WildmaN

As it says, I need a best price on a L-28 long block, preferabley new. My dad got back to me, and said it was $2500, not counting shipping, and a core charge. It is because there is not enough demand for new engines for these. Which is a good thing mostly, because they are tough. Anyway so if all you Z folk, can look around, and keep your ears and eyes open, that would be great. Anyway you can PM me, or post here on this thread.

All aside I did a compression test on my '82, thanks to Carl. Here is the results.

#6 -150psi
#5 -140psi
#4 -170psi
#3 -100psi
#2 -150psi
#1 -150psi

Average across all 6 cylinders: 143psi pretty good all around, about a B grade, on a grading scale.

So my motor is not as bad as I thought. And I think that is why I am running rich, and can't get it leaned out anymore. Because of the low compression in #3. It gets caked with oil in a short amount of time. And the ECU dumps more fuel, to make up for the lower compression. Thus feeding all the other cylinders with more fuel, when they don't need it. But of course they are batch fired, and they are given fuel evenly. But I think I will put the 20-50 Castrol high mileage oil. It seems to slow the burning down. I will try my next oil change. Unless I get a cheaper price on a new motor for my '83. Which is where all you come in. Anyway I appreciate, any help you can give me on looking for me.

flightforlife07

flat tops or dished pistons came in the 83? I don't think there is supposed to be more than 30% difference in compression from your higest to lowest cylinder is there?

WildmaN

^^ I believe it was flat-top pistons from '81-'83, and the '79-'80 were dished. Anybody correct me if I am wrong.

SHADY280

so why dont you just put a set of rings,bearings and get the head redone for like 400 bucks and be done and have a "new" engine. good learning experience as well

lww

I second Shady's motion!

P.S. you can't really judge the quality of a motor by averaging the compression across all 6 cylinders. The most important calculation is the the greatest difference between the one with the highest compression vs. the one with the lowest compression and anything under 145psi on an NA motor is too low.

Did you do a leak down test or put a little oil in each cylinder prior to testing the compression?

Bleach

ya, that compression test is bad in my opinion.
My engine was all within 4psi of each other. 178-181 at 199,000 miles

you need a rebuild. The ECU doesn't check the O2 sensor and compensate enough for low compression. Its a really simple ECU. Not a 'learning' ECU like 90's cars.

D_Zed

Yeh great, but how high do you live (elevation wise) every 1000 ft its like 10 psi I think.

skittle

thrid shady's opinion cheaper and more benificial for it to get rebuilt.

s/cL3.0

Looks like a bad head gasket or really bad rings on #3. I think I saw a motor for sale on desertzassociation.com look around on there.

WildmaN

Okay guys, I just want to make sure you understand which motor I tested. I tested my daily driver, for the compression test. (my '82, not '83) I don't know what the compression ratio is on the '83 yet. I am really afraid to find out what it is. Anyway just wanted to make sure, you all understood which motor I was talking about. Especially when lww asked me about putting oil in the cylinders, before checking the compression. I wouldn't need to do that with an engine, I drive everyday. If it was one that was sitting for quite a while, then it makes sense. Please clear that up for me.

Now on the rebuild, I neither have the tools, space, or know how to perform that task. I know I am good at swapping motors, and that is why, I just wanted to get one rebuilt or a used one with low mileage. And drop it in, and have practically a fresh running motor.

Now I mean no offense to anybody, I just wanted to make sure we were on the right plane. And I appreciate all the comments that have been made. And keep them coming. But yes, I am looking for a motor I can put my parts onto, and drop it in. Not have to rebuild and such. Though later on, I will definately rebuild a motor, from the ground up. Because I definately want to learn how, and put another achievement under my belt.

s/cL3.0

By low milage?? 120k miles

WildmaN

Yeah I suppose you could call it low mileage, as long as the compression is still real good. Is there a reason for the certain miles you posted? Do you have a n/a motor sitting around, that runs like it should?

lww

Mileage on these motors isn't really a concern as long as they have good compression and the bearings are in good shape. Like Rod's 250k motor with awesome compression. As long as the bearings hold up, that motor is gonna outlive most of us... Unfortunately, it's all the stuff attached to the motor that go bad.

s/cL3.0

Or attached that makes the motor go bad..

SHADY280

all you need extra wildman, is the engine stand, and the allen head tool for the head studs, oh and a torque wrench, and a ring compressor. the rest is all basic tools. get the haynes out, and away you go. test the 83 motor, and see if you can drive that car in the mean time, while rebuilding that motor. besides, you would have to tear it down anyhoo, and if you screw up, your still in the same place as you started. or ship it to me, and ill do it.

skittle

I Know A Guy With An 83 Eng To Sell.

WildmaN

Okay this may be the route I go, if I don't find another motor cheaper, for my '83 280zx Here is the link.
http://www.autozone.com/servlet/UiBr...UP%7C%7EEngine

Also which motor do you think is a better choice? The 1st one or the second one?

WildmaN

How much does he want? What is the mileage on it? And it is a great strong running motor? I don't want to go through all the work for an engine, that is not solid. Let me know, and thanks for the reply.

skittle

Hey Np I'll Find Out What He Wants For It. I Know He Just Put New Pythons In It. Other Than That No Idea, He Took It Out Of His 83 For A Rebuilt One.

WildmaN

^^Pythons? Please elaborate, what are those?

skittle

Type Of Injector

RodMoyes

^^^^^^^^^ "Pythons"

RodMoyes

I just put 6 new Pythons in my Z too!!!!!!

And tomorrow I get to do it all over again to replace the defective one/ones

WildmaN

Okay gotcha man, keep me informed about the motor. And thanks again.

WildmaN

Yeah I hear you man, sucks. But you will get there, still think you should go with a aftermarket fuel rail though. I am putting my JSK on my '83, when I get a new motor for it. It will save me some headache down the road. But I did install Beck-Arnley's in my '82. Awesome injectors, without any problems at all. I have had them for a year now, or close to it.