Possible BHP for very very little money for MG/R KV6 owners... (your thoughts?)


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MG TF135
Me and a fellow MG ZS180 friend have been talking a lot lately about a possible mod for the 180 or 190 engines that could cost less than £80 in parts.

After much research, measuring and testing we have come to discover that there is the possibility of getting over 200bhp from a KV6 without a remap or spending loads of money.

There are some differences in the 180 and 190 engines that give them their different power. 2 of the biggest ones for the 190 engine is that the intake system is better for infinite better breathing and also the Inlet cam is advanced by 4 degrees using a static pully. We also discovered that the exhaust cams on both engines have a duration of 244 degrees and 8.8mm lift, instead of the 236 degrees and 8.2mm lift the standard inlet ones use.

So our theory is, why not use 2 pairs of exhaust cams giving them the mild fast road cam effect as well as the inlet pullies from the ZT190 giving you 4 degrees advanced timing. The Valve spring and cap ratings are exactly the same on the front and back which helps a lot.

So for the price of £70-80 you can have a mild fast road cam set-up at 244 degrees aswell as advanced timing on the inlet which would be the same effect as having vernier pullies. Much better than spending £500+ on Kent or Piper just for cams and no one seems to make the verniers anymore so this theory should be some proper bang for buck and is a perfect mod if belts are being done at the same time.

We predict (due to the 260 degree Piper Cam giving 20+bhp on a standard engine) That the cams alone will give in the region of 10+bhp (as they give roughly 50-55% increase of the Pipers) and then a further few bhp from the advance timing on the inlet. So in theory 15+bhp is not impossible at all. Matched with a full 2.5" straight through from flexi back, modified sealed air filter and a remap should see closer to 215-220bhp. And of course maybe another 10 if a walbro fuel pump and uprated injectors are installed before the remap.

So again, in theory, there isn't any reason this wont work aswell as a full cam and pully set up from a leading company, just a milder road use version and anyone who knows what a ZS180 is like, giving it 215-220bhp will put it in a different league.

What are your thoughts.
There's no reason it shouldn't work in theory. But Vauxhall guys have been doing it for years putting 2 pairs of 3.0ltr cams in the 2.5, the 2.6, 3.0 and 3.2. Works wonders. I just don't think hardly anyone in the MG world has realised what is available under their noses.
If I remember rightly, a few members who own the MG ZT KV6 have tried and failed. At one point I was even seriously looking at ZR's with HGF and ripping the engine out and putting in a KV6.

However, the KV6 is already at its peak power and any more then 260bhp on them they blow up. The only way to get decent power out of them is Supercharging but thats expensive. Camming option is a good one, but you'll be hard pressed to get any more then 200bhp even with a port and polish etc etc.
Many have proven that theory right about braking the 200 mark without major modding. Mine is already 201, but need a walbro fuel pump and a set of uprated injector before going down the remap route, but should be looking at 215-220bhp when done.

There is a lovely ZT190 on the forums who is running a proven 247bhp N?A and the stuff he's had done isn't actually out of the realms of costing a fortune.

But after much reading, no-one or hardly anyone has tried this method we are playing with. Another one aswell is to use the inlet manifold from a Rover 825 or 827 as they are full metal inlet aswell as the VIS system, and also uses a twin throttle body set-up. Just need a circuit to make the VIS system work to the MG ZS rev setup for it's standard VIS.
This is an awesome find. I think it will work very well and give quite a large gain for the money! Well spotted.
Many have looked at the ZT190 but found it to be alot of work for little gains. There has been many opinions on the actual differences on the 190 none actually proven accurate. I'll be interested to see what the actual gains are with those changes but doubt if you will see the figures mentioned. If proven right then it may be of interest assuming people keep them when the belt change is due again, enthusiasts will of course. At least with the 270 profile you can get the current cams reground for a fraction of the new cost but again with the lack of verniers there is no room for adjustments. Personally I am happy enough with what I have got and not bothered about chasing numbers and focus on the handling and braking where it is pretty decent base to start from.
I have the press release literature here if interested on the exact difference of the 190 engine to the 180 version ;)

Also, the figures I talk about are not impossible at all. I'm not thinking of doing the "190" conversion, but rather create an engine using the different engine parts. If already owning a 180 then all that is needed is another pair of exhaust cams, and the static pullies off the inlet of a 190, thus giving a 50% version of fast road cams and verniers (the statics have about 2 degrees adjustment if using the 190 timing kit as the 180 kit is different). Piper etc say that a 20+bhp gain can be seen on standard application and none of them sell the verniers for the KV6 anymore. The exhaust cam is just over 50% of the profile of the Pipers Fast Road Cam. So a 50% gain of the pipers for 15% of the money is definitely worth it.

1 of the main things they talk about making the difference with the 190 is the 4 degrees advance timing on the inlet, and the larger intake on the air filter piping (hense why such a noticeable gain can be felt on the ZS180 when fitting after market air filter's etc).

So if the list consists of:-

- 2 pairs of exhaust cams at 244degrees a 8.8mm lift (instead of the inlets which are 236 and 8.2mm lift)
- 190 Inlet cam pullies for the 4 degrees advanced timing.
- Full 2.5 inch straight through exhaust system.
- Aftermarket breathing mods (filter etc)
-Walbro fuel pump.
-Uprated injectors.
-Rover 827 or 825 metal inlet manifold and twin throttle body set-up.

