Throttle body disc valves, where can you buy them?

[Boosted LS1]

Hi, rather then reinvent the wheel I'm trying to find a source of 50mm disc valves. Google isn't being very helpful. There must be a company in the UK churning out volume numbers for the likes of Jenvey and carb manufacturers. Anybody got an idea? Thanks.

[Classic Grad 98]

Never heard them referred to as 'disc valves', try searching for 'butterfly' valves instead.
P.S. it's not a very universal part really as they tend to be integral to the manufacturer's own throttle body- can't you modify an existing throttle body?

[Pumaracing]

Webcon UK will sell them to you.

http://www.webcon.co.uk/shop/shopdisplayproducts.a...

Outrageous price though. £9.95 each to the trade and £12.44 retail.

Might be worth contacting Jenvey as they no doubt make their own given those prices. A couple of quid each would be about right given how simple they are to make.

[Boosted LS1]

Thanks for the replies.

Puma, I'd seen their prices to! It seems that some may have a champhered edge and sit in the choke at between 5 or 12 degrees depending on which butterfly you look at. Would this be to prevent sticking?

I'll try Jenvey and see if they have anything suitable. If not I'll have to get them made.

[DVandrews]

You need the angled edge for it to seal against the TB choke area correctly, the shut angle will materially affect the initial throttle response, the smaller the shut angle the more progressive the initial throttle opening will normally be. The shut angle will also differ depending on whether the TB is supposed to run at idle nearly completely closed (idle air via IACV) or partly open to sustain idle.

Pretty sure Jenveys are 8 degree. Bike carbs and TBs tend to have higher shut angles.

You can improve (increase) throttle response from closed throttle by tapering the lower edge of each side of the throttle plate.

Some TBs have a partial hemisphere (wedge) attached to the lower half of the throttle plate to soften throttle response and avoid kangarooing, this ensures that very little air passes through the lower half of the TB until throttle opening reaches around 20 degrees.

Dave

Edited by DVandrews on Tuesday 31st January 17:56

[Boosted LS1]

^^^^

That's interesting, thank you. A similar product uses 14 degrees iirc. This is ls7 stuff. Jenvey are being helpful and are sending me a sample. Tiz a small world, I fould out they have one of my manifolds on a turbo car