Dan Baldwin Posted June 23, 2003 Share Posted June 23, 2003 I went to New England Dyno on Saturday, with my rebuilt 3.1 liter. Results were, to say the least, beyond my expectations. Based on the small displacement bump and increased compression ratio, I expected at most an increase from 235rwhp to 245. Current setup is: 89.5mm bore/83mm stroke, 3133cc (up from 3098cc) 11.1:1 calculated/10.8:1 measured-volume CR (up from 10.74:1 calculated) N42 head with cam setup, porting, and modest cc reshape by Sunbelt 3x2 45mm OER Racing carbs My 280Z magnetic pickup distributor failed on Friday afternoon, so I had to put my 240Z dizzy and points (new/unused) in. Worked fine up to 6250rpm, beyond that points bounce pretty much ended the runs. Fortunately peak power looks to be right around 6250, but there may be a couple of additional ponies up there! After doing a few runs on pump gas, playing with jetting and then timing, I did three runs on VP C11 fuel (104 motor octane, ~107 (R+M)/2?). These runs were well below the runs on pump gas, with maximum hp made with about 4 degrees more advance compared with the pump-gas runs. What this tells me (other opinions welcome) is that my "detonation-prone" open-chambered N42 has no issues running on 93-octane pump, at close to 11:1 CR. The mixture curve (and, consequently, the torque/power curves) are a bit of a roller-coaster, going from 13:1 at 3000 to 10.25:1 at 4500 to 13.3:1 at 6300. Yuck. I still have carburetion issues below 3000, I had to ease on the throttle to keep it from bucking too badly beginning the runs. 1: 251.8 (165 main, 200 air jets; ~15 initial/34 max advance) 2: 254.8 (160 main, 190 air jets; ~15 initial/34 max advance) 3: 253.0 (165 main, 190 air jets; ~15 initial/34 max advance) 4: 241.6 (165 main, 190 air jets; ~19 initial/38 max advance) 5: no data 6: 245.2 (165 main, 190 air jets; ~11 initial/31 max advance) 7: 237.1 (VP C11; 165 main, 190 air jets; ~15 initial/34 max advance) 8: 243.0 (VP C11; 165 main, 190 air jets; ~19 initial/38 max advance) 9: 237.0 (VP C11; 165 main, 190 air jets; ~23 initial/41 max advance) Whaddya think?! Quote Link to comment Share on other sites More sharing options...
yo2001 Posted June 23, 2003 Share Posted June 23, 2003 that is stout sir Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted June 23, 2003 Share Posted June 23, 2003 Smoking! Great stuff Dan! Enjoy Quote Link to comment Share on other sites More sharing options...
johnc Posted June 23, 2003 Share Posted June 23, 2003 Should be a monster... And that's on street gas. Try some leaded 100 octane and see what she'll do. Quote Link to comment Share on other sites More sharing options...
Dave240Z Posted June 23, 2003 Share Posted June 23, 2003 Wooohooo, another n/a triple carb'd L6. Those are some decent numbers you have there and with a little more tuning (and a new ignition system) you'll be in good shape. 255rwhp with a bad ignition and wacky fuel ratios out of a stroked and carb'd L6 is very respectable. Quote Link to comment Share on other sites More sharing options...
katman Posted June 23, 2003 Share Posted June 23, 2003 Hey Danno: Email me a new dyno chart. You still got that hole at 4300? Glad to see you back on the road. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 23, 2003 Share Posted June 23, 2003 Should be a monster... And that's on street gas. Try some leaded 100 octane and see what she'll do. He did - and it didn't work as well. Nice numbers, Dan. I've been of the opinion that the N42's supposed detonation problem was bs for quite some time, too. Glad to see someone else out there disproving the myths. Quote Link to comment Share on other sites More sharing options...
z-ya Posted June 23, 2003 Share Posted June 23, 2003 Hey Dan, Awesome numbers!! Post the plots when you get them. I'm dying to see you run with the new motor. Time for better brakes?? Are you doing the August COMSCC event? I plan on doing at least the school, and possibly the next day if I get the OK to solo. I hope to get my car back to New England Dyno soon to tune in the new turbo. What are they charging this year per hour? Did to pay extra for the "expert" next door? I really like them over there. They let you drive, and they were very reasonable. I also like dynos that are in the floor. Later, Pete Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted June 23, 2003 Share Posted June 23, 2003 Nice numbers, a P79 would have done better. J/K HAHA, I just had to throw that out there. Quote Link to comment Share on other sites More sharing options...
Guest norm[T12SDSUD] Posted June 23, 2003 Share Posted June 23, 2003 You RAWK Dan!! Now get some slicks and take that beast to the track!! I'd predict low 12's with speeds above 112 mph with some aggressive driving!! BTW, I know where you can find a very aggressive driver !! hehehe later Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted June 24, 2003 Share Posted June 24, 2003 Outstanding numbers!!! I would like to see you make a few passes on the drag strip as well. Ya' know, Just for grins!!! Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted June 24, 2003 Share Posted June 24, 2003 Well done, Dan. Quote Link to comment Share on other sites More sharing options...
Mike C Posted June 24, 2003 Share Posted June 24, 2003 That's awesome Dan! Can't wait to see the numbers after you get ignition and carb issues straightened out. Quote Link to comment Share on other sites More sharing options...
Guest DaneL24 Posted June 25, 2003 Share Posted June 25, 2003 What kind of trans and diff are you using? Get a Borg Warner T5 and 4.11 gears in a 2300 lb 240Z with 255 RWHP...the ultimate NA L6 monster. See ya later 12 second quarter mile barrier...hello 11's. Quote Link to comment Share on other sites More sharing options...
Dan Baldwin Posted June 25, 2003 Author Share Posted June 25, 2003 Thanks for the kind words! In reverse order, I've got a stock (LOW breakaway) 3.70 LSD, and a newly installed rebuilt '84 truck 5-speed. This is likely the best stock Nissan 5-speed for roadracing: 3.321, 1.902, 1.308, 0.833. Man I'm glad to be rid of the super-tall ZX 5th gear! I don't see myself in the 11s anytime soon, btw. My main interest in going to the drags would be to see what kind of trap speed I could get. I'm too much of a candy-ass shifter to be really quick, I'm afraid. Not to mention I've no idea how to launch. Norm, running the numbers, I guess I should be good for at least 110, but I don't know if I believe it! Guess I'll have to make a trip to NEDragway soon. I don't see low 12s with me behind the wheel. Maybe mid-13s. Let me know if you're ever in New England and maybe we'll see what you can do with it (just don't BREAK it!) Pete, I think I'm sort of a wuss on brakes as well. BobH certainly was underwhelmed at VIR! Maybe next year... I plan on doing all the NHIS COM events, plus the Glen and Lime Rock. Hope to see you solo there. I spend $170 for an hour and a half at the dyno. I think the rate is $150/hour with A/F. Pretty steep compared to $40 for the bike here in New Bedford. Didn't know you could pay extree for an expert, but I don't think they have a 3x2 carb expert anyway. I like 'em there, too. Should be getting data files from them soon, will post. More (plots) to come! Quote Link to comment Share on other sites More sharing options...
Guest DaneL24 Posted June 27, 2003 Share Posted June 27, 2003 You have the HP and TQ necessary for a fast quarter mile, you would just need the gearing for a quarter mile dash. Even Electromotive's 300 HP NA 280ZX was only running high 13's/low 14's in the quarter because of its gearing. Thats what I meant when I said your car might break the 12's...with the right gears. If your primary use for the car is road racing though...there isn't really much to discuss. Quote Link to comment Share on other sites More sharing options...
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