ap72 Posted September 29, 2011 Share Posted September 29, 2011 I'm trying to figure out what I need for cam selection in my L28ET build. It's running megasquirt right now and I'm planning to do a head, cam, and turbo upgrade all at once. The head will be ported with stock valve size, ported stock intake manifold, 240sx throttle body, 24lb fuel injectors, hahn supersport 16G turbo, ported turbo exhaust manifold. I'll probably start around 10psi and work from there, water/Meth injection in the future. For my cam I'm considering a 220/220 .460/.460" cam on a 114 LSA. Is this too much cam for a car that only sees 2500-6000 RPM? Quote Link to comment Share on other sites More sharing options...
Gollum Posted October 4, 2011 Share Posted October 4, 2011 Who's doing the head? They should be the one recommending what cam to use, as it should match the head flow. If you're doing the headwork yourself then I'm surprised you're even wanting to go with an aftermarket cam. If you're going for that cheap DIY angle I'd be getting a 240Z "a" cam. And 24lb injectors is TINY unless your goal without the meth is only around 250wheel hp. It's much easier to get quality large injectors to idle nice than it is to get tiny injectors to make big HP. I'd recommend 30lb MINIMUM. Ideally I'd say go closer to 40-50 lb and don't buy generic, and try to get some that come with flow data to show that they're closely matched. And remember, if the head is flowing well, 10psi might already have those 25lb injectors maxing out at stock rail pressure. Go through big phil's videos and find the video of him and another member on here dyno'ing their cars. Big phil had a stock head and was pushing like 25 psi and wasn't hitting 400whp. The other guy was running in the lower teens iirc and was making MORE power... But he also had a professionaly built head with a well matched cam and intake system. It makes a BIG difference. Quote Link to comment Share on other sites More sharing options...
FricFrac Posted October 9, 2011 Share Posted October 9, 2011 (edited) Isn't it the later "A" grind from the N42/N47/P79 you want to use the the P-90 head? http://atlanticz.ca/...s/cam/index.htm There is a "K" grind I've come across here in Canada. Didn't see it listed and I'm not sure what it's specs or suitability would be. Regardless the "A" grind is the hot cam for the turbo up to 400HP IIRC..... If you're running 10lbs of boost I'm assuming/hoping you're running an intercooler as well? Edited October 9, 2011 by FricFrac Quote Link to comment Share on other sites More sharing options...
ap72 Posted October 11, 2011 Author Share Posted October 11, 2011 I know the injectors are small, but its all I could find on hand, eventually I'll be running 40lb's, the 24lb units will be enough to get me up and running though, which is all I really wanted. I'm doing my own head, I always do my own heads weather its Fords, Chevys, or now a Nissan. Sending a head off to be done for a grand or better for a street car is just foolish IMO. I'm just looking for some cam advice from some people who have "been there done that." Surely SOMEONE on this forum has BTDT? Quote Link to comment Share on other sites More sharing options...
Gollum Posted October 11, 2011 Share Posted October 11, 2011 Well you've come to the right place. Check out the L-specific threads in the FAQ section of the forum. People have done builds all from 300-700hp on L blocks on this very forum. Most are pretty well documented as well. Check out BRAAP's threads in which he goes through head work stuff, you can pick up on some of the key points to focus your headwork. And as far as the "been there done that", my advice stands. Find the "A" nissan cam. It's a great cam for turbo application and has shown to put down better numbers than some aftermarket "turbo" cams. Also, what's your goals with this build? 300whp? 350, 400, 450, 500? You'll find hundreds of builds like mine running mostly OEM longblocks, because it does fine getting you to 300hp, at which point the car becomes a handfiul. Quote Link to comment Share on other sites More sharing options...
ap72 Posted October 11, 2011 Author Share Posted October 11, 2011 300hp at the wheels would be nice. Then I would look into building a short block. The "A" cam is just too small for what I want. Doing any headwork with lifts that low is almost pointless, I'm looking for .450-.500" lift, changing the springs isn't an issue I just want something that will be durable, peak around 6,000 RPM and be mild enough to pull away from a stop sign in second gear with little trouble. Quote Link to comment Share on other sites More sharing options...
