Yep I understand AM did actually build a Vantage S with twin throttles but scrapped the idea on a cost basis.
My 5.0 GT4 engine will have twin throttles

 

Nope only fitted to the S

 

Like the 3 factory drives who hydrolocked new vanquishes not so long ago

 

you're the second person i've seen mention a GT4 this week. what is that?

huh, that's odd. seems like an easy way to bump up the power across the V8 range. and if they're limiting themselves to 420-430 hp on purpose to leave room for easy "now with more power!" bullsh!t later, that's just annoying...

 

I though the GT4 was the street / track model. Limited run of cars and a factory race car option.

 

Might have been me the other time, the GT4 race cars have a hand built and tuned version of the 4.7 engine, many supplied by Bamford Rose in the UK.
They are using my car to develop a 5.0 version, though mine will have a few extras that the race cars are not allowed (twin throttles, ceramic coated headers, different cams)

The N400 intakes only went on the N400 and the S, they didn't even put them on the N420's!
The S was prototyped with twin throttles and the N400 intake to give ~470 BHP. But as you guessed cost, leaving room for the "now with more power" and not getting too close to the V12 meant it never made production

 

Huh, must be two different GT4's then, because the other one I heard referenced was definitely not an AM. I want to say it was some kind of kit car.

It's a shame AM doesn't have the confidence to really push themselves. The only real criticism of AM is their power is always down compared to their competitors. I think biting the bullet on cost, while upping the price a touch to cover the cost of the improved intake systems, would definitely pay off by bringing in more performance-oriented customers.

 

See http://en.wikipedia.org/wiki/GT4_European_Cup

 

Ah ha, I bet you're right. Thanks!

 

Does anyone know a site like Real OEM that can give mechanical break down of the V8 vantage and list parts?

I like looking at the car break down to see where I can see restrictions due to regulations.

 

https://www.astonmartintechinfo.com/...asterIndex.asp

what kind of regulations?

 

ah perfect thank you.

intake, and exhaust. I know we have been chatting about these but I wanted to see what factory design was VS aftermarket ones.

 

Forgive my ignorance but isnt the flap meant for emissions purposes. Very similiar the the BMW 3 litre diesel swirl flaps ( that many owners have taken off since they come loose and lodge themselves in the engine ). I removed mine on my 730 d, 6 small ones in total and the increased airflow was noticable in performance.

So why not remove this flap and let the emissions flow properly

 

the butterfly valve (the flap) controls airflow into the engine. when you press the throttle pedal (the gas pedal), it sends a signal to this flap to open. in conjunction with the extra air now coming through the throttle body, more fuel is added to maintain a proper AFR. removing the butterfly valve would cause massive problems for a petrol engine.

swirl flaps and butterfly valves are two different things. swirl flaps are on diesels only.

http://en.wikipedia.org/wiki/Swirl_flaphttp://en.wikipedia.org/wiki/Throttl...#Throttle_body

 

Ahhhhh. I see now.

Shame that there isnt a butterfly valve that is bigger off the parts bin from Ford or Jag but then I guess the outake pipe would be the next restriction.

If that pivot bar in the middle of the flap was say 75% smaller - wouldn't it be safe to say that airflow would increase by say at least 15%. This would improve performance when you put your foot down since the flap is on full opening. Have I stumbled on a new potential mod !!!!