eric Posted October 23, 2003 Share Posted October 23, 2003 As the A2 cam comes directly without modification as the lift of an A2 is less important than with the 234 but the duration longer than 234 Could you think that the A2 is better for the valve life than the 234 your driving experience : A2 or 234 same or different behind the wheel Many thanks Eric Link to comment Share on other sites More sharing options...
greg Posted October 23, 2003 Share Posted October 23, 2003 Go for a 244 😬 or even 254 (that may be a bit wild!). I run a 264, which is a bit of a pain, but great when it comes on cam! Greg, Q 86 NTM (slow Green XFlow) Link to comment Share on other sites More sharing options...
eric Posted October 23, 2003 Author Share Posted October 23, 2003 244 better than 234 ? For fast road I mean eric Link to comment Share on other sites More sharing options...
greg Posted October 23, 2003 Share Posted October 23, 2003 I mean fast road as well. A 244 has higher lift and longer duration than a 234 ISTR. ISTR that the 234 is a more modern design than the A2. Greg, Q 86 NTM (slow Green XFlow) Link to comment Share on other sites More sharing options...
oilyhands Posted October 23, 2003 Share Posted October 23, 2003 The A2 is an old Cosworth profile designed for the pre-crossflow, the 234 has more lift and less duration so it will feel less 'cammy' and in a car as light as a seven the 244 might be a better bet. Oily Link to comment Share on other sites More sharing options...
eric Posted October 23, 2003 Author Share Posted October 23, 2003 Do you know the average power of a 1600 with stage 2 head with 244 twin webers 40 std bottom end or if I go further, a 1700 or 1760 (still reliable I think) based on ax block with stage 2 Burton head and forged piston weber 40 Many thanks again eric Link to comment Share on other sites More sharing options...
eric Posted October 23, 2003 Author Share Posted October 23, 2003 stage 2 Burton head is : 1.555 inch inlet 1.340 exhaust eric Link to comment Share on other sites More sharing options...
rgrigsby Posted October 23, 2003 Share Posted October 23, 2003 I had a 244 in my last Xflow it was superb with 3D mapping.... Rob G www.SpeedySeven.com Link to comment Share on other sites More sharing options...
Roger King Posted October 23, 2003 Share Posted October 23, 2003 Yes, the A2 is better for the life of the valve gear, but the 234 gives a lot more power with tractability at least as good if not better. With the right valve springs (not the ones that Caterham use), the 234 shouldn't shorten valve gear life too much. Link to comment Share on other sites More sharing options...
eric Posted October 23, 2003 Author Share Posted October 23, 2003 Right valve spring, do I understand : VS7 Link to comment Share on other sites More sharing options...
greg Posted October 23, 2003 Share Posted October 23, 2003 Anyone any suggestions for springs for a 264? Or are the Kent springs the best? Greg, Q 86 NTM (slow Green XFlow) Link to comment Share on other sites More sharing options...
eric Posted October 24, 2003 Author Share Posted October 24, 2003 From my last book on caterham, seems to be VS39 Link to comment Share on other sites More sharing options...
Roger King Posted October 24, 2003 Share Posted October 24, 2003 The best springs for a 264 are from the Hart 420R. Unfortunately they are currently made from Unobtanium. Failing that the Isky works well, but MUST be changed regularly to avoid breakage if very high revs are to be used. Link to comment Share on other sites More sharing options...
greg Posted October 24, 2003 Share Posted October 24, 2003 Anyone any ideas on an Isky Part number? Are they stamped on the spring(s)? Greg, Q 86 NTM (slow Green XFlow) Link to comment Share on other sites More sharing options...
Petrolhead Posted October 24, 2003 Share Posted October 24, 2003 I ran a 244 and it was very tractable in fact I recon the 254 would probable be ok in a well sorted engine. I'm back Link to comment Share on other sites More sharing options...
Iamscotticus Posted October 16, 2020 Share Posted October 16, 2020 Bump.This is still a very good subject: 234 or 244 for a road only seven? Will see a lot of time averaging 60-75 Mph (96.5-120.7 Kph) and see a lot of sierra box overdrive on tall 13" wheels. Link to comment Share on other sites More sharing options...
Roger King Posted October 18, 2020 Share Posted October 18, 2020 Either a 234 or 244 will work well on the road, but only if the rest of the engine is uprated to suit - forged pistons, decent big-end bolts, doweled flywheel, tufftrided crankshaft, properly flowed head, decent dizzy or 3D map (preferable), better valve material (and possibly bigger too), higher compression ratio, uprated rocker shaft, better valve springs, rejetted carbs with different chokes, etc, etc.The 234 is slightly better at low revs and the 244 gives a bit more top end as you would expect, but both are fine on the road. 3D mapping or injection would be the icing on the cake. Even a 264 can be road drivable when set up properly; my test for road use was "can I sensibly drive it in a multi-story car park?" which may seem a bit odd, but light throttle and low revs are much harder to set up for than outright power. By the way, a 264 will need a lot more engine changes than listed above.The Caterham Supersprint uses a 234, but they came nowhere near getting the best from it. I used to see around 120bhp from the later ones, but we had at least one super-special engine that achieved just over 150bhp on the same cam. Link to comment Share on other sites More sharing options...
Iamscotticus Posted October 19, 2020 Share Posted October 19, 2020 Any conrod upgrade? As long as the pistons are out... Link to comment Share on other sites More sharing options...
Roger King Posted October 19, 2020 Share Posted October 19, 2020 You can always use steel rods, but if you're sticking to 7000rpm the standard item is generally fine so long as they are checked for cracking and they are then balanced as a set.If you polish the flanks of the rods in addition to the above you can normally extend to 7200rpm. See photo.Please note that the above is given as generalised advice only and may not apply to a specific engine specification. Link to comment Share on other sites More sharing options...
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