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MG MGF Technical - TTB What bhp gains

What gains would you expect from fitting a TTB and a K&N to a 18.i. Has there been any test yet. Mike Satur Site cliams about 25bhp But this was with a closed air box.
Dave

Whats a TTB?
Dot

trophy throttle body
Will Munns

The TF with the TTB (Trophy Throttle Body!) is giving 135bhp (or 160bhp for the VVC) so I would have thought that this would give a fairly good idea of the gain to be made to a F.

Jason H
Jason H

with modified cams though

Will
Will Munns

OK, I had to check we weren't talking about different things - but 25bhp from just the addition of a TB and an air filter sounds rather optimistic to me!

For the Elise, an increase of about 2bhp has been measured from the TB alone. Although it feels like more.
Dot

Will,
I hadn't realised that the mpi TF has modified cams - I have a VVC and certainly belive that my TTB and K&N has given me the extra 15bhp that a TF VVC has.
Jason H
Jason H

Dot,
Although I have not had my F tested on a dyno, I had ny previous car regulary tested as its performance was enhanced, and so am fairly aware how noticeable the performance changes are with extra bhp. I am sure that the addition of a K&N and a TTB to my VVC has given a lot more than just 2bhp.
It would be really interesting to re-run the airfilter test as discussed before with all the new filter arrangements available, but also add in the extra dimension of standard versus Trophy TBs.
Jason H
Jason H

I am suggesting roughly 2bhp for the TB alone, I can't remember the figures for the K&N. I'm sure Rob Bell or Dieter will be along shortly...
Dot

It's very hard to judge BHP gains from just driving, the difference in sound, could make you feel you're going faster, you'll always be optimistic of any performance gains. heck even the shoes you wear can make the car feel completely different.
Kingsley

Don't forget the "deep shine" effect!

Will
Will Munns

Kingsley,
I agree that it is almost impossible to guess the extra bhp just from driving
In my case I have a number of road sections which I have measured and I regularly note my time and speed over (a bit of an anorak!)and from the increases I gained on my prevous car against the known power increases, I am pretty sure that the time and speed increases I have seen from my F since fitting a TTB must be more than 2bhp - that would be lost in the innaccuracies of my timing methods!
Jason H
Jason H

Purely subjectivly, having gone from VVC with K&N to VVC with K&N and TTB, I am not to sure about extra Bhp at the top end (but then I don't red-line it). But it feels much better response in the mid range 3-5K.

Paul
Paul

K+N 57i = +8bhp in a 1.8 MPi / +15bhp on a VVC according to the MG Enthusiast tests, by some of us on this BBS.

TF 135 also has Trophy 160 induction set up and exhaust system. So, assuming 5 for the new air filter arrangement (extra air intake directly to the air filter box), 3 for the exhaust leaves 7bhp to find from the TB and the cams. From experience, the cams do not add much of an actual bhp gain, they just make the car pick up faster, making it feel more powerfull. I would say between 3 and 4 for the cams - leaving 4 or 3 for the TB.

Although this doesn't take into consideration any possible changes to the MEMS (anyone know if there are any?) this i think is a reasonable guess. The air filter estimate may be a little generous as the filter still has no direct cold air feed, however the additional intake 'should' get rid of the torturous route the air normally follows and should help to make the most of the extra few mm diameter bore of the TB. The exhaust figure is an educated guess based upon the results of the MG World Exhaust test. MGR still have to comply with drive by noise regs and therefore the Trophy system isn't anywhere near as loud as the aftermarket ones, suggesting more internal baffles to absorb the noise.

Just an educated guess.

SF
Scarlet Fever

Trophy TB will make the car feel more responsive to the accelerator as for the same amount of pedal depression you are getting a higher rate of air flow into the engine.

Standard TB internal bore = 48mm
Trophy 160 internal bore = 52mm
GM TB internal bore = 55mm

So, i've ordered the GM one. Needs some 'fettling' to get it to fit, but should be better still, especially with the ITG Maxogen i've ordered. :-)

SF

P.S. Message to Rob Bell.

Had some minor design problems with the 'home made' air box regarding the 'universal' seal around the various air filters where they enter the box. I need a new filter anyway, so i have taken the plunge and ordered an ITG Maxogen to see how they did it (get some ideas) and fit to Scarlet after. Be interesting to do a direct comparison RR test with each box design (and maybe your heat shield and flower pot mod) at some point in the future. We could also try to get hold of a PiperX (Viper is it?) and Hurracane.
Scarlet Fever

I'll have my Hurricane fitted by the time I do the MG London to Brighton run if you fancy a Butchers (no I'm not doing the MG run in an Elise though! :o)
Dot

>I'm sure Rob Bell or Dieter will be along shortly...

