dr_hunt Posted June 8, 2006 Share Posted June 8, 2006 I think that all the people are in agreement, that would be an issue if you had ordered a cam with 44 degrees of overlap. Keep us informed. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 8, 2006 Share Posted June 8, 2006 FWIW, I also run the Isky 7181 cam in my car. Not sure how accurate this is, but here's the difference Desktop Dyno see's between the 7181 and 7151 cams. The top line with the dots is the 7181. Both cams were setup with a 3.0L L28 and a mild P90. My dyno numbers with the Isky 7181 cam match this chart pretty closely if adjusted for drivetrain loss. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted June 8, 2006 Share Posted June 8, 2006 Do you have a Auto range hp/tq w/ mid range RPM. How the hell did you get that thing even near 500? When I use DD for an L that's a 1mm over 2.8 11.6:1cr I get close or at 300hp. The specs that are in my sig basically. Oh, is it forced induction? Isk Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 8, 2006 Share Posted June 8, 2006 Do you have a Auto range hp/tq w/ mid range RPM. How the hell did you get that thing even near 500? When I use DD for an L that's a 1mm over 2.8 11.6:1cr I get close or at 300hp. The specs that are in my sig basically. Oh' date=' is it forced induction? Isk[/quote'] I posted and noticed I had the hi-range on the RPM. I fixed it and reloaded the chart. Everything else is mid-range. Yes, my car is a turbo. Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 8, 2006 Author Share Posted June 8, 2006 I'm not familiar with DD. As far as I can see, 7181 (hollow core, 2 degree adv.) and 7151 are the same. If so, then the chart above shows what a 2 degree advance would do (if DD claim of 5% accuracy is true). It would seem then that the curves "should" resemble more of a phase shift rather than an absolute lifting of whole curve since adv/ret. of camshaft mostly moves the powerband up or down the rev. range, generally speaking. The chart shows ~25hp/25# peak differences, not a side to side movement. Am I missing something? The good news is, there is a real world user running 7181 and making good power up top!! WooHooo!!! jgkurz that is what I wanted to hear! What's the idle and driveability like? Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 8, 2006 Share Posted June 8, 2006 The chart shows ~25hp/25# peak differences' date=' not a side to side movement. Am I missing something? The good news is, there is a real world user running 7181 and making good power up top!! WooHooo!!! jgkurz that is what I wanted to hear! What's the idle and driveability like?[/quote'] You aren't missing anything. In DD the 7181 seems to allow gradually better flow above 2500 RPM hence slightly more HP than the 7151. An interesting side note, when I was making changes in the simulator the single greatest HP gain other than a fully ported head was to enlarge the exhaust valves. A typical upgrade I've seen is to use a 3mm oversize valve in the L series head. In DD it made about a 50HP gain. Strangely, changing the intake valve size made little difference. My car has a very slight lope with vacuum at 12 to 14 inches. With my ignition timing at 15 degrees and idle RPM at 750, I get about 14:1 AFR. Any leaner and it idles too rough. I'm happy with the cam but my head needs more work to flow it's full capabilty as peak power at 5500 RPM would indicate. Driveability is fine. I didn't notice much if any low end torque change vs the stock cam. Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 8, 2006 Author Share Posted June 8, 2006 Great to hear! Funny I got new SS +3 exh. valves TURNED DOWN 2, so I wouldn't have to eyebrow the block. Oh well, shoulda woulda. I think I will keep the cam after all. Thanks. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted June 8, 2006 Share Posted June 8, 2006 DemonZ, Where are you going to take your Z for dyno tuning? Aren't you in Bothell? I've been planning on taking mine to Fairlady Motors If you need a hand when you get to that point I'll glady help. Not like I'd be good for anything though. I'm actually hoping too see what I can pick up about turbos, LOL. Isk Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 8, 2006 Share Posted June 8, 2006 Are you guy's going to the Canby event? http://www.datsunsnw.org/canby06.html Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 8, 2006 Author Share Posted June 8, 2006 Thanks for the offer iskone. I'm in Renton. Haven't decided on just where to take it for tuning yet, I'm still a ways off from that. I still need to settle on an ECM and injectors. Quote Link to comment Share on other sites More sharing options...
