Fishey Posted July 8, 2012 Report Share Posted July 8, 2012 Bigger cams add HP period! Even if the NA cams arent huge, and even if they added only 15whp, its still worth it seems they cost only $50. As fair as I remember, someone on the Euro forums did a before and after dyno test with NA cams and gained some decent HP. I have 93 NA cams, which I would also like to see if thet really are bigger than any other year? T5 cams versus GLT cams GLT Intake:250dr duration 8,45mm lift Exhaust:252,6dr duration 8,45mm lift T5 Intake:242dr duration 7,95 lift Exhaust:243,5dr duration 7,95 lift" Adding 17degrees total of duration is kind of a big deal. As I have always said just run the intake cam from an N/A not both. Link to comment Share on other sites More sharing options...
850wagonT5 Posted July 8, 2012 Report Share Posted July 8, 2012 Bigger cams add HP period! Even if the NA cams arent huge, and even if they added only 15whp, its still worth it seems they cost only $50. As fair as I remember, someone on the Euro forums did a before and after dyno test with NA cams and gained some decent HP. I have 93 NA cams, which I would also like to see if thet really are bigger than any other year? T5 cams versus GLT cams GLT Intake:250dr duration 8,45mm lift Exhaust:252,6dr duration 8,45mm lift T5 Intake:242dr duration 7,95 lift Exhaust:243,5dr duration 7,95 lift" Adding 17degrees total of duration is kind of a big deal. As I have always said just run the intake cam from an N/A not both. Dub, I was also reading last night that someone *lost* a good amount of power putting in the NA's on one of the euro boards. It's hard to come to a conclusion that way not knowing what their setup (or timing) was though. And yeah, lift is a hefty chunk of it...but unless you're talking about all of the variables in relation to each other (like duration...which is huge...and part of the reason I burnt a couple valves actually, because I was running too much duration which is bad for a high boost motor), then they don't mean all that much on their own. Half a mm of lift would be equal to the most mild, off the shelf cam options for most other cars out there...like upgrading to a 16T (almost the same as the 15G you had before) instead of going with something more worth while. I kind of think of it that way. BUT, while I haven't measured it, I've heard there isn't much valve to piston clearance in our engines - and that when you get to the 9mm lift area (about the same as the Piper cams, I think they're both 8.89mm I/E), you're running the risk of contact without having reliefs cut. How true this is, I don't know. But if I spec'd cams to be ground for me, I wouldn't do it for less than 9mm of lift or it wouldn't be worth it to me. If anyone knows what that clearance is, some of us would LOVE that info! ;) Link to comment Share on other sites More sharing options...
lookforjoe Posted July 8, 2012 Report Share Posted July 8, 2012 How true this is, I don't know. But if I spec'd cams to be ground for me, I wouldn't do it for less than 9mm of lift or it wouldn't be worth it to me. If anyone knows what that clearance is, some of us would LOVE that info! Enem Cams (y21) are new billet, not regrinds, and have 9.8mm lift . The recommended intake setting is 1.5mm @ true TDC. I can tell you that going 1/2 tooth beyond this will cause bent valves, so there is not much latitude. I have pics using a boroscope of exactly when valve contact occurs in my ongoing thread. Enem Cams also have cams with over 10mm lift, but with those you need custom springs, which they don't sell. Link to comment Share on other sites More sharing options...
Zappo Posted July 8, 2012 Report Share Posted July 8, 2012 Interesting. I am about to install a set of NA cams, but I guess I should only go with the intake it seems? I am trying to lower my spooling of the GT30 a few hundred RPMs and was thinking the exhaust cam would help with that, but there are trade offs. Link to comment Share on other sites More sharing options...
lookforjoe Posted July 9, 2012 Report Share Posted July 9, 2012 I just want to say 99.99% of all information listed about N vs RN heads is just funny from my point of view. Also, Joe no offense but you know nothing about cylinder heads and the same goes for almost everyone else on this forum. Yes, we are all peons at the feet of your majesty. And as usual, you don't provide any empirical data to back up your statements, Mr Know-it-all. Interesting. I am about to install a set of NA cams, but I guess I should only go with the intake it seems? I am trying to lower my spooling of the GT30 a few hundred RPMs and was thinking the exhaust cam would help with that, but there are trade offs. That was Lucky's reasoning - but that was also with a smaller turbo..... Link to comment Share on other sites More sharing options...
dublin14 Posted July 9, 2012 Report Share Posted July 9, 2012 If someone is losing power with bigger cams, then they have other things to sort out. Im not saying NA cams are big HP over Turbo cams, but combined with a big turbo - headworked - NA TB ect like I have and many others , the bigger NA cams will only help make more HP when tuned for them. Link to comment Share on other sites More sharing options...
