Ztt 160 2.5 V6

[Tricky160]

Having read a thread on org, I have a question for the Guru's!

I have had my 160 for about 10 weeks, and love it. I am not certain if it is as quick as it should be?

It may just be me being fussy as I have driven some quite fast cars in the past.

It pulls really well 4000 revs and above but does seem a little sluggish below this. I am trying to drive it conseratively, so again it could be me, but I am typically only getting 22-23 mpg.

I have seen mention of vis valves, but dont know if my questions suggest this or not? Is there any way of knowing if I have problems?

I keep looking for another ztt160 2.5 to challenge to see how I do!

[Phil]

any tapping or clicking from the inlet manifold? How many miles has it done?

[Tricky160]

any tapping or clicking from the inlet manifold? How many miles has it done?

Just Done 70000, I have done 3000 of those. Havent noticed a tapping, or clicking

[Tricky160]

Come on Guys, I thought this was the nerve centre of all things technical, especiallt to help numpties like me

[Simon]

A few people are saying that the VIS valves aren't operational on the 2.5litre V6 because it is de-tuned 190.

I need someone to definately confirm/deny this, though.

Other thoughts could be simple things like in need of a good service (ie, oil change and air filter, etc).

I too drive a 2.5litre V6 and to be honest, I'm quite impressed but I have not driven anything more powerful in a while. Must try my mates 1.6 Civic Vtech (the Japanese SiR II spec one) coz that's stripped and goes link stink off a shovel.

[Tricky160]

A few people are saying that the VIS valves aren't operational on the 2.5litre V6 because it is de-tuned 190.

I need someone to definately confirm/deny this, though.

Other thoughts could be simple things like in need of a good service (ie, oil change and air filter, etc).

I too drive a 2.5litre V6 and to be honest, I'm quite impressed but I have not driven anything more powerful in a while. Must try my mates 1.6 Civic Vtech (the Japanese SiR II spec one) coz that's stripped and goes link stink off a shovel.

I was driving an 02 plate an M3 a year ago, so most things feel a little slow!

[Simon]

I was driving an 02 plate an M3 a year ago, so most things feel a little slow!

Well, yes. an M3 is a fair bit quicker than a ZT160. ;)

I'd like to think the ZT/75 is more of 'gentlemans' car. It doesn't have to be the fastest out there because you know that driving it is the best driving exerience out there.

If your car has been serviced and everything is up to scratch so far as you know then it'd be safe to assume the engine is running fine too. Keep an eye out for things like leaking coolant levels, that knocking sound that could indicate a failed VIS motor and things like that.

You can also try putting some Millers DPP in the fuel tank with your next fuel stop to help clear out any gunk in the cars system.

[Tricky160]

Well, yes. an M3 is a fair bit quicker than a ZT160. ;)

I'd like to think the ZT/75 is more of 'gentlemans' car. It doesn't have to be the fastest out there because you know that driving it is the best driving exerience out there.

If your car has been serviced and everything is up to scratch so far as you know then it'd be safe to assume the engine is running fine too. Keep an eye out for things like leaking coolant levels, that knocking sound that could indicate a failed VIS motor and things like that.

You can also try putting some Millers DPP in the fuel tank with your next fuel stop to help clear out any gunk in the cars system.


Thanks for the advice - couldnt agree more about the cars, The m3 was an animal, but I prefer the ztt, its more comfortable, sounds as good and has slowed me down considerably to ensure I will see my children the next day

[MartinW]

A comparison with a manic 4 cyl V-Tec does not hold water! :) The V6 is a gruntier engine.

There is another thread going currently on the engine upgrades entitled "Squeezing more power out of" or similar.

Simon, my source of info on the VIS is Roger Parker, Tech Officer at the MGOC, and Rincewind (ex-MGR) seems to concur by saying that loading a 177Ps engine map from a 75 will activate the VIS.

