REDWINTERZ's N/A Rebuild Thread

[car nut]

Option 3 should involve forced induction. I'm thinking lower comp pistons, port/polish, stage 2 cams and a supercharger. Combine that with 740cc injectors and either a Walbro or TT pump and you'll have a sweet car.

[REDWINTERZ]

A supercharger would be sweet, but that's not practical on a college student budget. That would be at least twice the cost of option 2. Which is why I'm still leaning towards option 1...

[speedeast]

I'm trying to find it, but there was one I remember:

stroker kit
higher compression internals
upgraded injectors
equal length long tube headers
full dual straight exhaust
custom intake manifolds
larger throttle bodies
upgraded cams
electric fans
oil cooler w/ twin filters
accusump
some electrical changes
some timing work
professional tune
MAYBE electric water pump

wish I could find it, and 400whp is about 460bhp

[Z-owned]

I'm trying to find it, but there was one I remember:

wish I could find it, and 400whp is about 460bhp

You are probably thinking of the escort track car, one of the big things it had that you don't see on z's is itb's.

[raremotive]

A supercharger would be sweet, but that's not practical on a college student budget. That would be at least twice the cost of option 2. Which is why I'm still leaning towards option 1...

Do option one... with forged bottom end.. high compression pistons... rebuild it like stock. Don't touch the ports... unshroud the valves smoothen the pad edges. You will make fair gem of power with stock goodies.

[raremotive]

I'm trying to find it, but there was one I remember:

wish I could find it, and 400whp is about 460bhp

You are probably thinking of the escort track car, one of the big things it had that you don't see on z's is itb's.

[jedijeff123]

go with top feed injectors and screw side feed crap. it's cheaper and no more plenum pulls for injector replacement

[REDWINTERZ]

A supercharger would be sweet, but that's not practical on a college student budget. That would be at least twice the cost of option 2. Which is why I'm still leaning towards option 1...

Do option one... with forged bottom end.. high compression pistons... rebuild it like stock. Don't touch the ports... unshroud the valves smoothen the pad edges. You will make fair gem of power with stock goodies.

I'm sorry, but you're going to have to explain more in detail. Forged bottom end, as in rods and pins? And what do you mean by unshroud the valves smoothen the pad edges?

And can you run higher compression pistons on stock heads?

[es.biggs]

I wonder that as well, what is the highest safe compression on pump gas (93 over here)

Isn't it 91 in CA?

[REDWINTERZ]

Yeah 91 octane (pee water).

Would I have to run alcohol injection?

[vulcanrush]

A supercharger would be sweet, but that's not practical on a college student budget. That would be at least twice the cost of option 2. Which is why I'm still leaning towards option 1...

Do option one... with forged bottom end.. high compression pistons... rebuild it like stock. Don't touch the ports... unshroud the valves smoothen the pad edges. You will make fair gem of power with stock goodies.

once you have high-compression pistons, forged, i don't think it's stock anymore.

two, he's on a college student's budget, would be pretty tough, Rare.

[speedeast]

Alcohol or water injection could help as it cools things down. If you cool things down, then you can compromise with the lower octane. If you keep the EGR, that will help keep things a little cooler as well.

[es.biggs]

I dunno. I'd probably just rebuild with new internals and call it a day. For a college student, daily driving the car, that is what I'd do. When fit hits the shan, it can get tough if you don't have a bankrupt plan with your parents lol.

[REDWINTERZ]

That's kind of where I'm heading. It's always fun to thing about stuff like high compression, nitrous, and forced induction, but being broke in college and having one of these things come back to bite scares the $#!% out of me.

As long as the rods are ok, they don't need to be replaced do they? What about other internals?

[Z-owned]

could always use Toluene to increase the octane rating if you wanted to run the higher comp.