Nope, not me. Dyno Test is out of my budget. I'd prefer adding other 'dark side stuff' instead ;)

But I think Scarlet can do soon ;)

Mate, the package is on the way to Essex.
Ball joints, fork heads included.
I cut as well 2 pieces of 3mm aluminum (80x30mm) for the Sensor flanges DIY and packed it to the package. *thank you*<>*your welcome*
You only need to watch out for the postman and get a piece of aluminum sheet metal 125x150mm as drawn on http://www.mgfcar.de/throttle/throttle10_t.jpg
Garden hose pieces from mothers farm should be also no problem.

Wanna see Scarlet breathing free :)))
:oD
Cheers
Dieter
PS. I think it's only a few more bhp, but more torque ?
Dieter Koennecke

To be honest the figures are really meaningless to most of us. I think the point is for most of us is, does it feel better to the driver. Fast throttle response, torque and BHP can all contribute to how the car behaves and feels. You can have massive BHP figures but if you don't have the throttle response or torque then the car will not be perceved as so powerful by the driver.

Personally I find the G Forces generated while going round corners fast the most fun part of the F. Being pushed out of the corners by the rear wheels is just such a great feeling for me.
Tony Smith

Donut quustion - what is the purpose of a throttle body and the pros in upgraging ???

Cheers

A Donut, in Biscuitville.
Jeff Newman

Throttle, limits air going into engine in order to limit power.
Throttle body holds throttle.
Problem is that at fully open throttle a samall throttle body still restricts the air, restricted air means less pressure before combustion, and so means less force when expansion due to burning happens. By getting a wider throttle the air flows better and you get a hight pressure in the cylinders, giving more power.

Performance air filters work in a simmiler way.

Will
Will Munns

If more air is being let in would it not be an idea to let a bit more fuel too or is that sorted out by the MEMS?!

An other Donut
tim

Yes the MEMS shold adapt slightly, however if it dosn't adapt enough then the fuel will burn lean (and therefor hot) which is bad. The MEMS adapts using an oxeygen sensor in the exaust. Once the max fueling that the MEMS can give is exceeded you need to start adding other mods to incresse the fueling, such as a power boost valve or diffrent ECU.
However the diffrence caused by adding an aftermarket filter and TTB is not expected to be enough to make the mixture lean.

Will
Will Munns

MEMS will cope with the TTB.
Dot

MMMMMMMMM............Donut.......
Homer Simpson

25BHP??Did I say that?
The manufacturers claim a 10% increase in BHP with the PiperX viper couple this to a 52mm ( or larger) TB and the 1.8i will feel a lot more responsive certainly on a par with a standard VVC up to a point as the VVC will breath better higher up the rev range. fitted to a VVC the improvements will be noticable above 3500rpm, especially when the VVC kick in.
HTH.
Mike.
mike

>to let a bit more fuel too

Yes, it does from my 10 month experiance. 0.5 liters on 100km (I'm sorry for the wrong measure, someone may convert to 'true' miles per gallon)
No gain, no pain :)

With Tony on that better feeling point. BHP is anyway 4me. If I'd like to get huge BHP, than I'd get a TVR Chimera ;)

Loved the mad DIY works with the GM thingy also the other year. See archives how it began in June?.

Cheers
Dieter
Dieter Koennecke

Dieter,

Woohoo! :-)

Thanx mate - you are a star!

I assume i still need to drill the mounting holes slightly? (i've been reading your web page). So, all the preparation work i need to do is...

Get hold of a length of hose - I'm gonna try and get hold of a nice braided hose (like the Elise on your web site) :-)

Fabricate the throttle cable bracket - all taken care of.

Drill the new mounting holes.

This should be fun, i'm looking forward to some more hands on modifiying :-)


------------


Mike,

Any news on the ITG mate? If Dieter's TB gets to me all the way from Germany before your Maxogen kit arrives from Wombwell, how will you live the embarassment down! (could always blame 'consignia' i suppose!!) ;-)

SF

Scarlet Fever

Attention to the matter please.
SF get's desperate and itchy hands also.
LOL
Dieter Koennecke

:-)

SF
Scarlet Fever

Scarlet

You can probably answer this one.

How did the TTB affect the ICON?

The ICON from what I understand, merely advances the timing of ignition, will resetting the MEMS (bashing the throttle a few times) still work .

So far I have MS exhaust, K&N and the ICON on my MPi but fancy the idea of the TTB too. I suspect I would need to stick the car on the RR again....!
What was your experience.

Thanks

Tim
tim

Tim, I'd certainly recommend that you do get the car re-tuned on a RR when you add the new TB.

I want a GM TB, but as the Sprint regs prohibit even the TTB, the GM item is out of the window. Bah!!! :o((

Maybe road-going modified for next year? ;o)) That'd allow a couple more mad dark-side mods!

