Lockjaw

It will also go solid green when it goes into open loop, which happens at a certain RPM, and when you get on the throttle.

Maxima head, or Z head? And did you mill it? I thought the N47 had pretty large combustion chambers. Are you sure its not an N42?

I think you missed what I was saying. I asked if all V8 ones were equal length or not, and then you asked if I was talking about a V8. Get it? I was just having a little fun.

Do you have a 240Z? If so, the tach itself could be your problem. My stock tach did that when I converted to standard turbo electronics. Maybe you should try an aftermarket tach and disconnect the stock on just to see. Know anyone you can borrow one from?

I am running a Bar and Plate Spearco 221, which is a top to bottom flow with an 18x6x3.5 inch core, inlet and outlet on the same side. It is supposed to flow 1050 cfm at 1.5 psi pressure drop. Here's my personal opinion. Go with something with a low pressure drop until you get into a big turbo, ie, a 62-1 or so. The reason being the more efficient intercoolers, like crossflow models have more pressure drop, and having to make that up by increasing the boost could push a smaller turbo out of its efficiency range, and likely will. Big turbo's can handle the extra pressure and pressure drop without dropping out of their efficiecy. I fit all that into my car, so it can be done, I can send you a pic or two if you would like. You can check Road Race Engineering for some different models, I got mine from TopEnd and they matched a cheap price I found on the internet, and can hook you up with that info as well. Run 2.25 lines if you want it to be easy, 2.5 if you want to pull your hair out. HAHA

More info needed. Does it idle fine? I would start with the basics. Check your fuel pressure, float levels, and then adjust the needles per Z therapy specs. esentially turn all the way in and back out 2.5 turns, and adjust for fastest idle from there. You could also make sure you have springs and fluid in the pistons. See if you can get Norms attention too, he is likely the best source of SU info.

Aren't they sand cast? Good luck, thats all I know.

If I told you it would just piss you off. ALOT.

That pretty much sums it up. You also have a larger turbine (generally) on a hybrid then a T3, and if you read Corky's book, there is a sentence that goes something like this. Big turbines make big power. You need to choose wisely if you are not going to run more then 12 psi. To big a compressor will not run as well as a slightly smaller one.

Do you mean on a V8 car or on a Z car? I could have some fun with you, but I won't this time.

That should be a flat top engine, and it will give you some compression with an N42. Mild cam and header with exhaust, and you are good to go. Good luck.

The P79 has the same combustion chamber volume as the p90. The N42 has less chamber volume, so it will give you more compression UNMODIFIED. If you mill the head, I would use the P79 or P90, but if you do not know how to set up a head and shim the cam towers and all that mess, this is best left alone. There are several threads on this subject in the archives, and I would suggest you look them up, if the search function is working. I have a less then popular view in that I think the P series heads are the best, but don't want to get that mess stirred up again. The bottom line is the easiest way to make more power is to use the N42 and rasie your compression. Maybe mill it 15 thousandths just to true it up.

Why don't you find out what a nice street driven turbo Z runs, and then see what a V8 car runs. I would go with the turbo 6, but that is just me. I have not had anyone in my Z club with a V8 match the 1/4 mile times of my ZXT, and I am going on 5 years on the same engine. Lets see them do that and race it too. Besides it is much more fun to beat up on a v8 with a lowly 168 cubic inch L6. I would say though that an LT1 or LS1 with 6 speed would likely get better mileage then the 6. If you retained the EFI.

89 300ZX NA ecu set-up to run the 420CC injector, and the Cobra MAF. It should have the same ignition map as I had prior to having the fuel map raised from 2.5 bar to 4 bar. Clark also added a half volt step in it since the turbo is likely capable of flowing more air that the ECU can send voltage to the flow meter. You mainly have to change the way the fuel pump relay grounds, add dropping resisters to the injectors, and wire up the maf, other then that it is plug and play, and it runs pretty good. Plus it never breaks, you don't have to retune it for every little change, and it makes good power, IMO. I don't have a race gas program though.

