ryanill
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| posted on 27/12/12 at 04:18 PM |
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Pinto head ID
Hi all
Sorry to bring this up again. As I'm sure it's been a topic many a time.
I have searched the Internet for a while and carnt seem to find a definite answer.
I'm stripping the engine and now the head is off iv noticed that the inlet ports are cam shaped with the lobe at the top and that the top of
that lobe is dished in a bit. Also looking at the valve stem guide it looks like it tapers in to the valve stem and is generally a lot tidier that
other heads iv looked at. I can still feel quite a sharp turn in on the short side radius of the inlet and all the inlets and outlets ports are as
cast . Also putting a rule into the bottom on the inlet to gauge the angle of the inlets doesn't seem to be a reader angle as I head the
injection heads have ( it comes out almost 90 degrees to the inlets gaskets face)
Iv looked for letters near the number 4 spark plug but carnt see any. I got a bit of fine emery paper just to lightly tidy up the surface round
sparkplug but still found nothing is there any serial number or anything like that on the head I could check and get a definite answer ?
Ryan
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snapper
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| posted on 27/12/12 at 04:28 PM |
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Sounds like an injection head
Non injection shortside turn is a sharp angle injection heads whilst still a sharp turn are smooth
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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ryanill
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| posted on 27/12/12 at 04:36 PM |
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Is there a way of telling for sure ?
I know the injection heads are better for a few HP over the standard but I didn't realise I potentially had one. And have spent quite a bit of
time porting and having a leaded head sorted out having it skimmed ( no hardened seats just planed to run with additive) if I do indeed have a
unleaded head what would be best to do or is it just personal preference ?
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Peteff
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| posted on 27/12/12 at 05:31 PM |
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Injection heads have the oval inlet ports and carb ones are round so you have an injection head which should run unleaded fuel without any additives
or problems.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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snapper
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| posted on 27/12/12 at 06:02 PM |
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For most Pintos just large inlet valves with 3 angle seats throat widened at the seat will be all you need to do
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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ryanill
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| posted on 27/12/12 at 06:23 PM |
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Ok well so far the carb head has even ported and the valves guides trimmed down the throats have been opened out to the edge of the seats. No mods to
the seats ( other that lapping in) but a bit of reshaping to the valves themselves.
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chillis
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| posted on 27/12/12 at 08:48 PM |
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Only a few 2.0 pinto heads had hardened valve seats back in the '70's Injection heads have a better port shape and better water flow
around the ports but no hardened seats. Almost all the 2.0 test heads failed the durability tests so only the 1.6 had them from 1990.
I'll look up my notes when I get back to work to see what the head part numbers are. They'll start 84.....
Never under estimate the ingenuity of an idiot!
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Dusty
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| posted on 28/12/12 at 01:42 AM |
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There should be a letter(s) stamped on the machined surface of the exhaust face near plug 4. Picture shows an R on my old one. Inlet ports
'cam' shaped as opposed to round also confirms it is unleaded.
[img]
 
Unleaded heads
[/img]
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ryanill
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| posted on 28/12/12 at 07:45 AM |
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Cheers dusty Iv checked that area on the head and there is nothing there. Must have worn off or something.
Ok chillis if the head matchs the block then the head would be from an late 88 car. Any info you have would be great.
What's people's honest opinion as to witch head to use. I'm not fussed about using additive to be honest. And my plan was to use the
carb head witch has a 40 thou skim the valve thoughts have been opened to 1.5 inch ( 38.1mm) as I'm running CVK 38 bike carbs . Also the stem
guides have been shortened and the short side radius have been given the smoothest radius I could. All the combustion chambers have been CC'ed
and balanced. And the valves themselves have been reshaped a bit ( made the transition from the seat face on the valve to the actual valve stem has
been smoothed)
The outlet ports have been gasket matched the valves throughts opened up and all the sharp edges removed from the stem guide but kept the length to
aid heat disapation.
The rest of the work to the head will include a new inlet manifold the fits the bike carbs directly to the block and fitting a FR 32 Kent cam and
vernia pully.
That was the plan for the carb head will that head still out prefor the injection head as it is ?
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