Bernardd

what happened to your timing during all of this? given it's habit of changing on you that may be the issue here. did you read datsunan's post about the loose rotor inside the distributor? do you have a spare working maf you can test? CAS? get rid of the idle control for now and adjust the throttle stop? remove all the connections under the hood (electrical) and spray them with contact cleaner. you should and probably have pressurized the intake piping to check for leaks correct?

I messed around a bit with my mbc and the turnbuckle setup I have. I set the turnbuckle to give me 20psi, then I set my mbc to give me about 17-18psi. So I get very fast spool now and a solid 20psi with no spikes. My mbc used to give me a 2-4 psi spike. I've only had it running like this for a couple of rides but it seems to work really well.

meth kit links: http://www.devilsownonline.com - best bargain out there http://www.alkycontrol.com - best support out there there's also the smc website and the snow performance kit. check out http://www.aquamist.co.uk for a forum with a lot of info on how it works, sizing nozzles, technical info, different methods of injecting (precompressor, post compressor, intake).

I had a sort of similar problem after changing out a headgasket. I went through ALL EFI connection, ecu, injectors, sensors etc... and sprayed them with contact cleaner. It's been two weeks and it's still ok. BTW that is tune was run on my car for an entire summer with no problems with either the timing or high idle. I don't use the idle control from the z31 at all. I adjust the throttle stop to the desired rpm and it's fine for me. Bernard

You MUST use methanol injection. Even with the best intercooler, there are big benefits meth. I have the specs on how to build up a jatco 4spd auto to handle 6-700hp. You'll need a manual valve body from http://www.keas.com.au to hold that kind of power. Unless you're going to use a domestic. Bernard

Take off your actuator or get another stock one from the JY. Take it to a hardware store and match up a turnbuckle with a similar size rod. Take it to a machine shop and have the loop on the end of the actuator cut off the stock rod. Cut off the loop at the end of the turnbuckle rod. Weld the actuator loop to rod you cut off of the buckle. Weld the other end of the buckle (again, cut off the loop at the end) to the stock rod. Make it the same length as the stock rod was with the buckle threaded close to all the way out. That way you can adjust from stock psi to bust a hole in the block psi. I added a spring to the gate by drilling a hole in the actuator mounting plate and placeing one end in the hole and the other thru the hole for the retainer on the wastegate swingvalve (keeps the stock rod from jumping off the rod) That's the easiest to do but you need a bunch of springs to set the boost to what you want.

Go to the hardware store and pick up a turn buckle. Have it welded onto the actuator. Turn the turnbuckle until desired boost level is reached. Or add a spring to the actuator to increase the tension (easiest). I've done both and have no boost spike. I also have a mbc like you have sitting on the bench. That way it doesn't cause any spikes. AFR's are only half (or less) the cause of knock. Timing and octane are more critical IMO. I realize you can't tune every load point, so you have to compromise at one end or the other.

FYI I have seen dyno tuned timing maps for a 3.1 turbo stroker for race gas and they set the timing to above 30deg's until well into the 20psi range. Afr's were mid to high 12's. I also have the 91 octane maps for that car's dyno session. They dropped the timing to 18deg's by 15-16psi. Bottom line is you car really crank up the timing with good octane/intercooling/tuning.

What kind of CAS does the Pathy have? I would think that the biggest problem would be fitting it to the NA distributor. You may have to pickup a turbo distributor and oil pump. Other than that it should work the same as the z31 efi setup. Does that ecu support consult? You'd have all kinds of goodies and options available for it if it does.

Fuel wise a stock nissan ecu with some tuning will do everything you need to do. You can purchase consult software that will allow realtime maptracing that would make tuning really quick and easy. Until Nistune comes out the only trace software out is the conzult program or the PLMS datascan. All other software calculates where the ecu is reading data in the maps. If you're ok with that you can download free software that will do that at http://www.zcontrol.net Check out http://www.ztechz.net to see of ecu tuning is for you or download the zemulator manual.

Read the sticky on the conversion. You have to know what you're doing before doing the conversion. Your best bet would be to convert the car to the z31 ecu first, work out any bugs, then think about upgrading. PM me if you want details on what I can do.