>>Had some minor design problems with the 'home made' air box regarding the 'universal' seal around the various air filters where they enter the box. I need a new filter anyway, so i have taken the plunge and ordered an ITG Maxogen to see how they did it (get some ideas) and fit to Scarlet after.<<

That is a tricky area, I agree. I reckon that the inlet should form an interference fit to the tube connecting the filter to the TB (need to measure the outer diameter of the K&N/ ITG tube and go from there- about 74 mm IIRC). Great idea to go for the Maxogen! Had a bonus recently mate? LOL

Have a look at http://www.mgf.4mg.com/new_airbox.htm - this is what I am going to use to prototype our 'home-made' airbox. Dimential correct, but without the inlet throat to accelerate the airflow... All I need is some time, and space to work on it...
Rob Bell

Although i have an ICON, it has been sitting on my 'MG bench' for nearly 5 years now, i was going to fit it, but then i started hearing about Dirk's experiences and decided against it. The ICON chip intercepts the signals from the MEMS and then adjusts them to suit its 'map'. These signals are then passed to the engine, where the effects are felt. From here however, i am not sure what happens. I assume that the feedback to the MEMS from the sensors in the engine are also intercepted by the ICON where they are reverted to a normal signal. If this doesn't happen, then the MEMS would recieve signals showing the ICON's effects and compensate for them. This would set up a viscious circle, with the MEMS effectively cancelling out any input from the ICON unit. Given that the MEMS automatically adjusts its signals to suit the TB, then the ICON would receive adjusted signals from the MEMS, therefore i doubt the ICON would need re-mapping. Of course i am only surmising, but the above seems pretty logical to me.

The GM throttle body is 'en-route' to me as i type this (in fact it MAY already be at home waiting for me to finish work). So, at the moment i can only theorise as to the effects, most of which is written above in previous postings. The standard MEMS 'should' be able to cope with this as within set perameters, it is more than capable of running the majority of 'bolt on' goodies. There are exceptions, multiple throttle bodies and the TT Supercharger spring to mind, but these are quite radical items changing the way the engine functions in a fundamental manner as opposed to improving the efficiency of the engine in the way an air filter, TB, exhaust etc do.

---------

Rob,

The problem i have been having is the external diameter of the pipe that connects the filter to the TB. The K+N has a fiarly substantial 'quarter' radius pipe, whereas the original ITG has a thinner section 'half; radius pipe (the standard PiperX has no pipe at all!) This means that the home made affair not only needs to be supplied with a 'mounting kit' to suit the type of filter you already have, but also needs to accomodate the different external diameters of the 2 main pipes. A couple of solutions spring to mind, one is to simply supply a replacement pipe with the airbox, the other is to come up with some way of adjusting the diameter of the airbox where it meets this pipe in such a manner as it retains its airtightness. A flexible rubber collar and a jubelee type clip would do this, but then you need to mount the air box firmly at the other end as it will not gain any support from the pipe. This is fine until you realise that the two pipes effectively position the air box in different places within the engine bay (one being a quarter turn and the other being a half turn). Hence the need for a mounting kit. Anyway, i think ITG have gone down the 'supply thier own pipe' route, we i feel should try to use as much of the original air filter kit as possible (to try to keep costs down). So The upshot of this is, i needed ideas AND a replacement filter (hence the Maxogen). I am hoping to be able to get some idea of the mounting kit design shortly (i am toying with the idea of a simple bracket which you screw to the underside of the engine bay (not the inspection cover!) The bracket will be different depending on which air filter you have as the position of the airbox dictates the route of the intake air pipe and thus the angle the intake pipe enters the box.

Phew! I hope this makes sense mate :-)

SF
SF

Hi Andy,

I get what you are saying WRT the sealing of the filter to the airbox.

Here's my solution that would not necessarily require the supply of a tube: the airbox should seal around the filter - the section into which the metal collar inserts, and the jubilee clip fastens. The outer diameter of this section seems to be the same on the Pipercross and K&N filters I have- although I cannot comment on the ITG. I'll have to have a look - are you comming along to the Luton meet next week?

Also, I don't think that the seal needs to be completely air tight, so long as the hot air 'bleed' into the airbox is not significant compared to the cold air supply - this is based on the surprising effectiveness of the heat shield that I use currently.

However, I think you may be right- supplying an 'induction tube' with the airbox may be the best option as this would aleviate the need for different mounting positions with various aftermarket filters (different lengths of alternative TBs notwithstanding! ;o). A VVC specific pipe and a 1.8i specific pipe may be required given that the TB is mounted in a different position depending upon the inlet plenum fitted...

I'll try to remember to bring along the Rover airbox to the Luton meet, as I think this explains some of my current thinking quite well :o)
Rob Bell

Not sure about the Luton meet at the moment, there is a strong posibility that i will be doing surveys in the westcountry Tuesday/Wednesday/Thursday next.

