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I want bigger valves for this setup, right?


sneax

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The Clevite NDG bearings are the one I wanna use, right? - Correct

 

What is meant by de-burring? - Grind off any sharp edges. At the bottom of the bores, the sides of the main bearing saddles, etc.

 

For the flywheel I read about the aluminium 280z flywheels... or can I machine down my original one? - Either is good.

Lighter balancer as well? can I machine it as well? - Lighter than what? The stock one isn't a balancer at all, but if you wanted to use a 240Z style balancer and water pump/pulley, you could do that. Other vibration dampeners are available, but the original Nissan Motorsports style is the coolest. It will give that vintage vibe (no pun intended). Rebello should have a line on one of those for you.

 

 

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OK - I did not know about the pistons for those rods! are they forged? for different compression rates or deck heights available?

can you give me a link where to find them?

 

And are the U60 and N85 rods strong enough... and light as well? I only red about the Z20 in long rods! Are they the same?

 

thanks for your help again!  :thumbup:

Yes, forged.

 

These are stock rods, and at your HP, the should last a long time, but forged are definitely better. It's just that you may need to do a bit of homework before you buy a specific length.

 

Any time.

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Get your new rods resized before having the crank ground.   Main studs/bolts and line hone done as well, then grind the crank to fit the holes.  

 

I don't know if you can still order a new points distributor from the dealer - I doubt it.  Find a dirty old core and I'll set it up for you.  Its my day job.  Great looking coupe by the way!  I hope for your sake you have figured out great ventilation for it or you'll be COOKED in Mexico!!!  MGAs are hot in winter driving!  Cool Suit?  

 

My build is here:

http://community.ratsun.net/topic/66750-620-land-speed-record/

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Measure the crank before you have it ground. If it's within spec, I would just have it polished. Race motors will need rebuilding and I prefer to save the grinding for later rebuilds.

 

With all the modern high performance oils out there today, bearing clearance can be set loose or tight and then chose the oil accordingly (to a point). The mains should be around .0022" -.0025" clearance and the rods around .0018" -.002". You can run less on both if you're using a good racing oil (Redline 30wt). You can also run it with more clearance, but I stop at about .003" on the mains. That gets to be too much and you start losing control over where the oil goes at that point.

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Ok - great information again! thanks guys!

I just followed what you told me - gave Dave Rebello a call !!! Looks like I get now all the head work done by Rebello!

Will cost more - but will save me a lot of trouble and I can be sure to get something solid!!

 

 

Get your new rods resized before having the crank ground.   Main studs/bolts and line hone done as well, then grind the crank to fit the holes.  

 

I don't know if you can still order a new points distributor from the dealer - I doubt it.  Find a dirty old core and I'll set it up for you.  Its my day job.  Great looking coupe by the way!  I hope for your sake you have figured out great ventilation for it or you'll be COOKED in Mexico!!!  MGAs are hot in winter driving!  Cool Suit?  

 

My build is here:

http://community.ratsun.net/topic/66750-620-land-speed-record/

 

Yeah - getting freaking hot in the car! I insulated the firewall and the floor, added a vent hose from the front and transferred the little triangle windows into air intakes! but still we drove with opened doors between the race stages ... haha  :thumbup: 

Just read half of your race car thread! WOW!

 

this is the distributor I got with my engine:

DSC_1072.jpg

DSC_1073.jpg

DSC_1075.jpg

DSC_1074.jpg

 

 

Is that the one you are talking about?

I guess this thing is getting me nowhere, right?
:blush:

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You're starting to sell me on the points ignition system (for vintage cars). Maybe next time I run into a problem with an older distributor, instead of masking the problem and installing a Pertronix, I'll give you the distributor to have you work your magic.

 

I just hate adjusting points...

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I'm curious do all of the L-series matchbox units have the ignition retard (by contrast the A series do not)

 

@Distributor guy will likely have to talk soon as I'm down to one good A-series distributor that runs well over 7800 rpms.

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The ZX and later Maxima E12-93 module does have a built in retard governed by the ECU. If you use it in place of an E12 80 module it will self retard as the engine revs. I think if you ground the two extra terminals this defeats it.The Matchbox E12 80 module has only the two terminals and does not retard with revs.

