Guest Anonymous Posted April 10, 2002 Share Posted April 10, 2002 Okay guys, This is my post of posts What I've been doing for a long time is trying to plan out my project/setup down to a 'tee'... Some basic info on my goals. Well, I want to reach 300 hp at the wheels, so I'm shooting for somewhere upward of 350 at crank. This is with a stock rebuilt (keeping stock pistons, only 60k on tthem) 2.8, 168 cubes and that's the way it will be until I break a piston, then I'll bore out and such. At 350, I definitely need at least a t04 compressor. I've ran so many maps and flow tests, various rpms, VE's, boost, you name it. I really haven't found any stock bottom-end l28et's that have hit 350hp, or at least how they did it. So far, I'm stuck between three compressors. t04e 50 or 57 trim, and the ultimate 60-1 compressor. I don't know what others used for their airflow benchmarks, I can't test the VE, but I usually conserve it to 85-90% at 4000-5500 rpms. The most boost I plan on running is 18 psi, and that's what I'm setting myself up for. I ran numbers at sites like turbofast and a site grumpyvette posted I finally got some lbs/min flow figures: http://www.smokemup.com/utilities/calc/airflow.cfm This was strange, because I've seen cfm/(lbs/min) conversion factors of like 14 and 13.5, but this site apparently used 12.93. Lbs/min is what I need to use the turbonetics comp. maps that I've been referencing from. Here's a excel bench chart I made from that site with my numbers http://www.angelfire.com/cantina/980mak/BOOST.xls whoa.. I think that site ERR on the high side. at 39 lbs/min at ~2.2 PR, an rough estimate at 10hp/#min would be 390 (via t'netics) ! Wow, I'd say realistically, that could be more like 35 lbs/min and 350 bhp. Has anyone else varified flow for a stock ZX bottom end? I will try and push VE to max by doing minor porting, good flowing system, t/b, etc., but I figure 90 is all I'll ever hit with the stock intake and exhaust manifold on a single turbo system and SOHC. Well, that supports all three proposed compressors. There is one issue with the 60-1, my favorite choice.. and that is the t4 turbine section, and how to adapt that to the stock exhaust manifold. I could just weld a t4 flange on there, but I think for costs I might as well just go for a t3/t04 hybrid. My 2nd area of decision would be selecting A/R ratio's. Obviously I'm going for a medium to large turbo for 350 hp, that really does its work in the last 1/3 of the rev range. I see all these hybrids for sale that provide like a .58 turbine section. No way! That would spool way too early and would never support big hp, boost, and at high rpm ranges. From MAX boost, I figure at the least a .8 turbine a/r would get me where I want. I really don't care about fast spooling at 2000 rpms, I want the full power at the upper rpms. T'netics sells a .82 housing, at largest. I figure I'd try and match that to compressor. Can anyone verify that with a 57 trim t04e would be able to produce 350 hp at say 5500 rpms, 168 cid, 90VE, and at most 18 psi, mid 70 compressor and intercooler (big spearco ) efficiency, and plenty of fuel, as little ign retard as possible. I might even go with watercooling to really shut out detonation. With sds em-3 6, coilpacks I should be able to control enough fuel to keep everything safe. Tell me what you guys think, approval? -980mak Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted April 10, 2002 Share Posted April 10, 2002 You have really done your homework. The TO4E 50 or 57 trim will get you anywhere you want to be with a L28 motor. I'm not sure you need a TO4 exhaust turbine, plenty of folks are running the stock T3 turbine on any of the compressors you mentioned, but the TO4 will definitely not have any flow problems at the top end. You should not have to run water injection - it just displaces fuel and air - with a good Spearco your intake charge should be cool enough. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted April 10, 2002 Share Posted April 10, 2002 If you will have an SDS F, big Spearco and only shooting for 300rwhp, you certainly do not need anything bigger than a t3/t04. With those components, you will make 300rwhp w/o even trying. My buddy has gone 11.74 @ 119 with the same setup at 19psi in a 240Z and that equates to about 350rwhp. I really don't care about fast spooling at 2000 rpms You certainly do not want the quick spoolup of the OEM t3 but do not sacrifice bottom-end because you only care about top-end power. With the correct t3 turbine side you can get what you want. Lag gets old real fast. as little ign retard as possible. I might even go with watercooling to really shut out detonation You might want to rethink your idea on ign retard. As SleeperZ said, ditch the water inj idea. With the Spearco and programmable capabilities of the SDS, it is not needed. Build your own ign and fuel curves to maximize power and eliminate detonation. That is why you have the SDS. Quote Link to comment Share on other sites More sharing options...
