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More power, Motec, Money and Misery

T1RBO

New Member
So,are you reading this to hear of the misery part?

Well with all the 'why only 230bhp' threads and everyone screaming for 350bhp, I thought that I'd put in my two-penneth to try and save someone the misery - I've not had anything I wasn't expecting on the money front!

This is all my take and am happy to be corrected - you can reply with how you plan to extract 600bhp and blow all of us away - it's just what I've worked out with the development of the rally car over the last three years.

So, firstly, why is the standard car only 230/255bhp - and often short of that? IMHO, the potential for warranty claims means that manufacturers always err on the cautious side. Renault are not a specialist manufacturer and customers have a habit of using and abusing cars for 100,000 miles or more with minimal maintainance. Said customers also get pissed when their car is landed at the side of the road with engine or transmission failure. Consequently, while Renault engineers clearly had the knowledge of how to make the engine make more power, the bean counters put the brake on turning out 100bhp per litre.

I think in essence the reason for the safety net was to protect the transmission which has proved to be the weakest link. The car has massive traction and knowing how unsympathetic clumsy drivers can be, meant that the last thing the warranty dept needed was clutches, shafts and diffs exploding under 300bhp launches.

To cope with more power and give a safety margin, components would need to be uprated and that's an expense that you can't recoup on a niche product like the vee. By way of explaining, compare the rear hub from the Trophy with the one on your roadgoing car....

hub.jpg


So, you've bought your 230/255 and understand that you might need to replace bits more often, and you promise to be kind to the transmission. Now you decide to spend your pocket money on upping the power to the 300+bhp that Mr Regie always should have given us.

The initial stages are simple and cheap - first, get the engine in perfect shape with one of Scotty's services! Second, fit a better air filter and a freeflow exhaust - NOT the same as a noisy one! Finally, a 'chip' by any of the firms on this forum.

Realistically, I think this is as far as you can go with off-the-shelf stuff.

Beyond this, tuning naturally aspirated engines is horribly expensive but the V6 is more so, as any of the methods WILL breach the transmission. [smilie=icon_eek.gif]

The big bottleneck with the vee initially is air intake as the single plenum strangles the car. The single throttle body only flows so much air so resolution is either the twin-plenum Trophy setup or multiple throttle bodies on a custom manifold. Around 300 bhp, the Trophy injectors are wide open at full throttle so, t/b's are the only answer much past that.

Past 300bhp, air starts to become a problem, and not just what the engine can draw. The lack of breathing space around the engine bay both limits and disrupts the amount of air that can be sucked in. More so if you intend to leave the standard engine covers on.

Another problem is heat management - we have a bulkhead so no covers, holes in the rear window, side window vents, fans in the air ducts and still can't lose the heat. Engines don't like that sort of environment and it's unlikely that we crawl through traffic like a road car.

Similarly, going bigger capacity is, by all accounts, likely to run you into overheating problems, particularly as you near 3.5-litre, when the water jacket is dangerously thin.

And so to engine management - again, not quite as straight forward as bolting on either. As well as the engineering and cost involved, the management of this much fuel and air not something that a 'remap' of the Renault ECU could take advantage of. Not in a million years...

Enter Motec - or some of the other serious competition. The first myth to explode is that fitting Motec is something that you can just throw at the car - it can allow you to make the best of an engine, but it also can lose you heaps of power or, in my case, cause other management related problems. Fitting Motec is only part of a large commitment to testing, adjusting, checking and more testing. We have had three separate sets of specialists working on the car, all have made improvements but none have so far got it perfect.

Secondly, I don't believe that there is a wealth of knowledge about the V6 that can be transferred to someone going the Motec route. A Group N Evo or Subaru maybe, but all the big power V6 cars have quite different specifications - mine, Mike's Turbo, Tim's NOS car and Mike Sellars' old car on multi throttle bodies with cable rather than fly-by-wire throttle. This means MoTeC is an individual route, not a bolt on. There may be baselines to work from, but no one has a map for your car, it needs to be developed.

If you asked me now, I'd say the simplest way for bigger power would be to go for a Trophy engine along with the Magnetti Marelli ECU. The standard transmission might just live with the 275bhp that you'll get reliably - our engines have been 100%, quite astonishing really.

