766 replies to this topic

[Crispy]

Crispy, you have probably already said this but at what stage of tune was your car at before having the throttle bodies fitted?

TMS stage 2+

[markv]

What I personally would like to know is what we are comparing here. I read Crispy's posts and they sound very postive. But is this the same as the power pack 4? And is the power pack 4 the standard engine, with throttlebodies and different ECU? Or is there also a differenct exhaust? Description of the power packs on the TMS site is very clear, up to the throttlebody conversion As it reads now I would assume everything is standard except the throttlebodies and the ECU. Then again, assumptions Mark

[Silverback]

Maybe it's just mine or my interpretation of the engine, but my standard NA doesn't feel like anything much is happening below 3,500 so I end up having to rev it in any case, so a change in driving style wouldn't be required for me!

[~PHIL~]

sounds similar to an S2000 experience, - having to rev the nuts out of it etc

[Winstar]

Crispy, you have probably already said this but at what stage of tune was your car at before having the throttle bodies fitted?

TMS stage 2+

Now I'm confused,

So if you had a stage 2+, then where do the graphs come from?

Or is that +30 bhp including a Miltek? if so is that included in the £3k?

[Scotsdave]

People keep asking about previous state of tune and I think thats fairly irrelevent. Tms stage 2 is what? A milltek, remap and induction kit? If you go with throttle bodies your binning the remap as your using a standalone ecu, the induction kit is binned too as your replacing the whole inlet! I used to have a redtop on throttle bodies (sbd 196 kit) and Crispy's description is spot on. You can't really be lazy with a throttle bodied engine. You'll find yourself changing down alot to get the best from the setup. But nothing can beat the noise and rush from reving the engine. If it's lazy torque you want then you need to get a SC or a turbo. I personally like revving an engine but it can become tiresome day to day.

[RichH]

People keep asking about previous state of tune and I think thats fairly irrelevent.

Tms stage 2 is what? A milltek, remap and induction kit?

If you go with throttle bodies your binning the remap as your using a standalone ecu, the induction kit is binned too as your replacing the whole inlet!

But not the exhaust which is the main unanswered question here. That's another £1150 ish on it's own excluding fitting! Is that included in the £3k or not? I doubt it and without it you won't get the results shown in the published graphs which are being displayed as what you might get with the £3k kit.

so no, it's not irrelevant.

edited to add, that it you need to pay extra for the exhaust then that wil push the cost to nearly £4.5k to get the results in that graph, and comparing that to the S/C route which has more power and a hell of a lot more torque for a similar price, you'd better be happy with the noise it makes!

Edited by RichH, 01 June 2007 - 10:20 AM.

[Scotsdave]

People keep asking about previous state of tune and I think thats fairly irrelevent.

Tms stage 2 is what? A milltek, remap and induction kit?

If you go with throttle bodies your binning the remap as your using a standalone ecu, the induction kit is binned too as your replacing the whole inlet!

But not the exhaust which is the main unanswered question here. That's another £1150 ish on it's own excluding fitting! Is that included in the £3k or not? I doubt it and without it you won't get the results shown in the published graphs which are being displayed as what you might get with the £3k kit.

so no, it's not irrelevant.

But the manifold was never used in previous states of tuning? As it's only been released

[SteveM]

It appears Crispy's car already had a Milltek fitted (being stage2), but I think for the sake of clarity does it make any difference for the stage 1 TB kit? too slow!

Edited by SteveM, 01 June 2007 - 10:22 AM.

[VIX]

You can't really be lazy with a throttle bodied engine. You'll find yourself changing down alot to get the best from the setup. But nothing can beat the noise and rush from reving the engine.

Presumably when you're driving "normally" there's no difference, you only have to keep the rev's up if you're maximising performance? Or do you find yourself changing down more all the time?

[RichH]

But the manifold was never used in previous states of tuning? As it's only been released

But the cat etc was.

[Scotsdave]

You can't really be lazy with a throttle bodied engine. You'll find yourself changing down alot to get the best from the setup. But nothing can beat the noise and rush from reving the engine.

Presumably when you're driving "normally" there's no difference, you only have to keep the rev's up if you're maximising performance? Or do you find yourself changing down more all the time?

I found I couldn't drive the car like I used too. For example sitting on the motorway at 70 sitting at 3000rpm before tb's i could press the accelerator and the car would pick up quite quickly. On throttle bodies it wouldn't pull away quickly like before, instead you drop it a cog and it would pull away.

This was a fully mapped set up relining at 7800rpm. I also had the sbd type c manifold and a 2.5" exhaust to suit the setup.

I had the set up for 2 and half years and the car was really reliable just a little tiresome at times to drive as it was my daily car.

Edited by Scotsdave, 01 June 2007 - 10:33 AM.

[PaulCP]

Now this is by no means having a "dig" (actually i am please that there is another alternative for those of us that don't care for turbo power ) but a genuine question to those in the know. Ignore the actual figures they are plucked out of thin air & don't relate to any graphs etc but is developing 190bhp at 7000revs more stressful on the enging than developing the same power at say 4000revs. Obviously the latter means more torque so puts different stresses on the engine/transmission components but which, without other internal mods is the better for longevity

Edited by PaulCP, 01 June 2007 - 10:34 AM.

[Winstar]

Now this is by no means having a "dig" (actually i am please that there is another alternative for those of us that don't care for turbo power ) but a genuine question to those in the know.

