hodge Posted March 7, 2011 Share Posted March 7, 2011 (edited) Hi guysDoes anyone have the valve clearance tolarence for the above cams please. I cant find my spec sheet anywhere and want to get Johnnys cams checked today before I go to work. Now Mr. T sais:- exhaust .010 - .014 inches or .25 - .35mm Intake .006 - .010 inches or .15 - .25mm I remember reading somewhere that the tolarence is smaller for aftermarket cams. Thanks John Edited March 7, 2011 by hodge (see edit history) Quote Link to comment Share on other sites More sharing options...
hodge Posted March 7, 2011 Author Share Posted March 7, 2011 I've been reading a few threads on SF and they are all recommending going to the high side of tolarence. This j's to compensate for heat expansion. What are your views on this. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 7, 2011 Share Posted March 7, 2011 If it was a competition engine you'd err on the tight side to maximise lift. I'd just aim for a middleish clearance. Quote Link to comment Share on other sites More sharing options...
Lee P Posted March 7, 2011 Share Posted March 7, 2011 I've been reading a few threads on SF and they are all recommending going to the high side of tolarence. This j's to compensate for heat expansion. What are your views on this. That sounds backwards to me, I would go on the tight side as you dont want it to rattle. You need to shim them to the specs provided with the cam. You can get the cam card from BC if you ask them. Clearences all depend on how the cams have been machined to get the profile correct, if the clearences are wrong the cams willl not perform as intended. You also need to dial them in correctly as well but in this case just the exhaust side as its VVTI Quote Link to comment Share on other sites More sharing options...
hodge Posted March 7, 2011 Author Share Posted March 7, 2011 What do you mean by dialing them in correctly. The cam is being set at TDC it a stock position. I wasn't going to advance or retard it via an adjustable wheel. Or have I got the wrong end of the stick here. Quote Link to comment Share on other sites More sharing options...
Digsy Posted March 7, 2011 Share Posted March 7, 2011 0.3 exhaust and 0.2 intake (i.e. the centres if the range quoted by Toyota) sound fine to me - assumning that the aftermarket cam profiles are also designed for a solid shimmed tappet, which you would hope, as its specified for a Supra. Quote Link to comment Share on other sites More sharing options...
hodge Posted March 7, 2011 Author Share Posted March 7, 2011 0.3 exhaust and 0.2 intake (i.e. the centres if the range quoted by Toyota) sound fine to me - assumning that the aftermarket cam profiles are also designed for a solid shimmed tappet, which you would hope, as its specified for a Supra. That's what I was thinking but I was reading some threads on SF and they were shunning them to top size because of heat expansion. Think I'll just go for mid tolerance, can't go wrong with that really. Quote Link to comment Share on other sites More sharing options...
Bailey. Posted March 7, 2011 Share Posted March 7, 2011 That's what I was thinking but I was reading some threads on SF and they were shunning them to top size because of heat expansion. Think I'll just go for mid tolerance, can't go wrong with that really. Mine were set in the middle of the 2 tolerances, the head was rebuilt by a local engine shop, but what is actually dialling in??? Quote Link to comment Share on other sites More sharing options...
hodge Posted March 7, 2011 Author Share Posted March 7, 2011 Mine were set in the middle of the 2 tolerances, the head was rebuilt by a local engine shop, but what is actually dialling in??? Eagerly awaiting Lee's reply lol. Quote Link to comment Share on other sites More sharing options...
Jurgen-Jm-Imports Posted March 7, 2011 Share Posted March 7, 2011 useful site http://www.angelfire.com/realm2/autotips/camdegree.html Quote Link to comment Share on other sites More sharing options...
Digsy Posted March 8, 2011 Share Posted March 8, 2011 That's what I was thinking but I was reading some threads on SF and they were shunning them to top size because of heat expansion. The stock clearances are there for heat expansion, so in theory if your cylinder head isn't running a stupidly high temperature, the stock clearances should be fine. There's no reason why you couldn't go to top limit if you can select / grind a shim to hit it exactly, but its a trade off between noise / durability and losing a fraction of valve lift. Quote Link to comment Share on other sites More sharing options...
johnny g Posted March 8, 2011 Share Posted March 8, 2011 Safety first please! Quote Link to comment Share on other sites More sharing options...
TLicense Posted March 8, 2011 Share Posted March 8, 2011 What do you mean by dialing them in correctly. The cam is being set at TDC it a stock position. I wasn't going to advance or retard it via an adjustable wheel. Or have I got the wrong end of the stick here. Definitely time it with an adjustable cam gear. Setting them correct to get the right valve overlap can make a reasonable difference to the idle quality. Quote Link to comment Share on other sites More sharing options...
johnny g Posted March 8, 2011 Share Posted March 8, 2011 Definitely time it with an adjustable cam gear. Setting them correct to get the right valve overlap can make a reasonable difference to the idle quality. I do have an adjustable cam gear, from Whifbitz. So, all good. Quote Link to comment Share on other sites More sharing options...
dude Posted March 8, 2011 Share Posted March 8, 2011 There should be info on the cam card for dialling the cam/s in correctly, ie X amount of lift at so many degrees before and after tdc. Quote Link to comment Share on other sites More sharing options...
hodge Posted March 8, 2011 Author Share Posted March 8, 2011 (edited) The cams didn't come with a cam card. And am I not better off leaving this to the mapper to alter cam timing when he's setting the car up. Edited March 8, 2011 by hodge (see edit history) Quote Link to comment Share on other sites More sharing options...
johnny g Posted March 8, 2011 Share Posted March 8, 2011 I'll get on to them. I feel I might have lost it when opening box.` Quote Link to comment Share on other sites More sharing options...
johnny g Posted March 8, 2011 Share Posted March 8, 2011 Haha... here you go.bc_0312.pdf Quote Link to comment Share on other sites More sharing options...
Lee P Posted March 8, 2011 Share Posted March 8, 2011 Looking at that yes leave it till the dyno and adjust the exhaust pully as needed. Quote Link to comment Share on other sites More sharing options...
hodge Posted March 8, 2011 Author Share Posted March 8, 2011 Looking at that yes leave it till the dyno and adjust the exhaust pully as needed. That's what I thought Lee. I don't want to spend time adjusting this when it's going to have to be done all over again. Ok were all sorted now. Thanks everyone for there help and input. Quote Link to comment Share on other sites More sharing options...
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