Intakes, Heads , motors

[TBK1]

Gonna be kinda long here, SORRY!

Ok! son apparently blew up/locked up/trashed his 73 240Z motor.Havent had a chance to go over and look at it, but doesnt sound good.

what I am think is this. I have a complete 77 280 motor with 5sp sitting in the garage, problem , he took it out when it was installed in mine and now smokes like a B**ch.

Thinking it is rings, since the N47 (non-oiler rail) was recently rebuilt with new seals ect.

Thinking of pulling the plugs and powering the starter and checking compression, should this tell me if it's the rings?

would do a lower end rebuild if necessary.

now he has the dual weber down draft carbs and intake, will it fit on the newer N47 head that I have on the 280 motor? I have the complete FI on the 280z motor but would take it off, due to the expense of converting everthing. guess I can sell most or all of it.

His has the E-88 head installed.

Or would there be a better combo, to interchange between the 2

dont know which blocks either motor has but assume they are the stock blocks if there is such a thing!

Thanks for reading this long sh*t. Any inputs appreciated. Not gonna go wild on this , but gonna make HIM PAY for any expenses!!!!!!

Little Sh*t HAS GOT TO LEARN SOMETIME!!!!!!

[TBK1]

OH forgot! his has the 4 speed, if we install the 5sp will the speedo gears interchange and will that keep the speedo acurate?

[jmark]

What happened? I'd check with Bill W.

[TBK1]

At japn auto bill? Good to see ya Jmark.

Wont get the details, you now boys "I SWEAR I WASN'T DOING ANYTHING DAD"

[jmark]

At japn auto bill? Good to see ya Jmark.

Wont get the details, you now boys "I SWEAR I WASN'T DOING ANYTHING DAD"

Ya Japanese Auto Bill.

[Arne]

OK. First, berfore I forget, the speedo gears should interchange.

Second, the Webers and associated parts should bolt straight on. I have put SUs and their manifolds on my L28, which was out of an '83 ZX and has a P79 head. No real issues.

Third, a compression test may not confirm anything. It will tell you that the valves and top two rings (compression rings) are sealing, but won't tell a thing about the bottom rings which only do oil control. The L28 currently in my car has great compression: 165-170 in all six holes. It also burns oil badly, enough that I had to go two steps hotter plugs to keep it from fouling plugs until I get my L24 rebuilt.

So if your L28 has a fresh head, I'd guess the oil control rings are bad. (The spreader rings have probably lost their tension.) Probably time to refresh the lower end.

[280~Master]

Ok, the 77 sounds good due to the fact that it has N47 head, diamond ports on it with steel sleeves seems to have less power for him to destroy it.

The compression test will tell you if you need new rings in it, by doing the old add a tea spoon of oil to the cylinder trick. Help here guys!! The RUM is kicking in.

I think adding a spoon full of oil should tell you if the oil ring is bad. Am I right fellas??

For instance if you run a compression test and it runs low and you add oil to the cylinder you are testing and it runs high then you need to rebuild the bottom half. At least the rings will need to be replaced in this case.

I for one would give my son the N47 head with Fuel injection and keep the E88 and carbs for my car. The fuel injection should convert right over if you use the 77 motor. You just have to place the computer in a spot.. On the driver left under the dash is stock for the Z car. The wiring for the fuel injection is not connected to the chasy wiring at all on the car. They are run on opposite sides of the car. Motor on left and electric on right.

The blocks should all be about the same with everything inter changing. Just watch out for the head gasket you buy. Do research on this for I don’t remember which on is better.

As far as paying for this I would charge him for a new motor in one of the cars.. Say about 1500.00……..

[Dtsnlvrs]

That settles it, when I retire form the service, I am going to open a Z shop in upstate SC...hows "Anderson Z" sound??? Or if I can get permission from Doug Smith in Tacoma...."Fairlady Motors East"

[TBK1]

Getting ALOT of great info/ ideas here, keep them coming, right now Im not doing anything, gonna let him think about it awhile!!!!!!!!!

"Flight Engineer", is that the same as "CHAIRBORN" , just kidding I'm retired USAF myself 12 years now.

[deedee]

I have an L26 motor and I'm going to get another head for it and was wondering what L24 head would be better for my motor. What should I use and which one should I stay away from?

DeeDee

[Arne]

I'm not sure you have much to gain on an L26 by going to an earlier head. The E31 ('70-71) and small-chamber E88 ('71-72) will give a bit more compression, but have smaller intake valves. The large chamber E88 ('73) will give about the same compression and still have smaller intake valves.

If I were looking for performance, I'd probably look for an N42 ('75-76 L28) instead. That would keep the same compression as stock (more or less), but have bigger exhaust valves too. Still has square ports, so no manifold change is needed. If it hasn't had them replaced already, the exhaust seats should be replaced with steel seats when the valve job is done.

[nwcubsman]

Check the exhaust ports on your N47 head. If they are round ports, your existing exhaust system won't fit from the E88, L24 head. The E88 has rectangular exhaust ports. If you have the exhaust manifold to go with the L28, it isn't much of an issue.