[speedeast]

It's really just a matter of parts that are subject to wear. Piston rings, main/connecting rod bearings, etc should be replaced. If you are concerned doing this while you're a student, don't worry about it. There will be plenty of time when you get done with college. I wanted and wanted when I was in those shoes too, and I m just now doing my project, but conditions are better than they possibly could have been if I had tried to do this a few years ago.

[speedeast]

could always use Toluene to increase the octane rating if you wanted to run the higher comp.

Your car is soooo sexy.

[es.biggs]

Concept Z Performance has main and connecting rod bearings.
http://www.conceptzperformance.com/Cart ... .188.136.5

Do you know how to check bearing clearances, and check the cylinder out of round, etc.?

[REDWINTERZ]

]
Do you know how to check bearing clearances, and check the cylinder out of round, etc.?

Not really, no. This is going to be a serious learning experience for me... Teach away, people of NICO!

[ffrpwner]

build engine single turbo run at a low psi till you get more money haha....it would be different...

here are some single turboed zs for ya

http://www.youtube.com/watch?v=y3zwQPtlTJU

http://www.youtube.com/watch?v=XyklSDFQzbs

http://www.youtube.com/watch?v=V1B6ohvoUJU

[es.biggs]

to check bearing clearances you need to get plastigage - its little pieces of plastic that you put between the bearing caps and the crank after you clean them up. You torque down the bearing caps to spec, then remove and the plastigage will be smashed down a little, causing it to flatten and get wider. The wider the plastigage the tighter/smaller the bearing clearance, which is good. The thinner the plastigage is, the larger the clearance, which is bad. You can measure the plasitgage and use the numbers you get to determine what size replacement bearings you need to get to bring everything as close to factory spec as possible.

That's just plastigage, it sounds complicated but if you do your research which I'm sure you will, then you will figure it out. Its not complicated like it sounds. The plastigage is found at autozone or other parts stores for like $5

I just found a reallly good vid about how to do it. The guy is ridiculously boring, but he does a good job of showing how to use plastigage.

http://www.youtube.com/watch?v=ulDX9Y4n0e0

[REDWINTERZ]

That's awesome!!! Thanks a ton!!

And what do you mean check the cylinders out of round? Will it matter if I bore out and do oversized pistons? Oh, which reminds me, I was talking to Aaron about ten minutes ago and I had a thought:

Will oversized pistons and the increased volume max out my injectors? I really don't want to run max duty and end up wrecking them, or running lean and detonating.

[raremotive]

to check bearing clearances you need to get plastigage - its little pieces of plastic that you put between the bearing caps and the crank after you clean them up. You torque down the bearing caps to spec, then remove and the plastigage will be smashed down a little, causing it to flatten and get wider. The wider the plastigage the tighter/smaller the bearing clearance, which is good. The thinner the plastigage is, the larger the clearance, which is bad. You can measure the plasitgage and use the numbers you get to determine what size replacement bearings you need to get to bring everything as close to factory spec as possible.

That's just plastigage, it sounds complicated but if you do your research which I'm sure you will, then you will figure it out. Its not complicated like it sounds. The plastigage is found at autozone or other parts stores for like $5

I just found a reallly good vid about how to do it. The guy is ridiculously boring, but he does a good job of showing how to use plastigage.

http://www.youtube.com/watch?v=ulDX9Y4n0e0

Just to make your life a little more s***.

Albert Einstein believed there no such thing as a perfectly straight line. He was right with the crank, all cranks have a slight bend in them. This is what you do to check the crank properly. The center bearing journal, the ideal location for a thrust bearing, is where you check. First you lay all your bearings in the block. Then you put the crank in and set up a dial indicator at the very top of the center journal bearing.. and rotate the crank... behold you are up to 0.0004 of a inch bent of a crank! (obviously each crank is bent a little differently, but i used an example number...0.001" crank is heard of and still good). What it means is 0.0004" of oil clearance is taken out of the clearance as it rotates. This value comes from measuring round out at the center of the crank, which in my example I had an round out of 0.0008"..then I half it to determine how much clearance it took out.