All will definitely get you near the 215-220bhp area with further internal porting still available if required. (this is what makes said 247bhp ZT190 so much more powerful.
Could very well be. My engine is having a little rebuild in the next 2-4 weeks so could be an opportunity. But will be going to buy a spare engine aswell which can be built up over time. Also using the 190 for the already port matched heads and the exhaust manifolds. Found out aswell that a stand alone system will work for the VIS system from the Rover 825 and 827's better than a circuit board being made which will also open a lot of doors for further tuning and probably better tuning of the bits I'm going to use. But in doing so will then take the costs of this theory rocketing. The whole idea of this theory is that the parts for it wont cost any more than £100, so in theory from a standard ZS18o with the 177bhp, should see an increase of over 30bhp which isn't bad for total cost of £350 inc remap.
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Hmm... Worth a shot isnt it!

I remember the Scotch Lock King did one of the first ever throttle body conversion on the KV6 and only managed 230bhp from it! The aim was 250bhp!!
You get over 240bhp without going near throttle bodies, super charger or NOS. Been done a couple of times and as mentioned, the ZT that's floating about is stunning. But unfortunately, getting anything out of N/A car is hard and costly, but covering the basics is a good start and aslong it gets near or over 215 then I think it's work it for the money spent.
Vauxhall engines are far easier to get a bit more out of, just by using 2 pairs of 3.0 cams will knock a 2.5 up to 200bhp alone. But it's all about breathing with V6's engines. And aslong as the engine can take the extra heat, then the sky is the limit, well your pocket is anyway lol.
I have the press release literature here if interested on the exact difference of the 190 engine to the 180 version ;)

This by any chance?

The ZT range has newly-enhanced versions of MG Rover's all-alloy quad-cam V6 engine. For the ZT 190 models, several special features have been engineered to achieve the higher power output of 190Ps or 140kW, and increased torque of 245Nm.
Beginning with the variable length induction system, the air intakes have a 15% larger duct and a new intake diffuser. This provides a smoother airflow with less than half the usual pressure drop; it has also been tuned for a more sporting induction sound. Internally, there is a new inlet valve cam profile, advancing the inlet valve opening by 4°, as well as improved inlet porting.
To withstand higher cylinder pressures, the gudgeon pins and big end bearings have been upgraded, and the oil specification has been raised to ACEA-A3 for protection at sustained high revs.
A further contribution to performance comes from a new exhaust system, with 60mm diameter pipes in place of 57mm, new low-restriction metal-based starter and main catalysts and a modified rear silencer unit. This has larger-bore internal pipes, twin straight tail pipes and a mechanical valve that responds to exhaust pressure at around 4500rpm to by-pass the internal baffles.
This reduced back pressure helps create an attractive sporting note while still meeting all legal requirements for drive-by noise.
A redesign of the engine ECU software and specially designed MG throttle cams provide the right sporting feeling of responsiveness to the accelerator pedal, with a deliberate reduction of the normal throttle on/off damping.
Finally, an enhanced cooling system, with 20% greater cooling intake area, uses an improved-flow radiator and top hose configurations, with a new plate-type oil/water oil cooler replacing the oil/air heat exchanger.
Hmm... Worth a shot isnt it!

I remember the Scotch Lock King did one of the first ever throttle body conversion on the KV6 and only managed 230bhp from it! The aim was 250bhp!!

That car was broken up, shame as Steve spent a lot of money over a few years! The plenum was off the BTCC racecar, took some work to get it running and wasn't finished tbh, hardly surprising I guess considering. There were high hopes for that but it cost too much for all the add-ons.
The one I'm on about is still running bud. Its a black one with full red Alcantara interior, he also owns a blue 190. I know the one your referring to though, bloody nice motor.

But yeh that's the info mate ^^^ ;)
Get a ZT260, supercharge it, job done :)

Ok less of the sarcasm....
I'd say just give it a go... and see if it actually makes a difference, theory sounds good but in practice is where the true test is
Not doing this now buddy. The whole thing leading me to try it was the fact I need to have my belts done soon and seemed a logical thing to have a go with while it was apart. But going down the T16 route now buddy. Check out my "Oh god I've gone and done it" thread ;)
Hi there was reading this article and you mentioned about fuel injector upgrade and pump but there is no mention of what or where you can get these could you advice on these please as I'm working on my 190 and very interested in this so far I have had a s/s exhaust full de-cat 2.5" straight through with a performance back box. Remap done by Andy Reid , closed air induction, mods I'm looking at are inlet manifold and throttle body from the 825/827 where can I get my hands on one of these. The fuel injectors is the main problem. Any help would be great many thanks
Hi all...I see this is an old thread but wondered if anything came of your investigations. Currently have a zs180 and a set of 190 cams going spare...sounds a very interesting mod for someone. Any more info much appreciated. Many thanks.
Greetings HeyL33 and welcome to our TorqueCars forum :)
Might I suggest a chat with our esteemed expert @stamford on this subject. He should be able to point you in the direction that you seek. Good luck

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