z-ya

Since you are using closed loop mode, what is your target AFR table set to? All the PWM does is insure that the injector get the right amount of current required to open it. And then enough current to hold it open for the largest opening time in your map. If you are using resistors, just shut the PWM off and forget about it. Just so you know, injectors do not flow linear with respect to opening time. In fact two injectors with the same 80% duty cycle flow rate (made by two different manufacturers) can have different flow curves. So you really need to tune the base map, set the AFR target map, and then turn O2 correction (closed loop) on.

This may be a stupid question, but why not just get an RB20 MAF?

I Painted mine TCP Global california Orange. In the sunlight it is blinding. In the dark it's a kind of creamy orange.

No 280Z came with flat top pistons. Having an MSD in there is not going to magically fix your detonation problems. And the 280Z pistons will break even faster than the F54 ones. So you need to get to the bottom of what is causing the detonation or plan on picking up some extra short blocks. If you can give us more information about your setup we can probably help you out.

You have to have a custom driveshaft made. Make sure it is dynamically balanced or else you will have vibration problems. I just went through this with my RB25 swap.

Nope, driveshaft. Mine is pretty much a straight shot. I brought the driveshaft back to the place that made it and had them check the balance again. It was off, but not much according to the guy that does the balancing. So they both static and dynamically (spin) balanced it. No more vibration! So even though I couldn't feel it in the shifter, it was the driveshaft. Joe, dizzle, you might want to get your driveshaft balance checked again. Thanks for all the suggestions! Pete

Shoot! Is yours a 71? Mine is a 25k VIN. The vibration is not horrible, but annoying... I've got a line on a place that can balance the wheels on the car. I figure this might help me pinpoint the problem. Woldson, I did rotate the tires from front to back with no change. There is no vibration through the steering wheel, so it's not coming from up front. The rear toe is close to zero. I am getting the alignment done next week. It has bad inner tie rods. I'll keep everyone informed. Pete

Thanks Jon. I didn't check the drive shaft angle, but it looks to all line up pretty straight. There is little to no bend at the U-joints. I installed the RT mount the same way I installed 2 previously. Didn't have any issues with them. The other thing I checked is the transmission output bearing end play. It is tight. Little to no play. I would think that any issue with the driveshaft would cause vibration to come up through the shifter. At least this is what Gilbert's Driveline said. Unfortunately they didn't have the right couplings to balance the half shafts or I would have had them balance the halfshafts as well.

You can try Skip at Durabild in Nashua NH. He knows a lot about the old Nissan comp transmissions as he was part of a Datsun race team in the early 70s. He probably doesn't have what you need, but he might be able to find it. Pete

I been trying to figure out a drivetrain vibration for a few weeks now, and I'm running out of ideas. Here are the details: - 1971 240Z - RB25DE and 5-speed - New balanced driveshaft - Poly diff mounts - Stock rubber tranny and engine mounts - Stock halfshafts - R200 mounted in stock location with 280Z Moustache bar and RT mount Behavior: - From about 45-65MPH you feel a vibration through the chassis - Seems like it is coming from the diff or halfshafts - No vibration in shifter - When engine is idling in neutral, vibration is still present (at speed) - Stock rubber control arm bushings - Eibach progressive springs What I have swapped (without any change in behavior): - Differential - Half shafts - Tires (front to back) - Brake drums What I have checked: - Rear wheels bearing (tight, no play) - Eyeballed stub axles to see if one might be bent. Seem to run true - Rear suspension (tight no play when wiggling wheel) - Rear toe is around zero (using my crude measuring method) - All half shafts U-joints tight. At this point I am leaning towards the poly diff mounts. I will try and swap the the stock front mount first. Is there a rubber version of the Chevy mount used with the RT mount? The car handles well and nothing feels loose back there, so I don't think it is suspension. Comments, suggestions, welcome. Pete

