What do itb's actually give you, performance wise?

[Russ_16v]

I see a lot of posts in threads asking what increase do itb's give.

So I thought id show this, and hopefully give an idea of what they actually do.

While they might not give a massive increase in bhp/torque at peak, the way they change the power delivery is like night and day:



The easiest way of showing this difference is in the graphs.

When lightly tuned (Filter+cat back exhaust) mine had a max of 149 lb ft at 5500 rpm, now due to the itb's and good mapping its making 150lb ft at just over 4000, and holds close to 160 till close to 7k.


Here is a graph when standard, the torque is on the right, and it peaks just on 150 lb ft at 5500 rpm, with a very 'up and down' torque curve.

Here is the curve after the itbs, the power is like a line, and the torque curve is completely different

I then made a few more changes, such as moving the air temp sensor into a trumpet, plus a few other things, and had the map tweaked again and the curve got even better:

although its not gained a huge amont peak power/torque, its now making between 15-20 bhp and lb ft of torque more at any given point in the rev range, completely changing how the car dives, and explains why its so much faster.



Timed performance has gone from 0-60 in 6.7 secs average, to 5.7 average, and 1/4 mile from 15.0 ish to 14.2

I hope that may explain it

 

[DanFreemanPhoto]

How much did your ITBs cost in the end?

For me, the standard kits are a waste of money for the power increase. There's much better ways of spending £2k+ if you have to.

 

[furio-james]

In my experience of throttle bodies, having them on my Saxo, the low down tourque increase and flatter tourque curve makes driving alot more pleasureable and power delievery is quicker and you dont need to rev the nuts off it so much!

Although the figures may not blow you away it certainly makes a big difference to the engines characteristics.

Oh and theres the sound! mmmmm . . .

 

[Tony Hunter]

Got to be the worst "Iv'e got throttle bodies" thread ever.

 

[Russ_16v]

How much did your ITBs cost in the end?

For me, the standard kits are a waste of money for the power increase. There's much better ways of spending £2k+ if you have to.

Around £580 quid mate

In my experience of throttle bodies, having them on my Saxo, the low down tourque increase and flatter tourque curve makes driving alot more pleasureable and power delievery is quicker and you dont need to rev the nuts off it so much!

Although the figures may not blow you away it certainly makes a big difference to the engines characteristics.

Oh and theres the sound! mmmmm . . .

True, so true lol

Got to be the worst "Iv'e got throttle bodies" thread ever.

Shhh you :rasp:

 

[Hutchie]

you could of summed it up with,
boddies make me well quicker innit and i always has a huge smile when i boot it

 

[Russ_16v]

I thought for once id bve a bit more informative for once lol

 

[marc1330]

Gotta agree with you Russ had em on now for a couple of weeks and the car is so much more tractable. since having mine roaded a while back with remap inlets etc to now the difference between top figures aint massively different but if you look at the graph and how it drives on the road its like night and day

 

[furio-james]

Got to be the worst "Iv'e HAD throttle bodies" thread ever.

you could of summed it up with,
boddies make me well quicker innit and i always has a huge smile when i boot it

In a nut shell!

 

[shiyan]

Around £580 quid mate

Eh? You bought them for 580 pound... is that 2nd hand? I thought throttle bodies + required ECU would be close to 2000 pounds new?

Is fuel use much higher as a result?

Very impressive results though, I must say.

 

[Russ_16v]

No mate, that was the whole conversion, Im the first to make it work on standard ECU. (bear in mind that includes the money back for the bits I sold that I didnt need any more)

Fuel is more when driving hard, just as good, maybe even a little better, over 40mpg on a run

 

[shiyan]

No mate, that was the whole conversion, Im the first to make it work on standard ECU. (bear in mind that includes the money back for the bits I sold that I didnt need any more)

Fuel is more when driving hard, just as good, maybe even a little better, over 40mpg on a run

Oh wow, will you be selling the conversion kit? How much would it cost for someone to replicate what you did?

 

[Harpham]

Oh wow, will you be selling the conversion kit? How much would it cost for someone to replicate what you did?

+1 how much would it cost overall to buy/fit throttle bodies?

 

[shiyan]

reading up on the conversion thread now...

 

[Russ_16v]

All depends really, Id say its do-able for under £1000 if done right, though it all depends on a lot of factors, from what itb's you buy, what inlet mani you choose etc

So it could be very cheap, or upto£1500 ish, though still cheap

 

[Tom@JMS]

Its difficult to compare the two sets of results directly because if you look at the torque resolution on the two separate rolling roads it is very different. The res of the original rollers is fair greater hence the peaks & troughs on the first, and the seeming flat line on Paul's setup.

You also need to be careful with the cost estimation too as I'm fairly sure you have saved massively on the calibration work.

It's a brilliant project though. Something that should have been done years ago, instead people were pushed towards non OEM ECUs.

 

[Russ_16v]

Its difficult to compare the two sets of results directly because if you look at the torque resolution on the two separate rolling roads it is very different. The res of the original rollers is fair greater hence the peaks & troughs on the first, and the seeming flat line on Paul's setup..

Im back on these rollers this coming weeked so il post the results up

You also need to be careful with the cost estimation too as I'm fairly sure you have saved massively on the calibration work

The estiamation is exactly that matey, an estimation If you sold all your original kit, like inlets etc, and keep an eye out for good deals with the parts then you could do it for under 4 figures easliy - on the other hand, if you wish to keep your standard bits etc then the cost will be higher.

It's a brilliant project though. Something that should have been done years ago, instead people were pushed towards non OEM ECUs.

Thank you for the kind words mate its getting there, Still needs a little more fiddling to be 100%, but im 95% there

In fact id love to show to you boys at some point see if there is anything you can suggest that I can improve on - Im always willing to listen

 

[Russ_16v]

Oh, this wasnt meant to be just about my itb's guys and girls, its more of a general idication of what itb's do, as we only tend to see power figures, which really do not show what a big difference they do make.

 

[Ralphizzle]

Hi Russ,

So... the 1st graph is without the ITB's i presume as to 'standard'.

Quite a gain!

 

[Russ_16v]

Yes mate, though they are on 2 different rolling roads, this coming weekend im back on the first set of rollers so I will be able to accurately say how much its gained

 

[Cro]

I run omex and I did my conversion under £1k that does not include anything like selling parts not needed anymore etc. So as Russ says completely possible.

I'll have a graph from the place I first took my car to soon aswell so I'll throw that up for comparison too

 

[Russ_16v]

That will be great mate