Roosie

iTrader: (8)

i have a std throttlebody on my 2wd is there a larger replacement available ie rs500 any others?

Chip

iTrader: (3)

What inlet do you have?

GARETH T

my advice would be dont waste your time on throttle bodys, there other places that can be improved to give real gains!

Mike Rainbird

iTrader: (3)

What he said. The standard size throttle body will actually flow well into 600bhp.

The inlet can see significant improvements by replacing it for an EECIV item - but good luck finding one at the moment, as everyone wants one!

Roosie

iTrader: (8)

swedish type inlet im using

Mike Rainbird

iTrader: (3)

If you have no choice in changing because of clearance reasons, then we do a slimline version that is bigger than standard (designed to go with the Swedish plenums when fitted in Escorts), but if you have no such issues, then there is really no point in changing at your anticipated power level.

Garage19

If you go larger throttle body you will loose throttle control at smaller throttle openings.

Can be very bad for track work.

Mike Rainbird

iTrader: (3)

Agreed, if it is too big .

Chip

iTrader: (3)

Vectra V6 is same size as RS500 and costs pennies, and has a wedge attached to it to make the opening non linear so you still get good control at small throttle angles.

Garage19

I think it is funny that people pay a fortune for 60mm eec TBs when you can unbolt a 60mm one from any 2ltr zetec in a scrappy for a fiver.

I have also used 535 BMW ones in the past which are 65/67 from memory. and are easy to fit and convert to other TPS.

jb fletch

iTrader: (1)

I've got an EECIV throttle body on my Swedish plenium & had to space it away from the plenium as the throttle linkage fouled. I also had to make up an adaptor to fit the Weber TPS & make up a plate to cover the Idle Control Valve as I didn't have one !!

I now got an ISCV from B9COS Thank you very much !!

jb

Chip

iTrader: (3)

Its cossie owners, all spending on trendy bits and utterly no creativity, that how they roll typically

jb fletch

iTrader: (1)

Not me !! Bogg it all the way as you know Chip !!

jb

Mike Rainbird

iTrader: (3)

Obviously some of the normally aspirated throttle bodies are not suitable for forced induction, as they weren't designed to take possitive pressure / high temps.

So you have to be careful about picking a suitable TB that won't leak or have the throttle butterfly jamming, due to it being made out of the wrong material, so expands with the heat of the charge air and fouls the throttle body and potentially jamming open or closed - something many DIY'ers forget....

Coincidentally, the slim-line / larger version that I sell, addresses these issues .

http://www.randbmotorsport.co.uk/sho...?ProductID=273

Garage19

You are right Mike, sealing was an issue i was concerned about too.

A n/a TB will only ever see vacum so i was concerned how their seals would cope with positive pressure.

However having tested them with a compressor and some soapy water i'm happy both the ones above will hold 2 bar.

Chip

iTrader: (3)

Likewise, tested N/A ones and never found a problem, im sure it can be in some instances though, just not ever managed to find an example where it is.

What N/A ones have you found that leak then Mike? So people know what to avoid?

Mike Rainbird

iTrader: (3)

Some of the larger BMW / Volvo ones (I was actually lead to believe that the 535 ones leaked if unmodified), which are popular with the Scandinavians .

The above one I sell, is a n/a one modified to suit Cossie TPS's and forced induction... .

Garage19

Most of the 535 bodies used are 20ish years old now so always worth checking for leaks.

It is an interesting point you make about expanding butterflies jamming Mike.

My point of view on that is that the OE manufacurer will have looked at thermal expansion coeffecient of the butterfly material and allowed enough room for it to expand upto at least 100 deg as this is what the engine runs at and in theory the TB may nearly reach this through heatsoak via the manifold.

The last thing a manufacturer would want is a throttle sticking open so i expect them to be working to a very big safety factor in this area.

Hopefully your turbo air charge will never exceed say 60 deg so you should be well within the temp limits of the TB design.

Chip

iTrader: (3)

I agree, and I bet most people's 20 year old cosworth ones leak slightly by now too, so Im not sure Mikes tests of "old" throttle bodies really prove a lot!

The seals are designed on a N/A TB to resist a pressure differential of as much as about 12 psi anyway as standard, and are always over engineered.

Garage19

I was once told by an automotive design engineer i was chatting to that pretty much every thing on a car is designed with a safety factor of at least 5.

Eg the suspension will take 5 times the design loads before breaking.

I expect they apply this sort of factor to any other critical parts.

RWD_cossie_wil

iTrader: (9)

For most people (including me!) 99% of the time it works out cheaper in the long run just to buy the part that is known to fit easily and work correctly, rarther than spend hours fucking about making somthing fit and work , when there is a part avaliable to bolt on in 20 mins .....

It occured to me the other day, I don't enjoy working on cars anymore, just get bored of getting dirty, cold and cut to bits . Just want to drive the fucking things

Chip

iTrader: (3)

LOL, fair enough.

Plus DIY is only cheap if your time has no value

Turbo Zetec

iTrader: (1)

doug - i thought 2.0 zetec ones were 55mm? i've never measured one personally though, have you? either way, i'll be using one for my ZT project

Garage19

Yup, 2ltr one is deffo 60mm.

What you putting the ZT in? Sierra?

Turbo Zetec

iTrader: (1)

cool, its going in this:

https://passionford.com/forum/showth...=165369&page=5

NEIL A

iTrader: (6)

This is what i have on mine think it came off a BMW.

Only problem is you need to mount the iscv in a remote housing.

col cos1

iTrader: (5)

i bought a big one off a jag but havent used it yet,my car is making the power on standard throttle

J1mbo

iTrader: (1)

its been said above but to put it into perspective is

a rs200 throttle body is smaller (cant remember exact size) than a 2wd one and can flow 750+ bhp so there is deffinately no need to change it