300hp is easy for the z31 ecu. It's maf that would be maxed out before that level. You can upgrade the maf to a z32 unit or a cobra maf to meter enough air for that level. Upgrading the maf/injectors requires reprogramming to work properly. Piggy backs don't work well with the z31 ecu, I wouldn't bother with that route.

that's for NA engines...........I wanna see turbo'd sizing......but thanks for link.

I'll send it over. Thanks.

I want to mod my water injection control board. I have the schematic and how it all works. Several of the resistors on the board control the rate of ramp up to the controller (it's a variable dc motor controller) and the turn on point. When built as per the instructions, the controller starts pwm at 2.5vdc (from the maf) with max dc achieved at 4volts. PM me if you can help. Bernard

I've forgotton to connect the hose as well, that isn't the problem. The car isn't going rich at all. It's staying around high 12's and low 13's for afr's. Gas mileage hasn't changed. It doesn't matter anymore, there's a good posibility the car will be gone soon anyway.

The car bucks like hell, and starts to knock if I don't tromp it or back off. I can certainly try loosening off the valve. Edit: I don't think loosening the valve would help in my situation. This is during accel not decel. It occurs at about 1-2 psi and above.

I've swapped my .81 housing for the .63 housing. On a part throttle acceleration around 3.5-4k I get nasty surge. When I launch car and back off a bit to control wheelspin I get the surge although not as badly as a part throttle accel. There is very little boost being built on the part throttle situation and it's making the car into a full throttle or idling ride. I had a slight problem with this with my bigger housing but only at a very specific point and never at launch. Specs: 60-1 hifi wheel .70 a/r to4b comp stage 3 .63 turbine housing older style hks bov I think I'll be putting the bigger housing back on if I can't remedy this. I should also mention that the bov could be loosened up a bit, it's held upto 28psi of pressure without leaking. Bernard

Most likely you just need to swap the chopper wheel from the z31 dizzy to the turbo L28ET. Other than the wheel difference both dizzy's have the same guts and produce the same signal depending on the wheel inside. Bernard

wow, nice afr's....who's your tuner, he really knows what he's doing....

dyno graphs are up: http://album.hybridz.org/data/2/medium/graph.JPG http://album.hybridz.org/data/2/medium/graph_2.JPG interesting note: I couldn't run the same amount of boost as what I ran on the dyno. Maf voltages went up to 4.6vdc, and I got some knock. I had to lower the boost a bit. I'm not sure how dyno's work exactly but my beside the fact that I had a great time, I don't think they load the car the same as on the street. I think I'll explore the limits of the engine setup at the track from here on. It seems like a waste when the setup on the dyno won't work the same as on the street. That's my gut feeling.

I dyno'd my car friday nite. She put down 293hp @ 6k and 268 ftlbs @ 5200. I haven't scanned the sheet yet. Mods: z31 ecu z32maf holley 255lph hi press pump 440cc injectors 2.5 to 3 in downpipe with 3in piping (pressbent after trans x member) pod air filter gn intercooler w/ 2 in piping from turbo to stock tb t04b 60-1 compressor/ .81a/r stage 3 hotside stock wg actuater with adjustable arm for boost control egt gauge. progressive alky system, with m10 and m15 nozzles spraying -40deg ww fluid (70-30 mix) rebuilt jatco 3 spd with a 2.8k stall and b&m shift kit. ngk 8-11's gapped at .035 The dyno was the mustang type. I was unable to increase the power with changing afr's and/or timing. I did gain about 30hp with increasing the boost by 2psi. Afr's were kept at12.1- 12.5 with 22deg advance at max boost. I cannot say what the actual psi was but the boost was off the 20psi of my gauge. I've tested the gauge against others and it seems to be 4psi generous at 19psi. I'm guessing it to be about 20-21psi. One thing that puzzles me is that the maf readings where lower on the dyno than on the road. The voltage dropped to 4.0vdc during the first runs on the dyno, while the same boost settings resulted in 4.2-4.4 during road testing. The 2 psi increase brought the maf readings back up. My timing chain is stretched a bit with pos 2 resulting in a deg or two of retard (power shift to higher rpm) and pos1 resulting in about 5-6deg's. I know I can improve the setup a lot with better piping but it still seems like the torque is way low. Bernard