Seedy Al Posted June 20, 2016 Share Posted June 20, 2016 Hey guys Just pulled the head off a mini, after it dropped a valve. 5 out of 8 broken valve springs from clearly and over rev Any one have recommendations for an Uprated valve spring setup to suit a 1275? Anyone done anything thats tried and true? Cheers for any info. Quote Link to comment Share on other sites More sharing options...
tortron Posted June 20, 2016 Share Posted June 20, 2016 Uprated single are better* than double They sit properly and will be fine for you Quote Link to comment Share on other sites More sharing options...
Celica RA45 Posted June 20, 2016 Share Posted June 20, 2016 eskederian mini minor springs are the go 1 Quote Link to comment Share on other sites More sharing options...
BLIZZO Posted June 20, 2016 Share Posted June 20, 2016 Yea all recommendations I am hearing now say to stay away from doubles. Don't go too much seat pressure either or it will rob all of the neddies and just fuck rocker gear. Kelfords sell a range of springs for reasonable prices depending on the cam it's got etc 1 Quote Link to comment Share on other sites More sharing options...
BobbyBreeze Posted June 20, 2016 Share Posted June 20, 2016 Nothing wrong with doubles as long as they are specced correctly - open & closed loads suitable for the cam profile & rpm range, clearance to bind for valve lift etc. What cam is it running? They are not really needed with modern springs and cam profiles for road cars which is why most will recommend singles now. Remember valve springs are one of the most stressed components in 4 stroke ICE's and should be treated as a consumable when the motor gets rebuilt. They're probably original BMC doubles well past their used by date hence 5/8 sizzled. Kelford certainly can help you out, plenty of UK suppliers etc too if needed. 4 Quote Link to comment Share on other sites More sharing options...
Frosty Posted June 20, 2016 Share Posted June 20, 2016 Late model 1000cc engines run a double spring and are good for about 7500rpm, they also run a forged rocker arm which also helps in higher rpm work as they have far less deflection than the folded ones, also suffer less from rocker shaft and rocker tip wear. Watch out once fitted not to go much further than the 1275's red line as the cranks have a nasty habit of breaking at the center main journal if unbalanced. Built a heap of these when I was a younger man and always ran the factory 1000 springs even with the big 731 grind cams. They offer the low seat pressure needed for good scavenging but reduce float that the singles experience and they are oem so heaps of r and d behind them. Use the retainer as well. 1 Quote Link to comment Share on other sites More sharing options...
Seedy Al Posted June 20, 2016 Author Share Posted June 20, 2016 So had a measure Would seem this motor actually just has a factory cam Mini's are gay. Going to fit new replacement standards. Apparently this guy is not hard on the gear..... 1 Quote Link to comment Share on other sites More sharing options...
Celica RA45 Posted June 20, 2016 Share Posted June 20, 2016 you can just use the outers from eskederian for your mini nice spring i was using these in a gen 2 3sge motor Quote Link to comment Share on other sites More sharing options...
igor Posted June 20, 2016 Share Posted June 20, 2016 BMC 1800 springs will fit sweet. They are the same external diameter but have thicker coils. Quote Link to comment Share on other sites More sharing options...
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