1985 z31 advice

Whats up! I'm a newbie (as you guys would call me). I'm full of questions concerning the Z31 and any help will be greatly appreciated.

I got the car from my wives grandfather for $150.00 and all it needed was a new timing belt. About 2 years ago, someone began to replace it but never finished. They had it all torn down but except the timing belt cover and harmonic balancer then left it that way. After towing the car 200 miles back to my house I began to repair it. In about 2 days I had it running, the plugs were bad the ignition was out of time and the plug wires were bad. (I also changed the oil). I've got it all fixed but its burning a little oil and never did it before it sat up that long, it does it less and less ever time i let it run, Any ideas on what it might be??? Its also has a lot of condensation and steam coming out the exhaust. I don't think its coming from the heads because it only happens now and then, its not constant. I'm not sure whether or not to invest a lot of money into it, so any advice could help. thanks

The steam coming out the exhaust is going to be from the cat and from the U bends in the exhaust. When you burn petrol (gas for you americans), the byproducts are water and carbon dioxide (and a whole bunch of other shit due to incomplete burning, secondary reactions involving the nitrogen in the air etc.)
This water generally condenses back into liquid in the cat and the u bends, given enough time. Don't worry about that aspect.

As for the burning oil, as you said its doing it less and less each time, so I probably wouldn't worry about it.

-Mike

yeah probably burning oil, due to it sitting for so long...the seals probably dried up pretty good causing them not to seal as tight as they are supposed to. as they get mroe lubricated and used they will expand almost back to normal. good luck...is it a turbo or n/a??? treat her good and she will treat you even better.

That eases a lot of worries. thanks. It is a turbo. I would like to start looking at performance accessorys such as an innercooler, p+p heads, cams, catback exhaust, MSD ignition, boost controler, ect. I've dreamed of owning one of these cars since I first got my drivers license. now I do but scared of the motor, its got a lot of miles but I'm not sure if its original, it doesn't knock or tap, and seems to run real good. I also don't want to spent a lot of time and $ only for it to blow up in my face later. ya know?

Have you changed the timing belt? If you haven't, do it NOW before you run the engine any further.

EDIT: Nevermind, i just re-read your first post. Looks like I need another coffee. :/

-Mike

Alot of time when a car set for along time the rings kinda get gummed up and cause oil burning, but with running the gum breaks down and everything is OK.

you should run her for another week or so, just to get everything working in tip top condition then run some of that seafoam stuff through her to clean out all the carbon deposits in it.. probably put a bit of injector cleaner in with your next tank as well... just basically get everything replaced and working tip top... maybe replace the fuel filter too... and the vacuum lines too.. hell, replace anything rubber in there


well maybe not... i'm just crazy

I'll see how it goes and let you guys know. I plan on putting an electric fan in place of the mechanical one to free up some HP. What size should I get? I don't want it to overheat with too small of a fan, because of the turbo. Also do you guys know what makes the Z32 N/A 3.0 (200hp+?) so much more powerful than the Z31 3.0 N/A? (160hp)

I'll see how it goes and let you guys know. I plan on putting an electric fan in place of the mechanical one to free up some HP. What size should I get? I don't want it to overheat with too small of a fan, because of the turbo. Also do you guys know what makes the Z32 N/A 3.0 (200hp+?) so much more powerful than the Z31 3.0 N/A? (160hp)

DOHC (Dual Over Head Cam) and Variable Valve Timing are the biggies...plus nissan probably just re-did the engine to make it a little more powerful to keep up with competition. they could have made the VG30E in the Z31 push more HP but it wasnt needed in 1984...you know what i mean??? your Z31 turbo should be able to take out a Z32 N/A if your Z31 was running well...

I'll see what I can do with a little P+P and tuning. Did the Z31's have positive traction? How bout the Z32's, did they?

I'll see what I can do with a little P+P and tuning. Did the Z31's have positive traction? How bout the Z32's, did they?

some Z31's have LSD but not all...im sure yours does since its a turbo. there is some discrepency on the 86's...some people say that even the N/A's had LSD but some people say the opposite...

and Z32's all have a VLSD, N/A's are a different gearing...thats the only difference.

since you have a turbo model... im sure a cone filter, full exhaust (turbo back), and boost controller would put a nice hop in its step. im not too sure about modding Z31's but im sure it is identical to Z32's....ECU, exhaust, and intake should be your first performance mods.

Any suggestions on brand's? I know their not all the same.

