TR674 Posted May 25, 2015 Report Share Posted May 25, 2015 Hello o'wise ones, I have installed new blue poly throttle rod bushings (3 off) over the weekend, the old yellow ones were hardening and crumbling. Now my inlet manifolds are not quite synchronised. Front 2 butterflies are opening late. However I have adjusted them by eye to open all together as close as eyeballing can go (huge improvement in slow speeds-surging greatly reduced). Is there a more accurate way to do this than eyeballing? Quote Link to post Share on other sites
grumpy2 Posted May 25, 2015 Report Share Posted May 25, 2015 If I understund you correctly then I had a similar problem with mine. Butterflies opening at slightly different times and poor light throttle running. I bought one of these.... http://www.pentastarparts.com.au/store/index.php?l=product_detail&p=4654 And used it to get the same airflow through each throttle body at 1500rpm. Made an amazing difference to the drivability of the car. Easy to adjust by slowly turning the butterfly connector rods, they have a locknut and slotted head so are meant to be adjustable. Took less than half an hour Gary Quote Link to post Share on other sites
john.r.davies Posted May 25, 2015 Report Share Posted May 25, 2015 No argument with grumpy, useful tool! But you probably have a feeler gauge already, and most go down to 1.5 thou,which feels like tough kitchen foil. Slide that between the butterfly and the throttle inlet wall, and adjust, until the 'feel' of pulling out the leaf is the same all across the head. Done! Old timers used to use a cigarette rolling paper, with about half that thickness, but then they could only adjust to a very light 'grab' on the paper, so not much difference. John Quote Link to post Share on other sites
TR674 Posted May 25, 2015 Author Report Share Posted May 25, 2015 (edited) Grumpy, that looks like a handy tool. John, the feeler guage is good for setting the butterflies at idle, but I'm trying to get them all opening at the same time, by the same amount. Edited May 25, 2015 by TR674 Quote Link to post Share on other sites
modelbuilder Posted May 25, 2015 Report Share Posted May 25, 2015 I have used one of these for years and find it easy to use and fit for purpose. http://www.ebay.co.uk/itm/SU-Twin-Carb-AIR-FLOW-METER-JET-SPANNERS-for-MG-1100-1098cc-1962-68-/390927724986?pt=LH_DefaultDomain_3&hash=item5b051bb1ba Rodders. Quote Link to post Share on other sites
john.r.davies Posted May 25, 2015 Report Share Posted May 25, 2015 Persevere with the ciggy paper/feeler, '74! It will set directly the amount the b'fly is closed, at idle. That is a function of the adjuster on the left end of each butterfly bar. AND it will tell you when the B'fly begins to open. That is a function of the linkage between the centre and fore and aft throttle bodies, and the Triumph TR6 manual recommends the use of a feeler gauge. (129.20.05 Sheet 6) The amount each opens for the same throttle setting is a function of the lever mechanism, and that's not adjustable. Those flow measuring devices are a useful check, but the function of each part of the system needs to be understood. John Quote Link to post Share on other sites
Andrew Smith Posted May 25, 2015 Report Share Posted May 25, 2015 I've bought one of these on eBay: a Crypton Synchro Check Tool as used in the' brown bible' - that way, I can use the recommended air-flow measures at the stated RPM. Haven't used it yet mind................. Cheers Andrew Quote Link to post Share on other sites
astontr6 Posted May 25, 2015 Report Share Posted May 25, 2015 Dear All, +1 I have used the Cryton Synchro Check for years, cannot be faulted ! I have found that the best RPM to set the balance at 1500 and then to recheck at 2000 RPM. As this is a very precise tool you may have difficulty in getting the balance right at tick over, due to wear on the butter- fly spindles or slackness in the linkage take up! If this is the case, zero the balance exactly at 1500 to 2000 RPM. Lastly this best done with 2 people. Bruce Quote Link to post Share on other sites
Andy Moltu Posted May 25, 2015 Report Share Posted May 25, 2015 Use the throttle cable to set tick over at 1500 to 2000 with the air screw closed and balance with carbalancer or cryptocheck as above Quote Link to post Share on other sites
TR674 Posted May 26, 2015 Author Report Share Posted May 26, 2015 Thanks gents, I will source the Cryton Synchro. Thanks John, with 40+ years of wear, each component of the throttle mechanism has lots of play, so it's gatting harder to set each throttle body to mach the next. I can get it reasonably close but still some surging at low speeds which is annoying................I shall perserver!! Quote Link to post Share on other sites
Guest ntc Posted May 26, 2015 Report Share Posted May 26, 2015 You can get new rose jointed rods that will sort you out. Quote Link to post Share on other sites
ShaunC Posted May 29, 2015 Report Share Posted May 29, 2015 http://www.tr-register.co.uk/forums/index.php?/topic/51597-cp-throttle-bodies/?view=findpost&p=422599 Quote Link to post Share on other sites
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