'84 1200 engine for a '82 GW

[canuckxxxx]

Well I've saved lots of empty All Bran boxes. But I need head gaskets, some dowel pins, and o-rings.

 

[slabghost]

I plan to buy the copper head gaskets next time I buy them. But I have no intent to keep the 1200 heads.

 

[canuckxxxx]

You can buy copper head gaskets? :shock: :shock:

 

[slabghost]

Yes you can ekvh posted the link in one of the threads here. I thought I'd bookmarked it but I can't find it at the moment.

 

[ekvh]

Coppergasketsunlimited. I contacted Lani Visconti at [email protected]

He can do several thicknesses so if you want you can bump the compression a little. They were $55, I think. Cheap.

 

[Denver]

Your gonna love that fuel pump, :yes: mine were a little more than $20 each,a very good price from Rock Auto. :good:

 

[brianinpa]

canuckxxxx » Wed Jan 04, 2017 11:02 pm[/url]":1zaej46n]
Well I've saved lots of empty All Bran boxes. But I need head gaskets, some dowel pins, and o-rings.

I thought you meant gaskets for the carb

 

[canuckxxxx]

Well I finally got my gaskets, Orings and a couple of block-to-head dowels :Egyptian: . I tracked my order from Partzilla to Albany, NY on December 30 where it said it had been handed over to Canada Post. CP tracking has shown it in Albany since then. I thought maybe it was stuck in customs. Anyways today I got it...CP tracking still shows it in Albany. So much for tracking. :shock:

So now I have to remember what I am doing and get this thing put together. Sure hope these 1200 heads work well.

Brian

 

[canuckxxxx]

While waiting for my stuff I have been playing around with these 1200 heads. I like smallish intake ports because I think they match up with my single carb manifold runners which are only about 1 1/8" ID. Also I figure the combustion chambers are designed to match the piston tops. So I will go with the 1200 heads.

But there are a couple of things I worry about. The cams and their rockers that have a couple of lobes with some wear marks. And there is some doubt about how well the hydraulic valve adjusters will work. So, just for the heck of it I took the cam and rocker assembly off my 1100 engine that is now sitting in the corner of the garage. The cam fits fine into the 1200 head but when I put he 1100 rocker assembly on and tighten it down the cam is locked and will not turn. Seems like the cam bores of the head and rocker assembly do not match up perfectly. So I took the two dowels out that fit the rocker assembly to the head and put it back together. Now the cam turned freely. Do I really need the dowels? :headscratch:

BTW the 1100 rockers seem to line up with the tops of the valve stems.

Brian

 

[joedrum]

hmmm im thinking the oil passages dont line up to get oil to the rockers ...im thinking i look at that and that was the case ....been awhile and my memory is the biggest liar about me LOL

 

[dan filipi]

Me too, if I remember the 1200 and 1100 cam holder doesn't fit up to the oil feed swapped either way.

 

[slabghost]

There is also the question of will the valves hit using the 1100 cams. Why not just enlarge the relief on the pistons and use the 1100 heads?

 

[dan filipi]

I looked at the 1200 and 1100 cam holders, very different oil feed against the head side.

 

[canuckxxxx]

i agree the oiling would need to be modded. On the 1200 head the oil feed comes through from the block to a point below the base of where the 1100 rocker assembly ends up. You would have to block that exit point with a threaded plug. Then you would have to drill from the base of the centre, top rocker assembly bolt, to the oil feed passage. You could thread that hole for a plug to so you would have the option of using either 1100 or 1200 rocker assembly.

Brian

 

[canuckxxxx]

Here is a shot that shows where the oil feed goes to the base of the top centre bolt.

image

• canuckxxxx
• Jan 10, 2017

 

[canuckxxxx]

That is the 1100 head in the picture

 

[slabghost]

So what is the plan? Fit the higher lift 1100 cams in the 1200 heads after rerouting the oil? Should give it a little better performance over stock.

 

[canuckxxxx]

A couple of things are holding me back: not using the dowels seems wrong although I can't see why...but those dowels must be there for a reason. Maybe the rocker assembly would move around a bit, relative to the head, doing damage to itself. I'm thinking of taking it over to my machinist friend and see what he can come up with.

Would be interesting to see how it would perform with higher lift, shorter duration 1100 cams. Should have lots of low and midrange torque, which I value. And, like Joe, I like the simplicity of the mechanical rockers.

Brian

 

[joedrum]

im thinking the 1100 head with the bigger intake valve will not hurt anything at all much ...are you worried about doiing some piston relief ?

 

[canuckxxxx]

No, I'm not worried about the valves hitting because I had the 1100 heads on, and ran it so I know that is OK.

I think there are benefits from the 1200 combustion chamber and the smaller ports for a high torque engine. Like I said before, going from 1100 to 1200 is a 9% increase but HP went from 82 to 94 which is a 15% increase. So I figure there must be something good about those heads. I may be wrong but I want to give these 1200 heads a try.

Brian