If you simply have to get 300bhp or more, we are realistically talking of spending £20K+ once you can make it all live together. Surely not I hear you cry. Ask any of the serious car owners and they'll confess! Much more expensive than when we 'talked up the spec'!

If you can find one, you'll need the Sadev sequential 'box, shafts, hubs etc from the Trophy. An engine with the management system and on top of that, budget for at least £5K to get MoTeC or similar bought, fitted, mapped and debugged.

So, good luck with all that, the one thing with these cars is that they do bring out the madness in all of us.....
 
Interesting and enlightening!

Questions of course...... :)

Heat management -

Did I once read of a v6 possibly Mike's which had heat extraction fans?
Is it Tim whos vee looks like a collander and is this still not enough to loose the heat?
Does the standard car (with covers on) need more in the way of engine bay cooling?
 
The collander makes quite a difference, the key is getting the air flowing through and out again.
The extraction fan at the rear is for traffic jams and is a side pod fan in reverse.
I've got a roof vent over the engine bay, window pods, collander tailgate and extraction fan and possibly something else to try too.......Quite extreme but as Mark says there are issues with heat back there.

DSC00152Small.jpg


For a standard road going V6 the issues are not serious but if you start thrashing it all the time or do a lot of track days stuff can start to melt....
Yes, I'm mad!
 
I think the post is excellent and makes a lot of good points. Manufacturers do indeed attempt to make reliable and long lasting vehicles within safety, reliability and cost parameters. Engines are often de-tuned from their potential to reduce the need for improved parts in other areas i.e. gearbox and transmission, brakes etc. So to tap into this potential requires the investment the manufacturers haven't put into the mainstream models. The Vee is no different, however Renault do seem to put themeselves out there more than most manufacturers and it is a very good all-round car - as we mostly appreciate.

My view is ... it's a lot easier, cheaper and rewarding in many ways to tune a car that is more robust and mainstream than a Vee and perhaps a cheaper base car ... I for one have no interest in making my Vee go faster or handle better - it serves it's purpose for me and ticks all the boxes as it is. If I had a specific use in mind for the Vee, other than simply a second car, then my outlook may also be different.

I do always read with interest and respect those who do tune their Vee to extremes for what often seem to be specific purposes or areas of interest.

Martin
 
k1ano":2i99oh1a said:
I do always read with interest and respect those who do tune their Vee to extremes for what often seem to be specific purposes or areas of interest.

Martin

Took the words right out of my mouth there Martin.
 
First off, what a cracking write up! Many good points made. The heat one is my favorite!!! Especially after my incedent at rockingham lmao. However, I do have some questions.

Why is everything assosiated with the vee so much more expensive when in reality the engine itself isn't too special? On the gearbox side of things for instance, why is the next step from an o/e gearbox a SEDEV sequential box? Why has nobody considered adapting a cheap, readily available, easy to find and much stronger box to fit? I know of a really common 6 speed, cable operated tranverse box' that can take 500bhp allday long. To have a bell housing made, driveshafts shortened/remade wouldn't cost more than a couple of £k at the most. No doubt the SEDEV is the dogs nuts when it come's to things but surely it's not the only solution.

I'm really not pointing fault at the right up as its clear you know your stuff but i am one that wants to make my vee go much quicker and am just curiouse why "bang for buck" seems to go out the window with our wicked little cars.
 
Great write up.. and very interesting comments made..

I saw both Mike's and Tim's cars at Scotts.. both very impresive bits of kit, and way over my head the amount of work thats gone into them.
As mentioned by T1RBO, its becoming increasingly clear to me, that anything more than some form of induction kit, replacement exhaust and manifolds, followed by a remap and it's into serious "here's my wallet, help yaself" territory.

Love reading these type of threads.. just wish I had the funds and know how to do something similar.
 
Oldskoolbaby":3eur4xtv said:
why is the next step from an o/e gearbox a SEDEV sequential box? Why has nobody considered adapting a cheap, readily available, easy to find and much stronger box to fit?

