JP Posted August 6, 2013 Share Posted August 6, 2013 Hi All,After ordering a heatshield off ebay for my 1500 spitfire I have discovered that my carbs are from the original 1300 (HS2's) My engine is a 1500 from a Toledo fitted by the PO ( DM1466HESS (Toledo 1500 reconditioned (ESS suffix defines recon))Question I have should I be replacing my carbs for HS4's ? or will the HS2's be fine.Cheers Quote Link to comment Share on other sites More sharing options...
JP Posted August 6, 2013 Author Share Posted August 6, 2013 Looking at THIS THREAD it seems the Americans almost prefer HS2's on there 1500 !Ebay chap who I bought heatshield off has kindly offered a refund if I stick with the HS2's. Quote Link to comment Share on other sites More sharing options...
bodders1 Posted August 6, 2013 Share Posted August 6, 2013 HS2s will be fine for pootling around town. The whole lot will get a bit asthmatic when pushed into higher revs. The key difference between HS2s and HS4s is and extra 1/4 inch diameter on each of the throttles. By my rough calculations, that extra 1/4 inch equates to nearly 50% more cross-sectional area in the throttles for air to be sucked through when the engine as at full-chat.Of course, upgrading to HS4s is not suddenly going to unleash 50% more power because there are many other factors in play, such as the effect of turbulence in the carbs, the jetting, the throttle spindle getting in the way of the airflow, the type of exhaust fitted, the flow efficiency of the head itself, etc.. Quote Link to comment Share on other sites More sharing options...
Richard B Posted August 6, 2013 Share Posted August 6, 2013 As I recently found out, some of the early 1500 saloon engines came with HS2's.If you go to HS4's you may have to do other upgrades to release the potential such as; cam, compression, exhaust manifold etc... Quote Link to comment Share on other sites More sharing options...
JP Posted August 6, 2013 Author Share Posted August 6, 2013 Cheers for the response sounds like if I can get my hand on some cheap HS4's it would probably worth doing.Will the inlet manifold be the same engine side? Basically if I get some HS4's with inlet manifold attached will it bolt straight on?thanks Quote Link to comment Share on other sites More sharing options...
CHRIS211083 Posted August 6, 2013 Share Posted August 6, 2013 These would do you.http://www.ebay.co.uk/itm/TRIUMPH-SPITFIRE-MK4-1500-1-1-2-TWIN-HS4-SU-CARBS-MANIFOLD-AIRBOX-/350844806238?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item51affae45eOR these.http://www.ebay.co.uk/itm/TRIUMPH-SPITFIRE-TWIN-SU-CARBS-REMOVED-FROM-A-1975-1500cc-CAR-/350849039801?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Car+Make%3ATriumph%7CModel%3ASpitfire&hash=item51b03b7db9Or These:http://www.ebay.co.uk/itm/Twin-SU-HS4-Carburettors-Carburetors-Carbs-Manifold-Spitfire-Triumph-Midget-1500-/330970764343?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Car+Make%3ATriumph%7CModel%3ASpitfire&hash=item4d0f651437However they will all have there own problems and will probably need rebuilding and then before you know it you could have bought THIS COMPLETE KIT!!!!!!!!!!http://www.ebay.co.uk/itm/TRIUMPH-SPITFIRE-67-80-WEBER-CARBURETOR-CONVERSION-NEW-/281142104099?pt=Motors_Car_Truck_Parts_Accessories&hash=item4175601023£200 +shipping. Modern style carb so much better for tuning etc do better mpg etc. I would stop here and buy one of these as it will save you cash in the long run. However if you want more than this carb can give then look AT SWAPPING THE ENGINE. Just my opinion.Chris. Quote Link to comment Share on other sites More sharing options...
CHRIS211083 Posted August 6, 2013 Share Posted August 6, 2013 You could also spend all day asking how to get your fueling correct with hs2-4's and never get it right. Where the modern webber has instructions and has enough points of adjustment to give you the correct fueling. I spent a long time trying to get the hs2-4's spot on and came up with the conclusion that they never will be and are just old tech. Just my opinion.Chris. Quote Link to comment Share on other sites More sharing options...
