blackbetty300zx

I just got a 88 300zx turbo 5 speed runs good besides the turbo gauge sits at - 7 and only moves up to 0 nothing in the + range. Is this normal for a stock car or is there a problem some where? The previous owner was saying something about the waste gate staying open. Any input would be great. Also what plugs and wires do you guys like to run in theses cars? I want to do a tune up. Thanks

NismoPick

Welcome to ZDriver!

That's a usual sign of a dead turbocharger, but do some checks first... Can you hear the turbo spool at all when you punch it full throttle? When driving does it pull hard above 3k rpms? Or feel sluggish? I'd start with a check over of all the intake tubing, and vacuum lines to the boost sensor and wastegate, as well as make sure the wastegate opens / closes. Also you can remove (somewhat time consuming) the turbocharger boot at the front and inspect the impeller. Should spin freely with very little play, and the blades should be straight and smooth.

As for the spark plugs: NGK.

All specs are in the FSM: XenonZ31 Reference

and also check out:

ZBUM's New Nissan Z31 300ZX Homepage

Jason's Z Site - RedZ31.Com REDZ31.NET JASONBUTTS.COM

These sites have all basic and advanced questions answered in great detail

Zuphoria

Get a cheap 40$ mechanical boost gauge and use it as a tool to determine if you do in fact not have positive boost pressure. If you dont.... like nismo said... probely need to rebuild the turbo.

rogerz

I like Magnacore wires (check their website). but Bosch or NGK work. Zuphoria is right get a real gage but $40 for one is a little high. In the real world you buy what is called a compound pressure gage. when you tag on Boost the price doubles just like something labeled Marine. here is one on Amazon

blackbetty300zx

Not what I was hoping to hear but I figured that would be the worst case ill look into it more and get a real boost gauge. Am I doing any further damage to anything by driving it with a dead turbo if that's what it is? Thanks guys

zxguy1986

No, you're just not getting the boost you expect. But first make sure the turbo isn't working. Friend of mine had his orig turbo totally rebuilt for about $300 so not a big deal. If you have to do that, good time to install a manual boost control so you can boost your torque higher than the factory-set +7 lbs to maybe +10, +11. (higher than that you will probably blow gaskets and seals.) Makes a diff you will notice - and cheap - and easy to install. You'll include a new (under-dash?) boost gauge - so that in-dash factory one won't matter much anymore. But it looks good there in the dash. Just leave it. Mother Nissan made it pretty. So leave it pretty.

Zuphoria

Why dont you post some pics? do you not know how?

blackbetty300zx

Only two pictures I have of the car right now. Have not had the time to take a look at the car much going to next weekend. Was wondering what's a good brand or model boost controller to get?

zxguy1986

I put in this boost control combined with this gauge. There are a lot of choices out there.




Just found the diags we used - if that's any help.

blackbetty300zx

Planning on going with auto meter gauges but wasn't sure about a controller. Thanks zxguy1986 for the diagrams that helps out a lot since this is my first turbo car and know just about nothing about it yet.

Zuphoria

Thats a nice looking 88T! you add her to the registry yet?
The Nissan Z and SX Registry