JackyBoi Posted June 29, 2015 Share Posted June 29, 2015 I'm looking into buying some 264 camshafts for my VVTi Supra but am curious into what the actual benefits are, and as I'm no mechanic I thought why not ask you guys: Does having higher lift cams installed increase horsepower/torque, and if so how much? Can they be detrimental to any engine/turbo components? Anything else worth upgrading when fitting higher lift cams? Thanks guys Quote Link to comment Share on other sites More sharing options...
Scott Posted June 29, 2015 Share Posted June 29, 2015 In laymens terms they basically hold the valves open for longer. This means that more air can get into the chamber during a stroke and more gas can get out of the chamber during a stroke. Various combinations are used for various applications. If you check your dyno graph and notice a drop off in power then this would suggest that either your turbo is gassed or you could do with cams. There are pro's and cons. Adding longer duration cams will shift the power up the rev range a little. It allows for more power, but at a slight cost of low end power/spool. Fancy mapping can help iron this out though. If you are using stock cams, I would expect that at least 256 cams would make a difference. Being VVTi I'm not sure how just changing the exhaust cam works out. Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted June 29, 2015 Share Posted June 29, 2015 Am I right in thinking that changing the cams on a VVTi makes them noisy? Quote Link to comment Share on other sites More sharing options...
JamieP Posted June 29, 2015 Share Posted June 29, 2015 Am I right in thinking that changing the cams on a VVTi makes them noisy? Only on some cams, HKS are silent. Quote Link to comment Share on other sites More sharing options...
Chris Bailey Posted June 29, 2015 Share Posted June 29, 2015 Am I right in thinking that changing the cams on a VVTi makes them noisy? VVTI HKS Cams are okay, I believe I've read on here before Titan 272 VVTI cams are noisy. Quote Link to comment Share on other sites More sharing options...
Supraleeturbo Posted June 29, 2015 Share Posted June 29, 2015 Im getting Srd stage one 264 as my stock cams are at there limit ....http://www.mkivsupra.net/vbb/showthread.php?229575-SRD-Stage-1-2-and-3-Camshafts Mine is pre vvti but I'm sure it's beneficial to have cams mate Quote Link to comment Share on other sites More sharing options...
JackyBoi Posted June 29, 2015 Author Share Posted June 29, 2015 In laymens terms they basically hold the valves open for longer. This means that more air can get into the chamber during a stroke and more gas can get out of the chamber during a stroke. Various combinations are used for various applications. If you check your dyno graph and notice a drop off in power then this would suggest that either your turbo is gassed or you could do with cams. There are pro's and cons. Adding longer duration cams will shift the power up the rev range a little. It allows for more power, but at a slight cost of low end power/spool. Fancy mapping can help iron this out though. If you are using stock cams, I would expect that at least 256 cams would make a difference. Being VVTi I'm not sure how just changing the exhaust cam works out. That sounds about right. On 1.7 bar my car surges which I've heard could be solved with higher lift cams. Im getting Srd stage one 264 as my stock cams are at there limit ....http://www.mkivsupra.net/vbb/showthread.php?229575-SRD-Stage-1-2-and-3-Camshafts Mine is pre vvti but I'm sure it's beneficial to have cams mate Guessing those aren't priced for VVTi then. I was quoted over £1k for VVTi 264 cams, brand new. Quote Link to comment Share on other sites More sharing options...
Supraleeturbo Posted June 29, 2015 Share Posted June 29, 2015 I think he dose the bilit vvti cams for 800 I think Quote Link to comment Share on other sites More sharing options...
trebor69 Posted June 29, 2015 Share Posted June 29, 2015 I had 2.0L highlift cams in my 1.6 cortina and the revs seemed to go on forever, it extended the rev range in each gear. Quote Link to comment Share on other sites More sharing options...
Lee P Posted June 29, 2015 Share Posted June 29, 2015 I would recommend the HKS 264 cams for a VVTI As Jamie said they don't cause any noise and the gains are very good I can supply them if needed, just drop me a PM Quote Link to comment Share on other sites More sharing options...
johnny g Posted June 29, 2015 Share Posted June 29, 2015 I would recommend the HKS 264 cams for a VVTI As Jamie said they don't cause any noise and the gains are very good I can supply them if needed, just drop me a PM That was the one thing that let my car down. Go HKS, mate. Any other make and it sounds like a diesel from the 80's on idle. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 30, 2015 Share Posted June 30, 2015 Some profiles cause the VVTi actuator to rattle. The cams themselves are not the source of the noise. A high lift cam opens the valves wider, they do not *NECESSARILY* hold them open longer. Valve spring stress, retainer stress and cam lobe pressures increase. If they are pretty wild the lobes may catch on the bucket bores, or try and flick the shim biscuits out. Really wild ones will need under bucket shims, and custom cams may need larger diameter buckets and a lot of trick machining. Cheap cams are ground on stock blanks, and the extra lift produced by reducing the base circle diameter. You then find you need very thick shims. Quality ones are done on custom blanks or from billet. They should use stock range shims Quote Link to comment Share on other sites More sharing options...
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