Drax240z Posted June 23, 2003 Share Posted June 23, 2003 Ok, I blame myself for this as mine was the first reply to David Karey's suggestion that he wanted a sequential EFI system for his car, and I suspect I set a bad tone for the thread. Anyway, if you wish to seriously continue discussion on this topic, please continue here and keep it civil. ------------------- Origional Post: ------------------- Ive decided to run this setup as i now have all the parts. F54 block flat pistons P90A with P79 solid lifters, shaved .08, shimmed .08 TWM throttle body Stock cam Now, did yall know that we may be able to use the Infiniti M30 fuel injection system? The M30 is the convertible that used the vg30. Its sequential, and not batch fire. If we are able to figure out what the pulse order is for the injectors, we may be able to run sequential injection on our inline 6's. Anyone know more about the M30 f/i system? - David Karey ------------------------------------------------------------ Quote Link to comment Share on other sites More sharing options...
David K Posted June 23, 2003 Share Posted June 23, 2003 Ive just got off the telephone with an gentleman who has run a Z32 harness and they also were looking into the m30 system, and it for sure can be run with a JWT ecu. Sequential is what the top guys want, not batch. Quote Link to comment Share on other sites More sharing options...
Bernardd Posted June 24, 2003 Share Posted June 24, 2003 What are the goals for the M30 ecu? Besides being sequential, are you going big hp turbo, NA, bling bling??? Are you going to pay JWT to reprogram? Is it a cost is no object thing? Are you expecting to install it and the car to run perfectly? Just wondering. Personally I would use the z32 ecu. It's sequential as well and eeeezzzy to work with. You can even get a realtime datalogger, maptrace and editor all in one for the z32. Anyway it would be cool if you could get it to work. Bernard Quote Link to comment Share on other sites More sharing options...
David K Posted June 24, 2003 Share Posted June 24, 2003 Bernardd, i did thank you for your reply in the other thread. I am going for a more efficiant engine system without going aftermarket. Im learning about mid 90's Maximas, M30's, and Z32 systems and researching all before i get started on the hands on part. I may be picking up a complete M30 system this mid-week, so i am going to go over it and see what i can learn by it being out of a vehicle. Also, i have a buddy that is the manager of parts dept at a local nissan dealer that works their fair share of performance cars, and believe it or not, they are also a large aftermarket supplier for Nismo and many other popular companies. He is going to send me over the complete mechanic wiring diagrams and diagnosis information for the Maxima, m30, and z32, sometime this week. Im also going to go over those thoroughly and learn how they work. Im on a few other leads as well. Ill keep everybody who is interested in my project posted on my research, failures, and success. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 24, 2003 Share Posted June 24, 2003 What are the goals for the M30 ecu? Besides being sequential, are you going big hp turbo, NA, bling bling??? These are very good questions. It was mentioned that "all the top guys" want sequential - I'm not sure that this is true. What is the expected gain? In general, sequential is helpful for smoothing out idle and improving emmisions at moderate (i.e. part throttle) output levels. I don't think that you'll see any power gains from such a setup at all. This is not to say that smooth idle and emmisions are not important, just trying to keep expectations realistic. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted June 24, 2003 Share Posted June 24, 2003 Maybe this isn't what you want to discuss on this thread, but since your asking about batch vs sequential.... Everything I have read comparing the two shows that from mid rpm up they perform the same. At lower rpm and idle the sequential has the edge because it delivers the fuel at the time it is needed, not letting it pile up at the back of the valve like batch(I suppose this helps atomization because as the valve is opening the air is more turbulent and the sequential only sprays at this time?). Once a certain rpm is reached the piling up of fuel doesn't matter because the time between opening valves is very small. For all practical purposes the valve is opening so fast and the injector duty cycle is so high, the sequential and batch perform the same. Quote Link to comment Share on other sites More sharing options...
David K Posted June 25, 2003 Share Posted June 25, 2003 Moby, thats exactly what im going for. Its gotta be all around better performance, Even if they perform the same at high rpm's, the sequential still knocks batch out of the water. Also, have you guys ever heard of a guy just wanting to be different? 8) Here are 2 pics of my TWM. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted June 25, 2003 Share Posted June 25, 2003 Moby, thats exactly what im going for. Its gotta be all around better performance, Even if they perform the same at high rpm's, the sequential still knocks batch out of the water. Also, have you guys ever heard of a guy just wanting to be different? 8) How does sequential "knock the batch out of the water"? Can you quantify that statement? Quote Link to comment Share on other sites More sharing options...
Mike C Posted June 25, 2003 Share Posted June 25, 2003 From the research I had done in the past, ALL of the sequential FI setups revert to batch fire above 3000 rpm. Just like an MSD which IS multispark at idle-3000, but single spark after that. The time limit you are working at is too short for the multi-spark or the SFI to be functional. SMPFI is for best low speed drivability and throttle response but won't net you any more power above 3000 rpm. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 25, 2003 Share Posted June 25, 2003 The time limit you are working at is too short for the multi-spark or the SFI to be functional. SMPFI is for best low speed drivability and throttle response but won't net you any more power above 3000 rpm. The time limit isn't really the issue, at least not in the way you appear to be thinking. Assuming batch mode is still synced to the engine events, 80% duty cycle is still 80% duty cycle, regardless of how the individual injectors are phased to each other. The issue is that the intake valve runs at a fixed duty cycle of somewhere around 35% (assume ~250 degrees open out of 720 degrees of rotation). So, once you get appreciably above a 35% injector duty cycle (i.e. more than part throttle, low rpm), the injector is going to be firing on a closed valve for a good part of the time no matter what you do. The higher your injector duty cycle gets, the less difference sequential makes. In fact, once you get above ~70% duty cycle, you are more likely to be firing on a closed valve than not, regardless of how you phase the injector. David - not trying to rain on your parade, but you original post made it sound like you were assuming sequential was going unlock some sort of power secret (you wouldn't be the first person who thought that). It is helpful for part throttle low rpm response and it can make a noticeable difference there, but I really think it's greatest value is when you are an oem that has to pass emmisions tests. Like I said, just trying to keep expectations realistic. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted June 25, 2003 Share Posted June 25, 2003 I just wanted to make sure my info was in line with other peoples, and it sounds like it is. If you want to run sequential it will be good for the group to have another different setup. Let us know if you get it running that way Quote Link to comment Share on other sites More sharing options...
