Guest BigWhyteDude Posted November 9, 2003 Share Posted November 9, 2003 wow thats one fast pocket rocket. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted November 9, 2003 Share Posted November 9, 2003 " Well' date=' lockjaw, is 313mph fast enough for a megasquirt powered vehicle, or how about 619Hp at 10,000 rpm on a Turbo Busa Motor? Take a look at: http://www.turborick.com Rick has successfully garnered several Land Speed records with his Megasquirt Fueled Turbo Busa Powered Streamliner. Going 313mph+ makes 12's look way weak. [/quote'] I think you miss the point. One guy with some turbo busa is not what i am talking about. We have people on this board with megasquirts, and they talk about them like they are the best thing since sliced bread, yet I don't see where they are running anything awe inspiring. So where are some Z people with them running 12's? How about 11's? That is why I poo poo'd the megasquirt comments. Lets see some people successfully install them and run some good times. Thats what I want to see. So where are they? Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted November 10, 2003 Share Posted November 10, 2003 WOW Bryan.....I would think that you would be happy just having a driveable car!!!! Are you sure that you really want to start squeezing evry ounce of power out of your daily driver?.....just wondering ROFL yeah I AM very happy to have it driveable, and that it's been running so well... it's been great TRUST ME!! And anyways money (lack thereof) dictates that I couldn't be in a rush to make tons of power even if I wanted to... and as far as getting every last ounce, I'll never ever get there. Unless I win the lotto, there will never be enough in my budget to go crazy cash-wise and do all the big buck mods like injectors, programmable EFI, better turbo... all the stuff that most people here have done. I've already set my limit and I"m sticking to it (or my g/f will have my head!). I really just want to get the most out of what I have right now (read: run the most boost that I can safely run and that is efficient)... which is pretty much bone stock everything. The only mods left on my to-do list really are installing the I/C I already have, and then installing something that will let me adjust the fuel flow to make it safe, and make it run as good as possible. Then eventually install a mandrel 3" exhaust... and then paint the darn thing and THAT'S IT!! REALLY! Come on though you can't really blame me for being eager to get some more power out of the thing... isn't that what turbos are about? I only keep posting questions like this to expand my knowledge... I spend lots of time going thru the archives and reading so much info regarding turbo Z's and turbo cars in general and so much of it is conflicting... I just want to get the facts straight. By the way my car just had the first problem in almost two weeks... sidelined my ass quick and had to get it towed home... and over something so seemingly stupid and small. The threads on the rod that comes out of the cluctch master cylinder, and bolts into the bracket attached to the back of the clutch pedal, stripped somehow and the rod popped out, leaving me with no clutch, I tried to just mickey mouse it back on but every time I'd shift it'd pop back off... the real killer is how hard it's been to find a rebuilt one to replace it with. I dont really need a whole rebuilt unit, the cylinder itself seems fine, and luckily, I found that I had an old master cylinder in a pile of old parts I keep... I know the cylinder itself is no good but I can use the threaded rod from that one. I'm also noticing the fuel pump is starting to get noisier, I dont expect it will last much longer, and I've noticed a few coolant leaks on some of the smaller coolant lines, which I will take care of today when I reinstall the clutch cylinder. Then there's the issue of exhaust smell in the car, which had all but dissapeared when I installed a new downpipe gasket, but has been steadily getting worse over the last few days.... but still... I AM so loving being able to drive it at least! Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 10, 2003 Share Posted November 10, 2003 to run decent times with the MS you need about $200 and about an hour of tuning. This is why anyone with one talks raves about it. I suspect many people who have paid 5 to 10X that for the processor alone just have heartburn that they possibly overbought. Good times with a Z are somewhat more a function of tires and setup than a complex Fuel Delivery Scheme. A case in point would be Norm's 12.90's on SU's. For the PRICE, the MS is VERY hard to beat. Have you ever gone to the MS board and looked at the "it runs" listing. There are plenty of them out there worldwide. Most who use them are more interested in getting a driving running vehicle day to day, than boasting about their numbers. And Rick's Turbo Busa motor is in a Streamliner, not a bike. And 313mph is a bit more impressive to me than quarter mile performance. You can run 12.50 on a Crown Kit and a Holley four bbl in a 240 all day long---that in itself is not really all that hard to do. Richard's Z/ZX service had a low 11 second car with that setup in 1980. Anyway, I can think of at least a dozen Z'ers who have this setup, and who are very low-key. I am currently debating wether I will use MS (since Rick's Success at Bonneville) on my S130 Bonneville car, or wether I should buck-up for something a damsite more expensive, for the simple addition of spark mapping. Quote Link to comment Share on other sites More sharing options...
