AJ2014 Posted October 21, 2017 Report Share Posted October 21, 2017 (edited) Hi all, Can anybody give me some advice please.... When I bought my 1955 UK TR2 it came with an upgraded engine as the original had died way back when. The owner back then, (an employee of Standard Triumph) had obtained a brand new engine from the factory - 2138cc stamped CT10E. This owner has told me that the engine he bought was 1 of 10 bound for the U.S.. This new engine is fitted with: CD175 Strombergs Inlet Manifold - Stanpart 305744 Exhaust Manifold - 304164 Cylinder Head - High Port Struggling to read the number (see photos), two valve spring per valve. So...I would like to convert from Stromberg to SU's. I have a pair of H6 carbs on Inlet Manifold 305547 which need a refurb. Questions... Would these be a straight swap or do i need a different manifold combo to get the best out of them? What air cleaners do I need as they are missing? Will my existing throttle linkage work with the SU's (the long rod)? Any other things I need to consider in the swap? Regards Ade PS I will put some photos up to help http://s463.photobucket.com/user/apj2007/library/TR2%20Cylinder%20Head Edited October 21, 2017 by AJ2014 Quote Link to post Share on other sites
Lebro Posted October 21, 2017 Report Share Posted October 21, 2017 The inlet manifold is TR4A (the best sort), the exhaust manifold TR3/4. (single down pipe) engine is TR4/4A The best SU carbs to fit your manifold would be HS6 the TR shop usually has brand new ones on sale for a fair bit less than H6 Of course a TR2 would normally have 1991CC's a low port head, & 1¼" H4 carbs, but they won't fit your manifold. Hope this helps Bob. Quote Link to post Share on other sites
AJ2014 Posted October 21, 2017 Author Report Share Posted October 21, 2017 Hi Bob Thanks for your response. Just to clarify, is your suggestion to buy new HS6 carbs and combine them with the inlet manifold currently fitted to the Strombergs and the existing exhaust manifold? Would this arrangement have enough clearance to the inner wing with air cleaners fitted? What air cleaners would I fit to HS6? I don't want the large single TR4 type.. I have a new tourist trophy exhaust system to pair with the exhaust manifold. I obviously intend to keep the bigger capacity engine rather than going back to stock, it's a nice upgrade. Regards Ade Quote Link to post Share on other sites
ianc Posted October 21, 2017 Report Share Posted October 21, 2017 I have the TR4A inlet manifold, HS6s and K&N circular air cleaners on my TR4. There is very little clearance between the bottom of the forward air cleaner and the inner wing - about the width of my finger. The TR4 is wider than the TR2/3, so I think you would need to use air cleaners of a different shape, or get a skilled person to reshape the inner wing to accommodate the forward air cleaner. The HS6 is superior to the H6 in its arrangement for feeding fuel from the float chamber to the jet - it uses a tube, so it doesn't relieve itself of expensive fuel all over your hot exhaust manifold. Ian Cornish Quote Link to post Share on other sites
Hamish Posted October 21, 2017 Report Share Posted October 21, 2017 This is my set up on a 3a. Its the original H6 carbs. A bit longer than the HS6 I believe. They are short stubby stacks with a mesh on. The front ones graze the inner wing on full engine mounting rock. Quote Link to post Share on other sites
Drewmotty Posted October 21, 2017 Report Share Posted October 21, 2017 I have the 4a long manifold and HS6 carbs on my TR3 together with K&N cone shaped filters. There is plenty of clearance. Quote Link to post Share on other sites
Lebro Posted October 21, 2017 Report Share Posted October 21, 2017 (edited) This is my setup in my '56 TR3 Bob Edited October 21, 2017 by Lebro Quote Link to post Share on other sites
Ian Vincent Posted October 22, 2017 Report Share Posted October 22, 2017 I have something very similar to Bob on my 3a, it works well. With the HS6 carbs you will need to do something about the heater connection at the bulkhead where it clashes with the float chamber of the rearmost carb. I fabricated a special bulkhead connector with a tight bend but the alternative is to use a TR4 connector on the nearside bulkhead. Rgds Ian Quote Link to post Share on other sites
Lebro Posted October 22, 2017 Report Share Posted October 22, 2017 Like this: Bob Quote Link to post Share on other sites
AJ2014 Posted August 11, 2019 Author Report Share Posted August 11, 2019 All, Thanks to all for your tips and replies...I know it's a while ago. I have now purchased a pair of HS6 carbs to go with my TR4a inlet manifold. Cheers Ade Quote Link to post Share on other sites
BlueTR3A-5EKT Posted August 11, 2019 Report Share Posted August 11, 2019 On 10/21/2017 at 4:56 PM, Lebro said: The inlet manifold is TR4A (the best sort), the exhaust manifold TR3/4. (single down pipe) engine is TR4/4A The best SU carbs to fit your manifold would be HS6 the TR shop usually has brand new ones on sale for a fair bit less than H6 Of course a TR2 would normally have 1991CC's a low port head, & 1¼" H4 carbs, but they won't fit your manifold. Hope this helps Bob. Ah, but SU HS4 or their equiv later HIF (ex MGB) will come close as the flange is diagonal mounted. So will be able to fit the TR4A inlet manifold using a simple adaptor plate. Someone on here did this a while back and I have a photo of the installation somewhere. HIF (?Horizontal Integral Float?) has an integral float chamber, not the pot hanging on the side. Alternatively use HIF44 ( HS6 replacements) then the flaot chamber is not touching the bulkhead heater adaptor. The Mini boys have these to make it all scream a bit louder. You will need the linkage from HS6 with TR4A inlet manifold or make up a cable kit as we did in the past. I have the installation instructions 'wot we rit' somewhere. Below is a shot of how I did it in 1975 and is still working today. Cheers Peter W Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.