You need an EFI head. Go with an N42 as it has square exhaust ports and approximately the same chamber size at the E88 the L26 came with (the P79 will lower the CR too much). You will need to tune the stock EFI. You may not be able to get it running 100% correct. - Get an adjustable fuel pressure regulator. See if by lowering the fuel pressure you can get it to idle smooth.I wouldn't lower the pressure more than 5psi less than stock. - You can also insert a variable resistor inline with the coolant sensor to lean it out if needed. - Lastly I would screw with the AFM Pete

What about the left inner tie rod end? Is the thread rotation different where it connects to the rack or the outer tie rod. If the threads on the rack are the same LH and RH then what about using a RH outer tie rod on the left with a RH outer tie rod? Thanks, Pete

82-83 280ZX NA with 5-speed have 3.9:1 gears BTW.

Can't you just tell the dynojet what your rear end gears are and use 4th gear (1:1) for your pulls? It's a simple calculation that the dynojet "should" be able to do. I know Dynpac and Mustang dynos can. Those are dam good numbers for 7psi. Pete

Are you sure it isn't leaning out? Do you have a wideband O2? Just because you have 3psi at idle, doesn't mean you have the same at full load. Temporarily run the pressure gauge so you can see it through the gap in the hood when it's popped. See what the pressure does under load. Pete

Pop the rubber plug from the drum so that you can adjust them with a screw driver without removing the drum (you'd be surprised how many people don't do it this way). Depending on your wheels, you may be able to adjust them without removing the wheels. The R4S is a good balance between track and street. I have them on my street Z, and they are quiet, but heat up quick. On my track car I use R4 compound front and rear. Not all that much noisier than the R4S, but can handle a lot more heat, and last many track days.

I have one now that I will be testing. I will update the spreadsheet when I have the data. I measured the DC resistance and it is about 3 Ohms.

It's just a coil, right? Meaning it doesn't have the amplifier built in, correct? If that is the case, then you need a coil driver/transistor to drive it. If it only have two terminals, the it doesn't have an amplifier built in.

I ordered the rubber window Squeegees from them. They delivered them quickly and in good condition. That is the good part of the story. They cost me over $60 for the pair including clips to attach it to the trim. They were supposed to be aftermarket direct OEM replacement original squeegees. They look like they came from JC Whitney. There is no way to attach them properly to the metal trim without cutting the vertical part down. Since they have a metal center, I had to cut them with my wiz wheel length wise. So for $60, I'm not happy considering that I had to cut the "aftermarket direct OEM replacement" to get them to fit properly. http://www.datsunrestore.com/catalog.html

Very nice work. I like the way you simplified the linkage. A lot more sexy than mine as I used the stock fuel rail. I like the idea of a steel fuel rail that wraps around the head on a race car. Looks weren't a priority. Here is a fairly recent photo: Stock EFI manifold vs dual throttle body.

Witch Hunter Performance has done a great job for me cleaning and flow testing injectors: http://www.witchhunter.com/ Probably your best bet. If one or more are bad, he can probably find you a used replacement or a cross reference to another vehicle.

No stock L28 pan has any baffles. Just a windage tray, that's it.

I Think the seat of the pants feel has more to do with power:weight ratio than anything else. My Silverado pulls pretty good for a 5000lb vehicle, but my NA track car (180WHP) weighing 2100lbs feels a lot better. But lets face it, any reference to "feel" in power estimation is pointless IMO (unless you somehow had your butt calibrated for horsepower measurement ). Vehicles with different power:weight ratios are going to feel much different regardless of of how much absolute power is produced. Compare a 100HP sport bike to a 400HP truck, the sport bike will pull much harder making 1/4 the power. I suggest you get it on a dyno and MEASURE it before and after the stroker! Pete

The removed 240Z rear section you show above is mine. I swapped that onto my 240Z. Believe me, it is a lot of work. I drilled at least 50 spot welds on both the car and the replacement panel. Then I had to mig weld each spot weld. Then all the associated body work. I probably have 50 hours into the job to do everything.

+7psi=150kPa. 27 deg is probably safe with 93 octane. Yes, you can change the scale to get more VE and timing bins in the engines operating range. You need to know what you plan on running for max boost and set the VE and timing table scales accordingly.