Sean73 Posted November 10, 2003 Share Posted November 10, 2003 Okay Tony' date=' so it IS the EFI system, in FULLY stock form, that limits power at anything above 10psi, due to the way the ECU is programmed? Or is it the limitation of the fuel pump as Sleeper suggests?... Now I'm back to wondering though... if I had to choose ONLY ONE method of increasing top end fuel up to the limit of the stock injectors, and this is assuming I have already upgraded the fuel pump... then which would be the better choice TO START WITH, an RRFPR or a programmable unit like the HKS? [/quote'] Bastaad - To calculate HP from injector flow, I use this equation from Maximum Boost: pounds of fuel per hour per injector=(expected bhp x .55)/number of injectors I believe stock ZXT injectors are 270cc, or 25.71 lbs Re-arranging the equation and solving for HP yields 280.5 HP @ 100% duty cycle, or 252 crank HP @ 90% duty cycle. So, the injector-imposed limit of your fuel system is 252 crank HP, not RWHP. The ECU is limiting duty cycle at ~90% (probably for some safety reason). The limit is even lower if your injectors are old, dirty or worn out, or if other EFI itemes are not up to par. 252 crank HP equates to roughly 8-9 psi in a perfect world at sea level. But, due to the Ideal Gas Law, you lose charge density (and HP) by compressing gasses. So, it's not hard to imagine leaning out at 10 psi, especially with a cheapo intercooler (or no intercooler at all) and stock T3. Given these limitations, I am not suprised by Tyson's dyno that you mentioned. Like Tony said, with tweaks, all bets are off. Based on your question you have two choices for you fuel system: 1) extend the duty cycle further (not much room for that). 2) increase fuel pressure to increase fuel flow. The former could be accomplished with the S-AFR, the latter accomplished with an adjustable FPR or RRFPR. Increasing fuel pressure is easy enough, but has limitations. For one, flow is proportional to the square of pressure. So, for example, I think Sleeper said he was running 44 psi, which is roughly 19% increase over stock. However, the resulting fuel flow is 9% over stock. Moreover, all of these figures are idealized. I assume you don't have restrictive exhaust or EFI problems that limit your power. You need a baseline dyno to see where you're at. I could not tell you to buy one part over the other (RRFRP vs. HKS). It's apples and oranges. Perhaps the HKS could get you 5% more duty cycle, or 5% more power. The RRFPR would definitely be able to deliver more fuel at the topend, but how much confidence do you have in your fuel rail to hold those high pressures? Tuning without a dyno would be a problem on both devices. I think the HKS would only be worth it if you upgraded the injectors. In any case, the proper way to deliver more fuel is with big injectors and ECU mods to accomodate them. Sean 73 240Z, L28ET, 84 ECCS, NPR, T3/T04E, 3" mandrel exhaust. (almost ready to run) Quote Link to comment Share on other sites More sharing options...
mobythevan Posted November 10, 2003 Share Posted November 10, 2003 That is why I poo poo'd the megasquirt comments. Lets see some people successfully install them and run some good times. Thats what I want to see. So where are they? Right here, same place I've always been. Doesn't seem like a fair comparison because once I have MS installed I will also have an intercooler in, 60mm TB, 450cc injectors, bigger fuel pump, running 14psi boost, new clutch that actually holds, MSD ignition. I guess your trying to gauge whether the average Joe can install MS and get it to work. That is a valid arguement, but as long as the person installing it has the know-how it will work. I can tell you what is the limiting factor on my car right now and it isn't the fuel system (clutch). I think with MS it all boils down to one thing, do you have the know-how for a DIY project, if not you better stick with HKS or something similar where they have someone with the know-how to help you. Boy, I hope no one is waiting on me to see how my install of MS goes because I must be the slowest person on this forum. But I will keep everyone updated. I might actuall install it this weekend if you can believe that!!!!!! BTW, when I say "you" I mean anyone, not you in particular. Don't want anyone to take offense to my posts. Quote Link to comment Share on other sites More sharing options...
