306 Xsi 8v - How Big Is The Throttle Body?

[Arahan 4]

Anybody know how big the standard throttle body is on a 306 xsi 8v?

 

And if any bigger ones would fit? Thanks!

 

- James

[Arahan 4]

Nobody know?

[welshpug 1,668]

if I remember tomorrow and happen to call into a scrapyard I'll measure one, did see an 8v 2.0 405 there earlier today.

[Arahan 4]

Do they share the same throttle body? What about the inlet manifold, is that the same too?

 

I hope you do remember! ha!

 

Thanks alot welshpug!

[zebedy101 0]

You could try pm atari boy, he runs a 2.0 8v lump in his 205 I'm sure he would be happy to help.

[Arahan 4]

Good thinking batman, il give him a PM! Thanks!

[jengis 0]

60 mm i/d

 

or therabouts, measured with a tape, not a steel rule so can't be that accurate. I have the mani in my shed, don't need it by the way, if its any use to anybody...

 

Kev

Edited January 16, 2010 by jengis

[Arahan 4]

The inlet mani and throttle body? I may take that off your hands...PM me!

[Henry Yorke 269 3 Cars]

I know the 8v turbo one was only 50mm compared to the GTIs 57mm one. If the XSI one is bigger then it would be an upgrade for a standard GTI.

[jengis 0]

I know the 8v turbo one was only 50mm compared to the GTIs 57mm one. If the XSI one is bigger then it would be an upgrade for a standard GTI.

 

 

Yes, notably larger than GTi. But it's a completely different manifold set-up so not swappable.

[Arahan 4]

But the inlet mani and ports are the same as the 2.0 8v turbo arent they? I was thinking about swapping the 8v turbo manifold for this one as it looks to flow better, and has a throttle body thats apparently 10mm bigger.

[Atari Boy 11]

Sorry, only just seen this, I am running standard 1.9 inlet manifold etc. so I can't be much help.

I have a spare XU10J2 head if that helps though.

[Henry Yorke 269 3 Cars]

But the inlet mani and ports are the same as the 2.0 8v turbo arent they? I was thinking about swapping the 8v turbo manifold for this one as it looks to flow better, and has a throttle body thats apparently 10mm bigger.

Sounds logical if it is bigger, though if it was that easy I would have thought this would be the first mod everyone would make. I think the ECU would be able to adjust to cope as mine seems to have as I am running an XU9 inlet and throttle body on it (though my head is also XU9). I think the benefit for me is in the GTI plenum chamber and the throttle body dimensions which is why I have got 164 bhp out of a 1905 with no other mods.

[Arahan 4]

Its been touched on but i think people dont really go for mods like this, as its a turbo engine they just automatically think bigger changes, turbo, intercooler, more boost etc rather than these little overlooked changes! Going to give it a bash and report on how i get on and if theres any benefits! Little concerned about heat soak though as its plastic, sure I could counter it with something though.

[cammson 0]

Right can someone clear this up for me...

 

i am currently running a 1.9 gti lump but i have a complete 2.0 8v 306 xsi lump, is it possible to swop the TB and Inlet Mani onto the 1.9 head?

or can i just bolt the 2.0 head and all its bits straight onto my 1.9 gti engine... getting a bit confused with all this lol... and would it be worth doing any of this? lol

 

cheers.

[Arahan 4]

Not much point really swapping onto a 1.9 gti, im after this info for the 2.0 8v turbo engines XU10J2CTE as they have a small throttle body and not the best inlet manifold.

[Henry Yorke 269 3 Cars]

Right can someone clear this up for me...

 

i am currently running a 1.9 gti lump but i have a complete 2.0 8v 306 xsi lump, is it possible to swop the TB and Inlet Mani onto the 1.9 head?

or can i just bolt the 2.0 head and all its bits straight onto my 1.9 gti engine... getting a bit confused with all this lol... and would it be worth doing any of this? lol

 

cheers.

The head needs a good skim to get the compression down to standard. This means you can end up with your timing slightly out, so really need a vernier to compensate. You will get bigger valves in your head then. Technically the inlet and TB will then fit too however I am not sure the TB switch is wired the same so you may need some adjustment. I think the cam is a bit lame compared to the GTI one but am not 100% sure.

 

Is it worth it? Probably if you need your headgasket and valve stem seals doing. Otherwise you will not get any huge gains from this conversion without other mods. 28Craig and I think Anthony have done this conversion before

[Silky 33 1 Cars]

I have a spare 8v XSI engine and a 1.9 GTI engine in my garage, it was something I was going to play about with in the summer

[Arahan 4]

Got the inlet and throttle body now so going to give this a bash shorty!

 

Does the 8v turbo fuel rail fit this manifold does anyone know? Or should i have been sensible and got the 8v xsi fuel rail?