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I'm curious do all of the L-series matchbox units have the ignition retard (by contrast the A series do not)

 

@Distributor guy will likely have to talk soon as I'm down to one good A-series distributor that runs well over 7800 rpms.

 

I Likely have a bunch.  Off the top of my head I'd need a pic on the A-series to verify length and drop-in depth.  I do 4/6 cylinder L-series mostly, along with many other brands.  

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tomorrow I will finally start fitting my spare L20B into the MG ... while the race engine is at the machine shop.

 

I know that the engine sits in an angle tilted to the right! 
How do I determine the right angle? ...does the valve cover gasket sit straight?

 

does the angle really matter? in a range of 10 -15 degree? (besides the oil pan of course) I think it will get fucking tight on the left side with carbs, header and steering column!  :confused:

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ok - 12 degrees like the valves... so the valves end up vertical! weird! hehe

could I tilt it even more?

 

my gearbox is a 5 speed from a Z car... i think!     will post pics tomorrow!

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ok - 12 degrees like the valves... so the valves end up vertical! weird! hehe

could I tilt it even more?

 

my gearbox is a 5 speed from a Z car... i think!     will post pics tomorrow!

It really depends on what transmission you have for it, if it is an L block transmission then you would mount the transmission with the shift lever straight up in third or fourth gear and the engine will be tilted what it is made to be tilted, if it is a Z block transmission then you have a problem and you will have to find an L block transmission to bolt to your L20b block.

Another thing you will need to address is the clutch collar, if the Z car had the same clutch cover size as the L20b block/engine then you are good to go, but if they were different sized clutch covers you are going to need the collar for the clutch cover size you have on the L20b, the collar follows the clutch cover, not the transmission.

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He means Z series engine block transmission like from a 720. If it's a Z car it will have an L series engine and be ok.

 

LansZtrannybell002Large-2.jpg

 

L series transmission bolt pattern

 

 

LansZtrannybell003Large-1.jpg

 

Z series transmission bolt pattern. Using this on an L series engine will either tilt the shifter into the passenger's hip or force the engine to be about 8 degrees to the left of vertical not 12 to the right.

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Ok thanks...

 

The one gearbox that I have is an Z series - goin from the bolt pattern you posted!

I have been told that I can bend the shifter stick of that by 20 degree to the left and it would work.

But it would also mean the gearbox support mount is tiltet 20 degrees, right?

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That's exactly right.

 

You shouldn't have any problems mounting the engine or trans at an angle (other than 12 deg). You might discover something that the rest of us don't know. The only thing I can think of that may suffer (if you tilt too far) would be the valvetrain oiling, but you're probably going to run a spray bar anyway. The oil pan and pickup tube will obviously need some thought.

 

Back in the 80's, Electromative ran their L6 way over to one side.

 

If you're building an intake (I think you said you were), just make sure the carbs are flat-ish. They have wiggle room too, but float levels can get screwy when they are tilted too much.

 

And I would get a L series bellhousing for that Z series trans, or it will just add to the complexity of tilting your engine over.

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Ok - very good!

I will run a spray bar - Rebello is taking care of that as well!

I will have to see how it fits best under the hood of the MG! I know already that the crossmember is in the way big time so i will have to cut it to half the height! My sway bar is far to the front and no problem... About the rack & pinion steering I am a little worried... But relocating that is easy!

 

An L bellhouse might be not easy here in Mexico... What about the Datsun J engine 5 speed? Would that bellhouse do the job? ( i have a J engine in the MG right now with a 5 speed! But the output shaft is bend a thou and starts vibrating crazy at speed!)

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Spray bar & cam towers from a 260Z. No external lines/fittings to deal with.

 

DSC07747.jpg

 

L4spraybar3.jpg

 

Simple & works great.

Just don't use the early one with die cast junction blocks.

Late ones are stamped steel, and fully oven brazed together.

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Keep in mind the Z series is about 8 degrees to the left so it has to rotate nearly 20 degrees to the right to match the 12  degree L series engine. What you will find is the transmission center line will lift and shift to the right as it is rotated to match the 12 degree L series. You can't just slip a 20 degree wedge in there. The mount really needs to be lowered an inch or two before wedging.

 

Better to swap an L series 4 or 5 speed front case on it instead.

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