GordonW Posted July 27, 2011 Share Posted July 27, 2011 I'm considering the QED DTH bodies as among all the other well discussed reasons they do away with the restrictive manifold but I'm wondering since these TB's are straight do they need a curved adapter/spacer to get them to anything like the right position (ie manifold substitute) for a filter to stick out of the bonnet .....can the community wisdom advise of this and any other installation issues to be prepared for please particularly choice of filter/backplate or airbox? Link to comment Share on other sites More sharing options...
oilyhands Posted July 27, 2011 Share Posted July 27, 2011 some time ago Dave Walker did some back to back tests with a curved inlet manifold and TBs against the straight DTH TBs, the TBs with the curved manifold made more power and torque as I recall. It might be worth trying to get a copy of the article to see whether it throws more light on the subject. Oily Link to comment Share on other sites More sharing options...
GordonW Posted July 27, 2011 Author Share Posted July 27, 2011 Dunce that I am I suddenly realised that the mounting flange on the head is already at an angle of about 25 degrees so I guess that this sends the bodies off to something like the right spot? Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 27, 2011 Share Posted July 27, 2011 If you (or anyone else who'd like a copy) blatmail me your email address I can send you a copy of the CCC article that Oily refers to as I scanned it some years ago. If you have the standard Vx carburettor bonnet cutout you'll have to modify the hole whatever TBs/filter arrangement you have as the standard chokes are horizontal by virtue of the curved manifold and the sausage filters are a lot larger than the original KNs. The DTHTBs will be at the head inlet flange angle which will result in a bonnet hole, similar to other 'straight shot' induction systems, e.g. SBD tapered throttles. One thing to bear in mind is the length of inlet tract required for mid range performance. As you will see from the article, air trumpet length has a significant effect on the revs at which peak torque occurs, as you would expect. The lack of manifold length will mean you will need to increase the length of the trumpets to compensate. Paul Link to comment Share on other sites More sharing options...
Mankee Posted July 27, 2011 Share Posted July 27, 2011 Paul, I'll drop you a line in a moment to get a copy of that article, as it sounds interesting and I don't think I've seen it before. As you say, induction/inlet tract length is very important and has a major effect on the shape of the curves. Emerald/Dave Walker have a new product coming out soon to make changing induction lengths easier, but I'm not sure if it's all public knowledge just yet. Link to comment Share on other sites More sharing options...
Lee Fowler Posted July 27, 2011 Share Posted July 27, 2011 Hi Paul can you sort me out a copy, please? Lee Link to comment Share on other sites More sharing options...
Area Representative gileshudson Posted July 27, 2011 Area Representative Share Posted July 27, 2011 Can I get a copy too please Paul? You have a BM with email address. Cheers, Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 27, 2011 Share Posted July 27, 2011 article posted to all requests so far. Paul Link to comment Share on other sites More sharing options...
alan c Posted July 27, 2011 Share Posted July 27, 2011 Paul And me as well please. How is the rebuild going? Regards Alan Link to comment Share on other sites More sharing options...
oilyhands Posted July 27, 2011 Share Posted July 27, 2011 Top marks Paul for distributing the article which would have taken days for me to find. Oily Link to comment Share on other sites More sharing options...
Paul McKenzie Posted July 27, 2011 Share Posted July 27, 2011 Not got mine yet ☹️ Paul Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 27, 2011 Share Posted July 27, 2011 Hi Paul That's odd. Anyway I've just sent it again so you should get it now. If anyone else is having problems let me know and I'll have another go. Paul Link to comment Share on other sites More sharing options...
Paul McKenzie Posted July 27, 2011 Share Posted July 27, 2011 Still no luck ☹️ Link to comment Share on other sites More sharing options...
Mankee Posted July 27, 2011 Share Posted July 27, 2011 I hope that Paul (Deslandes) doesn't mind, but I've uploaded the article to my webspace so that you (and anyone else) can download it. It's located here. Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 27, 2011 Share Posted July 27, 2011 Thanks Mankee, I was hoping someone might offer to do that. I've sent it twice now Paul so I wonder if its going into your spam folder. I've sent it as a reply to your email so there shouldn't be any typos in the address. Link to comment Share on other sites More sharing options...
Paul McKenzie Posted July 27, 2011 Share Posted July 27, 2011 Well, still didn't get it... but if you sent it as a reply to my Blatmail I didn't think that allowed attachments. Anyway, no problem, I'll get it from Mankee's site. Thanks guys Paul Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 27, 2011 Share Posted July 27, 2011 that really is very odd. I've replied to a number of others who seem to have received it ok. I replied to your email address so it shouldn't matter about blatchat rules re attachments. I can only assume your ISP doesn't like my email address for some reason. Anyway, so long as you can download it from Mankee's site you'll get it ok. Link to comment Share on other sites More sharing options...
GordonW Posted July 27, 2011 Author Share Posted July 27, 2011 Thanks Paul and Mankee, a useful read. Link to comment Share on other sites More sharing options...
Chris Cardwell Posted July 27, 2011 Share Posted July 27, 2011 Many thanks for the article, really useful, wanting to convert to fuel injection soon. Link to comment Share on other sites More sharing options...
Lee Fowler Posted July 27, 2011 Share Posted July 27, 2011 Thanks Paul. Lee Link to comment Share on other sites More sharing options...
k.russell Posted July 27, 2011 Share Posted July 27, 2011 had the QED dth bodies on my seven for a good few years now here is a picture to give an idea of the length angle etc. Edited by - k.russell on 27 Jul 2011 20:35:14 Link to comment Share on other sites More sharing options...
k.russell Posted July 27, 2011 Share Posted July 27, 2011 a link to the album with a few more pics here Link to comment Share on other sites More sharing options...
GordonW Posted July 28, 2011 Author Share Posted July 28, 2011 Thanks all, Kevin great reference pictures thank you just the job and lots of evidence of your engineering skills. Link to comment Share on other sites More sharing options...
GordonW Posted July 29, 2011 Author Share Posted July 29, 2011 Kevin, is that a basically a Jenvey OT linkage with your own mods that you are using? Link to comment Share on other sites More sharing options...
keybaud Posted July 29, 2011 Share Posted July 29, 2011 Not meaning to hijack the thread, but there's no point starting a new one when this one has some really useful links in already. I'm looking at the benefits of changing from Weber 48s to fuel injection on my VX engine and I'd be grateful for any comments or observations on the pros and cons of doing so. I emailed Northampton Motors for their recommendations, as they did the work on the engine for the previous owner, and Troy mentioned the OMEX kit as a cost effective option (cost effective being a subjective term when there's a a number of extra costs involved when converting from carbs to injection). Thanks, Simon Link to comment Share on other sites More sharing options...
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