The good news is that my ITG Maxogen arrived today (thanx Mike!) and already have an idea or two around the problem. The ideal AFAIC is to have the airbox mounted in the same position for all model / air filter / TB variants and the only way i can see this happening is to supply a connection pipe from the box to the TB that is specific to each model / TB / filter. By my calculations that breaks down as follows:

MPi + K+N + standard TB = pipe length A
MPi + K+N + Trophy TB = pipe length B
MPi + K+N + GM TB = pipe length C

MPi + ITG + standard TB = pipe length D
MPi + ITG + Trophy TB = pipe length E
MPi + ITG + GM TB = pipe length F

MPi + PiperX + standard TB = pipe length G
MPi + PiperX + Trophy TB = pipe length H
MPi + PiperX + GM TB = pipe length J

VVC + K+N + standard TB = pipe length K
VVC + K+N + Trophy TB = pipe length L
VVC + K+N + GM TB = pipe length M

VVC + ITG + standard TB = pipe length N
VVC + ITG + Trophy TB = pipe length O
VVC + ITG + GM TB = pipe length P

VVC + PiperX + standard TB = pipe length Q
VVC + PiperX + Trophy TB = pipe length R
VVC + PiperX + GM TB = pipe length S

A full 18 pipe variants!!! Admittedly there may be some overlap of dimensions and the K+N and PiperX being similar designs are likely to be the same but this could be a major headache. One solution that presents itself is to have the filter attached to a standard length pipe and the airbox sleeving the pipe. In this way all filter/plenum/TB variants could be accomodated, as the differences would be taken up by the amount the air filter projects inside the airbox. The downside is that it would tend to make the airbox that much bigger, making it more difficult to DIY fit (and it doesn't get round the sealing of the pipe end problem either). A rubber 'skirt' around the end will probably do the trick and if the airbox is mounted at the fuel pump end then there is probably no need to use a jubelee clip. This is the avenue i am currently pursuing and is the one that looks the most promising given all the variants.

SF
Scarlet Fever

Andy, I am sure that this number of variants are unnecessary- luckily!

For starters, the external dimentions of the standard and Trophy TBs are identical.

Secondly, all filters I have come across use the same internal diameter oulet - that being 70 mm. The primary differences in terms of the induction tube are length and the angle of turn. Given that these are specified no more scientifically than 'oh this is what is lying around in the store room,' 'it'd be a jolly good idea to have some kind of bend in the tube to smooth out air flow' and 'right we need to get this mother to fit into the space available' we could settle on a single design of inlet tube, with the four variants being:

1.8i inlet plenum - standard or Trophy TB
VVC inlet plenum - standard or Trophy TB
1.8i inlet plenum - GM TB
VVC inlet plenum - GM TB

One thing though - if the airbox is to be rigidly mounted (and ours would have to be) we'd need to use a flexible inlet. One option would be to re-use the standard fit flexi-tube. Not an ideal solution by any means. An alternative is to use the same flexi-tube that ITG use, but I've no idea where this is purchased from :o(
Rob Bell

Progress...

OK, i have now finalised the revised design details and have given the drawing to the fabricator (well, his missus anyway!) along with the ITG box - for inspiration.

To get over the above problems i have used a straight length of 70mm dia pipe (hey, it works for ITG and who am i to argue!) and a rubber seal. This means that the box completely encloses the entire filter and the pipe projects out through the rubber seal. This allows the pipe and the box to 'telescope' to suit whatever plenum/filter/TB combination you may have, the seal also compensates for any differntial movement between the box and the engine - clever eh?

I have exported the drawing as a JPEG and can send you a copy Rob (or i could post it on the X-Power forum and link to it from here.)

Downside is that the fabricator has just picked up a large order (for oxygen pipework and 'sockets' for installation in people with emphasymia <sp?>. They can wander around thier home and plug into the system when necessary), so i am not sure when the prototype will finally be available.

SF
Scarlet Fever

Hmmm, maybe i should cut and paste this lot into a new thread. It is certainly 'off topic' here.

SF
Scarlet Fever

Hi,
didn't read and understand all you'r doing there, but I think I know what hose you are after.

Is it this material ?
http://www.mgfcar.de/airfilter/hartmut_airf2.jpg
Picture courtesy Hartmut ??? a german Elly enthusiast.
He got such hose at a shop for standard rubber parts. (Not what some may think).
I know one in 'Essen' just behind the main station. ;)
OK forget that. But an option will be to look for such shops with technical rubber parts, foam mats etc.

HTH
Dieter
PS. Andy still no postman ?

Dieter Koennecke

This thread was discussed between 19/03/2002 and 22/03/2002

MG MGF Technical index

This thread is from the archive. The Live MG MGF Technical BBS is active now.