skirkland1980 Posted October 30, 2012 Share Posted October 30, 2012 I have an 83 280zx turbo. Mods are listed in my sig. Engine has all stock internals. P90a, dished pistons, etc. I'm considering a cam upgrade. Has anyone tried this comp cam? It's not much more than a stock cam but has a little more duration. Did you need thicker lash caps, retainers, springs? I already plan on changing to solid lifters. Should I just use the N42 cam that I already have or will neither be a worthwhile upgrade? I want more power while keeping the boost under 20psi. Thanks Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 2, 2012 Share Posted November 2, 2012 Why bother running a stock when a re-grind is SO inexpensive? I mean most good places charge $100 and shipping. Best advice I was ever given was to call Ron at Isky. Id say do the same before making any purchase. I do not know anything about the comp cam. But I bet Ron answers every question you have. Ray Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted November 2, 2012 Author Share Posted November 2, 2012 I was told, with a regrind, they can't adjust LSA. I was thinking about a 107 or 108 lsa since I have a pretty large exhaust a/r on my turbo. I'd like about .450"/.440" lift int/exh, around 220 duration @ .050 107 lsa. Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 2, 2012 Share Posted November 2, 2012 Ive had a 102 fever for about 24hours so my brain is a little fuzzy, but I dont see why you cant change LSA with a re-grind. Id talk to ron or BRAAP about lash pads. Some searching for lash pads on this site may help you. I could be wrong, but I dont see why they cant. If memory serves me correctly some cam towers are offset a little more, but I could be thinking of something else, but if thats true then that would play a role in lash adjustment as well as it adjusts the wipe pattern. Anyway Ill get off the computer now in case Im spouting non-sense. Ray Quote Link to comment Share on other sites More sharing options...
Xnke Posted November 3, 2012 Share Posted November 3, 2012 (edited) You can change the lobe seperation angle on a regrind. Ron is cutting my stock turbo cam core from 110LSA to 113 right now. The issue is that you loose more base circle diameter and have to run larger lash pads. And no, you do NOT necessarily want a 107 LSA! The stock turbo cam is cut on a 110, and would suit well for a core. Call Ron at Isky, but call after 2PM pacific time. He has a few turbo grinds already; most have standard-for-him lobes, but are cut with different opening and closing points. It's not all about LSA, but more where the intake valve closes and the exhaust valve opens. Edited November 3, 2012 by Xnke Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted November 27, 2012 Author Share Posted November 27, 2012 I've already called him about a year ago. He recommends a cam that requires me to buy their springs, their retainers, and thier lash pads. It states in the datsun bible that more than .460" lift is not necessary for street applications. Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 27, 2012 Share Posted November 27, 2012 What exactly is 'the datsun bible' and I don't know what they're on, but 460 is the limit on STOCK SPRINGS, nothing more. I wouldn't BOTHER with a cam that didn't give me close to 500, ESPECIALLY with a turbo... If you aren't porting the head, go look at the flow available from the stock ports versus lift. At the point where your flow stops increasing....that is the lift you want on ANY cam to maximize the flow potential of the port. This goes as well for ported heads. I shake my head when I see guys putting in a 620 lift cam, when their head stops flowing at 575 lift. All you are doing is beating your springs into early replacement. Get a grind that maximizes time at 575 lift, and you will be better off longevity wise. Turbos ain't NA's! If you aren't altering valve events to keep good vacuum and minimize overlap, your compensation is LIFT to get FLOW. And FLOW is where it's at.... The more flow you have, the less boost you use (or need)... Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted November 27, 2012 Author Share Posted November 27, 2012 The book I was referring to is the "how to modify your Datsun" At the end of page 63 and beginning of 64 is where I read about the unnecessary expense of cams larger than .460". What I want is to shift at 6500-7k when drag racing. I was thinking relatively stock lift and added duration will allow the engine to breathe as I approach those shift rpms. I do plan on porting my head. I was thinking about using one of my N42. I have a CNC machinist whom I want to just CNC port the intake port inlet about 1/2" in to a diameter up to about 42mm. Then I will hand blend the rest. This N42 also appears to need a good bit of porting around the exhaust valve guide. What's your view Tony? Quote Link to comment Share on other sites More sharing options...
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