So are all V8 manifolds equal length with regard to runners? Just thought I would throw that question out there.

That is my concern, the crank angle sensor on an 81 is on the dampner pully, on the 82 to 83 it is in the Distributor. If you have the right distributor, I don't see why you would not be set. Good luck.

After 10 months, the ZXT is finally running. I had some initial problems with the intercooler lines not wanting to stay connected at 7 psi, but I think I have a handle on that now. Also have 2.5 in lines, and spearco 221 intercooler, and had JWT upgrade the ECU to a 4 bar fuel map and a half volt step. Got the boost up to about 13 psi, and it feels pretty good so far, but I want to hook up the exhaust so I can hear the motor better, so I am leaving it alone for now. Initial compariosn to my TO4b/T3 (H trim compressor and stage 3 turbine) are that spool-up takes a little longer, perhaps 300 rpms, and I don't get as violent a hit like I did with the Stage 3. I haven't really played with it enough yet to know for certain, but I think I can get that worked out to be a little more responsive. I have a turbo XS boost controller that I am going to run to the top port on the WG, and will use my adjustable controller on the bottom port to try and manipulate it to spool faster. It feels pretty good at 13 to 14 psi, would really like to see it with 6 or so more psi and see what it does. The ECU upgrades really make a difference on cold start, I guess the boys at JWT have made some progress in that regard. Very smooth. When I get to the track I will let you know how it does. Hoping for low 12's this time at about 120mph. I guess we will see.

Oh and the old BAE manifolds they used to hang those on will warp like a banana if you don't keep the thing fueled. Don't run them lean.

I think that means you have an E compressor and turbine housing. Rayjay's are a copy of a TO4B, and are old technology. I used to have one, and the parts are worth a little money since some people still like them. A more modern turbo would perform better, but if it is in good shape, use it. I think the F housings were the largest, and I had an EF, and I liked that I could have it on or off the car in 10 minutes or less. I would try to spec the wheels and see what it has. Also if it is like mine, you need to make sure the gasket between the compressor housing and the backing plate is intact, or you will have one hell of a vaccuum leak to try and find. I had several well respected people check my car, and all could find nothing wrong with it, even after I insisted it had a vaccuum leak, and I ended up finding the problem myself. It made some hellacious boost when I fixed it. HEHE.

Triples are great and you can tune them however you and your budget desires. A simple choke swap can turn a high strung engine into a torquey one, and vice versa. They are much more versitile then the stock efi, and you can make a lot more power with them, biut they don't get the MPG an efi gets. Throttle response is better, and they sound incredible. I never had cold starting issue's with mine, and I could get you very close to spot on as far as jetting and such goes. I would like to have a set of them again, but I have moved into turbo's.

Do you have a nissan turbine housing, or do we need to try and come up with one? I am sure I can find one. That would make the swap simplier for you. Of course you have to get the swing valve deal bored out.

The turbo long block would be a better choice, but you can run the engine you have, you just have to be more careful, but since you are using an intercooler, you should be ok. You need the electronics from the turbo, the distributor drive shaft since it is different. You also have to swap out the oil pan. I like the turbo intake manifold over the NA one as well. Make sure you are running the P90 head or P79 head, any other head on top of your engine will not be a good choice. I would also swap the cam out for the turbo cam, you can run the NA cam, but I tried one and did not like it. Look for a B, J or M on the back of the cam to tell you if it is turbo or not. You thought this was going to be easy huh? Good luck.

Well he has two of them, and one is better then the other, I am not sure exactly why. If you would like, PM me and I will give you his phone number and you can call him.

Mine is 1/4 in flare, I don't know what the heck AN is and I never use a restrictor, and have not had problems either. I would find the fitting that goes into the top of the turbo first and then match up the line. Good luck with it.

I don't think you have the speed of sound to worry about there Yo. Get the one that fits the easiest. fabrication sucks. 8)