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Discussion Starter #1
I rescued an early 74 260Z from a farmyard about a month ago. After a little work I now have it running - but not yet tuned. The motor sounds healthy enough.

I want to do a nice job of the restoration with a nicely detailed original motor - with any work done to it really just to make it run smoother perhaps with a little more power than stock (162HP on the inside fender tag).

So:

I don't want to change the motor from the L26 to anything else.

I don't want fuel injection (despite knowing it will make the motor run smoother).

My carbs are HJG46W round-tops. I like them - they look easy enough to set up and I have already started to polish them.

Stock air cleaner/filter. Doesn't look like a full complement of emmission control stuff. I live in Alberta so I don't have to worry about passing smog tests - thank goodness.

I am thinking of putting in an electronic ignition system ie MSD - what is the best for the car? Will it improve HP or just help the car run smoother at higher RPM's?

Can I get rid of the balancer assembly? I notice early 240's didn't have it - some of the tubes in my car have been disconnected from it anyway (EGR). Or will my car be the better for connecting it properly?

Don't know anything about the cam yet. I don't think I was a highlift/duration cam anyway - I want the car to purr along nicely for low speed cruising more than I want all out mid/high rpm horsepower.

Will I see much benefit from crank balancing? Any other machine work: Boring out, rehoning, deck equalising, porting the heads? I am using standard Niehoff 8mm wires, Bosch platinum spark plugs. New mech fuel pump/fileter. Plastic rad fan. Exhaust needs replaced anyway.

Any suggestions are welcomed. I don't want to go crazy - I just want a real nice looking, smooth engine with a little bit of go to it.

Thanks in advance...

Steve
 

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Discussion Starter #2
> I rescued an early 74 260Z from a farmyard
> about a month ago. After a little work I now
> have it running - but not yet tuned. The
> motor sounds healthy enough.

> I want to do a nice job of the restoration
> with a nicely detailed original motor - with
> any work done to it really just to make it
> run smoother perhaps with a little more
> power than stock (162HP on the inside fender
> tag).

> So:

> I don't want to change the motor from the
> L26 to anything else.

> I don't want fuel injection (despite knowing
> it will make the motor run smoother).

> My carbs are HJG46W round-tops. I like them
> - they look easy enough to set up and I have
> already started to polish them.

> Stock air cleaner/filter. Doesn't look like
> a full complement of emmission control
> stuff. I live in Alberta so I don't have to
> worry about passing smog tests - thank
> goodness.

> I am thinking of putting in an electronic
> ignition system ie MSD - what is the best
> for the car? Will it improve HP or just help
> the car run smoother at higher RPM's?

> Can I get rid of the balancer assembly? I
> notice early 240's didn't have it - some of
> the tubes in my car have been disconnected
> from it anyway (EGR). Or will my car be the
> better for connecting it properly?

> Don't know anything about the cam yet. I
> don't think I was a highlift/duration cam
> anyway - I want the car to purr along nicely
> for low speed cruising more than I want all
> out mid/high rpm horsepower.

> Will I see much benefit from crank
> balancing? Any other machine work: Boring
> out, rehoning, deck equalising, porting the
> heads? I am using standard Niehoff 8mm
> wires, Bosch platinum spark plugs. New mech
> fuel pump/fileter. Plastic rad fan. Exhaust
> needs replaced anyway.

> Any suggestions are welcomed. I don't want
> to go crazy - I just want a real nice
> looking, smooth engine with a little bit of
> go to it.

> Thanks in advance...

> Steve

The MSD will give better performance, a very little HP increase but better fuel burn. Do you want the motor stock for some reason? Those models don't have a very good resale so I'd skip boring it and just get a L28, save the orig. motor if you want for any resale you might get later. A 260/270 duration .460 lift cam is perfect for street driving, adds a lot of low-mid range power and gives better gas mileage. If you like the stock carbs great but I'd go with dual weber DGV's over the stocks (more personal preferance but I like them for smoother running and good gasmileage plus performance).
A 5speed trans is a great add-on also. Headers are ok but I'm real picky about what model to use, hate Motorsport's 6-2 header, it's about equal for perormance as the stock manifold and will only use Nissan Motorsports headers, very tuned and well built for the Z's. They did research when they designed these which I can't say about Motorsports brands.
The copper spark plugs are better for performance, plat. doesn't conduct well at all and is just for longer life use. There are better ones made out of silver but more expensive and real expensive plugs by torque master work very good but very very expensive.
The Z's really need a front air dam, they don't like high speeds to much stock so I'd consider one. Better performance and gas mileage and engine cooling is worth it.
There is ton's of things you can add to the Z's, too bad aftermarket heads isn't one of them. Don't have the head ported or you'll lose the low end torque what little there is. Chances are it will end up running worse anyway and it costs a ton. It's hard to find a place that is good enough at porting and if you don't kiss the head goodbye. If you want, match the intake manifold to the ports and smooth any rough edges you find and leave it at that. The only work I'd have done is to unshroud the intake valves to help them flow better.
You might put some high quality gas struts in it, it is worth it but I'd keep the same springs or the euro springs but don't lower it. It may look better but the overall handling of the car suffers on rural streets, it's better for racing really and not a good improvment for a street car unless you go through all the trouble to get the alignment back to stock. The car handles good anyway and adding good tires and struts will give it all it needs though you might add some better sway bars, the stock ones don't really cut it. Hope you have a lot of money hehehe..... good luck
 

