MV DJ difference

[fix]

Firstly ive tried to do the research before putting up a post,i know a couple of differences but want to make sure im not missing anything.

Im currently replacing gaskets on a 2.1MV as it was leaking coolant from one of the heads (thread in the alternative engines section).While im at it im thinking is it worth sourcing some DJ heads to give it abit more grunt,just an idea as it may work out too expensive sourcing some heads.

The engine will be run on the pierburg carb i already have so the injection system is not an issue.

Can anyone tell me other than the injection system is the only difference the heads? Is the bottom end as strong in the MV as the DJ?

I know the MV used a cat and had an lambda sensor which running with the carb will not be used.


Thanks

[kevtherev]

Firstly ive tried to do the research before putting up a post,i know a couple of differences but want to make sure im not missing anything.

Im currently replacing gaskets on a 2.1MV as it was leaking coolant from one of the heads (thread in the alternative engines section).While im at it im thinking is it worth sourcing some DJ heads to give it abit more grunt,just an idea as it may work out too expensive sourcing some heads.

The engine will be run on the pierburg carb i already have so the injection system is not an issue.

Can anyone tell me other than the injection system is the only difference the heads? Is the bottom end as strong in the MV as the DJ?

I know the MV used a cat and had an lambda sensor which running with the carb will not be used.


Thanks

the DJ employs higher compression pistons (112) so you get 9.5 to 1 from an MV and 10.5 to 1 from a DJ.
I think the rods are lighter on the MV.
Timing is different too

the DJ has Bosch Digijet injection... But the MV has digifant with combined fuel and ECU

heads are the same

[fix]

Cheers Kev so basically im best sticking as i am, the expense of buying new pistons alone outweighs the benefits and if the rods arent as stong on the MV its asking for trouble.

I think ill stick to the standard MV!

[kevtherev]

or get a DJ
plenty about.

[jed the spread]

drove both and the difference is noticeable.

jed

[jason k]

i've had both and find the mv the sweeter motor plus with the mv theres no need to run it on super unleaded, i know the dj can run on normal unleaded but the timimg is knocked back as is the power.

mv for me every time.

[ricicles]

which one was better jed?

[Aidan]

driven both and difference is pretty negligable and MV generally smoother drive
decat it and ensure exhaust is leak free for optimum fuel efficiency and driveability
if replacing lambda use only genuine bosch unit cheap ones from gsf don't work for long ime
MV has less of the older prone to failure bits like ignition amp and idle stab unit and is easier and cheaper to get new parts for like disi, have you seen the price of DJ vac unit !
DJ much more plentiful so easier to find used parts for in this country
stay stock is my advice, also bentley manual covers MV fully as do other web resources in english

[jed the spread]

which one was better jed?

In my case i drove a two vans both syncro dokas even the same colour. The Mv seems alot smoother to be fair but it lacks the grunt the dj has but it has been tuned to run on normal unleaded. I had to take a run up on a small hump were i would have been ok in the dj knowing its capabilities and on the road the Mv just seemed gutless. It felt like how id imagine driving a 1.9 petrol would be.

jed

[fix]

This thread has turned into abit of an mv dj debate!

I wont be getting a dj engine when i have an mv that seems in good condition, i just thought i might be able to do abit of tweeking.

Thanks for the advice Aidan,though I was thinking that the lambda sensor wouldnt need connecting as its been run on the carb so there will be no ecu,i assumed that would be ok?

Good to hear the mv is a smooth runner, and jed i currently have a 1.9 engine so im used to not getting anywhere fast

[Aidan]

The two syncros Jeds driven have different gearbox final drive ratios, so not quite like for like comparison, but the DJ is gruntier

[toomanytoys]

Mmm...
the only difference is the pistons.. (higher compression ratio on DJ) rods are the same on all wbx.. the rod bolts are different from 1.9 to the 2.1's.. (this is a weak link in the 2.1, but doesnt seem to affect 1.9's..)

If you are using the DG 2e3 carb, also use the DG distributor.. DO NOT use the MV distribtor.. Remove the Cat if still fitted in the exhaust too.. set up timing at 5-7 deg BTDC.. using 95 UL


ONLY DJ's need timing adjustment to 5 deg BTDC if using 95UL as they usually run 10 deg BTDC on 98UL..

[eatcustard]

ONLY DJ's need timing adjustment to 5 deg BTDC if using 95UL as they usually run 10 deg BTDC on 98UL..

Mine is set at 10 deg BTDC, and when Im not running on LPG I have had 95 ron in and found it to run the same as 98 ron.

[fix]

It would be nice to have dj power but i dont think its worth the extra money on new pistons,and buying 2nd hand ones is im sure a lottery.

Thanks for the advice ill make sure i use the 1.9 distributor when fitting the 2.1, it will be in the new year at some point once the engine is fitted.

I take it once the mv is run on a carb the lambda sendor will be totally redundant? I dont want to have emissions issues for the next mot!

[kevtherev]

I take it once the mv is run on a carb the lambda sendor will be totally redundant? I dont want to have emissions issues for the next mot!

hmmm
that's a good point
Doesn't your reg will bring up your vehicle with its engine and emissions values for that MV engine?.

perhaps someone can clarify this point

The CO value for MV is 0.5 % volume MAXIMUM... that's too weak a mixture for a carb (values courtesy of Brickyard info)

DJ.. CO content @ idle 2±.5 % volume