Any suggestions on brand's? I know their not all the same.

i would get a K&N cone air filter, custom mandrel bent exhaust with a high flow cat or no cat at all (depends on where you live and if you can tollerate a crazy loud car), and a Jim Wolf Technology ECU upgrade....

also, the greddy profec-b is the probably the most popular choice by tuners, for boost controller...you will have to search for the maximum boost the VG30ET can handle on stock internals and fuel injectors...

that should be a good start... http://www.jimwolftechnology.com is probably your best bet for parts, they know their stuff. its hard tof ind parts for the Z31 but they carry alot of parts that are needed to make one hell of a Z31...

after that, look to start spending some serious cash...clutch might start slipping due to the extra power, fuel injectors will probably be close to maxed out, intercooler kit may be in need, MAF upgrade is gonna be needed to able the engine to suck up enough air (i think a cobra mustang MAF is the upgrade for the Z31, but im not sure)...like i said though, im not sure on how to go about modding Z31's to serious numbers and what is needed when...

Where I live emisions aren't checked and your car has to be extremely loud for the cops to screw with you. I'll check into that site and appreciate your info. thanks

usually 10-12 psi is recommended on stock stuff, up to 15 psi with an intercooler, but after that you'll start breaking things without the proper upgrades

After seeing some of the prices I'll start with the filter and exhaust (I know a guy who will do the exhaust for cheap no cat either) the rest will have to wait for me to save some $$$. Those upgrades to the induction and exhaust will help the turbo push more PSI, right?

After seeing some of the prices I'll start with the filter and exhaust (I know a guy who will do the exhaust for cheap no cat either) the rest will have to wait for me to save some $$$. Those upgrades to the induction and exhaust will help the turbo push more PSI, right?

yeah, it will up PSI a little...

well it's pretty hard not to increase the boost from the stock 4-5 psi... but i'd get a boost controller for the hell of it, bump it up to 8 and you'll be golden with 93 octane..

this is probably the perfect filter you're looking for.. i ordered mine a few days ago but it hasn't come in yet..

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7958230197&category=33659

Damn, I thought they had more PSI than that. I think I need to get a little more educated about this car. I'll start looking into that greddy boost controller, and that filter. thanks.

hey projectz31 post some pics of the ride ide like to see what kind of condition it looks like ... i bought mine for $150 too but sadly i need some work done to it and read all u can bout the z31 because theres alotta common problems...

hey projectz31 post some pics of the ride ide like to see what kind of condition it looks like ... i bought mine for $150 too but sadly i need some work done to it and read all u can bout the z31 because theres alotta common problems...

You need to start working on that weight problem.....

lol yah when i start my journey ill be postin pica

don't everthink about running a z31 w/o intercoller over 10psi, I have a z31 turbo boost controler + blewofvalve, K&N filter, HKS exhaust system. i was running it 8psi w/ no problems, then i believed somepeople and starting running it 12 psi. i have had alot of problems since that, but fun to drive. faster than mustang cobra 1995.

don't everthink about running a z31 w/o intercoller over 10psi, I have a z31 turbo boost controler + blewofvalve, K&N filter, HKS exhaust system. i was running it 8psi w/ no problems, then i believed somepeople and starting running it 12 psi. i have had alot of problems since that, but fun to drive. faster than mustang cobra 1995.

You should look into water/alky injection. I'd bet you'll end all your problems if you do. I'll also bet you'll be able to go above 15#.

some Z31's have LSD but not all...im sure yours does since its a turbo.

The Z31 turbo did not have a LSD until 87. You can find a clutch LSD out of a 87-89 turbo for ~$200 very easily that will swap right in or you can buy a new R200 clutch LSD from the factory for...like...$700 or something.

If you have ANY questions about the Z31T or need any parts or anything, PLEASE PM me. I can find you just about anything you want info or part wise.

For an e-fan, get yourself a Jeg's catalog and order yourself the 16" Perma-Cool fan...that pulls more than enough air for the Z31 (2800CFM, I believe)...and while your in there, order yourself a "universal" K&N Cone filter...I can get the part number for you if you need it and I can tell you how to install if you need me to. It takes about 3 minutes and the only tool needed is a screw driver. It's the ~6" one...should cost $40-$50...it'll flow more than enough air for our little 3.0L engines. After that, find yourself someone that'll make you a custom MANDREL BENT exhaust system and you'll be ready for a boost controller. Sounds like you got a pretty good deal, man. Don't be too wary of it...they're GREAT cars. I'm on my 3rd one. I love them. I'd give it a little while to get back in the swing of things, then I wouldn't worry about it any more...it just has to wake up. HAVE FUN!

