good GC
15) Roof/Head liner is same as new generation Tata, very premium quality.
16) Damed grab handles for all three rows are chunky to hold and felt good.

Others :-
1) Floor mats were hindering with my slippers while disengaging clutch.
2) TD vehicles and staff come directly from M&M, no dealership included. Fantastic, no sales promotions talk and unnecessary calls.
3) VR set-up. Simply phenomenal.
4) Call, email and sms updates. Can rely on JD Power stats. Once got a call when I was driving, they apologised and said, “Take Care Sir, Drive Safe”. Brownie points for it.

All in all great experience and car.
Keeping in view the price, many negatives are acceptable, few can be adjusted.

Note: Car is was driving had just completed run-in period and was due for service.
 
Last edited by a moderator:
Joined
Sep 22, 2014
Messages
538
Likes
589
Location
m'bai, lko, kolkata
In the case of FWD vehicles, the torque path......Top Speed in m/s = Revolution Per Second / (Gear Ratio x Tyre Circumference in meter), so for 215/65 R16 tyre and 3,500 rpm, [3500/(GR*60)]*(0.6859 *Pi) = 143x5/18.
Solving for GR gives 3.164 ).
HTH
Thank you carcommentator, for the above! .....“in case of FWD, the torque path is direct to the wheels”.... - does this imply a strong, rigid path as in the case of RWD beam axles? ...“the av. RWD eff. Is about 84%”...which seems terrific to me!
On the other hand, the pitfalls & abysses of FWD set-ups are well established. And the reason is simple - from an engineering point of view, a FWD arrangement is a bean-counter's solution and not the engineer's. A FWD set-up is easy to manufacture. The engine, clutch, G/B and undercarriage sub-assembly can be made very compact and the set-up lends itself perfectly for volume production! But.....it is not an engineer's solution. Good engineering practice warrants that the stresses and strains in a mechanical system - a car - should not be concentrated in one region, but distributed as much as possible to keep wear & tear low & prolong life & durability.
It does not take much imagination to visualize the stresses built-up when the FWD car is being driven at full steering lock and at max allowable torque - a situation common enough for me when climbing the steep hairpins (often 1:3 or even better with gravel & kaccha surfaces) of Uttaranchal. It is understood that for wheel articulation in all 3 axes (mandatory for FWDers) universal couplings or CV couplings at both ends of each half-shaft to the front wheels are necessary. But the stress concentration (during adverse driving situations as outlined above) on the front undercarriage assembly due to steering & engine torque remains disproportionately high in FWD vehicles. Therefore transmission efficiency – your odd notion that FWD efficiency is higher! – is not the criteria here. Otherwise, M&M and TMC, Toyota, BMW, & Mercedes would not have stuck to RWD for so many of their mainstream products. Durability & longevity, ruggedness & abuse-friendliness are the reasons. FWD was and remains the softer & easier bean-counter’s solution.

Now coming to your fears about crossing the surge line in small automotive t/chargers. The first thing to remember is that surging by itself is a common enough phenomenon during rapid fuel cut-off overrun periods. Surge will decay once the turbo speed finally slows enough to reduce the boost and move the operating point back into the stable region. This type of surge is relatively harmless & usually occurs during periods of “hooligan” driving. It can be reduced by having "air-dumping" provisions - a blow-off valve or a recirculating bypass valve where the airflow is recirculated back to the compressor inlet (this is not an EGR valve!).
The other kind of surging is under-load surging, which can be harmful. In after-market fitments (strap-on turbo charging!) it is often an indication that the chosen t/charger is too large (rotor inertia being high, which will also cause turbo lag) & this is usually caused by mis-matching an engine’s scavenging needs with the characteristics of the chosen turbo. In existing engines with OEM turbos, it is usually the result of very poor maintenance –dirty scavenge air filters, dirty compressor/blower impeller blades, dirty volute casing, dirty aftercoolers/intercoolers, if fitted. Secondary causes (which are more common) are usually associated with poor combustion – jammed, dripping injector nozzles, sticky exh/inlet valves etc. During my working life I have come across sudden instances of surging when three fuel injectors out of six got blocked suddenly due to failure of line filters, allowing impurities to do the damage further downstream.

It is almost certain that M&M have made no mistake in matching the turbo to the Marazzo engine & if, during the car’s lifetime, on-load surging occurs, it is poor maintenance on the owner’s part & not much else.

.......“The turbo is almost always referred to in terms of engine rpm as there is no easy usable non-emperical relation between turbo rpm , the engine and car variables (beyond the vaguely empirical relation of 30 x engine rpm = turbo rmp)"......
I think I’ll let the above remark pass – except to say that empirical remarks/conclusions have no real place in engineering discussions. I have worked with t/chargers all my working life & I have yet to come across any instance in the relevant literature where engine rpm is referred to as turbo rpm.
Also I think I’ll let pass your strange remark about the 6th gear overdrive ratio being “provided to reduce the rpm to turbo range”. This is not just strange, but incomprehensibly peculiar!
 