Could be and should be done.........just needs a volunteer
 
The way I look at it, if you love driving your vee then dont mod it! All the modded cars here spend very little time being driven! I remember Mike's car in its ealier modded state at a few events and TRW1 turned up at WSR a few years ago, I know the other is a rally special so dont expect to see that in Tesco's car park. Great cars guys and I admire your ability and just how much you have put into them but just how many miles have they done in the past couple of years?
 
eastlmark":3n6ntg57 said:
The way I look at it, if you love driving your vee then dont mod it! All the modded cars here spend very little time being driven! I remember Mike's car in its ealier modded state at a few events and TRW1 turned up at WSR a few years ago, I know the other is a rally special so dont expect to see that in Tesco's car park. Great cars guys and I admire your ability and just how much you have put into them but just how many miles have they done in the past couple of years?

Good point - from my point of view I've literally not driven the vee for 3 years and 5 months...

There's a limited supply of "professionals" out there, they all seem to work in an alternate reality where timescales are plucked from thin air and budgets are elastic.
 
You're right of course Mark.
0 miles, last 2 and half years.
It's a sacrifice worth making for me to get the car I want built to order. Frustrating though of course!
Hope to see you all at Tescos next year....
 
350 t0 400 bhp is my target money is an issue just like every one else and for the bit that dont work on the car like shafts gear box clutch etc if there shit then i will have them made if no one else has already done it if your going for it you might as awell do it wright in the first place any one got any tasty bits that i might be intrested in let me know going to stroke engine balance head work and possible super charge always been my aim to mod the car and try to keep it looking standard sleeper style rerly should leave it buy a spyder and tweek that would be cheaper
 
Really, the point of the post was a heads-up for those contemplating modding their cars, rather than those who think 'standard is best'.

I absolutely agree with the 'leave well alone' if you want a road car with more character than many cars costing ten times the price.

I also take the point of loony timescales and mad budgets - I've suffered from both, but in this regard, neither are Clio V6 specific. I've had the same experiences with Mini's, Escorts, Evo's and pretty much everything else I've competed in. Maybe it is a genuine love of 'engineering', maybe it is a misguided sense of thinking that I can do a better job than anyone else - either way, seriously modifying a car is expensive and always takes an age. More so when you use the services of the 'gnomes' who always seem to work from sheds, think 'next week' is December, but think nothing of taking three days to fettle something to perfection. Commerciality is not part of the equation and most of the proper motorsport guys work this way. Their stuff wins, Halfrauds stuff falls off, your choice.

I started the thread as an attempt to prevent disappointment for either those who are new to the car or, wanting a bit more, are thinking of lashing out on mods that will swallow cash, but have little effect.

What I was trying to get across, is that beyond the exhaust, filter and chip, doing anything to these cars is disproportionately expensive. As to why, well I guess that, if James will forgive me, the old saying 'You can't polish a turd' - comes into play! Whilst we all love them dearly, the V6 has a multitude of inherent problems that makes impossible an easy upgrade path a-la-Evo. Maybe that IS the challenge and why some of us have been so determined to make headway. In my case, I have used the Proton three times - and won pots twice. The Clio has done 15 or 20 events, the haul being a lowly third in class, once! On that basis, why bother?

Is there an alternative to Sadev? For road use, there would have to be as it will make an appalling companion - check out MikeT's essential earmuffs, I just wear a crash helmet.

Have we looked at alternative components? Yes, one of the rallycross cars has Nissan GTiR running gear, placed longitudinally and Scott and I looked at both Metro 6R4 and Subaru mechanicals. I'm sure that Evo bits could be made to fit too but like all these ideas, the cost and time involved in firstly working out the solution and then fixing all the subsequent breakages is pretty galling. Also, from my perspective, there's only so much you can do without it becoming a silhouette V6, which kind of defeats the object.

Looking at what is 'wrong' with the car, goes a fair way to understanding why it's expensive to improve it - for the road, or competition.

Firstly, the balance is wrong - hanging all the weight at the rear of a short wheelbase car is always going to make handling tricky, particularly when it is reasonably high powered. Ask Porsche, all the time remembering that the flat six sits in-line with the gearbox to get some weight forward - ours are side by side! Then ask yourself how many cars Porsche have made to get where the 911 is today. The Clio is seriously under-engineered in this regard with no volume to spread development cost across.