850wagonT5 Posted July 9, 2012 Report Share Posted July 9, 2012 If someone is losing power with bigger cams, then they have other things to sort out. Im not saying NA cams are big HP over Turbo cams, but combined with a big turbo - headworked - NA TB ect like I have and many others , the bigger NA cams will only help make more HP when tuned for them. No. You aren't getting it. There are more factors to consider than just lift. Cams aren't simply "bigger." If the timing or overlap are off, then you can most certainly LOSE power even with a cam that has more mechanical lift. Link to comment Share on other sites More sharing options...
Fishey Posted July 9, 2012 Report Share Posted July 9, 2012 Yes, we are all peons at the feet of your majesty. And as usual, you don't provide any empirical data to back up your statements, Mr Know-it-all. As usual, you don't understand what the hell your talking about and all I got to say is.... That says all I need to say.. You "get it" or you don't... or that picture has the craziest optical illusion going on ever.. Link to comment Share on other sites More sharing options...
lookforjoe Posted July 9, 2012 Report Share Posted July 9, 2012 Yes, that is a pic of my RN cyl head from 2010 after my initial port cleanup, and before I had the machine shop cleanup/deshroud the intake valve area of the combustion chamber. I guess I don't "get it", and as usual, your obtuse remarks & lack of substantiating data when asked to back up your statements. This is UltraRunner's intake after several attempts at $$$ porting, This is another view of my RN head after mild cleanup, just enough to remove casting ridges, I didn't knife edge the divider. I also didn't need to grind the crap out of the valve guide, since the casting protrusion is greatly diminished on the later heads. You tell me which is easier (VVT issues aside), especially without flow-testing equipment to be certain that porting to an earlier head has not actually made it less efficient. The whole point of this was that anyone (all us peons who don't have access to machine shop equipment ourselves) can use the later head & benefit from the better flow characteristics off the bat. Link to comment Share on other sites More sharing options...
550 Posted July 9, 2012 Report Share Posted July 9, 2012 All about the bowl work... I think. Link to comment Share on other sites More sharing options...
Fishey Posted July 9, 2012 Report Share Posted July 9, 2012 From the picture atleast where is your choke? There seems to be no back cut at all to the valve seat. Without choke there is no flow as the air doesnt flow around the valve but instead flows directly into it. This is one of the many reasons valve stem size only helps a tiny amount. Link to comment Share on other sites More sharing options...
Fishey Posted July 9, 2012 Report Share Posted July 9, 2012 Double post Link to comment Share on other sites More sharing options...
dublin14 Posted July 9, 2012 Report Share Posted July 9, 2012 No. You aren't getting it. There are more factors to consider than just lift. Cams aren't simply "bigger." If the timing or overlap are off, then you can most certainly LOSE power even with a cam that has more mechanical lift. "If someone is losing power with bigger cams, then they have other things to sort out" "bigger NA cams will only help make more HP when tuned for them" Now you tell me how I DONT get why cams need proper setup? Its not the cams fault that a car loses HP? Its the setup and getting the car dialed in properly, thats why you have guys making HP and as you mentioned one lost HP. Setup... getting the car dialed in! All about the bowl work... I think. I know one the best guys in Toronto area for heads and motors called Beatty & woods where Ive had work done over the years. The bowel area he says is where he did most of the work on my Volvo cyl head. Link to comment Share on other sites More sharing options...
Fishey Posted July 9, 2012 Report Share Posted July 9, 2012 Dublin you don't understand duration. You can only run a cam so far both ways before you get negitive effects. The problem is that the duration of the N/A cams pushes you into overlap and that has negitive effects on a turbo car. Link to comment Share on other sites More sharing options...
dublin14 Posted July 9, 2012 Report Share Posted July 9, 2012 Dublin you don't understand duration. You can only run a cam so far both ways before you get negitive effects. The problem is that the duration of the N/A cams pushes you into overlap and that has negitive effects on a turbo car. Quite a few guys on here very happy with their cars after NA cam install. And as I said before, one of the Euro forums had a giy show I think 20whp after NA cam install. It either works or it doesnt. Turbo cams and NA cams with too much over lap can cause negative affects. Its just proper set that makes it work. Link to comment Share on other sites More sharing options...
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