Ignore the actual figures they are plucked out of thin air & don't relate to any graphs etc but is developing 190bhp at 7000revs more stressful on the enging than developing the same power at say 4000revs.

Obviously the latter means more torque so puts different stresses on the engine/transmission components but which, without other internal mods is the better for longevity

the easy answer is yes as a large proportion of the force a conrod experiences is due to acceleration and deceleration obiously this increases with engine speed.

I may get flamed for this but from the descriptions of driving a TB'ed car is this not just the same as an elise 111R with the toyota engine? low torque and all the power at high rpm?

[jasvxt]

Personally i wouldnt bother with throttle bodies in the first place, too expensive for little effect, if you want more power supercharge it or by a turbo IMO Isn't something happening on S/c conversion prices anyway ?

[Jase_MK]

Back to the charts, was the same car used for the before and after plots? Only on the std plot the car looks a bit sick, only producing 138 bhp instead of 145-147 bhp.

I thought Chris's stage 2+ car was used for the graphs. So either the comparison graph shows two different cars which isn't really on or stage 2+ was only producing 138bhp...

[techieboy]

Back to the charts, was the same car used for the before and after plots? Only on the std plot the car looks a bit sick, only producing 138 bhp instead of 145-147 bhp.

I thought Chris's stage 2+ car was used for the graphs. So either the comparison graph shows two different cars which isn't really on or stage 2+ was only producing 138bhp...

The stage II+ charts on the TMS site are from my recently fitted conversion. At the time of the dyno run, I was initially disappointed with the "numbers" as I'd convinced myself I should be looking at circa 170bhp from the various numbers in the Stage I and Stage II. However, as somebody mentioned earlier in the thread, the proof is in the driving. It's a much nicer drive than the standard and pulls with much more urgency all the way up to the redline.

Had considered the TB conversion as it was just coming off the trailer whilst I was at TMS but I'm not convinced that the additional 6-8bhp on the TB charts is worth the cost. But I almost set on the new manifold asuuming it doesn't ferk with the low down power delivery. Plus, I don't really want to bin £300+ of ITG induction.

[JG]

Paul, I think I'll have a go at answering that question as i studied engine wear as part of a degree. power = torque *rpm If you use SI units it works out nicely, if you use bhp, hp, ftLbs etc etc then there will be a fair bit of unit manipulation required. The above is obvious when you consider that if you want power you either need to up the rpm or the torque. Upping rpm is a fairly basic concept in that to most of use its a fairly tangible thing. In practice its a little more complicated. Upping the torque is even less tangible but for example an engine that had a long stroke, small bore will be 'torquey' and an engine with a short stoke low inertia large bore will be revvy. And so to wear rate. There are a number of issues when considering wear rate. The first is that is it not a direct correlation with reliability. Reliability of an engine could be considered to be ‘how many times it lets me down on the side of the road in 1 year’ but generally those reliability issues are not terminal. It might for example be that the water pump has worn out, etc. All these things are easily replaceable. What I am trying to get at, is ‘wear’ that will in effect lead to the end of the life of the engine before it requires a rebuild or that the failure is catastrophic enough to require a new one (con rod through the side of the engine for example). The first point then is bearing wear (big end, main bearings) etc. The bearings on an engine work through a soft surface (usually white metal) running against a hard surface (annealed steel) with a oil feed constantly providing a flow to the bearing surface. When the bearing surface (white metal) wears the ‘gap’ the oil has to flow through gets lager and the oil pump therefore struggles to provide adequate flow and the pressure drops (hence low pressure oil engines being considered knackered). The second point is stress and strain in the component parts. Take for example a conrod, as it flies backwards and forwards, with a great bang every other time, it fatigues the metal. The structures in the metal eventually become in-coherent and the item fails. The same can be said for the crankshaft etc. (the term strengthening the bottom end usually means finding a better manufacturing process for the crankshaft and using better bearings). Stress and strain on the component parts can be testing in laboratories. Generally they are over specked for an engine. Supposedly our ecotecs are good for 250bhp on standard internal parts. I'd be a dubious as to how those figures were derived but lets say it was tested and accept it. They also say there are good for 200,000 miles, that is when the engine bearings will be worn out enough that it is beyond economical repair. All this to say that wear rate of an engine can be measure by collection of the 'bits' that fall off. Through careful filtration of the engine oil a weight of material can be measured. The bearing surfaces are also measured with laser and the results are correlated. Finally then research suggests that wear rate is a cubic law with rpm under load. Therefore if at 1000 you are getting x amount of 'wear' at 2000 you are get 8x and at 7000 you get 343x. that said you only actually spend fractions of seconds at 7000. Of course knowing this I drive the car with a fair amount of mechanical sympathy and rarely venture above 6k rpm. Edit: slight number issue

Edited by JamesGray, 01 June 2007 - 11:24 AM.

[Crispy]

You can't really be lazy with a throttle bodied engine. You'll find yourself changing down alot to get the best from the setup. But nothing can beat the noise and rush from reving the engine.

Presumably when you're driving "normally" there's no difference, you only have to keep the rev's up if you're maximising performance?

Spot on (apart from the noise)

[Thorney]

Yeah I guess I should separate out the non TB stages from the TB stages, its getting complicated as they can obviously mix and match which gets confusing. Think I'll do a separate page and have them come together as it were as they mix? As regards charts, yes they show a standard to stage 1, we put crispy's back to stock for power runs then fitted the tb kit to get a good comparison. Stage 2 to TB kit would be less pronounced on the chart but still feel the same in terms of delivery on the road.