clint78z Posted April 10, 2002 Share Posted April 10, 2002 I pretty much beat this subject to death, do a search with my name and turbo related topics lots of info. If you use cast pistons 350rwhp is your limit, I would suggest sizing your turbo for this limit. The T04E-57mm stage III .63 A/R is what I have and on paper probably the best for the application. It will drop a bit of effeciency at 15+psi but still in good range. I would not recommend .82 A/R on a smaller turbo you are selecting, you won't gain much topend and give up a ton of midrange. Here is the link to a program I made the HP # seems a little low I got it from RC Engineering, the rest of the air flow stuff should be dead on they are from my thermodynamics text book. This will get you ball park and show you what's going on, only dyno and road time can show you the absolute best turbo for your application. http://www.geocities.com/MotorCity/Shop/1553/trbcalc/turbocalc.xls If press F11 and double click on module you can view the formulas I used. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted April 10, 2002 Share Posted April 10, 2002 Thanks for the responses guys.. Scottie I've studied your zxt setup quite well, being that mine aught to be quite similar. This ZX is my daily driver, I'm going for supreme streetable performance, but I don't mind cutting low-end corners for midrange and top end. I'll see the tracks every once in a while, and I'd like to be well into the 12's. This is in a '79 zx, somewhere around a late 280z weighed, but less than later zx models (not much power stuff). I'll get rid of as much weight as I can. I'm not going to go so far as to repanel the entire body in fiberglass, but if I can get some door skins and a lighter hood, corbeau seats, I could probably keep it around 2800 lbs with to cope with the added weight of the intercooler, turbo, and r200 rearend. According to a few ET calculators.. controversy spared.. with 300 rwhp supposedly I would run around 12.8 @105 hp. Scottie I've had trouble finding your best run with your zxt setup. I realize you've got about 400 lbs less than me, but just for the fun of it.. what spec t3/t04 did you use? And did you ever have it dynoed? The whole water injection Idea would have been a last resort, before I could afford forged pistons and beefier bottom end. For now I will probably be okay using octane booster if I ever try to max out my setup. I really am not too concerned with the stock pistons.. 350 bhp is my goal, whether they can take that much, I guess we'll see On the subject of big spearco's, do you guys think the 2-205 core could fit up front? dimensions: 13"w, 24"h, 3.5"d I know the length (24") will fit, but with the added end tanks it will probably sit at least 17" high, and I've only got measured under there about 16"- with hood clearance. I had to remount my oil cooler because it didn't clear the hood, and sat well under the top of the rad. I suppose if I had to I could cut out the valence panels to mount it lower, but that still wouldn't spare me much room. The reason I like that intercooler best is because 1)its BIG 2)flow chart rates it well for almost all situations 3)with its flexibility, and flow capabilities, it would have high re-use/resale value. They do rate it from 1.2-8.5L btw . I'd like to think that any FI systems I built would be within that displacement range Okay, as far as the A/R goes.. with the t3 turbine section, I figured I could swap housings/wheels to get myself where I wanted. I have a sorce in socal (hah, I sound like a total riceboy ).. anyway, I can get t3 stuff pretty cheap. So long as I'm not losing any power at 5000 rpms, I'd be happy with a lower a/r. I really can't test my a/r data.. I'd just have tune once I got my system setup. I was just going by corky's suggestion from max boost. Clint I'd like to see your data but for some reason I can't pull it from geocities. Could you email it to me? oddenfam@msn.com I also have a nice excel turbo calc submitted by BLKMGK a while ago, I always run that one when I have a new set of numbers. As soon as I do have my setup of course I'll do all sorts of flow and efficiency tests, but once the money's spent... I'd rather take my best guess. So from what I gather from opinion, a 57 trim would take me where I want to be, I'm satisfied! If you will have an SDS F, big Spearco and only shooting for 300rwhp, you certainly do not need anything bigger than a t3/t04. With those components, you will make 300rwhp w/o even trying. My buddy has gone 11.74 @ 119 with the same setup at 19psi in a 240Z and that equates to about 350rwhp. !Sounds like the only thing holding me back now will be the pistons! Well, thanks for the info folks! Now all I need is about $3000 to buy all that stuff I discussed.. -980mak Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted April 11, 2002 Share Posted April 11, 2002 As I reflect on my L28ET setup, I kick myself in the butt for not running drag radials. No matter what lauch technique I tried, I would fry the tires of the line and put the car sideways on the 1-2 and could never get a 60' better than 2.0x. The car would recover and scream in the 2nd 1/8-mile gaining a best of 27mph between the 1/8 and 1/4 (you drag racers, compare that to other timeslips) and a best MPH of 110.97 but run only 13.0. The problem of course was the quick spoolup of the OEM t3. When I switched to the t3/t04, I only ran the car once. I do not know the specs of the turbo as it was slightly, ahem, WARM , and I did not look a gift horse in the mouth. IOW, I got it for almost nothing. It obviously did not have the Nissan OEM turbine components because the car lauched with less dramatics and with no practice clicked off a 1.74 60' and a 12.7 @ 105, yep 105 (??). Found out later my OEM fuel pump connections were badly corroded and I was not getting enough fuel on top-end. It was a tired junkyard engine that was on its last legs and I had already made the decision to swap engines. Quote Link to comment Share on other sites More sharing options...
clint78z Posted April 11, 2002 Share Posted April 11, 2002 You don't find many deals like that Scottie, you must have had to pick that sucker up with welding mitts I always like passing on deals I find , the only other one I found was Mike's Gnose for a low low price . Drag radials would have kicked booty, definately would have been intresting how far the old mill would have done given a bit more time. I guess it's up to the rest of us to continue to legend of the L28 Quote Link to comment Share on other sites More sharing options...
Guest Tim78zt Posted April 11, 2002 Share Posted April 11, 2002 Hi 980! Since it sounds like you are open to Corky's advice you might also give him a call about his intercooler recommendation. I'm VERY happy with the one I got from him. You can see it by searching my name in this forum. I posted my install a while back. Also if you are looking to make big power over 5000rpm you might want to look at cam options. My stock turbo cam seems to run out of breath at 4800rpm. Those options have been outlined in this forum in the recent past too. Have fun with your project!! Oh, BTW, I run the to4b Super H and it is awesome. I love that fast spoolup!! Different strokes, I guess!! Tim78zt Quote Link to comment Share on other sites More sharing options...
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