Bernardd Posted November 10, 2003 Share Posted November 10, 2003 I ran the stock turbo with 370's and stock fuel pump for about 2 weeks. It became evident immediately that the stock pump isn't worth much. I couldn't get any more boost from the stock injectors versus the 370's. As soon as I changed the fuel pump I could ran 15psi with no problems at the top end. I didn't spend much time tuning the afm and switched to the z31 ecu with the stock injectors the next spring. In my case it was the fuel pump that was the problem. Tony D: You can control spark with megasquirt'n'spark. I'm waiting for someone who's already posted in this thread to get the spark part working. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted November 11, 2003 Share Posted November 11, 2003 Sean73 - very informative post, thank you Dyno time before AND after my next round of mods is a high priority on my list, to get a baseline and to tune it up RIGHT. Bernardd - that's Sleepers idea too... seems the stock fuel pump isjust not meant to support much more than stock. I have decided that upgrading that is my next mod for sure, after installing the intercooler, and before turning up the boost any further. Then most likely will come the HKS or other programmable unit (I'm still very heavily considering the Megasquirt myself) and then if I find fuel still running out at the top I'll get the RRFPR... after all the replies here this seems to be the most sensible order to go in. Quote Link to comment Share on other sites More sharing options...
yo2001 Posted November 11, 2003 Share Posted November 11, 2003 Good fuel pump does the trick. I run Autozone injectors and model unknow Walbro pump. The stock injector will sopport more than 250HP due to rising fuel pressure via boost. so 265 injector @ 36 psi will be 36psi plus 10 psi of boost under WOT. stock pressure and 10psi on Z31, mine went below 10:1 un certain spots on dyno. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted November 11, 2003 Share Posted November 11, 2003 Hey... if Tyson dynoed 191hp and 219ftlbs at the wheels with a 3 speed auto, how much would he have made if he was running a 5 speed? I'm still trying to get a good idea of what my car should be putting out now at 10psi... the only good reference point I have was Jersey, when he ran a 13.3 at 10psi with no intercooler, given that average weight of a 240 and just assuming his weight to be around 200 lbs, that put his car at about 210-220 at the wheels... the only real difference I found between his setup and my current setup was exhaust (his was 2.5" mandrel to my bastardized 3" & 2.5" press bent) and that he was running 93 octane to my 91. Quote Link to comment Share on other sites More sharing options...
yo2001 Posted November 11, 2003 Share Posted November 11, 2003 13.3 with 1.9 60ft. I think it was. 60ft is the key. You prollt making about 200RWHP. give and take 5RWHP Quote Link to comment Share on other sites More sharing options...
TimZ Posted November 11, 2003 Share Posted November 11, 2003 The stock injector will sopport more than 250HP due to rising fuel pressure via boost. so 265 injector @ 36 psi will be 36psi plus 10 psi of boost under WOT. The extra 10 psi of fuel pressure under boost only maintains the original 36 psi across the fuel injector (remember that the other side is at 10psi). This will allow it to have the same flow capacity, no more, no less. Quote Link to comment Share on other sites More sharing options...
yo2001 Posted November 11, 2003 Share Posted November 11, 2003 O, yeah. Then I don't know why my stock injectors flow much more than 250HP. Ran 253RWHP with stock injectors at 44psi. never went pass 12:1, and actually rich at 6000rpm. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted November 11, 2003 Share Posted November 11, 2003 1.8 60ft on street tires... would love to know how he pulled that off... I remeber watching the videos of his runs... friggin amazing launches with little or no wheelspin off the line, then he chirps 2nd 3rd and 4th gear with a more 'normal' launch I figure he'd be closer to the high 13's I estimate my car should run. Quote Link to comment Share on other sites More sharing options...
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