New thrust washers as well. NEVER reuse any bearing surface. Make sure
your valve springs won't bind with the new cam, and verify (mic)
piston/valve clearance. Definitely balance the flywheel as Brian says.
------------------------------------
> >
> >I've decided to rebuild my 1275 instead of buying a already rebuilt
unit,
> >(Thanks Skip and everyone else who helped me with that decision) So now
> >I'm wondering about a few different add-on/mods and their relative
value.
> >
> >The first is the engine rear seal from MinaMania, has anyone tried this
> >and is it worth the $200? I heard it doesn't work with the 5 speed
datsun
> >tranny, which is fine with me as I'm rather fond of my stock tranny.
>
> I've not tried this, but then again I've not had problems with the stock
> scroll seal. For $200, i'd probably think about it, or make an
equivalent.
> Depends to some degree on the amount of machining required, and how much
you
> trust your machine shop to get it right...
> >
> >The second would be a high lift rocker setup, not the roller bearing
type,
> >but the cast MiniSpares version. Vizard gets all gushy over these in his
> >book, are they worth the extra expense? I'll be putting in a slightly
hot
> >cam, the head is pretty stock, the carb is a Weber DGV, and the exhaust
> >mainfold is a LCB header.
>
> The cam and the rockers have to be matched to each other, so if you get a
> cam designed to be used with the high lift rockers, go for it. If your
> chosen cam is designed to run with stock rockers, then check out how much
> lift you'll be getting, and think about valve clearance, valve spring
crush,
> and so on. Things to note - Plain bearing high lift rockers tend to wear
> their bushings fairly quickly, and can put weird loads into the
rockershafts
> in some cases. We broke at least 6 rockershafts before we got the new
> thickwall shafts in, and then the problem went away. I'd probably go
with
> the high lift, low duration type of cam setup, to keep as much low rpm
> drivability as possible.
>
> >
> >I plan on all new pistons, tappets, pushrods, reground and balanced
crank,
> >new radiator, oil pump, water pump, bearings, and high grade bolts
throughout.
> >Is there anything I'm missing? (the clutch is 6 months old, so I'm
leaving
> >it be)
>
> Try Omega pistons - the rings are the highest quality I've ever used.
I've
> never changed a pushrod that wasn't bent yet - why change them? The
bolts
> are a great idea - I use ARP in every thing critical, and go up 20% on
the
> torque specs. These bolts need to be torqued with the correct lube on
the
> threads and under the heads - talk to the manufacturer's tech support
line,
> not the distributor, if you have any questions. And speaking of
> distributors, if you're going this far, why not get an Aldon type, or
> equivalent, new distributor if yours is worn at all? I never have cranks
> balanced - the stock balance is pretty good - but I do get new flywheels
> balanced, especially if they're lightened at all.
>
> Finally, if you're going to an aftermarket cam, you should seriously
> consider an adjustable cam timing gear, and time the cam in to specs.
It's
> not hard, needs about $25 worth of dial indicator and magnetic stand, and
> can be critical to ensuring that the engine runs the way it should. When
> cams are reground, sometimes the grind requires that the lobe centers get
> moved around, so the original timing is lost. The manufacturer expects
that
> you'll time it in correctly, and often furnishes a nice protractor to
> encourage you...
>
> If you go with new valve springs, get top caps to match, and only use
steel
> top caps. The pretty green aluminium ones have a bad habit of getting
> nicked, and then shattering, causing dropped and bent valves, wiped out
> valve seats, and pistons with holes in them. I have such a valve (1.218"
> rimflow exhaust valve, to be precise) on my desk as a reminder.
>
> That's enough for now - have fun! Brian
> >
> >TIA,
> >
> >Robert Weeks
> >Durham NC
> >1969 Midget
> >http://www.woozy.com/midget/
> >
> >
> >
>
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