Guest iskone Posted June 8, 2006 Share Posted June 8, 2006 I won't be able to go I have to work on my 72 this weekend. Check out Ebay and pick up some 440 supra injectors. They can be had cheap. I've seen em' work great too. Isk Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 8, 2006 Author Share Posted June 8, 2006 Shoot! That's this weekend?!! I have some relatives coming in on friday and must entertain. Don't think the 2 75+ year olds will have fun at a car show. Please take pics and post, so that I may live through you. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted June 8, 2006 Administrators Share Posted June 8, 2006 .......... I would rather not play guinea pig right now as I have all sorts of issues and sub systems to sort out before I can run it. So I just want baseline componentry for starters. To me' date=' the cam is still questionable in the 44 vs 57 overlap issue. I hope to have that resolved soon.[/quote'] As for the 44 vs 57 degrees of overlap, if the 57 degrees of overlap is equal to 114 Lobe centers, (still haven’t ran the numbers myself to verify the LCA), then I wouldn’t worry about it. That should be a great cam for a hot street Turbo engine. If it is on 114 LCA, I probably wouldn’t want the 44 degrees of overlap as that would put your lobe centers on 120.5 degrees LCA which seems to me a bit wide for a hot street turbo, though it wouldn’t surprise me if worked and ended up working well. I have seen a cam spec for a Turbo SBC that produced over 1000 HP and that cam had NO overlap whatsoever and it worked wonders for that application. Sorry that I don’t recall any more of the details of that power plant, I just remember that wild cam spec of NO overlap and over a 1000 HP. John Kurz, Thanks for posting. I had hoped that you’d see this thread and offer your opinion. You have much more experience and knowledge in regards to cams for Turbo charged L-series engines. Cam shaft design and specs are an art form for N/A power plants, but through a Turbo in the mix and AH MAH GAWD, it gets crazy!!! Turbos will respond to extreme wild lobe specs in different ways, such as the zero overlap cam mentioned above. That cam would run like CRAP on pretty much any N/A engine. As for the big Canby Datsun meet this weekend, we are planning to be there on Saturday as “Paul and Krystin”, not Rusch Motorsports, to sell a few of our personal used parts, maybe a couple Ron Davis Radiators that we have in stock as well in Mr. Lums vendor area, then we will bring the race car for Sunday since I got it up and running last weekend on MSnS-E with the Distributor less ignition. WOOHOO…. See ya there… Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 12, 2006 Share Posted June 12, 2006 I won't be able to go I have to work on my 72 this weekend. Check out Ebay and pick up some 440 supra injectors. They can be had cheap. I've seen em' work great too. Isk DemonZ - I just happen to have a set of cleaned and flowed 440cc injectors for sale. I ran them my Z for a short period. I swapped them out for larger 550's. Send me a PM if you are interested. Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 17, 2006 Author Share Posted June 17, 2006 Welp, after a week I figured Ron would never call me back, so I called him today. He said basically, the print out that came with the cam goes out the shipping end and is not the same as the one at the grinder's bench. Using his expression "...garbage in garbage out...", he pointed out other errors with the prints, (top page) in red for deg. int. and ex. duration is incorrect at 290 and 280 which SHOULD read 276 and 268 (like the bottom). He confirmed that infact the overlap is 44. (He faxed me another cam card but I couldn't downsize the pic and post here because my new puter doesn't have all my old SW installed yet.) Though he didn't come out and say it, we all got the wrong cam card. Fortunately for jgkurz's confirmation that the cam does work for him, I'll bolt it up and degree it to +/- 1 deg. and run it. Now I go shopping for ECM and injectors finally. Looking for 68#er's. BTW, thanks for the offer jgkurz but too small. Quote Link to comment Share on other sites More sharing options...
Drax240z Posted June 17, 2006 Share Posted June 17, 2006 Man, what an ordeal. I'm certainly going to think twice before I order a cam from them... Quote Link to comment Share on other sites More sharing options...
JIM73240Z Posted June 17, 2006 Share Posted June 17, 2006 check out these injectors. i just ordered some. http://www.racetronix.com/3145FM.html jim Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 18, 2006 Share Posted June 18, 2006 I have nothing but good things to say about Isky cams. My cam (p/n 7181) was ground on a new billet and was exactly what I expected from a performance and driveabilty standpoint. Man, what an ordeal. I'm certainly going to think twice before I order a cam from them... Quote Link to comment Share on other sites More sharing options...
rztmartini Posted June 19, 2006 Share Posted June 19, 2006 will the people at Isky cams help me decide on what profile i need? i am trying to figure out what the best duration/lift would be for my engine but am still really confused Quote Link to comment Share on other sites More sharing options...
jgkurz Posted June 19, 2006 Share Posted June 19, 2006 The folks at Isky can help but like most camshaft manufacturers generally are not experts on the L6. You will need to have some idea about what you want. HybridZ has a decent amount of threads discussing camshafts. If you cannot find what you need just start a new thread by listing your engine specs and perfromance desires. Hope that helps.... Quote Link to comment Share on other sites More sharing options...
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