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Discussion Starter #3
Sounds like no-one has any real preference with respect to the manufacturer of the aftermarket ignition system - fair enough.

I just like the idea of using the original motor with the car. I am by no means a purist when it comes to restoration - I plan to put on a nice set of chrome Enkei rims + customise the interior. I will also do some nice things with the paint.

Thanks for the info about the cam - Crane cams seem to be very well though of - I will have to assess what is in the car first.

I'll think about those Webers.

I'll see how I like to 4-speed on the highway before springing for a 5 speed. I drive 100km/day total round trip to work. Almost all highway.

Good info about spark plugs. NKG seem very popular with these cars - I will see if they offer a copper variety. I am a bit wary of silver - silver oxidizes doesn't it? Surely the performance of silver plated plugs would deteriorate quickly?

I have a front air dam. I must say - I prefer to plainer look of Z's without it but I have some ideas about how I can incorporate it into my paint design. Also a friend of mine had a 240 and said it became quite scary driving at high speed without a dam. Typically I don't exceed 180Km/h 120 Mph.

Thanks for info on machine work - I won't rush into anything.

As for lowering - the car currently has 196/60/14 rubber (14 rims obviously). This lowers the car somewhat and I like that slightly lowered look. I had considered looking into lowering the car ever so slightly and running taller rubber than what is on it. Reason is that I am not as happy with how well the rubber on it fills the wheel wells. I have to do some thinking about it before I step into a major purchase decision with the Enkei's.

I love high speed cornering (I used to live in N. Ireland so I am a big fan of driving insanely fast around hilly tight corners - there just isn't enough up here in Alberta... sigh). I have heard it is a good idea to upgrade all the bushings. How reliable is the steering? I definitely want something I can trust when cornering.

Also - the car will only be run in summer - +30 Celsius - is there cooling system upgrades I should consider? I am already going to upgrade to a three core radiator assuming there is sufficient fan clearance.

Many thanks for your comments...

> The MSD will give better performance, a very
> little HP increase but better fuel burn. Do
> you want the motor stock for some reason?
> Those models don't have a very good resale
> so I'd skip boring it and just get a L28,
> save the orig. motor if you want for any
> resale you might get later. A 260/270
> duration .460 lift cam is perfect for street
> driving, adds a lot of low-mid range power
> and gives better gas mileage. If you like
> the stock carbs great but I'd go with dual
> weber DGV's over the stocks (more personal
> preferance but I like them for smoother
> running and good gasmileage plus
> performance).
> A 5speed trans is a great add-on also.
> Headers are ok but I'm real picky about what
> model to use, hate Motorsport's 6-2 header,
> it's about equal for perormance as the stock
> manifold and will only use Nissan
> Motorsports headers, very tuned and well
> built for the Z's. They did research when
> they designed these which I can't say about
> Motorsports brands.
> The copper spark plugs are better for
> performance, plat. doesn't conduct well at
> all and is just for longer life use. There
> are better ones made out of silver but more
> expensive and real expensive plugs by torque
> master work very good but very very
> expensive.
> The Z's really need a front air dam, they
> don't like high speeds to much stock so I'd
> consider one. Better performance and gas
> mileage and engine cooling is worth it.
> There is ton's of things you can add to the
> Z's, too bad aftermarket heads isn't one of
> them. Don't have the head ported or you'll
> lose the low end torque what little there
> is. Chances are it will end up running worse
> anyway and it costs a ton. It's hard to find
> a place that is good enough at porting and
> if you don't kiss the head goodbye. If you
> want, match the intake manifold to the ports
> and smooth any rough edges you find and
> leave it at that. The only work I'd have
> done is to unshroud the intake valves to
> help them flow better.
> You might put some high quality gas struts
> in it, it is worth it but I'd keep the same
> springs or the euro springs but don't lower
> it. It may look better but the overall
> handling of the car suffers on rural
> streets, it's better for racing really and
> not a good improvment for a street car
> unless you go through all the trouble to get
> the alignment back to stock. The car handles
> good anyway and adding good tires and struts
> will give it all it needs though you might
> add some better sway bars, the stock ones
> don't really cut it. Hope you have a lot of
> money hehehe..... good luck
 

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> Sounds like no-one has any real preference
> with respect to the manufacturer of the
> aftermarket ignition system - fair enough.