Last edited:
Joined
Apr 29, 2017
Messages
277
Likes
261
Location
Chennai
FWD was and remains the softer & easier bean-counter’s solution.
I have no differing opinion on that but we weren't discussing about stress and strain, just about efficiency of FWD (implying fuel efficiency).
I think I’ll let the above remark pass – except to say that empirical remarks/conclusions have no real place in engineering discussions.
True, which is why I emphasized that turbo rpm have no real value in relation to other variables ( Relevant part of my comment : ..as there is no easy usable non-empirical relation between turbo rpm , the engine and car variables...)
I have worked with t/chargers all my working life & I have yet to come across any instance in the relevant literature where engine rpm is referred to as turbo rpm
Not sure if you are trolling here,[roll] but if you genuinely think I was referring to engineering literature, and not to general discussions (including by engineers) of referring to turbo in terms of engine rpm, you obviously are wrong in your thinking! I also think it is not blasphemous that even in industry, they talk about turbo in terms of engine rpm, unless of course you are specifically talking about turbo themselves in isolation to other variables.
Also I think I’ll let pass your strange remark about the 6th gear overdrive ratio being “provided to reduce the rpm to turbo range”.
Not sure why you consider it 'strange'. In overdrive gear the driven gear is smaller than driver gear. The rpm will obviously reduce by the smaller factor. Eg in Nexon, the 6th gear ratio is 0.578:1, so if you are cruising at steady speed at say 3500 rpm and you shift to the overdrive gear (6th gear) the same speed will be maintained at 3500x0.578 = 2023 rpm.
 
Last edited:
Joined
Sep 22, 2014
Messages
538
Likes
589
Location
m'bai, lko, kolkata
I have no differing opinion on that but we weren't discussing about stress and strain, just about efficiency of FWD (implying fuel efficiency).

I was discussing the un-suitability of FWD for the Marazzo (purely my opinion, I must add[:D]) and not fuel efficiency

True, which is why I emphasized that turbo rpm have no real value in relation to other variables ( Relevant part of my comment : ..as there is no easy usable non-empirical relation between turbo rpm , the engine and car variables...)

I must beg to differ. Turbo rpm & turbo efficiency is inextricably linked to all engine variables (state of scav. air line filters, state of inter & after cooler cleanliness, condition of fuel injection equipment, condition of turbine & blower impellers, turbo volute casing etc ) that affect the scavenging & combustion process. Current state-of-the-art turbos have efficiencies touching 80%. But this efficiency is very fragile - and is easily, drastically affected by changes in the variables mentioned above.

Not sure if you are trolling here,[roll] but if you genuinely think I was referring to engineering literature, and not to general discussions (including by engineers) of referring to turbo in terms of engine rpm, you obviously are wrong in your thinking! I also think it is not blasphemous that even in industry, they talk about turbo in terms of engine rpm, unless of course you are specifically talking about turbo themselves in isolation to other variables.

In industry - at least the shipping industry - where I spent my working life & which lives & breathes t/chargers as a normal way of life - no one in his right senses talks about turbos in terms of its
associated engine rpm.


Not sure why you consider it 'strange'. In overdrive gear the driven gear is smaller than driver gear. The rpm will obviously reduce by the smaller factor. Eg in Nexon, the 6th gear ratio is 0.578:1, so if you are cruising at steady speed at say 3500 rpm and you shift to the overdrive gear (6th gear) the same speed will be maintained at 3500x0.578 = 2023 rpm.
Overdrive is provided only to utilize the available torque from the engine, which allows taller gearing (driver larger than driven, in your words) without sacrificing drivability at higher cruising speeds, thus adding to F.E. at highway speeds. It is not provided to reduce engine speed to bring it in line with turbo speed.
 
Last edited:
Joined
Apr 29, 2017
Messages
277
Likes
261
Location
Chennai
Overdrive is provided only to utilize the available torque from the engine, which allows taller gearing (driver larger than driven, in your words) without sacrificing drivability at higher cruising speeds, thus adding to F.E. at highway speeds. It is not provided to reduce engine speed to bring it in line with turbo speed.
As regards FE, I know where you are coming from. In 1970s and 80s,in many cars, Overdrive gear was an add-on and came separately in a unit which was attached to the main gear assembly. It was solely used to reduce rpm at cruising speed by using a physical shift lever mechanism. However, now all cars have the overdrive gear incorporated in the main gear assembly so overgear use is not restricted to just improving FE.
I agree that overdrive reduces rpm at cruising speed and thus increases FE. I have shown that in Nexon overdrive gear calculation in comment above.

However, your contention that "Overdrive is provided only to utilize the available torque from the engine" is debatable.
Marazzo has peak bhp of 121 at 3,500 rpm. Let's see how much Torque is there at this rpm.
Torque = bhp X 5252/rpm = 121x5252/3500 = 181.56 lb /ft = 246.16 Nm.
To avail this torque at 3,500 at cruising speeds of 100 to 140 (the max speed of Marazzo is 143), the Gear Ratio required at various speed from 100 to 140 in increments of 10 kmph :
[3500/(gr*60)*(0.6859 *[Pi]) = Range[100, 140, 10]*5/18}]
3500 is the rpm at peak power, 0.6869 is tyre diameter in meters, 5/18 is used to convert kmph to m/sec.

Solving for gr (gear ratio), we find that the single gear ratio required at various speed are:
100 kmph -> 4.52512, 110 kmph -> 4.11374, 120kmph -> 3.77093, 130kmph -> 3.48086 and 140 kmph -> 3.23223.
As you can see there is no need for an overgear to avail of the torque.
HTH
 

Top Bottom