godzeerah Posted October 31, 2014 Share Posted October 31, 2014 Hey guys, Just poking around on the old interwebs and thought I'd try to compare my motor to others with one like mine as far as hp and torque numbers are concerned. I recently dyno'd my motor and got laughed at because the numbers were not what I was expecting. (Although the "Butt Dyno" seems to stop the laughing). It is quick, but I want a little more. I have a f54 with n/a flattops and a mn47 head. There's been nothing done to the head, only a "lower" lift and "higher" duration camshaft. I've got a 75 non egr intake and a 240sx throttle body with custom charge piping. Also, there's a set of msa 6-1 headers and 2.5 through a glasspack straight pipe exhaust. As far as tuning, I did the z31 turbo conversion with a z32 maf and a Moates Ostrich to change the spark and fuel to whatever I desire. 150 HP and 152 Lb Ft Torque at around 2000 feet asl. Looking around I've seen much more done to this setup and yield less power. I want more out of this **** thing, and might go turbo. Of course that would mean a p79 head most likely. What I want to know is that because if guys are porting their heads and intakes, why aren't they getting the numbers that I do (I saw several examples of 145HP)?...as far as I've seen so far anyway...and would it be worth it even for me to do the same? Seems to me that with the right cam/tuning, porting is worthless and a waste of time and money. Somebody chime in that's had some sort of experience with this head. I'm really looking for 200 range, and I don't think I'll get it. Has anyone gotten this before on this setup? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted November 1, 2014 Share Posted November 1, 2014 No experience with that head, but you should check out zredbaron's porting thread. Has a funny title like "No holds barred, max hp head porting" or something like that. He used an E31 and had 165 whp or something like that out of a stroker motor. Then he worked the head and redid the bottom end and ended up at 265whp or thereabouts. You can get the gist of what it takes out of that thread. Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 BTW, thanks for the input JMort, much appreciated, Ill check it out. Quote Link to comment Share on other sites More sharing options...
Akira Posted November 1, 2014 Share Posted November 1, 2014 http://forums.hybridz.org/topic/24798-na-31lhead-camshaft-questions-no-shortcuts-max/ Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 ...and thanks Akira for the link, I'll look it over...hopefully learn something. 1 Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 1, 2014 Share Posted November 1, 2014 I had people with headers, TB, chrome and bling swear at me because my stock Z whipped ther modded one by a full second EVERY TIME we ran the 1/4 mile. It's variability and attention to detail, 150 is about where a properly tuned stock L28 should be, it's where mine is, and the 1/4 mile times confirm the Dyno slip (if anything they make the Dyno low Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 As far as "stock z", I know the stock hp was around 150, but shouldn't this motor of mine maybe deliver a little more since it is 11.2:1 comp with a cam and more modern fuel injection...or is the air intake really that restricted? Do I have a lot of potential just sitting there and I'm just an "idiot" for not trying to pry it out? BTW I have methanol injection too. Or perhaps that dyno is off....I did run a 14 sec flat 1/4 mile with a 78 z. All the calculators say that's around 200whp with my weight. Quote Link to comment Share on other sites More sharing options...
johnc Posted November 1, 2014 Share Posted November 1, 2014 Tomato, tomaahto. I cleaned up the misunderstanding. Quote Link to comment Share on other sites More sharing options...
madkaw Posted November 1, 2014 Share Posted November 1, 2014 How aggressive is your timing with that CR? Did you do any tuning while on the dyno? Were your O2 reading good? Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 I'll have to check my timing map to make sure what I am at with total timing. Base timing is set at 18BTDC to smooth out the cam idle. I know the top end isn't too advanced to get detonation. As far as AF/R's, my brand new AEM wideband says I'm at 12.9:1 during hard acceleration, but the dyno says 13.8:1. I think mine is right because I backfire during decel pretty loudly sometimes, which usually means the mixture is so rich it is continuing to burn in the exhaust. \ I forgot to mention that she has developed a miss fire above 6K. I usually rev to a bit below 7K, but ever since the dyno I haven't been able to get that high....this concerns me because the dyno seemed to have put excessive load on the motor. No, I did not do any tuning on the dyno. The dyno I used was at my tech school I'm currently in, and I didn't have the time to actually tune it on the dyno. All my tuning was done in seat on a bare country road....and no I didn't speed Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 1, 2014 Share Posted November 1, 2014 My car runs consistent 15.50's at 89.... A 14.0 at higher trap speed would tend to indicate more torque and therefore more horsepower. Dyno numbers, unless strictly defined are pretty much useless one to another. Stick with the same Dyno for relative performance quantification change. A stock 76/77 Coupe will run (as evidenced by my foul-mouthed companion...) 16:47 or slightly slower in the real world. Mine was quicker by a full second, and you're a good 1.5 faster than me... I know I've been on three different metered quantifiers, A G-Tech, A Dynojet, and A Mustang traceable to SAE J Whatever it is... And they all come in within 20 (+\- 10 HP of median) and they all correlate to the 1/4 mile trap speed and weight as tested the day of the runs, on the return road of the track. Dyno testing isn't IR the faint of heart, fact of the matter is if it won't pull on the Dyno it's not making power regardless of what it feels like. My biggest help in getting good shift points was using an old G-Tech on "Instant G's" that tells you how hard the car is REALLY pulling. Regardless if it's sounding better, if the G's drop, you're loosing time! Unlike Obiwan, my post death haunting will be "Use your Instruments, Quote Link to comment Share on other sites More sharing options...