> I just like the idea of using the original
> motor with the car. I am by no means a
> purist when it comes to restoration - I plan
> to put on a nice set of chrome Enkei rims +
> customise the interior. I will also do some
> nice things with the paint.
1) As time goes on and the engine tires out you will want to consider the L28. It has more HP and torque than the L26. There are many reasons the L26 was made for only 1 year.
2) When looking at rims be very careful. The 240Z-260Z-280Z-280ZX use a very unusual '0' offset wheel which is very difficult to find today. Offset is the distance from the centerline of the wheel to the mounting surface. Backspacing is a similar term that measures from the inside edge of the wheel to the mounting surface. On a 7 wide wheel '0' offset would be 3 1/2 backspaced. If you are planning on changing wheels I wou suggest you go to a 16 x 7 with either 205/55-16 or 225/50-16 tires. That is the maximum tire/wheel width that will fit under the wheel well and be rotatable front to rear. It also looks very nice. I purchased a set of aluminum Centerline Trident II's. They come in several different looks that Centerline will build to fit your car.

> Thanks for the info about the cam - Crane
> cams seem to be very well though of - I will
> have to assess what is in the car first.

> I'll think about those Webers.

> I'll see how I like to 4-speed on the
> highway before springing for a 5 speed. I
> drive 100km/day total round trip to work.
> Almost all highway.
3) Since most of your driving is highway I strongly recommend the 5-spd. It will make a significant diffenece in engine rpm. Doesn't affect fuel economy that much but will make a significant difference in interior noise and engine longevity. The best combination is the later model 5-spd (.745:1 OD) out of the '81-83 ZX's along with a 3.90 R200 differential. Give the best highway cruising/accelleration combination.
> Good info about spark plugs. NKG seem very
> popular with these cars - I will see if they
> offer a copper variety. I am a bit wary of
> silver - silver oxidizes doesn't it? Surely
> the performance of silver plated plugs would
> deteriorate quickly?
4) I vote for the NGK plugs too. I've tried every type plug known tomankind over the last 30 years and, for the Z, nothing is clearly superior to the NGK's - just harder to get and more expensive.
> I have a front air dam. I must say - I
> prefer to plainer look of Z's without it but
> I have some ideas about how I can
> incorporate it into my paint design. Also a
> friend of mine had a 240 and said it became
> quite scary driving at high speed without a
> dam. Typically I don't exceed 180Km/h 120
> Mph.
I have the Motorsport Aero II kit on my Z. It is rock solid at 180kph. It has the side panels and rear spoiler in addition to the front air dam but it is probably the front air dam that contributes the most to the stability.

> Thanks for info on machine work - I won't
> rush into anything.

> As for lowering - the car currently has
> 196/60/14 rubber (14 rims obviously).
> This lowers the car somewhat and I like that
> slightly lowered look. I had considered
> looking into lowering the car ever so
> slightly and running taller rubber than what
> is on it. Reason is that I am not as happy
> with how well the rubber on it fills the
> wheel wells. I have to do some thinking
> about it before I step into a major purchase
> decision with the Enkei's.
5) See my comment #2 above. Be careful with the idea of lowering the car - especially if you're looking at it as a daily driver. The Z has a lot of overhang front and rear and you'll be hitting curbs a lot if you lower the car. Also, if you use shorter springs to lower the car you'll need to use different struts too. This will end up setting you back $600-800 US.
> I love high speed cornering (I used to live
> in N. Ireland so I am a big fan of driving
> insanely fast around hilly tight corners -
6) My mother was born in County Armaugh and I love to drive insanely fast around tight corners - maybe it's an ethnic thing?
> there just isn't enough up here in
> Alberta... sigh). I have heard it is a good
> idea to upgrade all the bushings. How
> reliable is the steering? I definitely want
> something I can trust when cornering.
7) Definitely upgrade all your suspension bushings and steering coupler to urethane. It will tighten up the steering and provide more feedback. The basic steering system is excellent. Remember, though, the car is 25 years old and all the rubber stuff is probably shot and your springs and struts are probably sagged and soft. NOthing inherently dangerous but the handling improvement obtained with renewing all those parts is phenomenal.

> Also - the car will only be run in summer -
> +30 Celsius - is there cooling system
> upgrades I should consider? I am already
> going to upgrade to a three core radiator
> assuming there is sufficient fan clearance.
7) Just go through the entire cooling system. Make sure it is clean, that you have the three row radiator and a good water pump, and you'll be fine. I run my car in Texas in the summer (40°C+) with the A/C o full blast with no overheating problems. I also run the 71°C thermostat to help it stay a bit cooler than the standard 82°C. It still has plenty of heat when it's -10°C outside. The heater will cook meout of the car.
> Many thanks for your comments...
You're welcome,
Phantom
 

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Discussion Starter #5
Great info - much appreciated.

