42mm ID Throttle Body/Trumpet Spacers

[Willie.]

Hi all,

 

I believe QED sell spacers for 42mm Jenveys, which are more or less just a block of solid ali with three holes in it, used to space the trumpet out from the TB. I can't find these on their website; just the tapered 42-45mm ones.

 

I was looking at some tonight on a friend's car, his are 25mm long. Does anyone know if they're available from QED, or anywhere, in different lengths?

[Willie.]

Answered my own question; available from Jenvey here

 

Not cheap though...

 

Does anyone have the dimensions for the face of a DTH 42mm Jenvey TB? i.e. the relationship of the 3 holes to make spacers? Jenvey used to have drawings on their site, but I can't see them anymore.

[rj]

Willie

 

 

I'd expect them to be simialr to the 45mm bar the drilling, in which case I can look into it for you.

 

I am a lazy boy and hence do not feel like stripping my car to measure the 42mm's

 

/r

[Rob Walker]

The QED spacers have a machined taper through them 42 opening out to 45. It is not just a simple parallel hole which accounts for the price.

 

Rob

[Willie.]

Hi Rob, appreciate that, but I've found that the Jenvey parallel spacers, bored whatever ID to suit, at 25mm deep are £27+ Vat each. I'd need 8 to get my required depth, so that works out horrendously expensive.

 

Hi Regin , I didn't want to impose on your genorosity too much, but if you're happy to measure the 45s, that would help massively. I should be able to get my hands on a suitable billet of ali, so just need the dimensions to mill them out accurately.

 

My mate's 45 trumpets, 45-42 taper spacer and 42 spacer all fit the same retaining bolts, so I agree, the 45mm ID and 42mm ID will use the same spacer, just different bore.

 

Time to fire up the Bridgeport.

[Jason Plato]

you take the dimension for the center holes of the two bolts from your throttle bodies and then obviously the taper from 42mm - 45mm will need to be calculated depending on the thickness of the spacer.

 

I did a differnt approach and made some 30mm thick 42mm ID spacers with parallel bore and put these on the throttle bodies and then also bolted the tapered QED items on the end to open up to mate to the trumpets .

[Willie.]

Dave, that's exactly what I want to do, although I was just going to run with 42mm Trumpets too (i.e. no tapered spacer to go to 45).

 

Reason for the spacer is just to let the backplate clear the fuel rail etc.

 

By any chance do you still have the dimensions for making your 30mm spacers? This is for a car I'm buying in England, and I want to swap the air box for a filter before getting it mapped at Emerald on the way home. I'm hoping to get the spacers made over Christmas and take a filter with me and fit it when I lift the car.

 

 

[Jason Plato]

I don't have the dimensions as I now have a duratec with 45mm tottel doddies

[Mankee]

I've only just skimmed the thread, so I might have missed some details. Are you using the Jenvey fuel rail on some K-series 42mm DTH bodies? If so, I had the same problem with getting a back plate to clear the fuel rail. I got a local metal-working guy to make me a custom deep-dish back plate in the end.

 

The Jenvey site does still have a drawing that might be useful to you:

 

http://www.jenvey.co.uk/home/accessories/airhorns-filters-and-boxes/jenvey-dynamics/air-horn-42mm-x-100-carbon-ahc42x100/pdf-drawing

 

Or you can try Emerald's ALI kit with a pair of extra adaptors flipped over so that you can mount a flat back plate filter:

 

http://www.emeraldm3d.com/throttle-body-kits/emerald-adjustable-length-intake.html

[Willie.]

Thanks Mankee, that drawing is exactly what I'm after.

 

I've also just had a mate drop in with me and told me that I still have a big billet of ali sitting in his workshop, so looks like I'm in business.

 

Not sure what fuel rail it is, but fairly certain I'll need spacers to clear it, and I'd like the additional length on the inlet also.

 

On Emerald's site the adjustables are only available in 45mm. I'm guessing, but I suspect with the 42mm TBs, any reduction in ID is better avoided.

 

Thanks all for the help.