madkaw Posted November 1, 2014 Share Posted November 1, 2014 Total timing is more important than the fact that you upped your CR. Your 12.9 AFR would not be rich enough to induce backfire so maybe you ARE running a bit lean up top. Might have some tuning to do yet to yeild best results . Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 (edited) So, 12.9 is lean...ok i'll check it out. I'll see if I can advance my total timing and just dump fuel in on hard acceleration. It could be needing more advancement to get it through the sputtering at 6k. Let me see if I can't get a pic of the dyno sheet put up here. Also, I know total timing will affect exhaust temps, which I'm also considerably high at WOT I think at 650-700 degrees Celsius. So maybe my total advance is ok, just needs more fuel...I'll go look today and see what the number actually is. Yes, my high torque number was 152, but the band was flat from 3k to 6k untill it started sputtering.... Thanks for all the input! Edited November 1, 2014 by godzeerah Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 OK, so I checked my timing...I'm at 22 degrees at 4500, 25 degrees at 5000, and 27 degrees at 5500. Anything above that stays at 27 degrees... Quote Link to comment Share on other sites More sharing options...
Xnke Posted November 1, 2014 Share Posted November 1, 2014 Which is probably all you can run before hitting detonation, but it is worth the effort to fix that distributor. I would call around and see if there are any dyno shops around who can re-curve a stock distributor. I would want to see 18 degrees at idle, to 1200RPM, then ramp all the advance in by 3000RPM, shooting for 28-30 degrees total advance. You don't really need that last 6 degrees or so with the very closed chamber head when running a flat-topped piston. That assumes though, that you have flat topped pistons, and 11.25ish to 1 compression... What camshaft profile are you running? lift, seat duration, duration at 0.050" lift, IO/IC/EO/EC? Quote Link to comment Share on other sites More sharing options...
godzeerah Posted November 1, 2014 Author Share Posted November 1, 2014 (edited) Here are some pictures of my cam card and the dyno run...the cam is custom. Sorry about the card being dirty, I spilled coffee on it and cussed like you wouldn't believe. The lift is 432ish at 1.5 to 1 rocker ratio and duration is at 264*. As far as the distributor...I have a CAS style distributor from a 280zx turbo with a 300zx wheel in it. Like I said I can control my timing to anything I want through my emulator at the EEPROM. And yes I have flattops Edited November 2, 2014 by godzeerah Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 2, 2014 Share Posted November 2, 2014 I would call your cam grinder and VERIFY that the cam card is not a simple typo...otherwise.... The Rocker Arm Ratio on a Nissan L-Series is 1.5 (1.48, meh) and NOT 1.00! If they REALLY DID MEAN "1.00" then the cam is going to act significantly different at 1.5 ratio. After Peak-Torque you pull fuel. On JeffP's turbo engine we were pulling fuel after peak torque and stopped at 13.8 AFR simply because we were seeing minimal increases in HP, no change in EGT, and didn't feel the need to push it further. We started at the Paradigm of 11:1 for turbos, passed thorough the Paradigm for N/A, and didn't see the need to go,further as stated above. Prior to that time, had you told me a 400 hp turbocharged engine under boost would run at 13.8:1 AFR at 7,000 rpms I would never have believed it, much less one making half again as much HP! Quote Link to comment Share on other sites More sharing options...
Xnke Posted November 2, 2014 Share Posted November 2, 2014 (edited) It is a typo...I back-checked the indicated lobe lift vs the rocker ratio, the lobe lift given is 0.288", he says he measured about 0.432" lift at the valve, that's a 1.5:1 ratio. That cam grind looks a little odd, but the cam is "very small". The lift numbers are pretty much spot on for a stock, unported head, although I would want more duration at 0.050" lift. Somewhere around 224* at 0.050" lift for a 0.430" lift cam. I would not look for more than 180HP, really...but given that you have a presumably un-ported, small-valve Maxima N47 head, 154HP and 150ft-lbs is pretty respectable! Edited November 2, 2014 by Xnke Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 2, 2014 Share Posted November 2, 2014 Yeah, the numbers looked right to me but that card freaked me out. VW grinders do that all the time sending you a 1.00 gringos what you specified a 1.25, 1.5, or 1.7 rocker grind (ramp rate varies greatly...) I think looking at the guys from OZ on that small port head would net an equivalent combo. Quote Link to comment Share on other sites More sharing options...
madkaw Posted November 2, 2014 Share Posted November 2, 2014 I didn't mean 12.9 was lean, but the dyno measure of 13.9 is another story. As far as timing, my l24 showed no significant gain from 33 total and 37 total. With an efficient chamber like the MN47 you might not need much more timing, but get all you can! Didn't the mn47 have the smaller intake valve too? Did you just install cam straight up or did you verify numbers with degree wheel? Quote Link to comment Share on other sites More sharing options...
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