Along with its short suspension travel, the steering lock is a joke - ask yourself why this was so limited. My guess is that it was to stop inexperienced drivers giving it a huge handful of lock at speed and exiting backwards with chronic understeer followed by snap oversteer when the weight transfers. Those who have not had the pleasure, should spend an hour on an airfield with the car replicating the Mercedes 'elk' test.

Next, the engine is really an asthmatic old lump from the Laguna. As such, it was designed to be torquey, not revvy. Of all my cars, it's the laziest engine of them all and losing all the weight in the crank/rods/pistons is not cheap - and there's six of everything too.

The gearbox, top end and packaging, I made fun of above so I won't do that all over again.

If you are still serious (read stupid and terminally afflicted!) about improving your car, here's where I would concentrate:

Weight reduction - aiming for 1200kg would have the same result on power-to-weight as getting past 300bhp on a 255.
Proper suspension setup - not likely to be less than £3-5K
Breathing mods as discussed.
AP or Brembo brake setup.

After that lot, which could make a civilised fast road setup, MikeT's forced induction would be my vote for big power. Turbo/supercharger heat is more manageable, being more localised and generally higher in the airstream. The engine also has an easier time in the 2000-4500 rev range than mine does at 7500rpm all day long. Bear in mind though that even the sequential box has a pretty low torque capacity compared to the output of a turbo V6 - as Mike's wallet will attest.

Ok, now I have now laid out my madness for all the world to see. Some will see the signs in the mirror but, if it's not too late, run for your lives - or at least enter with your eyes open.
 
totally agree with you on all points but im already part of the way there in for a penny in for a lot of pounds
 
I certainly got the point of your post. As someone who's made big mistakes in what I thought the Vee needed, and who I used to achieve it.

This serves both new and current owners very well. With your consent I will ask Martin to reference this topic with something like "Modding your v6?" in our Knowledge Base
 
T1RBO":1068frtw said:
Is there an alternative to Sadev? For road use, there would have to be as it will make an appalling companion - check out MikeT's essential earmuffs, I just wear a crash helmet.

Have we looked at alternative components? Yes, one of the rallycross cars has Nissan GTiR running gear, placed longitudinally and Scott and I looked at both Metro 6R4 and Subaru mechanicals. I'm sure that Evo bits could be made to fit too but like all these ideas, the cost and time involved in firstly working out the solution and then fixing all the subsequent breakages is pretty galling. Also, from my perspective, there's only so much you can do without it becoming a silhouette V6, which kind of defeats the object.

If you are still serious (read stupid and terminally afflicted!) about improving your car, here's where I would concentrate:

Weight reduction - aiming for 1200kg would have the same result on power-to-weight as getting past 300bhp on a 255.
Proper suspension setup - not likely to be less than £3-5K
Breathing mods as discussed.
AP or Brembo brake setup.

After that lot, which could make a civilised fast road setup, MikeT's forced induction would be my vote for big power. Turbo/supercharger heat is more manageable, being more localised and generally higher in the airstream. The engine also has an easier time in the 2000-4500 rev range than mine does at 7500rpm all day long. Bear in mind though that even the sequential box has a pretty low torque capacity compared to the output of a turbo V6 - as Mike's wallet will attest.


Some more good points here that ive had experience with too. (not in a vee though) Straight cut gearboxes are a nightmare to live with. Not only from the noise but the back lash many of them have. Driving around in 3rd sometimes feels like 1st!! lol Can't beat the noise on a mad blast though [smilie=bowdown.gif]
I completly agree with the silhouette issue too. For the past 5 years ive tried building the fastest Mini in the country using the original 50 year old engine. £20k later and I've had enough. 350+bhp sounds great from an accient 1.4 but it would have cost me a tenth of the price if I were to have used a modern engine like everyone else has. However, then it wouldn't have been a real 1960 Mini. The same as fitting a GTIIR engine to a vee would take its identity away.
The turbo route wouldn't make the 3.0 v6 anyless reliable either as you say. By my own experiance, a 250bhp 1300 turbo is more reliable than a 140bhp n/a 1300. Revs kill engines and torque kills gearboxes.
 
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