[Mankee]

Emerald's website hasn't been updated, but the ALIs are available in 42mm for definite, as I have some. Seeing as you are having your car mapped there, I would certainly consider getting a set of their adjustable trumpets and having a fiddle about with the lengths to get the sort of curve that you are after. A highly useful bit of kit!

[Willie.]

Thanks, assumed they weren't available in the smaller ID, so good to know they are. Will be fairly tight for time, but might give them a try if time permits or curve isn't looking good (Not that I'd know a good one).

 

I think from reading in the archives that you run a big C604D Pipercross filter? May I ask what length of trumpets you're running and where you have your backplate mounted?

[Mankee]

I can't remember the exact length I've set the trumpets to (and it's smashing it down with rain outside now!), but they were for my previous engine and I guesstimated a length that I randomly picked after removing the 100mm carbon trumpets I had on before. Strangely enough, a 5mm change in length in either direction gave unsatisfactory results at Emerald earlier in the year. 130mm trumpet length seems to ring a bell though.

 

My backplate is mounted directly onto the bodies. I tried Jenvey/Pipercross backplates, both flat and 50mm stepped, and neither of them fitted, as they fouled the Jenvey fuel rail or a chassis rail. Again, I can't remember the depth of the offset off-hand, but it's more than 50mm. That as well as a C604D Pipercross filter means loads of room for the trumpets to breathe. Only provisos are that I have to fit the filter upside down and I've cut a wedge out of my bonnet. I'm not too worried about appearances though as my car is a track-only shed. I could probably have gotten one of the smaller filters to fit it all under the bonnet, but the filter was a bargain and I didn't mind having a hole in the bonnet.

 

Some pictures might help explain a few things:

 

http://images56.fotki.com/v371/photos/8/42688/7812053/DSCF1774-vi.jpg

 

http://images107.fotki.com/v67/photos/8/42688/10523039/photo1-vi.jpg

 

PS. Shame to see that your V6 project wasn't finished. That would have been a beast!

[Willie.]

Thanks for the pics and info. I'm hoping to take 90mm trumpets with me and the spacers will be about 45mm, so with the backplate added in, it's probably going to be about 137mm from face of TB. I'll also have the 50mm trumpets from the airbox there to try if necessary.

 

Is Dave usually happy to fit the adjustables for to find the right length/mapping, and then remove? Or would he only really allow them to be used if the intention is to purchase? Budget is being blown by the car purchase, and trying not to rack up another small fortune before even getting home!

 

Your setup with the backplate looks nice. I'd be tempted to do that, as I do like the idea of having plenty of air around the trumpets. Internal height of the 604D is 125mm, so I think with the 90mm trumpet giving 35mm to inside face of filter, it should be ok.

 

I actually really like the look of a filter sitting out through the bonnet. The only reason I'm trying to avoid it is because I don't want to have to start into filing at a bonnet in a panic at Dave's. I can make a deeper backplate and do that when I get home if necessary.

 

Thanks for comment on V6. I'm gutted that I ran out of money & time, but life moves on and I just wasn't able to complete it. We're house buying, and it's going to require alot of money & time to fix up. I decided it was better to abandon, sell up and try and get myself back in a working 7...and I can do another project when time & funds allow. It wouldn't be everyone's taste, but I'd sure love a 3ltr V6 monster Caterham. Hanging the tail in 5th with the V6 soundtrack would be serious fun.

[Jason Plato]

drive home without a bonnet

[Mankee]

It might be worth a phone call to Emerald to let them know your intentions and see what Dave thinks. For the cost and simplicity of a set of adjustable trumpets and an extra pair of brackets to mount the back plate, it might be a better way of doing this?

 

It will save on you having to make up spacers when back at home, might save a few grammes in weight, means you can get everything set up in Watton there and then, and, if you do decide to upgrade in the future, you can tweak the inlet length to suit.

 

When are you planning on picking up the car and making the trip over? I normally make an annual journey with my car to see them each January for a checkup, but next January is going to be particularly busy for me. ☹️

[Willie.]

Hopefully mid to late January. Can't wait for the run home. After Emerald we will be heading for Stranraer for the boat; won't have alot of time, but if there are any decent roads en-route anyone could suggest, I wouln't mind taking one or two in.