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Old 24th May 2019, 18:46   #106
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Re: Thar CRDe: Improving its low-end torque

Specifically in regard to the Thar CRDe, does anybody have any solid evidence that tweaking the exhaust produces more power? It stands to reason that if the engine has to expend less energy expelling exhaust gas out the tailpipe then the saved power goes to the wheels. But are exhaust mods really worth it?

Also, I got two quotes from two guys on Quantum remaps. One was for 24,000rp. The other was for 26,000rp. PLUS TAX. Does this sound reasonable in today's market?
The claimed gain is 21 horse power.
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Old 24th May 2019, 19:00   #107
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Re: Thar CRDe: Improving its low-end torque

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Originally Posted by DirtyDan View Post
Specifically in regard to the Thar CRDe, does anybody have any solid evidence that tweaking the exhaust produces more power? It stands to reason that if the engine has to expend less energy expelling exhaust gas out the tailpipe then the saved power goes to the wheels. But are exhaust mods really worth it?

The claimed gain is 21 horse power.
A free flow exhaust with stock map will not work. Infact you will lose low end torque.
Quote:
Also, I got two quotes from two guys on Quantum remaps. One was for 24,000rp. The other was for 26,000rp. PLUS TAX. Does this sound reasonable in today's market
The pricing sounds OK.
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Old 1st August 2019, 18:22   #108
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Re: Thar CRDe: Improving its low-end torque

On my December 2018 Thar CRDe which has just over 10,000km on it, I disconnected the Air Mass Sensor cable at the air filter AND blocked the EGR with a steel plate. The emissions light soon came on in my dashboard but it is NOT the CHECK ENGINE LIGHT and it is not bothersome.

The results are VERY satisfying. Instant horse power. I did something similar
to my 2013 Thar CRDe a year ago and also got great results. The EGRs of the two vehicles are different. My 2013 EGR just needed a little educated unplugging. However, my 2018 Thar EGR needed a plate to close off the EGR.

So, I had my somewhat trusted shade-tree Mahindra mechanic make me a plate and install it this morning. The whole business took about an hour and a half. In order to easily get at the EGR the mech took out the battery and the battery tray, the metal thing the battery sits in. He got into the bottom of the EGR and extracted the steel gasket found there. He used this gasket as a template to make a similar blocking plate. This was a little hard to install because the bottom of the EGR is hard to see, but the mech got it in ok.

The result was really good between the unplugged Air Mass and the blocked EGR. POWER!!! I am ecologically sensitive. I try to take care of the planet. But while the EGR seems to work well in eliminating some nitrous oxide from the environment on petro engined cars, it does not work nearly as well on diesels, according to a lot of experts on the web. In fact, the EGR on a diesel lowers fuel average and tends to dump abrasive particulates into the motor, decreasing engine life. I don't want to start a big debate over this here. If somebody wants to amplify on this, I am all ears, and eyes.

Anyway, I went with my best judgement and I am happy with the results so far.
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Old 1st August 2019, 18:47   #109
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Re: Thar CRDe: Improving its low-end torque

Super. I’m really glad that you solved the problem. The Thar CRDe really does have pathetic low end and this seems to solve the problem. And in what a margin!
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Old 2nd August 2019, 04:53   #110
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Re: Thar CRDe: Improving its low-end torque

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Super. I’m really glad that you solved the problem. The Thar CRDe really does have pathetic low end and this seems to solve the problem. And in what a margin!
Thanks so much for the good advice, Danushs. Mahindra made a correction to their ECU on the Thar in the latter part of 2018 that stopped the ultra slow acceleration. But the air-mass and EGR change really bring the performance of this 2018 Thar CRDe up to respectability. The changes really greatly increase the low end grunt of this vehicle, for sure, and without breaking the bank.

Last edited by DirtyDan : 2nd August 2019 at 05:07.
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Old 8th August 2019, 15:45   #111
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Re: Thar CRDe: Improving its low-end torque

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Originally Posted by DirtyDan View Post
SNIP*

Mahindra made a correction to their ECU on the Thar in the latter part of 2018 that stopped the ultra slow acceleration. *SNIP*
How do you folks come to know of such minute details when nothing is published? Wow!

So, if one were in the market for a used Thar, should one be looking only at late 2018 models then? Or, is this ECU mod doable (by authorised M&M service centres) on earlier (post 2015) models too?

Cheers
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Old 8th August 2019, 16:29   #112
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Re: Thar CRDe: Improving its low-end torque

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How do you folks come to know of such minute details when nothing is published? Wow!
All the old-timers in 4x4 section have half a dozen Mahindra guys on their speed dial.
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Old 8th August 2019, 18:51   #113
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Re: Thar CRDe: Improving its low-end torque

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Originally Posted by tilt View Post
How do you folks come to know of such minute details when nothing is published? Wow!