To properly tolerance you motor.. you need to dial in your highest point on the crank with the indicator, by rotating it in the block. And place plasti-gauge at that center point of the crank. And measure your true tolerance.

See your world of crank tolerances just got a little bent. Thanks Albert.

Also, inside your FSM states the bearing clearance. For performance you build on the looser side of things, it lets more oil through the system. And allows for the greater deflection caused by increase in power and rpm abuse. Obviously with more oil used means less oil pressure during the higher revs, but nothing a higher volume oil pump can't fix.

[es.biggs]

^^^^Great points f8 - I was expecting someone to come in and make any necessary corrections lol

I pay a grand a semester at my community college and through my first engines class I hadn't even heard any mention of that.

So, to do the plastigage the right way, you need to find where the crank is closest to the top of the center bearing cap, then make measurements at that position?

Something I can't remember - aren't all measurements supposed to be made at the same time? In other words, lay plastigage on the crank at every main bearing and torque all caps down properly, then remove the caps and read the measurements?

OR

should the dial indicator be used for every bearing, individually, so each clearance is measured when the crank is closest to the top of the journal for every measurement?

[REDWINTERZ]

This is where I stand back, and let you guys who know what you're talking about do your thing Thanks again guys!

[es.biggs]

This is where I stand back, and let you guys who know what you're talking about do your thing Thanks again guys!

By that you mean Rare_f8?

[REDWINTERZ]

By that, I mean anyone who knows more than me... So NICO

[raremotive]

So, to do the plastigage the right way, you need to find where the crank is closest to the top of the center bearing cap, then make measurements at that position?

Something I can't remember - aren't all measurements supposed to be made at the same time? In other words, lay plastigage on the crank at every main bearing and torque all caps down properly, then remove the caps and read the measurements?

Yes, you find the highest point and measure from there. The center should be checked because it's most likely where buckling occurs, most deflection. Think about a thin diameter cylinder shaft with two unbalanced flywheels on each end of it... spin the shaft and the vibrations begin. The flywheels will wobble in the axis direction, the shaft transfers that deflection, but it has mass on both sides...which resists the deflection. Finally resulting it buckling in the center to maintain it's rotational movement.

You can check all the high points of all the journals... but can you imagine unbolting and rebolting the main caps for the number of journals the engine has?! At most I would do it twice, the center and the outside edges. (maximum for VG30 with 4 mains, but it's a time consuming with a straight 6 with 7 journals..)

Your measurements are not going to be the same.. that's why there is a tolerance. The most accurate method is to use a bore gauge, then use the plastigauge to true clearance... using it at 3 points.. the ends of the crank and the center.

Not much you can do to change your clearance. Most just buy ACL and drop them in check see if you are in tolerance. Nissan already gave you specs for your engine... it's those numbers on the crank.. and bottom face of the block. Those are numbers to determine grades of bearings, different thicknesses. For instance you take the first number off the crank.. 1.. and then the block...0. Add them up 1+0 = 1... which means it uses a grade 1 bearing. (it's in the FSM....) You can take it further and order the bearing to you want in tolerance from your initial measurement from the bore gauge.

You can get away with buying ACL bearings. I just like to put a little more effort in mine.

Red... best place to start.. is buy a paper copy of the FSM and read it.

[Ace2cool]

Haha, I love this kinda stuff, when people are ready and willing to help out.

I know how to use plastigauge, helping a guy at the auto hobby shop rebuild his oldsmobile engine. We've got precise measurement tools if we need them, so no worries there.

[REDWINTERZ]

Well, last night I started the tear-down.

Got the IACV off


Way too much loctite - man that was a pain

Pulling the upper intake manifold

Lower intake manifold, with enough liquid gasket for all of our cars. And then some.


The aftermath, for today


Plan for now is to clean and box up the upper intake manifold, and then hopefully get the timing belt and heads off before the end of next week. School is getting closer