CHRIS211083 Posted August 6, 2013 Share Posted August 6, 2013 JP I've had a great idea. Buy the webber kit above. Then if you want more you could easily convert your car(using that manifold) to efi. It would be very easy and also future proof.Chris. Quote Link to comment Share on other sites More sharing options...
npanne Posted August 6, 2013 Share Posted August 6, 2013 If it helps, I have a used HS2 heatshield that I could be pursuaded to part with.... Quote Link to comment Share on other sites More sharing options...
Deleted User Posted August 6, 2013 Share Posted August 6, 2013 Get the 1500 carbs a whole lot better.I had 1500 carbs on my 1300 fab. Quote Link to comment Share on other sites More sharing options...
JP Posted August 6, 2013 Author Share Posted August 6, 2013 npanne wrote:If it helps, I have a used HS2 heatshield that I could be pursuaded to part with....YGM Quote Link to comment Share on other sites More sharing options...
JP Posted August 6, 2013 Author Share Posted August 6, 2013 Aaaaaaaaaaa information overload...With funds being a bit tight atm (anyone wanna buy a mk5 golf gti? :-/ ) I think I will try and make do with what I have and hope to pick up some HS4's for cheap as there must be some out there. It maybe that my toledo lump might not benefit from HS4's after what Richard B is saying so wouldn't want to throw 3 figures of cash away on a lost cause.Have to say Chris that webber stuff looks the nuts and would favour that over spending 3 figures on some used HS4's .. btw my fuel filter eventually arrived today so shall be fitting pump tonight 8)Many thanks for the responses this forum is ace. Quote Link to comment Share on other sites More sharing options...
Clive Posted August 6, 2013 Share Posted August 6, 2013 Which exhaust manifold do you have? the cast one with a single downpipe? if so, consider getting hold of a toledo/dolly 1300 inlet manifold for a single HS4. Even with that single carb (easy to set up etc) you will be getting virtually identical performance as twins (there was a proper artical back in the 90's about just such a conversion with RR reports etc)You could fit an HS6/HIF44 to get more power.... Quote Link to comment Share on other sites More sharing options...
CHRIS211083 Posted August 6, 2013 Share Posted August 6, 2013 Like this one???http://www.ebay.co.uk/itm/Classic-Triumph-Herald-Spitfire-Toledo-Dolomite-Inlet-manifold-SU-Carburettor-/221261515102?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Car+Make%3ATriumph&hash=item338436c95eChris. Quote Link to comment Share on other sites More sharing options...
Clive Posted August 6, 2013 Share Posted August 6, 2013 yep. Though ask in the right place and it would be a lot cheaper. Sadly that manifold won't work with the twin downpipe cast exhaust manifold. Trust me, I tried. And after several attempts admitted defeat. If you can tig then it would be possible of course. Or use the 4 branch tubular manifold. Quote Link to comment Share on other sites More sharing options...
Blubayou Posted August 6, 2013 Share Posted August 6, 2013 Just for info, I used my stock 1300 carbs on a 1500 for quite a while and they were ok.I remember having K&Ns on them too with no issues, indeed they seemed louder than the correct 1500 carbs I have on now. 8)My own theory for why the 1500s were fitted with twin 1 1/2" carbs is rationalisation, as they would otherwise be the only car in the entire range at that time to be fitted with 1 1/4" carbs. Quote Link to comment Share on other sites More sharing options...
JP Posted August 6, 2013 Author Share Posted August 6, 2013 cliftyhanger wrote:Which exhaust manifold do you have? the cast one with a single downpipe? if so, consider getting hold of a toledo/dolly 1300 inlet manifold for a single HS4. Even with that single carb (easy to set up etc) you will be getting virtually identical performance as twins (there was a proper artical back in the 90's about just such a conversion with RR reports etc)You could fit an HS6/HIF44 to get more power....Some Pics as hear you guys like pics on here ;) I think I'll persist with the HS2's for now as it goes well enough when it's not chucking fuel all over the shop ??) which will hopefully soon be resolved Quote Link to comment Share on other sites More sharing options...
HMaze Posted August 7, 2013 Share Posted August 7, 2013 Hi JP,before thinking about bigger carbs, i would think about better airfilters first.Harry Quote Link to comment Share on other sites More sharing options...
JP Posted August 7, 2013 Author Share Posted August 7, 2013 2250 wrote:Hi JP,before thinking about bigger carbs, i would think about better airfilters first.HarryWhat are ones to get? I seem to have mislaid the original airbox as I would put that back on if I had it. Quote Link to comment Share on other sites More sharing options...
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