So, if one were in the market for a used Thar, should one be looking only at late 2018 models then? Or, is this ECU mod doable (by authorised M&M service centres) on earlier (post 2015) models too?

Cheers
You don't have to touch the ECU. Look at post #78 in this thread. Disconnect
the air mass sensor cable and unplug (close off) the EGR valve and you will suddenly have 18 % more engine, with immediate throttle response. Most Mahindra shade tree mechanics can do this for you. The difference in performance is astounding. A little yellow emissions light may come on in your dash, you can ignore it.

Oh! For the record, the CIA and Russian intelligence WISH they had our network.
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Old 22nd August 2019, 02:50   #114
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Re: Thar CRDe: Improving its low-end torque

Here are the fabbed up EGR plate, EGR gasket and EGR install of the blocking plate along with the old gasket. Works great.
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Thar CRDe: Improving its low-end torque-dsc02110.jpg  

Thar CRDe: Improving its low-end torque-dsc02112.jpg  

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Old 23rd August 2019, 13:46   #115
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Re: Thar CRDe: Improving its low-end torque

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The result was really good between the unplugged Air Mass and the blocked EGR. POWER!!!
Hey DirtyDan, I just tried this on my 2015 CRDe. I think it has the same EGR as the latest model. Earlier I disconnected just the MAF and the result was really good. However I reverted as there was too much smoke at low rpm.

Today I tried disconnecting MAF and also the vacuum hose to the EGR. The result was same but there less smoke at low rpm. I need to do a long drive to confirm this.

I wanted to understand why you put a blocking plate. I am under the assumption that removal of vacuum hose will keep the EGR valve shut and prevent exhaust gas recirculation. Correct me if I am wrong.
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Old 23rd August 2019, 14:38   #116
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Re: Thar CRDe: Improving its low-end torque

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Originally Posted by KA09_BIKER_GPER View Post

I wanted to understand why you put a blocking plate. I am under the assumption that removal of vacuum hose will keep the EGR valve shut and prevent exhaust gas recirculation. Correct me if I am wrong.
You may be right. I was going with what an "expert" told me.
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Old 24th August 2019, 13:35   #117
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Re: Thar CRDe: Improving its low-end torque

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Originally Posted by KA09_BIKER_GPER View Post

I wanted to understand why you put a blocking plate. I am under the assumption that removal of vacuum hose will keep the EGR valve shut and prevent exhaust gas recirculation. Correct me if I am wrong.
My mechanic is a guy who can do engine rebuilds upon occasion so he knows a little something.

I talked to him this morning about this EGR business. My guess is that your 2015 has the same EGR as the older original Thars. But he adamantly stated that the newer Thars do NOT have the same EGRs and must take a plate to block them off. Exactly where the distinction is time-wise between old and new EGR...I knoweth not.

Anyway, it cost me a whole 200 rupees to block it off and I am as happy as a clam about the results.
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Old 24th August 2019, 15:39   #118
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Re: Thar CRDe: Improving its low-end torque

Disconnect the vaccuum pipe and you will see some improvement in power, I triedthis for six odd months.
However I found it still weeps a thin black oil/vapour past the EGR valve. If you want a 100% block you need to fit a blanking plate.
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Old 27th August 2019, 15:45   #119
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Re: Thar CRDe: Improving its low-end torque

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Originally Posted by KMT View Post
Disconnect the vaccuum pipe and you will see some improvement in power, I triedthis for six odd months.
However I found it still weeps a thin black oil/vapour past the EGR valve. If you want a 100% block you need to fit a blanking plate.
I think the oil vapor is the oil from within the valve itself. There is a small piston which is used to close and open the valve which has some oil in it for lubrication. I couldn't figure out when when the EGR valve is disabled, this happens.

On my Ford Aspire, a blanking plate was used to close off the EGR after which the oil vapor was seen on the EGR end. Earlier to that when it had a plate with a hole in it and after that when I got it disabled in the ECU too, there was no oil vapor on it.

Also I am not sure if pulling the vacum pipe will result in fully closing of the valve as it can be stuck in open position too when the vacum pipe is disconnected. I had tried this on my car initially, but it went into limp mode.

Last edited by tharian : 27th August 2019 at 15:47.
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Old 27th August 2019, 16:01   #120
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Re: Thar CRDe: Improving its low-end torque

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Also I am not sure if pulling the vacum pipe will result in fully closing of the valve as it can be stuck in open position too when the vacum pipe is disconnected. I had tried this on my car initially, but it went into limp mode.
This is true. The better option is to just close it off physically.
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