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MG MGF Technical - VVC 160 on steroids.

(Trophy 160)

First, I would like to clarify the following points :

- The rolling road was the same one.
- The conditions apart from temperature and air
pressure were exactly the same.
- The same RR driver.
- The same gear changes.
- The same air filter.
- The same air pressure in the tyres.
- Everything else I missed was the same as before the test.
- The same RR is used by CARLSSON [2] to fine tune their cars (Mercedes Benz tuner)

The result (and RR graphs) prior to the modification can be seen on ROB Bells site [1]

The results prior to the engine mods were :
St. Filter : 153 bhp@7060 rpm and 128 lb.ft @ 4750 rpm
Greentwister: 162 bhp@6680 rpm and 137 lb.ft @ 4700 rpm

Now to the modifications :
- Dave Andrews Full Ported VVC head.
- Hotter VVC exhaust cam by piper cam for Dave.
- AMT Exhaust manifold.
- AMT Exhaust.
- Intake plenum matched to the head by AMT.
- AMT Oil/Water heat exchanger (listed to be complete)

The Result was :

192bhp @ 7090 rpm and 145lb.ft @ 6680rpm
OR
195ps @ 7090 rpm and 193nm @ 6680rpm

My reaction frankly, was that I couldn't believe it. We made 4 consequent runs (to setup FSE) and all resulted in above 140kw. I was baffled as these modifications were predicted to release like 182PS and not 195PS, however there is nothing I can do about it. I drove the car (before the RR) to the rev limiter in 5th gear on the Autobahn, reaching (a bit) over 240 kmh, and the car still had enough torque to go further. The same was prooved by the RR session, it would have pushed further if it would haven been allowed to (gear, rev limiter).

Now where's the beef ?! Unfortunately I have no access to a scanner at the moment, so I made a picture of the screen output of the machine which can be found here [3] further details will be posted once available.

[1] http://www.mgf.ultimatemg.com/fuel_rail/FSE_fuel_regulator.htm
[2]
http://www.carlsson.de/
[3]
http://www.sniff-em.com/rr1.jpg
Thierry

Thiery,

Impressive figures! :-)

Only got one question for you, "When were the runs made?"

I assume the 153bhp and 162bhp runs were on the same day, but fitting all the other modifications takes time - i therefore assume there was a gap between these runs and the 192bhp run - probably more than a week or two?

This could explain the unexpected gains somewhat (but probably not all of them).

Basically there are too many variables to be able to cross compare power runs done on seperate days.

I'll explain.

What you have are 2 'snapshots' of not only the performance of the car, but also the calibration of the rolling road, the atmospheric pressure, the ambient temperature, the competence of the driver, the competence of the rolling road operator and a myriad of other little things!

So unless the runs are done back-to-back you can't really compare them directly, all you can do is say "This is what my car produced on this day, on these rollers"

I mean, taking an extreme example, what if, say the driver on the 153bhp run had had been out drinking the night before and had a hangover! This would affect the power run!!!!! I know i'm being silly, but all these things make a difference.

When we do power runs we try to do them back-to-back - it's the only way to make them comparable (and even then thier value is somewhat debateable).

So, where does this leave you? It leaves you with a power graph for your car which is excellent and one that proves a substantial increase in power after the modifications.

The actual increase is impossible to quantify precisely if the before and after runs were not done on the same day, but the difference is large enough to say that the modifications were very definitely a big success.

Top job. :-)

SF
Scarlet Fever

Your statements are obviously correct and apply to life itself, the moment I write here is only the moment I write here (cogito ergo sum) and does not quantify for the past nor the future. Well were being philospohical here aren't we.

The facts are that the RR wasn't touched and wasn't "recalibrated" nor was the driver drunk. *bg*

The 153 and the 162 were run with a gap of two days and a difference of 2C and 0hpa. That was months ago, heck I am not trying to compare them. 195PS is 195PS on an RR which prooved to be accurate (That's why I provided the previous data, to show that the trophy didn't score 175bhp before..). The point is I am more then satisfied and somehow leveraged what has been said to be possible with the VVC mechanism (afaik).

Thierry
T

Thierry,

Those are some pretty inpressive figures, have you emailed Dave A with the good news?

Maybe what we should do in the future is a trans european rolling road day :o)

Tim
Tim

That would be a great idea Tim, I actually wanted to come over visit some of you anyways. Would be great to see each other.

I did not mail or phone Dave, frankly he won't believe me anyways. He reads here, he'll find out eventually.
T

DVA always 'under estimates' his head conversions Thierry - as Tim found when his 155 'K13' kit gave up to 10bhp more than that!!! Similarly, Dave's VVC has similarly over performed (175 with a modest porting and a standard exhaust cam) :o)

But 192bhp? Wow, now that is impressive!