Ok, in Tricky's first post he describes the classic symptoms I have suffered at times. I noticed my problem back at 37k miles (Jan 2004), not long after B&G had serviced the car and loaded an updated map from MGR. Compared to previously, the performance was less pronounced IMHO, as peak torque seemed to have dropped from 3700 to 3000rpm, although this was meant to be an improvement on fuel economy. I also noticed, though, that when I floored the throttle in lane 3, it sometimes missed slightly. I went to my local dealer and they had the car overnight, and said they had replaced a valve, which I assumed to be the VIS at the time. The same scenario happened at 57k miles and again the local dealer had the car overnight and apparently replaced the other valve under warranty (about a week before MGR's collapse). I now wonder if there was any work done at all, or whether they effected a simple cure such as I later discovered myself.

However, late last year I noticed that mine was incredibly sluggish below 3000rpm. I had started reading about the oil problems and heard that this could foul the sensors. I bought some carb cleaner and with the inlet box removed, and the engine idling, I sprayed it into the plenum and let the engine idle for a while - I gave it a very good clean. This seemed to do the trick and the car was immediately a lot more responsive again.

As to adding anything to the fuel, this is maybe helpful in cleaning the injectors, but the real problems lie upstream of the injectors, hence the carb cleaner stunt.

I seriously recommend a good quality fuel like Shell's V-power, and give it a few tankfuls to clean up properly before expecting any improvement - in fact you won't notice an improvement so much as noticing when you do use the odd tank of unleaded - sparkle is lost!

I use a fully synthetic oil which is also known to have a better lubricity than semi-synthetic so this has a very, very small benefit, too.

Then there are my mods to the inlet and the back box (see my signature).

All this is never going to make the 160 hugely powerful, but it will feel more responsive, plus the engine seems to perform better if you give it a bit more heavy right foot as the ECU seems to adapt. And as said, fitting the 75's map might activate the VIS, if it is inactive, but I have to say I suspect it is not used just judging by the lack of noticeable difference in pulling through the revs to the redline. Having compared it to a 190 there is noticeably more at the top end where the 160 seems to just get breathless instead.

[JP53]

Having read a thread from the dark side, I have a question for the Guru's!

I have had my 160 for about 10 weeks, and love it. I am not certain if it is as quick as it should be?

It may just be me being fussy as I have driven some quite fast cars in the past.

It pulls really well 4000 revs and above but does seem a little sluggish below this. I am trying to drive it conseratively, so again it could be me, but I am typically only getting 22-23 mpg.

I have seen mention of vis valves, but dont know if my questions suggest this or not? Is there any way of knowing if I have problems?

I keep looking for another ztt160 2.5 to challenge to see how I do!

Part of the problem is how smooth the car is, it feels like it is going slower than it is. 70 mph feels a lot quicker in my wifes ZR than it does in my 75 :D

[Tricky160]

Part of the problem is how smooth the car is, it feels like it is going slower than it is. 70 mph feels a lot quicker in my wifes ZR than it does in my 75 :D

I agree and had thought of this, thanks to Martinw as well

The other thing I forgot to mention, and dont know if this is common in the 160's or not - 80 mph, motorway, incline, foot flat to the floor in 5th and still losing speed!

[Tatts]

I bought some carb cleaner and with the inlet box removed, and the engine idling, I sprayed it into the plenum and let the engine idle for a while - I gave it a very good clean. This seemed to do the trick and the car was immediately a lot more responsive again.


This sounds very interesting! Possible preventative maintenance, and a possible cure for a sticking valve.

Any chance please of a detailed how to?

[Simon]

A comparison with a manic 4 cyl V-Tec does not hold water! :) The V6 is a gruntier engine.

Yes... I quite realise this! ;)

I was using it as a point of reference regarding driving a quick car. Would always choose my V6 over a 4-cylinder now. Anything I drive in the future would have to have at least 6 cylinders now! :D


As for the engine upgrades:-
I agree they wont see much performance benifits but the resonsiveness is what I'm after too. I feel I should be able to put my foot down and feel the car 'take off' (even if it might actually not be all that much quicker on a rolling road).

I'll pop down to the local autostore and get me some carb cleaner and as mu fuel is almost on the red-line I'll visit my Shell garage to see what a few tanks of Optimax or V-power will do over time.

Don't know what the oil is in the car at the moment. Will ask the garage tomorrow whom I got the car from. Being ex-MGR I'd hope they'd use good stuff.

