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Pinto injection head identification


LewisH

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I've just bought an engine to replace my lackluster 185 pinto and trying to establish if the head is an injection type. I've heard that the inlet ports are egg shaped on injection, but I'm not sure if mine is or not...I'm hoping it is, but not sure if I'm trying to convince myself that they are oval shaped or not? 

Can anyone help identify this? Are these oval or am I going cross-eyed?

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Edited by LewisH
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As Bob says, they don't look like standard injection ports but it might be an injection head which has had the inlet ports opened up. There is a hint of a pointy top to them.  There should be some letters stamped near No.4 exhaust port and somewhere on here there is a list of what they mean.  Sorry but I don't know exactly where, you'd have to do a search.

Steve

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Ah okay. If I run my finger around the top of the inlet, there is a noticeable profile change on all of them, but the inside of the ports are still rough, so it doesn't look like it's had any porting done from what I can tell. 

The head is stamped with P. As I understand it, this just means that it is unleaded? I can't seem to find any information that denotes an injection head other than oval ports and I would agree from looking at Bob's picture, my head is not pronounced enough in shape...just a bit pointy for some reason. 

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A non-injection head has round inlet ports so there should be no noticeable profile change. If you measure the diameter of your ports it will tell you if they've been enlarged - I think a standard port is just less than 40mm (ignoring the pointy bit) but I haven't got one handy to check so I'm going off memory which is not so reliable these days.  I had an injection head, opened up to 45mm for 45DCOE Webers and the ports looked a lot like yours, as I remember.  If Bob still has the head in the picture he might be able to measure it for you.

You'll find that a lot of people leave the ports rough when they re-work them as it is supposed to help keep the fuel atomised (whatever that means)!

 

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I've had a quick "Google" and a search on here but I can't find a measurement for a standard port.  Someone on here will know I'm sure, but 37mm does sound about standard size.

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I have a copy of a Pinto tuning guide, in the guide there is a part about the inlet ports, it reads as follows :-

The 36 to 38mm port diameter of all 2000 cylinder heads is optimally sized just as it comes from Ford and does not need to be opened out at all. In fact, it can be left in the as-cast state. The largest standard port size (38mm) is as large as the largest carburettor choke (38mm) that is normally used on a well modified 2000cc/2100cc engine. None of the Pinto cylinder heads, if fitted to their original block, really need to have their inlet ports opened out.

 

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A simple test is to shove your finger down the inlet port and feel the short side turn, non- injection you will feel a sharp edge, injection has a smooth edge/transition to the seat. If you can feel a slight cut out at the manifold face top of the port and it has an unleaded stamp it is most likely an injection head.

whilst it is true that Pinto heads are large and don’t need opening out they do need a lot of work to make big power, mostly around the valve end and the valve guide boss.

port matching the head to the inlet manifold is a relatively easy mod.

unshrouding the valves where they get close to the chamber walls if fitting big valves.

compression increase by skimming head depending on what carbs and cams you are using.

mig you put a non-injection head and an injection head side by side it’s obvious which is which.

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Thanks for all the info, very helpful. 

The ports have a sharp edge so must be a standard head, so I'll look at getting some head work done to improve gas flow. I've seen this priced at around £400 by pinto 'specialists' online, does this sound about right?

I don't have a bucket of money to spend, especially as we now have our first rugrat on the way, but I'd like to eek out as much as possible from this engine before it goes into the car. Is it worth going up to 2.1? 

I was thinking of doing a basic refresh (bearings and seals), porting the head and fitting an uprated camshaft. Engine came with ZX6R carbs and manifold but running on luminition. Hoping to keep the spend under 1k. 

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Here is a link to free copy of the powertune manual, you can view online or download the pdf, it might be of help when you are considering what to do with your engine and converse with the pintp "specialists".

https://procarmanuals.com/how-to-power-tune-ford-sohc-4-cylinder-pinto-cosworth-dohc-engines/

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