Dammit...just found this second page...

You should look into water/alky injection. I'd bet you'll end all your problems if you do. I'll also bet you'll be able to go above 15#.

Not a good idea...above 15 psi, the turbo loses efficiency [sp.] and creates more heat than anything else above there. You should be able to run 12 psi without an I/C and not have any problems.

There was a GLORIOUS Turbo FAQ on Z31.com where the guy talks about the mods he has on his 86T...intake, exhaust, boost controller...he runs 12psi usually and has been for a couple years with no problems...he runs 15psi only for short times when it's cool out and has had no problems...all with no I/C. At 15psi with some half slicks, he runs ~5.4 to 60 on a cool day. All this info is gone since Z31.com CHANGED THE FAQ...I'm so pissed...

Moral of the story: Intake, exhaust, boost controller = approx Z33 performance for the cost of the car ($150 in this case) and about $700 in mods (according to the old FAQ)...God, I love Z31s...:biggrin: Just do not ever take the stock turbo over 15psi.

i too have recently aquired 2 z31 quite a steal on one of them being a 50th annevesery (not a replica or clone )although i already toasted the na the 50th is getting rebuilt as we speak just a little spicing 3" exhaust (straight ) no muffler or cat, 3' stainless steel air filter, removed ac pwr steering mechanicle fan, ignition tune up (ie high performance plugs wires cap rotor and coil), lots of exhaust wrap, oil cooler before turbo, and an externaly mounted spring to raise boost to roughly 12 psi,and some weight reduction (race seats no carpet the lttle things that arent there that counts the only thighs going to it now are head gaskets (all metal) the exhaust wrap and oil cooler all ealse was there in the last tune up

As you can see in my sig, I have my VG30ET out of my 86T (hit a curb...pulled the engine...oops...)...what to do, what to do...I'm thinking I'm gunna pull the heads for a port polish, replace all the seals and gaskets, bigger turbo, bigger throttle body, increase the fuel capacity, get new pistons and rods, balance the crank...so on and so forth...I plan on taking the whole thing apart...I think that's the only way to truely rebuild an engine...after that...I'm just gunna need a body to put it in...

Dammit...just found this second page...



Not a good idea...above 15 psi, the turbo loses efficiency [sp.] and creates more heat than anything else above there. You should be able to run 12 psi without an I/C and not have any problems.

There was a GLORIOUS Turbo FAQ on Z31.com where the guy talks about the mods he has on his 86T...intake, exhaust, boost controller...he runs 12psi usually and has been for a couple years with no problems...he runs 15psi only for short times when it's cool out and has had no problems...all with no I/C. At 15psi with some half slicks, he runs ~5.4 to 60 on a cool day. All this info is gone since Z31.com CHANGED THE FAQ...I'm so pissed...

Moral of the story: Intake, exhaust, boost controller = approx Z33 performance for the cost of the car ($150 in this case) and about $700 in mods (according to the old FAQ)...God, I love Z31s...:biggrin: Just do not ever take the stock turbo over 15psi.

Your absalutely right about boosting above 15# with stock turbo. Your at the edge of the envelop for stock turbo, I was just saying you can go higher if you chose to. I guess I better be more clear in the future, and more detailed.

Got ya...it's all good. Running at >15 psi, with or without an I/C, for any length of time would be a VERY not good idea...

well im gonna be rebuilding my z31 within the next month or 2 ......also gonna convert it to manual..yah ive heard that same thing about people runnin fine on boost below 10psi but anything after that requires a intercooler.......

are you going to rebuild and convert it to turbocharged?


lol... you mean very bad llz?:p

Yea...very not good = very bad.

Anyway...<10 psi...you can run this regularly and have no problem...10-12 psi...I'd use this as a "high boost setting" from time to time...12-15 psi...I'd use this as an "overtake boost" setting...no way I'd go over that.

I was going to get a Greddy Profec B Spec-II and it has 3 settings: "low boost", "high boost" and "overtake boost"...overtake boost is triggered by a button or remote control and will run a preset boost for a set time...10 seconds...30 seconds...whatever. I was going to set mine for 10 psi on the low setting, 12-13 on high and 15 for 15 seconds for overtake...that's the longest I'd run 15 psi without an intercooler.