[MartinW]

Yes... I quite realise this! ;)

I was using it as a point of reference regarding driving a quick car. Would always choose my V6 over a 4-cylinder now. Anything I drive in the future would have to have at least 6 cylinders now! :D



:D I must admit, I, too, would dread the day I have to go back to 4 pots! Having said that, and as mentioned above, my wife's Rover 214 16V (105PS) feels decidely quicker at times, but I suspect the bigger ZT numbs the senses a little to how fast you are really going - it does it all without drama - although the Moto-build back-box has brought a rather refined growl to the party now! :cool:


Tricky, re the incline, that doesn't sound right, but going up the M62 from Manchester on the 4 lane uphill stretch, mine pulls like a steam train, although I do sometimes use 4th - but I am not about to admit to what speed that can reach. The ZT-T is heavier though, and a few years bac at one of the BTCC events at Donington, I was part of a 40 car parade lap, and got the chance to try out alongside a ZT-T 190, and I have to say the weight penalty of the ZT-T meant it was very close.

[Simon]

I also sometimes feel the car not pulling as it should in higher gears, even when travelling at speed.

I've got a nice piece of road just outside of my local town that is great stretch of dual-cariage way but this one hill seems to slow the car down. Maybe after tomorrows air intake cleaning and modding I'll take her for a blast along that same road stretch to see how it feels. I'll let everyone know my results.

[David3807]

I agree and had thought of this, thanks to Martinw as well

The other thing I forgot to mention, and dont know if this is common in the 160's or not - 80 mph, motorway, incline, foot flat to the floor in 5th and still losing speed!

Not just to the 160. Mines a R75 2.5 Auto so not strictly comparable but at 75/80 MPH mines only just approaching 3000RPM. I think the VIS valves start operating around 3200rpm when you can normally feel a surge of power. On a motorway incline mine will usually hold speed at 75/80 but any more than a gentle pressure on the gas will cause the auto box to go to 4 from 5. I think that the acceleration with even a 2.5 in 5th gear could be desribed as a little leisurely !!

On the assumption that an auto box mimics a manual box without the driver effort and given the slightly less power of the 160 the behaviour of yours would not suprise me.

I have also found on 2 KV6 cars that I have driven over extended periods that a better grade fuel such as V Power and BP Ultimate seem to make a difference in the responsiveness of these motors.

HTH

David

[MartinW]

Tricky, something that struck me last night was that like you, my car is well over 70k now (85k in fact) but at the last service at the MGOC w/shops, it occurred to me teh plugs had not been changed. I got them to fit new sparking plugs (£75 for the platinum type as used in the 1.8 VVC TF) and taht restored a bit of power! With modern engines it's easy to forget this essential part, but the rub is - the labour involved in changing the 3 plugs at the back is high! Access is difficult!

[Tricky160]

Tricky, something that struck me last night was that like you, my car is well over 70k now (85k in fact) but at the last service at the MGOC w/shops, it occurred to me teh plugs had not been changed. I got them to fit new sparking plugs (£75 for the platinum type as used in the 1.8 VVC TF) and taht restored a bit of power! With modern engines it's easy to forget this essential part, but the rub is - the labour involved in changing the 3 plugs at the back is high! Access is difficult!

I'll give it a try on the next service. Since my last post, I am a bit happier any way, I thinks its just me being fussy because of what I used to drive, if i 'drive it' it is fine, I just didnt expect to have to push the revs so hard (use lower gears) quite as much to get the response

[GreyGhost]

I'll give it a try on the next service. Since my last post, I am a bit happier any way, I thinks its just me being fussy because of what I used to drive, if i 'drive it' it is fine, I just didnt expect to have to push the revs so hard (use lower gears) quite as much to get the response

I trust you have had a read of this excellent how to:-
http://www.the75andztclub.co.uk/forum/showthread.php?t=152

[Countach]

Well, yes. an M3 is a fair bit quicker than a ZT160. ;)
I'd like to think the ZT/75 is more of 'gentlemans' car. It doesn't have to be the fastest out there because you know that driving it is the best driving exerience out there.

thats as maybe, but the lesser BMW's can be MuGged.. a local 330 is still licking its wounds after an encounter at the local Traffic lights (Yes I know, it was irresponsible, but it was a BMW,and they'd just done the dirty on MGR)