Obviously, there are problems comparing one RR recorded on one day with another on another, but if the compensations for ambient temperature and barometric pressure are performed properly, the results can be very reproducible - as we've seen at Dave Walkers' and the G-Force rolling road.

Andy, I don't think we can attribute the +30bhp gain that Thierry has seen to differences to this, but it is a good point well made.

The absolute RR figure can be misleading, as calibration is critical (the G-force estimation of flywheel power is way out for the MGF - but the figures at the wheels are pretty much spot on - to within 0.1%). What is encouraging about the RR that Thierry has used in the past is that the base line figures for his previously more or less unmodified Trophy is pretty much on the ball for what you'd expect from this engine.

Assuming that the calibration is on the ball, and there isn't an 'optimistic drift' at higher power levels, then I think that we'll have to accept that Thierry's engine, on MEMS, is making astonishingly good figures.

Thierry, you've got MEMS3 haven't you? How's the fueling? Any indications of the engine running lean before re-setting your FSE regulator? And how is the fuelling now: is the stoichiometry stable throughout the rev-range?

I wonder whether one of the aftermarket chip tuners can reprogram your MEMS for you to better suit the engine now its been modified?
Rob Bell

200 bhp us THE magic number!

When I was blathering on in my MG World column I used to say that 200bhp was a suitable target for our cars

looks like somebody has done it..just about

car must really go!

Red lining in top!
now we are talking!

time for you to consider gears!!!

Neil

Theirry

I think you have probably done as much as you should want to to the engine.
let it settle down and see if it is durable.

Get some serious miles under it this summer!

If the Darkside has utterly taken over ( which it looks like it has!) experiment with brakes and suspension to cope with all that power!

Great performance though
DVA will be chuffed as you should be!
Neil

I'd be well pissed off I missed 200BHP if I were you ;-)

Good show
Will Munns

Now with an increase in power like that

what could be done to my 214?

Neil

Nah, don't be silly, you want to stick 200 horses in a metro, that'd really piss off the boxters!!
Will Munns

AFAIC 180bhp is the magic number, this is 100bhp per litre and is the threshold most tuners aim for.

I'm hoping to get there, or close to it with the NOS, more on this as and when...

SF
Scarlet Fever

180 bhp nice
DVA head, cams etc should get you most of the way there without the NOS factor!

wonde what
Neil

I still have MEMS3 yes, the fueling was way off, I had to give it 2500rpm in first gear to start or else the engine died. Now the starting procedure is normal again, we explicitely gave it a bit more fuel in exchange (lost) with 3 PS, to make sure it does not run too lean.

No wide-spectrum lambda sensor unfortunately.

Next month AMT will change the fueling time and other magical stuff with the original mems3 unit. Let's see if we can squeeze another few PS out of the unit. Maybe by changing to the AMT airbox and togehter with MEMS3 tuning I might reach the magical 200bhp.

Let's see how long the clutch and the gears are going to last on this one.

For the other items, I have techspeed bilsteins and techspeed type lowering (cutting hydragas units), aswell as the AP calipers, which really help at speeds above 200kmh.
T

Good luck with the AMT tuning Thierry :o)

Pitty the broad band lambda sensor was off line this last time :o/

Regarding clutch and gearbox - it's torque you have to worry about, not power. With 'only' 145 lb.ft torque, you have nothing to worry about ;o) PG1 comes rated up to 240 Nm (although the MGF may come with a slightly lower rated version - but there is a big 'comfort margin' built in :o) )
Rob Bell

Does the trophy 160 have a stronger bottom end that the std 1.8i or VVC?

I ask because everything I have read warns about running the "normal" engine about about 160-180 bhp because the bottom end will give out unless it is beefed up.

I would be very happy is I could get my 1.8i to about 160-180 bph with out breaking the bank, its currently about 146-150 :-)
Steve Ratledge

When MG did the black F based EXE 151 (?) bonneville speed record a few years back.

they walloped a smaller capacity k series up to 400 bhp through turbocharging to deliver the power/speed necessary

I know for a fact they did not touch the bottom end I heard it from their own mouths!

"As strong as the Eiffel tower" it was quoted
Neil

But the 1.4 turbo K that Janspeed prepared for Rover only had to cover a few tens of miles, not several hundred thousand miles! ;o)

It was indeed a mighty engine and a terrific achievement for both MG and Janspeed. I had realised that Roy @ Techspeed was closely involved in that particular project! :o)
Rob Bell

>>But the 1.4 turbo K that Janspeed prepared for Rover only had to cover a few tens of miles<<

But it must have been fun at the filling station ...
"I'll have 50 litres of Optmax and 25Kg ice for the intercooler please"
OK, I promise not to mention hayabusa engines.

ps. Brilliant result Thierry - any thoughts on raising your rev limit (say to 7600?)
Steve

This thread was discussed between 20/03/2004 and 23/03/2004

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