ZCar Forum banner

Status
Not open for further replies.
1 - 6 of 6 Posts

·
Registered
Joined
·
651 Posts
Discussion Starter #1
Now that my '72 240 is in the garage for the winter, I'm going to make a few improvements so here's a couple questions:

The head. Since I have a gasket leak, I'm going to pull the head off. Should I assume it will need to be machined (warpage)? And how do I check whether it's too warped? Also, Motorsport used to sell rebuilt heads with trade-in, anyone know if they still do and is it worth it.

The cam. Any recommendations for a camshaft? I want to improve power through the mid rpm range, 3000-5000. But I want to have a good enough idle to not foul plugs too fast.

Intake manifold. I'm running stock roundtops. How do you polish the manifolds? Is there a tool designed for use on an electric drill or something like that?

Headers. Done, sounds awesome!

Thanks for your help, SoM
 

·
Registered
Joined
·
181 Posts
hehehe

you could use the parts out of an echo... I hear those things are pretty nasty!

Sorry, man, I couldn't resist. :)


Shayne
 

·
Registered
Joined
·
651 Posts
Discussion Starter #3
oooh, that hurts

that's an echo from the past...
 

·
Registered
Joined
·
1,760 Posts
Re: oooh, that hurts

I think Motorsports still have the rebuilt heads available on exchange basis. Sounds like a good deal. Call around to some machine shops and get prices for a head overhaul. Will probably be more that what Motorsports is charging. The downside to the MS head, you are stuck with the stock cam. Yes, if you are just changing the head gasket, take the head to a machine shop and see it the head is warped. If it is, they can shave it for you.
 

·
Registered
Joined
·
1,713 Posts
Definitely...

Check out head for warpage (requires precision 30" straightedge). Also recommend having a machine shop do liquid dye penetrant test for cracks. No point sinking money into head w/ cracks (my opinion).

If the heads in good shape, then you should figure on springing the $200 or so for a good head overhaul w/ valve grind, valve guide check-up, plus gasket set and valve stem seals. Nissan or Felpro gaskets both register OK per the archives. I'm into OEM, but the gasket set is about $150 and Felpro is much cheaper.

You don't want to polish the intake manifold internal passages - take out major bumps, yes, but leave surface rough to promote turbulent flow and good fuel mixing. Port matching should help quite a bit and isn't difficult. Porting and polishing is very demanding and highly technical. Guys like Rebello charge over $1k for a race ready port and polish job.

My experience w/ cam was that I simply could not get it to idle and stay running below about 1200 rpm. Did not have trouble w/ fouling - that is carb mixture thing.

Later!
Al
 

·
Registered
Joined
·
651 Posts
Discussion Starter #6
Re: oooh, that hurts

Yeah, my old catalog ('95) says only the stock cam. New catalog in the mail. Old one says it's with resurfaced valve seats and some other clean up etc.

I know the new cam will be extra, but which one?
SoM
 
1 - 6 of 6 Posts
Status
Not open for further replies.
Top