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MG MGF Technical - Throttle bodies on a VVC

Hi, i'm currently trying to fit a set of throttle bodies to my 97 VVC, o.k i know what your going to say, it cant be done, well i have changed the inlet cam to a standard type and pretty much disabled the VVC completely, i am also going to fit a k400 ecu, the throttle bodies and ecu are from Lumenition, can anybody give me any tips before i start pulling things apart.

Thanks

Martin
Martin

Will the ECU run the VVC mechanism? If it will then TTBOMK this will be a first.

Would be VERY interested in how you get on as this is pioneering stuff AFAIK.

Good Luck.

SF
Scarlet Fever

Hi Martin,

just to clear up the confusion, have you removed (or are going to remove) the VVC mechanism?

The VVC head is a good design, with much in common with the VHPD head that you see found fitted to 190 bhp MGF Cup cars and high performance Elise derivatives. A good starting point. The next stage is to junk the VVC inlet cams in favour of a set of 'solid' Piper cams - they sell a set specifically for the purpose, complete with parts required for the conversion. This is certainly the recommended route.

Regarding the Lumenition kit - have you bought it yet? No problems if you have, but if you haven't then I'd recommend you drop Dave Andrews and Dave Walker a line. They do some excellent tuning kits - including Jenvey direct to head multiple throttle bodies and the ever popular Emerald M3D ECU. I have no connect with either company, nor do I have personal experience with their products, but there are plenty of folks out there with this kit - and the maps are free - and readily available: options that you may find more tricky with the Luminition kit, although I see no reason why you wouldn't achieve good results with it.

Look forward to hearing how you get on with your project! :o)
Rob Bell

Thanks guys, i have already got the Lumenition stuff, i will be putting piper cams in along with vernia gear, and i thought with the VVC head having larger ports and bigger valves i am hoping to reach 200 bhp i have had a little experience with the emerald ecu but the first time i fitted one along with a supercharger kit it was faulty and cost us nearly a day to sort it out, the reason we went with lumenition is that the technical guy there Paulo, was really good but he has left the company now, i will keep you all up to date with developments
Martin

OK, i'm a lot clearer now - cheers for the explanation.

:-)

SF
Scarlet Fever

Okay, I understand now - and yes, I agree with you - the VVC head is a superb place to start. i don't think you'll see 200 bhp without some judicious porting of the head, but 170-180 should be readily achievable with the hardware you've got.

Do Luminition supply the Maps fand mapping software/ hardware or free, or is this extra?

The car is going to be great fun - are you planning on taking it onto the track? The MGs on Track group are currently putting together the 2004 calander - and some events are already available for booking :o)
Rob Bell

Thanks Rob, i have had the head skimmed ported and polished to a knifes edge and i am also thinking of shortened con rods and forged pistons, the only thing is im a bit wary of losing the mid range torque by getting rid of the VVC, im alo not completely sure of what i need to take of to disable the vvc obviously the cams will be changed, if you have any input i would appreciate it i do have the maps from Lumenition and there is a Lumenition agent not far from me so as long as i can get the car running i will shoot down to him and he will set it all up and dyno test it, i was almost going to turbo technics for a blow job but i dont think it will be as reliable a doing it this way.
martin

Being that close to Luminition should be a real advantage martin :o) Should be plenty of good advice on tap.

If you've got the Piper inlet and exhaust cams, then you've already removed the whole VVC mechanism - so that's no longer a problem. :o)

Who's done your porting?

Ah - you've brought up the forced induction versus naturally aspirated tuning debate. Suffice to say the two result in very different power delivery thanks to completely different torque curves. Superchargers may be more expensive, but they give instaneous torque from right at the bottom of the rev-range. Normally aspirated engines tend to need much more engine speed to develop their power. Result - in the "real world" forced induction engined cars are frequently faster than their equivalent capacity normally aspirated brethern.

Of course, there is no reason why you couldn't supercharge your ported VVC head equipped engine at a later date, although the cams and inlet manifold would need to changed to suit the new application.

Out of curiousity, what engine speeds are you going to be looking at for your engine? Forged pistons and different con rods may be worth considering, but the crank shaft may need attention. If you are really going to the expense of building the whole engine from scratch, then you ought to consider getting the whole engine balanced (pretty cheap, once all the parts are stripped down) - and consider a strengthened brank bearing ladder to stiffen the engine so you can break the 8000rpm barrier.

Are you planning to use the standard gearbox? Another thing worth considering is a close ratio (CR) gearbox. This will enable you to make full use of your powerband and higher rev limit. :o)
Rob Bell

Hi Rob, the more i think about what sort of power delivery im after the more im now leaning towards a blower, i have a pg1 gearbox from powertrain with a lightened and balanced flywheel, i think even with all this work i will be unimpressed by the mid range torque and as you quite rightly say forced induction cars seem to be faster, im in a right situation here, throttle bodies v blower
Turbo technics use the emerald ecu but do not give any equipment or info regarding re-programing it, i have spoken to a number of elise owners who are impressed y the blower but not so in the reliability.
Either way the engine will be superb and all balanced as you say.
martin

I thought that TT use an interceptor chip and an additional fuel injector for their kit? It's not an Emerald as far as I know. Regarding their reliability - hmm. I've met a couple of folks with these in their F's, and I think it is fair to say that each have had some teething problems with their installation. It is also fair to say that TT have helped them through, and all seem happy with their choices (but none are exactly high-mileage motors). There seems to be more experience amongst Elise owners - there is even an email list (Yahoo I think) - might be worth getting some advice from these guys. They lurk on the Elise BBS and the SELOC forums as well.

