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> Bus heads?, Intake manifold bolt spacing
ThePaintedMan
post Aug 25 2013, 10:30 AM
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Hey guys,
Just finishing up the prep on getting my spare motor back in the car. Came across something a little "fishy". So, I swapped over just about everything that was on my 1.7, and this engine is *supposed* to be a 1.8. Everything fits just fine, except for the intake manifolds and gaskets. There are 4 intake manifold studs, but the outer studs are about 3/8 inches further apart than on the 1.8. So much so, that the new 1.7/1.8 phenolic spacers that I have do not fit over the studs. I noticed that the previous owner had cut the spacers in half to make two separate pieces, for each intake port. They still didn't fit quite right though, and part of the spacer protrudes into the intake hole/bore.

I'm wondering if these are some kind of other Type 4 head, perhaps from a bus? Pictures to follow in a moment...


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euro911
post Aug 25 2013, 11:07 AM
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Can you post the # on the heads? (gotta pull the tins back off) (IMG:style_emoticons/default/dry.gif)

What's the part #s on the intake manifolds?
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ThePaintedMan
post Aug 25 2013, 12:52 PM
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Hey Mark...

Where are the casting numbers on the heads, when I pull them off?

These are (I believe) CB Performance manifolds - for a dual carb setup. The manifolds worked fine on my other motor. As did these manifold spacers (from Pelican).
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Dave_Darling
post Aug 25 2013, 01:27 PM
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I think the casting numbers are in the rocker box.

--DD
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ThePaintedMan
post Aug 25 2013, 01:28 PM
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It was under the valve cover, not the engine tin.

022-101-372, which, according to :

http://www.tunacan.net/t4/reference/cylhead.htm

is a 1.7 head. This engine is supposed to be a 1.8, but that doesn't matter to me. I'm just curious why the dimensions of the studs are different than my 1.7.
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ThePaintedMan
post Aug 25 2013, 01:34 PM
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That site also lists 022-101-372G as a 2.0. I couldn't see a "G" on the casting number for these heads, but I suppose it's a possibility. And the 2.0 bus heads are supposed to be four bolts as well.

Unfortunately that doesn't really help with the dimensions though.
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euro911
post Aug 25 2013, 01:39 PM
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That's weird (IMG:style_emoticons/default/blink.gif)

(IMG:style_emoticons/default/confused24.gif)
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ThePaintedMan
post Aug 25 2013, 01:45 PM
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I know, right? Raby would know this one for sure.

I suspect they must be Bus heads. The three types of carb manifolds I have seen from CB Performance and various other manufacturers all have the outer holes elongated that seem to make up for this difference. Unfortunately the phenolic spacers do not. Had I known that they were bus heads, I could have ordered the correct spacers weeks ago. (IMG:style_emoticons/default/headbang.gif)
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type47
post Aug 25 2013, 01:47 PM
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How about the alignment with the holes on the intake manifold? (seems to me that's what matters)
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ThePaintedMan
post Aug 25 2013, 01:52 PM
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The intake manifolds line up fine, from what I can tell. As I stated, they came pre-drilled, it seems, for both dimensions. I.e. the outer holes in the manifolds are elongated as if they were intended for dual-uses.
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ThePaintedMan
post Aug 26 2013, 11:46 AM
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Well, I ended up installing them as-is with a gasket on both sides of the spacer. I'd still like to know what the difference is here and why the dimensions on these heads are what they are, but for now, hopefully it'll do.
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euro911
post Aug 26 2013, 12:19 PM
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QUOTE(ThePaintedMan @ Aug 26 2013, 10:46 AM) *
Well, I ended up installing them as-is with a gasket on both sides of the spacer. I'd still like to know what the difference is here and why the dimensions on these heads are what they are, but for now, hopefully it'll do.
Krusty should be able to answer the question ...

PM him if he doesn't pop in on this thread (IMG:style_emoticons/default/confused24.gif)
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JamesM
post Aug 26 2013, 12:57 PM
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QUOTE(ThePaintedMan @ Aug 25 2013, 11:52 AM) *

The intake manifolds line up fine, from what I can tell. As I stated, they came pre-drilled, it seems, for both dimensions. I.e. the outer holes in the manifolds are elongated as if they were intended for dual-uses.



I thought the outer hole elongation on the manifolds was to cover the difference between the outer bolts to work with both the 4 bolt and 3 bolt setups. I had no idea there were 2 different spacing of 4 bolt heads?
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skeates
post Aug 26 2013, 01:10 PM
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Was the mis-match the same on both heads? Could be that one of the studs pulled and the PO installed a crooked helicoil?
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Cap'n Krusty
post Aug 26 2013, 01:21 PM
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I have seen ONLY one 4 bolt intake manifold bolt pattern and one 3 bolt intake manifold bolt pattern on T4 heads, be they T2, T4, or 914. Lotsa heads over 40 years, no variations on the 4 bolt pattern. The Spanish heads, all for 2 liter bus, are the same, too.

The Cap'n
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euro911
post Aug 26 2013, 01:31 PM
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QUOTE(skeates @ Aug 26 2013, 12:10 PM) *
Was the mis-match the same on both heads? Could be that one of the studs pulled and the PO installed a crooked helicoil?
I was thinking similar when I saw the pix George posted, ("The tins fit normal - what would be the difference?")

George, did you snap any pix of the intake ports without the gaskets? Is there any evidence that the original studs may have been relocated (possibly to fit some oddball intake manifold somebody kludged together)?
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euro911
post Aug 26 2013, 01:33 PM
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QUOTE(Cap'n Krusty @ Aug 26 2013, 12:21 PM) *
I have seen ONLY one 4 bolt intake manifold bolt pattern and one 3 bolt intake manifold bolt pattern on T4 heads, be they T2, T4, or 914. Lotsa heads over 40 years, no variations on the 4 bolt pattern. The Spanish heads, all for 2 liter bus, are the same, too.

The Cap'n
I've seen different exhaust ports, but not intakes.
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Cap'n Krusty
post Aug 26 2013, 01:55 PM
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Yup. "Race track" looking exhaust ports and "square" ports (78 and up T2s and Vanagons).

The Cap'n
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ThePaintedMan
post Aug 26 2013, 02:04 PM
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Yeah I knew about the square exhaust ports on the Vanagon heads, but not the intakes.

Both heads were the same (had the exact same dimension). I did see some welding on the backside of the intake stud (i.e. down in the fins area), but nothing blatantly obvious suggesting that it had been helicoiled before. Of course I was in too much of a rush to snap more pics. (IMG:style_emoticons/default/headbang.gif) The intakes that came on the engine are a little odd. They're very short and used bolts instead of studs, so I guess it is possible the PO decided it would be easier to fill in the original stud holes, then re-drill it for these manifolds? (IMG:style_emoticons/default/confused24.gif) They definitely weren't helicoiled though.

I got the engine from billh1963 off of that purty pink car with the flares he had sitting in his driveway. I don't think he knew much else about the history of the car, other than the engine had been rebuilt at some point.
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r_towle
post Aug 26 2013, 08:11 PM
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Could be the 2.0 liter heads that someone removed the middle stud and added two studs to match the manifolds.

I believe the outer studs on a 2.0 liter are wider in spacing than either the 1.7 or 1.8 heads.

Rich
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