Guest bastaad525 Posted June 17, 2005 Share Posted June 17, 2005 Z-Gad' date=' I see. stroker mph...... Bastaad525, Sounds like your engine is falling off too fast. Should make good power until 4.5 or 5K (just like you want). Maybe stronger valve springs or some 0.040" spring shims would help. Play around with the ignition timing. A little more advance will give you a little more rpm. Is your fuel pressure maintaining during high rpms? Another stock pump in parrallel would help keep the pressure up during high volume demand. Are you using the stock wastgate? I feel the stock wastegate is restrictive as compared to a striaght pipe off the turbo used with an external wastegate. I think you could get the stock T3 running much better.[/quote'] Well, a couple things. I have seen other people dyno their T3 setups and torque always does start to fall off right at about the same RPM, though never as rapidly as mine does. My timing is already advanced as far as I dare, 3* advanced from stock. Or it might be 2* now I forget it's been a while, but I dont' want to push it any further at 13-14psi on 91 octane. When I dynoed last, and was tuning the RRFPR, I made it a point to watch the fuel pressure gauge during the runs, and yeah, fuel pressure was holding steady... it fell of a little bit BUT, that was because boost was falling off as well, my boost would go from 14psi at onset, to 10-11psi by 6000rpm. So the fall in fuel pressure is a response to both RRFPR and stock FPR losing that bit of signal. My air/fuel ratios were fine however, it's not running too lean at high RPM anymore and so, shouldn't account for the torque falling so fast. Yes I'm using stock T3 with stock wastegate. Upgrading is not really an option. Sleeper - sad to hear you're not really doing much with your Z but glad to see you're still around and haven't forgotten about us. I find your posts have always been some of the most informative and would hate to lose such a wealthy source of knowledge. Quote Link to comment Share on other sites More sharing options...
z-ya Posted June 17, 2005 Share Posted June 17, 2005 Can you post the dyno plot? I'm wondering how much torque you lost in the lower RPMs with this cam. The stock turbo cam is good for well over 300WHP, and it keeps your torque curve nice and flat. Sounds like your turbo is limiting your power over 5000RPM with the stock turbo cam. That is a lot of boost pressure for only 300WHP. With the stock turbo cam, and a freer flowing turbo, you should be close to 375WHP at 17psi. I just finished tuning a customers car. Stock L28ET long block, P90 head. T04E/T03 turb with stage 3 turbine. 3" exhaust, Wolf 3D EFI with direct fire ignition. Boost spools to 10psi, and then creeps to 13psi. Hear is the dyno plot from a dynapack: Quote Link to comment Share on other sites More sharing options...
Z-Gad Posted June 17, 2005 Author Share Posted June 17, 2005 Sorry, I don't have access to a scanner to post the graph, but will do my best to describe what you have requested. Regarding the torque plots, the ISKY cam's curve is very linear and above the the stock cam until ~2900 rpms. There, the stock cam's curve rises just above the curve of the ISKY until it kind of plateaus at 290 TQ or so at 3800, peaks to 302 at 4500 and torque starts dropping off at 4600. The ISKY cam's torque curve is nearly identical to the stock cam from 2900 rpm's to around 3800 rpms where it rises above the stock cam, plateaus ~4200 and starts dropping off around 5200 rpms. Regarding the numbers, the dyno operators said that their Mustang dynamometer, from trial and error, tends to read 5-15 percent below other dynos in the area. For me, it doesn't really matter. The numbers are what they are and were performed on the same dyno. That was what mattered to me. This experiment was done to see what difference changing only the cam would make with a larger frame turbo, making only minor air/fuel corrections to compensate for the new cam, and post results. I have not seen any data on solely a cam change, so I did it. I agree that there may be more horsepower to be made and the tune of the car is not optimum at this time. Perhaps the turbo is not perfect for a stock L28 and I am unable to take advantage of it. maybe the advantages of the larger turbo would shine above 20psi... Maybe a T3/T4 is better suited for the stock cam. I guess there are other questions and experiments to be run besides the one I just did... I would like to see someone do solely a cam change with a stock T-3 and see what would happen. Any takers?? Ok, enough thinking out loud for now... Quote Link to comment Share on other sites More sharing options...
wigenOut-S30 Posted June 17, 2005 Share Posted June 17, 2005 I would love to.. and might.. eventually.. only thing is money for me right now.. i am trying to save for SEZS6.. heh.. someone want to donate a cam?? A man can dream right??.. hehe Quote Link to comment Share on other sites More sharing options...
Drax240z Posted June 17, 2005 Share Posted June 17, 2005 I would like to see someone do solely a cam change with a stock T-3 and see what would happen. Any takers?? I hope to have a lot to add to these type of discussions soon. My Dyno Dynamics unit shipped out of Louisiana today. I should have it in my shop here and set up in less than 2 weeks! Believe me I will be using it a lot for my Z, and I will share the info as I can. Included in this will be a comparison between stock and aftermarket cams on my setup, whenever I get around to getting a new cam. (won't be too terribly long) Great info though! Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted June 18, 2005 Share Posted June 18, 2005 I hope to have a lot to add to these type of discussions soon. My Dyno Dynamics unit shipped out of Louisiana today. I should have it in my shop here and set up in less than 2 weeks! Believe me I will be using it a lot for my Z' date=' and I will share the info as I can. Included in this will be a comparison between stock and aftermarket cams on my setup, whenever I get around to getting a new cam. (won't be too terribly long) Great info though![/quote'] That is VERY good news... something that I think could really benefit the L28ET community, an owner with his own dyno... nice. I may eventually install a hotter cam with my stock motor/T3 as well, and will definately re-dyno afterwards. Probably not for a long time though. Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 6, 2006 Share Posted June 6, 2006 I ordered the Isky cam with Z-Gad specs. Problem is when it came, the exh. spec. is off by 2 degrees from what I ordered. Per spec. it's supposed to be 266, I got 268 (Isky print out, and stamping on back of cam). What would you guys do? Z-Gad watcha think about 2 measly little degrees? Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted July 25, 2006 Share Posted July 25, 2006 is it just me .. or is it weird DemonZ posted on 6-6-06 .. haha .. Quote Link to comment Share on other sites More sharing options...
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