johnc Posted June 25, 2003 Share Posted June 25, 2003 Wonder why nobody is thinking about CIS? There are tons of KE-Jetronic systems out there on Mercedes 6 cylinder vehicles from the 1990s and they are simple, trouble free, and relatively cheap. You can find very sophisticated untis (like KE3 and KE5) on the 300SLs of the 1990s. Almost any CIS system has about a 50% reserve capacity built in. That means you can increase air flow through the engine 50% and the stock system will deliver the correct amount of fuel. Hot rod Golfs normally run the stock KE-Jetronic system until the get over about 170 horsepower. Porsche ran the stock KE-Jetronic system from their Turbo engines on the 956 GTP cars. When they went to the 962 they just added a complete, second stock system and the dual setup metered correctly. Quote Link to comment Share on other sites More sharing options...
jeffp Posted June 25, 2003 Share Posted June 25, 2003 first off the thing that stands out in my mind regarding the sequential system and why it would be a better setup is that like most of you said it fires one injector at the correct time. This is a distint advantage when you stop to consider that all of the fuel, junk that is back washed theroug the port tends to land on the back side of the valve. Not a big problem, except that it will build up over time and you will lose power because the flow characteristics will change. For me that is a significant consideration. The second thing that I would like to find out more about is the potiential of the system in the way of max hp it is able to develop. I could Give JWT a call and find out what kind of power they are able to get from the unit. I do know that they seem to have hit a challenge getting the Z31 ECU to make power ovwer 500hp. I am not saying it is impossible, but it does require some circuit modifications in the MAF metering to do it. Also, since we are here in CA and our cars are technically susposed to be tampered with for smog reasons, would it be cool to have a 600Hp car that passed CA smog for that particular car. We would know it has a different fuel management system, but on one else would and the car could be certified by the DMV as passing the smog guide lines fot that car. So in my mind that is also deseriable. Who cares if you have a car and EGR if you are turning the power you want from the engine, and I am convenced that is possible with the correct setup and combination of parts on the car. So that is what is floating around in my head. Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 25, 2003 Share Posted June 25, 2003 ...Not a big problem, except that it will build up over time and you will lose power because the flow characteristics will change. For me that is a significant consideration. Maybe, but I'm not convinced that there is a correlation there. On a batch fired system, at least one of the cylinders is phased properly (possibly two if it fires every 360 degrees instead of every 720). So if this were true you would expect that batch fired engines would have valve deposit problems on all but one (possibly two) cylinders. While I have not researched it, I have never heard of this being true. I mean come on - it's not like anybody is truly expecting their 600hp L series motor to go without maintenance for the number of miles required to get this kind of deposit buildup anyway. The second thing that I would like to find out more about is the potiential of the system in the way of max hp it is able to develop. I could Give JWT a call and find out what kind of power they are able to get from the unit. Still contending that sequential won't do didly for max power - it's not logical to expect it to. Quote Link to comment Share on other sites More sharing options...
Bernardd Posted June 25, 2003 Share Posted June 25, 2003 David: Have you considered an rb20det ecu, sensors etc? It is fully hacked, bordering on GMECM flexibility. The ecu and harness are readily available from Australia,and the wiring diagrams are available on the net. I think that all the Nissan coilpack management systems use dummy coilpacks. By that I mean they don't have any dwell calc's other than what the ecu does. If you use a coilpack for a different engine it would be as simple as using the dwell table for that particular ecu/coilpack and away you go. You may even be able to use a single coil on a multicoil setup by altering the dwell table. I was planning on going this way but changed my mind when I was able to use the vg30et ecu to run my 370cc injectors. Another question I have is are you going to tune this yourself? Or pay JWT for a custom setup? Personally I'd rather have a carb than go JWT but I'm kinda weird about being talked down to. It's very doable but a lot of work for no gains that I can see. If you want info any of the other ecu's let me know I have piles of info. Quote Link to comment Share on other sites More sharing options...
turbobluestreak Posted June 26, 2003 Share Posted June 26, 2003 I personally like this idea of converting to a RB20DET ECU because I'm still pondering on setting up a RB20 head on the L28 block all that I need to check on is a oil pump and if it looks good I'll be looking for a head to import and mess with. I should know by this weekend if the oil pump works out. I would like to keep from using a dry sump for this applcation to make this idea more theaseable for other L6 driven z cars. Sorry to steal you post just need to get this out. tbs Quote Link to comment Share on other sites More sharing options...
David K Posted June 30, 2003 Share Posted June 30, 2003 I putting the m30 idea on the shelf until funds are availble. The cheapest m30 system i found was over $500. They are next to impossible to find in the junkyards also. Ill be doing a complete write up on installing z31 components into L28 f/i systems. Quote Link to comment Share on other sites More sharing options...
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