> 1) As time goes on and the engine tires out
> you will want to consider the L28. It has
> more HP and torque than the L26. There are
> many reasons the L26 was made for only 1
> year.

I'll play that one by ear. I may as well get the enjoyment out of the motor that's in it but may be I will keep it stock and build up an L28 over a period of time. I'll think about it.

> 2) When looking at rims be very careful. The
> 240Z-260Z-280Z-280ZX use a very unusual '0'
> offset wheel which is very difficult to find
> today. Offset is the distance from the
> centerline of the wheel to the mounting
> surface. Backspacing is a similar term that
> measures from the inside edge of the wheel
> to the mounting surface. On a 7 wide
> wheel '0' offset would be 3 1/2
> backspaced. If you are planning on changing
> wheels I wou suggest you go to a 16 x 7 with
> either 205/55-16 or 225/50-16 tires. That is
> the maximum tire/wheel width that will fit
> under the wheel well and be rotatable front
> to rear. It also looks very nice. I
> purchased a set of aluminum Centerline
> Trident II's. They come in several different
> looks that Centerline will build to fit your
> car.
Sizes are noted. I will be careful when picking the rims that they will be OK from the point of view of offset. Often I wish some of the photos that get published on websites had additional info with respect to suspension, rims and tire sizes. What you are suggesting sounds exactly like what I am looking for.

> 3) Since most of your driving is highway I
> strongly recommend the 5-spd. It will make a
> significant diffenece in engine rpm. Doesn't
> affect fuel economy that much but will make
> a significant difference in interior noise
> and engine longevity. The best combination
> is the later model 5-spd (.745:1 OD) out of
> the '81-83 ZX's along with a 3.90 R200
> differential. Give the best highway
> cruising/accelleration combination.
I'll see how the 4-speed works out. (The roads are covered in a foot of snow so it will be sometime before the car crawls out of my garage). I have a five speed in my Pulsar and it is better for highway driving true enough. That said I like to hear the motor when I drive...

> 4) I vote for the NGK plugs too. I've tried
> every type plug known tomankind over the
> last 30 years and, for the Z, nothing is
> clearly superior to the NGK's - just harder
> to get and more expensive.
I am very likely to put in an electronic ignition system - I will look again at the plugs I have in when I redo the wires et al.

> 5) See my comment #2 above. Be careful with
> the idea of lowering the car - especially if
> you're looking at it as a daily driver. The
> Z has a lot of overhang front and rear and
> you'll be hitting curbs a lot if you lower
> the car. Also, if you use shorter springs to
> lower the car you'll need to use different
> struts too. This will end up setting you
> back $600-800 US.
I will bear that in mind - like I say it would only be lowered a small amount - but maybe the 1200 CDN would be better spent elsewhere...

> 6) My mother was born in County Armaugh and
> I love to drive insanely fast around tight
> corners - maybe it's an ethnic thing?
I would say so - every one from Ireland, North and South drives like that. It has taken me a long time to get used to the idea that pointing the steering wheel straight ahead for a quarter mile can be considered racing. I know there is driver skill invollved in the shifting but a race isn't a race without a few blind corners...

> 7) Definitely upgrade all your suspension
> bushings and steering coupler to urethane.
> It will tighten up the steering and provide
> more feedback. The basic steering system is
> excellent. Remember, though, the car is 25
> years old and all the rubber stuff is
> probably shot and your springs and struts
> are probably sagged and soft. NOthing
> inherently dangerous but the handling
> improvement obtained with renewing all those
> parts is phenomenal.
Already in the plans. I want the handling nice and tight and the steering especially so.

> 7) Just go through the entire cooling
> system. Make sure it is clean, that you have
> the three row radiator and a good water
> pump, and you'll be fine. I run my car in
> Texas in the summer (40°C+) with the A/C o
> full blast with no overheating problems. I
> also run the 71°C thermostat to help it stay
> a bit cooler than the standard 82°C. It
> still has plenty of heat when it's -10°C
> outside. The heater will cook meout of the
> car.
Good stuff. I have heard lots of stories about people turbo chrging their Z's and having to fairly drastically improve the cooling capacity. I just want to make sure that the cooling system isn't being pushed to its limits in a standard vehicle.

Good info - I am just starting out but having a blast so far. I am still getting over the fact that I was able to replace the starter without having to pull the motor or even crawl under the car...

Great motors to work on.

> You're welcome,
> Phantom
 
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