If you've already got the Luminition kit, you might as well press on with that project, and see how you go. Should be a steep learning curve - but you shouldn't be disappointed :o) Hopefully with the throttle body set up, the mid-range torque will not suffer in comparison to standard, and indeed the top end will be much much better...
Rob Bell

Rob, im sure that TT are using the emerald ecu and they dont have a 5th injector, i have just spoken to Rob at TT and he says there are always a few teething problem, i suppose this is ecpected when supercharging, the more i think about it the more im leaning over to supercharging, the only problem is if i do have some teething problems im a bit far away just to nip to Northampton, TT use a 13 row oil cooler kit along with a small intercooler after the blower but obviously before the ne inlet manifold, they use the standard 42mm TB with the standard fuel rail and airbox, looking at the set up with a few minor mods to there 230 spec i think i may well achieve around 240bhp
Martin

Maybe TT have evolved their kit since I last looked at it- the original had additional fuel injectors in their own-designed inlet plenum, with a Superchips-derived interceptor chip piggy-backing the original MEMS ecu (so it retained all the alarm and diagnostic functions of the factory car). Perhaps they've now gone fully with Dave Walker's Emerald?

Here's what their website says: "Fuel system: Standard Unleaded 95 RON fuel. The standard injection system is retained but supplemented by twin injectors. Fuel and ignition controlled by digitally mapped ECU. "

The TT supercharger is now quite a well developed kit - as you say, it comes complete with charge cooler and oil cooler, although the engine itself is left pretty much alone (surprising this, when you look at the extensive work that Brodie Brittain Racing do to their turbo-charged K-series engines - see http://www.bbrgti.demon.co.uk/ )

I have to say that if you want a seriously faster car, then it is torque that you need. This is an opinion that I share, having given the topic some thought. And perhaps, if you don't necessarily want to go down the turbo/supercharger route, then there ain't no substitute for cubes: the Ford Duratec 2.2 litre will fit in an F, is only fractionally heavier, and I am told, will bolt straight onto the PG1 gearbox... In fact, it may be possible to drop VW's VR6 lump in their too, but that is probably significantly heavier than the K-series, and will upset the F's handling.

So if you weren't already faced with too many options, here's another, just to make things more complicated ;o)
Rob Bell

MMMM i have recently spoken to Chris at raceline and he is developing the ford duratec 2.3 from the states, he said this will go straight in and i can also put throttle bodies on it, he has done this to an elise and had figures as high as 300bhp WOW well worth a look into the only thing is im so off the idea of throttle bodies on the K that im sat with useless throttle body kit and ecu, maybe the whole duratec thing is a bit wild and as you say the handling maybe compromised although i have got lowering knuckles, 4 x spax adjustables and poly bush kit on the car and i am also running on 16 in rims, the vw v6 engine is very heavy so i think i can rule that one out.
Which ever way i go i need MORE POWER.
martin

It's the Raceline kit that I had in mind when I mentioned the Ford Duratec ;o) Might be worth waiting to hear how Raceline get on with this development - and wait to hear what the costs involved are: engine transplants often turn out to be considerably more expensive than you might first think! :o/

I haven't asked, but what is your budget, and what are your torque and power targets? (200bhp power I see - but what torque?)
Rob Bell

At a minimum i was hoping for 200bhp with approx 180 - 185 lb torque, im not really running to any budget at the moment but as you say an engine swap will be expensive, but you know what they say.
NO PAIN NO GAIN
I think i will scrap the throttle body job for the moment and sell them on, i think its really between the blower and the Duratec engine swap.

Martin

From my experiences with my engine (flowed hed 285h cams, emerald DTH TBs) i'd strongly advise using a CR gearbox, as the normal power/torqe curves are maintained throughout the rev range untill the normal engine tails off, this is where my modified engine keeps on pulling, as a result the engine needs to be revved to the red line to get the most from it.

A larger engine may be a better "money no object" root to take, and would certainly be my preferred choice.
"There's no replacement for displacement!"

Also the audi tt engine fits in the F/Elise i belive.
Kingsley

180-185 lb.ft from a 200 bhp engine shouldn't be all that hard to achieve from a properly ported VVC head, cams, exhaust manifold, exhaust and MDTH TBs - but that peak would be close to 5000rpm. As Kingsley says (he has a DVA ported head, Piper cams, multiple direct to head throttle bodies etc) - it's got standard torque up to that point, and there after it screams to the red line.

So the question boils down to where you want that torque - and from what you are saying, it sounds as though you want a decent wedge of it from around 2000 rpm. You'll need extra displacement or forced induction to achieve this.

MG World carried an article on the Brodie Brittain Turbo conversion on an F - again not cheap, but these kits do seem to be thoroughly engineered.
Rob Bell

Dont forget with an engine swap you may be able to maintain normal sound levels, with most modifications to the existing engine expect to wear earplugs for long journies, not for the engine, but for the girlfriend.
Kingsley

This thread was discussed between 16/11/2003 and 17/11/2003

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