Throttle body options - 420R

[aerobod - near CYYC]

17 minutes ago, graearea said:

I've only been black flagged at bedford. if you don't pin it past the noise meter you're fine.

Do you have any additional exhaust silencing, besides the standard Caterham side exhaust? Do you think you would be black flagged at Bedford for intake noise alone?

I’m trying to determine if my local track (Rocky Mountain Motorsport) near Calgary will black flag me once I have the car out there with the new throttle body installation and external filter, due to induction noise. I already have to run a SuperTrapp system on the exhaust to keep below their noise limits, although I plan to add 6 more disks to the existing 18 to increase my exhaust flow somewhat.

[graearea]

I've got a RaceCo Ti exhaust in the hope of keeping the noise down. not sure how much good it does. I do have an exhaust bung but haven't used it.

[Doc007]

On 28/02/2024 at 20:40, JAL73 said:

 

As its a non-trivial amount of money I'd love to experience Jenveys before I buy. So if anyone in Surrey/ London area would offer a demo I''d be eternally grateful. 
 

I’m happy to take you for a spin in my car if you like. I’m in Surbiton. My car is going for some fettling to PGM but will hopefully be back on-line within the next couple of weeks. Drop me a line if you’re interested.

 

[Doc007]

A friend of mine has a 200bhp Sigma with Jenvey throttle bodies. His car sounds amazing especially through the intercom when we drive together. And whilst my Cosworth throttle bodies on my Duratec sound a lot better than the plenum did his knocks mine into a cocked hat.

Do Sigmas on TBs sound better than Duratecs? Or is it more a function of Jenvey Vs. Cosworth TBs?

 

Edited March 2 by Doc007

[Ainsley]

The noise coming out must be affected by the revs as well as the TB's. All sorts of things impact the sound.  I would imagine the actual body will be a similar size and length, so perhaps that not going to have an affect on the sound.  Same trumpet shape, same sound caused by them, but the head, engine, revs will be different.

[JAL73]

5 hours ago, Doc007 said:

 

👍Cheers! Will send over a message now

[BigCol]

On 29/02/2024 at 18:59, Ainsley said:

*Orders Throttle Body conversion kit and starts cutting a hole in the bonnet*

Impressed that having just started your kit, you have contracted upgraditus already! 

[Shaun_E]

On 29/02/2024 at 12:00, Drakman said:

Can someone please let me know the part numbers for ITB mounted fuel injectors and fuel rail for use with the flat back air filter.  I'm guessing either 250cc or 330cc injectors.

Take a look here: https://www.jenvey.co.uk/throttle-bodies-and-components/fuel-injectors

I have the Siemens 630cc/min which are not ideal as they flow way too much. They fit using the Jenvey fuel rail and come with a small spacer to enable that fit. I am thinking of swapping to the 440cc/min ones. I think you can probably use either of the Pico injectors as well - probably best to give Jenvey a call and they can advise. 330cc is probably fine for a stock 420 but do check. My engine is 260bhp and probably needs more flow than that but it's not an exact science!

[Drakman]

Thanks Shaun, I do have the Bosch green giants but they won't fit if i move the injectors to the ITB's.  It looks like i might need another fuel rail as well.