PhaTTy Posted March 2, 2003 Share Posted March 2, 2003 OK.. here goes I am going for the 3.1 buildup with injection. I am getting all the goodies such as ignition, coil, 240sx tb, hi-pro 8mm wires, and all that goodies.. I was wondering and never could find out what injectors to use on an engine like this and also how much HP / Torque to expect once I am done? Will I need to use an aftermarket EFI and what are advantages and costs to that or do I just need larger injectors or both? Pls let me know so I can plan The car is an '83 280zx N/A btw. I will be using F54 block and N47 head I believe unless you guys have any better opinions on the combination. Right now I have a P90 head and F54 block on my car but will be getting all the parts soon. Thanks for your help! Quote Link to comment Share on other sites More sharing options...
pallnet Posted March 4, 2003 Share Posted March 4, 2003 there is a guy in texas that's running this setup with a N42 head. he said that his compression is somehwere around 13 to 1. he said he has to run raceing fuel all the time. the car will not run off of pump gas. the name he goes under on Zcar.com is slingshot. sorry, i don't have a link to his site. i lost it with my other comp going south. personaly, i would think about the P90 and maybe shane it a little. good luck.. pallnet Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 4, 2003 Share Posted March 4, 2003 Look at your HP goals, and your expected fuel pressure to get a better guess on fuel needs. Are you looking for 250 HP or 275 or? Quote Link to comment Share on other sites More sharing options...
PhaTTy Posted March 4, 2003 Author Share Posted March 4, 2003 Hoping to get 280hp out of it.. N/A of course for now.. I want take off power.. not really high high speed.. Just wanna burn em off the line.. I am talking with someone about a nice custom intake setup with programmable EFI and such (4) 42lb O-ring injectors , Bosch regulator, Quad T-body with fuel rails, Clifford 6=8 intake, Microtech MTX-8 w/ programmer and sensors. This will be put onto a 3.1L buildup engine with F54 block and N47 (or N42 which is better) head. Any ideas or suggestions so far? Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 4, 2003 Share Posted March 4, 2003 42# will definately get the job done. As for N42 vs N47, the N47 has round ports right? Supposedly the rumor that they flow poorly is not true, however since more headers are available in rectangle port you may want to consider the N42, and they seem plentiful. I have 2 myself not counting the one already on the 240Z. I have a ported one on eBay I'm getting rid of because I'm going turbo. However if you wanted to fab up your own headers, I'd probably go round port, because that would be easier to get tubing for, to bend, and yada yada. Quote Link to comment Share on other sites More sharing options...
Guest DaneL24 Posted March 14, 2003 Share Posted March 14, 2003 I do have a few ideas for the EFI, but I would like to mention a few other things first. You've probably already done quite a bit of research on the 3.1, but I'll give you my opinion anyways. If I were you, I would stick with a P79 or P90 head. You don't need to worry about the combustion chamber size of the N/42N47 vs P79/P90 because increasing your displacement automatically increase the compression, assuming the deck height (distance from top of piston to top of block) doesn't change too much and you use flat-top pistons. This is because you are compressing a greater amount of air and fuel into the same sized combustion chamber. Just putting a P79/P90 on top of that 3.1 low end should jump your CR from 8.8:1 to at least 9.4:1, again, depending on deck height and piston type. You can always shave the head for more compression. You're using 240SX pistons and L24 rods right? If that the case, I think your deck height will be negative and you can even shave a little off the top of the block. Make sure to shim the cam towers and get thicker lashpads if you plan on doing any shaving. With a deck height of 0, compression should be between 10:1 and 10.5:1, depending on your head gasket. If you really want the N42/N47 on that 3.1, at least get a 2mm head gasket and a little bigger cam to reduce the effective CR. You might want a bigger cam anyways. Both of these heads were designed to flow 2.8 liters of air, and even then horsepower peaked a little after 5000 RPM. If you don't modify the head for better flow or get a bigger cam for your 3.1, your horsepower will probably peak between 4500 and 5000 RPM. Sure you'll kick a** off the line, but you'll have nothing on the high end. Maybe thats what your looking for, but I wouldn't recommend it. With a mild cam, like a 260 or a 260/270, you should still kick butt off the line with a high compression 3.1. If you do that, at least get a lower ratio for the rearend, like a 3.54 or 3.36 instead of a 3.9. If you put too much torque to the wheels, you'll just spin the tires. The lower ratio will help compensate for the lack of high end power too. Well thats my $.02 on motor building, now for the EFI. You can get an adjustable fuel pressure regulator and bigger injectors if you don't want to mess around with the programming. That isn't as precise though, it just kind of "tricks" the computer to injecting more gas. Kind of a trial and error process like tuning a carb too. Once again, it works, but its not as precise. If you want a programmable EFI system, look into Megasquirt. It only costs like $150 for the computer, and its fully programmable. I'm not sure about the web address, but just do a search on Megasquirt. Good luck Quote Link to comment Share on other sites More sharing options...
Guest Zcarsmakemyheadhurt Posted March 29, 2003 Share Posted March 29, 2003 Do the clifford on the MT. Quote Link to comment Share on other sites More sharing options...
PhaTTy Posted March 29, 2003 Author Share Posted March 29, 2003 MT = MicroTech? Its almost like code language lol.. what are your reasons behind this suggestion? Quote Link to comment Share on other sites More sharing options...
Guest Zcarsmakemyheadhurt Posted March 29, 2003 Share Posted March 29, 2003 Microtechs are very flexable they can learn most sensors, they are easy to tune and the features dont get out of controll. You can use conventional distributor lay our or coil packs and a optional hand programer can take datta logging to your home PC if you dont have a lap top. $1,150.00 W/O programer. Quote Link to comment Share on other sites More sharing options...
PhaTTy Posted March 29, 2003 Author Share Posted March 29, 2003 Lol Alex.. You just pop up everywhere don't you Aaron Quote Link to comment Share on other sites More sharing options...
Clifton Posted April 4, 2003 Share Posted April 4, 2003 Hoping to get 280hp out of it.. N/A of course for now.. I don't want to be the buzz kill but don't get your hopes up unless you are doing some serious head work. 140 extra hp from an extra 300cc's isn't going to happen on a stock or almost stock head. On a 6 cylinder the hp and injector cc will be about the same. 280 hp would be about 280cc per cylinder at 100% duty cycle. You could pick up some 370cc ford injectors cheap. Quote Link to comment Share on other sites More sharing options...
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