Gollum Posted October 11, 2011 Share Posted October 11, 2011 My suggestion would be to look into sunbelt cams, and other people that have made L specific cams. This might not mean much on turbo application, but several people's research indicates that the majority of common aftermarket cams out there were designed around other brand engines and their valve train, namely BMW. Sunbelt is among the few that actually designed aftermarket cams around the L motor's drivetrain geometry and ended up being able to make larger lift and duration cams that could use factory seat pressure just fine with no float issues. Most cam retailers offer L cams will tell you to upgrade springs for anything other than a mild upgrade, while people were making substantially improved power with minimal seat pressure on cams actually designed for the motor. The old timers in this field is isky, and are highly recommended by many. Many a builders have used their cams with GREAT sucess. 715149 is their part number for their stage 3 cam, which is basically a high lift cam with slightly more duration than a stock cam. I believe isky will also do custom grinds if you want more lift with less overlap, specifically for turbo application. Also, just their stage 1 cam would be more than youre .460 lift you were looking for, at .475, with 222 degrees of duration. I'm not sure what the lobe centers are. That 222 degrees is the same duration (or nearly so) as a stock turbo cam would have, and roughly 10 degrees less than the 240Z A cam mentioned. This should show that running a little more duration isn't exactly a bad thing on a turbo application, seeing as the "A" cam does so well. I'd go with the stage 2 or 3 isky cam if you go with isky. 300whp is easy btw. Add air with extra boost or better flowing head, and make sure you have an ECU that can tune it. The stock turbo will be way out of efficiency at that power level, but a well sized T3/T4 hybrid would do the trick. Some people have used Holset turbos with success too. 300hp is old hat, and easy to do. People have done it a million different ways. There's no "magic setup". I can say "well this is what you need to do" then I can show you a build that contradicts me. People have done it with bone stock longblocks, stock turbos, and stock injectors, and even with stock ECUs. I can't think of any that used ALL of those stock parts, but some have come close. One guy using stock injectors had his rail pressures over 100psi and used a twin pump setup. Some people using stock turbos use meth/water injection to combat the heat. Some using the stock ECU use RRFPRs with a larger turbo closer to it's peak efficiency in that application to get there. For most purposes, 400whp is the point at which things become sketchy. At that point the stock pistons will blow head gaskets and ringlands with mild detonation, that's usually very hard to catch before it's too late. What I've heard people say, which I think is great advice, is to tune your ECU on junkyard bottom ends. If you blow it up, go get another. No big deal. Then when you've got your tune solid and you're pushing your power goals on stock pistons, then build up your forged piston bottom end. You can easily blow up your forged pistons due to a bad tune at 400hp. Get the tune straight FIRST, then you won't be wasting money. No a requirement, just advice from people who've been there. Quote Link to comment Share on other sites More sharing options...
ap72 Posted October 11, 2011 Author Share Posted October 11, 2011 the 16G turbo I'll e using is about maxed out at 380ish flywheel hp, so after I get to that point I will be upgrading to a 20G compressor side (good for 500 flywheel hp). I'm trying to get everything lined up just right so I can hit my 300hp at or below 6000 RPM with as LITTLE boost as possible. I would like to get there with about 10-12psi. To do that I need to have everything as good as I can get it. I realize people can hit 300hp in NA form, but since I'm trying to use as many stock parts as I can I will be much more limited. My main concern with going larger than 220 (or 222 like the Isky cam) is off idle driveability. I know many peopl eon here like to spin their engines to the moon, but if I can make the same power at a lower RPM then that's what I'll go for. My choke will be the intake. Even with it hogged out as far as I can go I know it will be my restriction, so I need to build around that. Quote Link to comment Share on other sites More sharing options...
Gollum Posted October 11, 2011 Share Posted October 11, 2011 You my friend, seem to have a good head on your shoulders. And just so you know, your goals are entirely realistic. Focus on good chamber work and you'll be fine, despite the terrible intake. Past 300hp I'd seriously consider a better intake of course, but we're all limited by certain things, like money, and as such few actually take the time to make or buy a quality intake for their L motor. Quote Link to comment Share on other sites More sharing options...
ap72 Posted October 11, 2011 Author Share Posted October 11, 2011 You my friend, seem to have a good head on your shoulders. And just so you know, your goals are entirely realistic. Focus on good chamber work and you'll be fine, despite the terrible intake. Past 300hp I'd seriously consider a better intake of course, but we're all limited by certain things, like money, and as such few actually take the time to make or buy a quality intake for their L motor. Ive built a few engines in the past, but never an L28. I'm also putting together a Ford 2.3L powered car at the same time so whenever I get busy on one the other takes a rest. Right now I'm in the process of figuring out the cam I want for the L28 and until I get that I'm doing Body work on the other car. Then I'll be doing body work on the 280Z until I can fab up a new intake for my Ford engine. I plan one while I work on the other, that way I'm not rushed into doing something. Are there any members who have installed cams that I can talk to about drive-ability? I'm wanting some first hand experience and I'm having trouble finding someone I can discuss drive-ability with. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 11, 2011 Share Posted October 11, 2011 (edited) The 'stage 1' isky is listed as 270 degrees advertised duration(.006 lift?), the stock turbo cam is 240 advertised. I have not measured it, but from looking at MANY other cams, there is no way that the stock turbo cam has 222 at .050, probably closer to 180. Why the isky catalog says that the stage 1 has LESS duration than the stock cam, I have no idea. http://www.atlanticz.ca/zclub/techtips/cam/index.htm http://www.iskycams.com/pdf/2010Catalog-Full-Catalog.pdf Edited October 11, 2011 by letitsnow Quote Link to comment Share on other sites More sharing options...
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