My head grew longer and the *new* manifold doesn't fit?

joefarmer

joefarmer

MR. Supreme Overlord
Slightly confused here. Either my caliper is lying or my CR head is expanded between exhaust ports 3-4? The stainless manifold that I obtained doesn't seem to match the head's port or bolt pattern?

CR head measurements:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	80.35mm	39.99mm	    120.34
2-3	79.98mm	40.03mm	    120.00
3-4	79.92mm	40.02mm	    119.94
4-5	81.10mm	40.00mm	    121.1
5-6	80.91mm	40.00mm	    120.91

Stainless manifold:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	77.36mm	41.93mm	   119.29
2-3	77.31mm	42.04mm	   119.35
3-4	74.59mm	42.02mm	   [B][color="#cc0000"]116.61[/COLOR][/B]
4-5	77.18mm	42.02mm	   119.2
5-6	77.29mm	42.08mm	   119.37
 
I think someone on here said they had to drill stainless's holes out for theirs to fit, bad casting.
 
My stainless manifold on my stock 2nd gen head was an absolute ***** to get the bolt holes to line up on. Basically I had to put all the bolts in by only one or two threads so I could wiggle it enough to get the 3-4 holes in.
 
If it doesn't fit, send it back to me. I don't want to sell something that doesn't fit. I Bought it from Cummins Performance Parts. He may have come across this before and have a procedure in place.

RonA
 
Just for future reference the bolt holes on 3&4 are smaller and are supposed to be installed first to line up the rest of the holes.
 
RonA said:
If it doesn't fit, send it back to me. I don't want to sell something that doesn't fit. I Bought it from Cummins Performance Parts. He may have come across this before and have a procedure in place.

RonA
Click to expand...

No way man! It's MINE!!! LOL

GRotman said:
Just for future reference the bolt holes on 3&4 are smaller and are supposed to be installed first to line up the rest of the holes.
Click to expand...

Not a problem. If I can remember this when I finally go to install it, I'll be happy!
 
How big are the bolt holes? Thats an 1/8" difference between head and manifold bolt spacing. Sounds like a good time to break out the die grinder, instead of side loading the bolts and peeling the threads off them.
 
Tate said:
How big are the bolt holes? Thats an 1/8" difference between head and manifold bolt spacing. Sounds like a good time to break out the die grinder, instead of side loading the bolts and peeling the threads off them.
Click to expand...
Ah ha! All holes are drilled 12.5mm instead of 10.5mm or even 11mm. An extra 5mm hole spacing would account for the 3.4mm off-spacing. Mystery solved.
 
You actually only have 2.5mm extra room, from edge of hole to center. Not enough to make up the 3.4mm you're missing. All the other numbers will also be out, as referenced from a single cylinder, as I have illustrated below. Almost 3/8" out from 1-6!:doh: Looks like some shoddy machine work to me.

CR head measurements:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	80.35mm	39.99mm	    120.34
2-3	79.98mm	40.03mm	    120.00
3-4	79.92mm	40.02mm	    119.94
4-5	81.10mm	40.00mm	    121.1
5-6	80.91mm	40.00mm	    120.91

Stainless manifold:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	77.36mm	41.93mm	   119.29
2-3	77.31mm	42.04mm	   119.35
3-4	74.59mm	42.02mm	   [B][color="#cc0000"]116.61[/COLOR][/B]
4-5	77.18mm	42.02mm	   119.2
5-6	77.29mm	42.08mm	   119.37

CR head measurements:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	80.35mm	39.99mm	    [B]120.34[/B]
1-3	79.98mm	40.03mm	    [B]240.34[/B]
1-4	79.92mm	40.02mm	    [B]360.28[/B]
1-5	81.10mm	40.00mm	    [B]481.38[/B]
1-6	80.91mm	40.00mm	    [B]602.29[/B]

Stainless manifold:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	77.36mm	41.93mm	   [B]119.29[/B]
1-3	77.31mm	42.04mm	   [B]238.64[/B]
1-4	74.59mm	42.02mm	   [B]355.25[/B]
1-5	77.18mm	42.02mm	   [B]474.45[/B]
1-6	77.29mm	42.08mm	   [B]593.82[/B]
 
Tate said:
You actually only have 2.5mm extra room, from edge of hole to center. Not enough to make up the 3.4mm you're missing. All the other numbers will also be out, as referenced from a single cylinder, as I have illustrated below. Almost 3/8" out from 1-6!:doh: Looks like some shoddy machine work to me.
Click to expand...

I wasn't even thinking of end to end length. Also, I don't profess incredible dial caliper skills either. I was showed a used head last night that has the soot marks indicate where the manifold didn't match up to the exhaust ports. The soot is on the outsides of the port on the 3-4 and on the inside of 1-2-5-6. I suppose I could port match to the stainless manifold since it's only a few mm either direction and the ports are larger on the stainless.

The good news is that I've never seen one of these crack or had any other issues with them.
 
RAMICATOR said:
Are you beening a wise azz or just dumb. at least 7 times "stainless" was mention in this thread. Twice in the first post!
Click to expand...

There are a few companies that carry stainless steel manifolds,
I can understand his confusion.
Lighten up
 
joefarmer said:
I wasn't even thinking of end to end length. Also, I don't profess incredible dial caliper skills either. I was showed a used head last night that has the soot marks indicate where the manifold didn't match up to the exhaust ports. The soot is on the outsides of the port on the 3-4 and on the inside of 1-2-5-6. I suppose I could port match to the stainless manifold since it's only a few mm either direction and the ports are larger on the stainless.

The good news is that I've never seen one of these crack or had any other issues with them.
Click to expand...

I'd be a bit surprised to see the head actually have 1.5mm difference on bolt spacing. I'd say measure from 1 to 6 with a tape, should be damn near 600mm. If the holes are as far out as you measured though, you'll still need to break out the die grinder for half of them. Or that would be my solution, at least.
 
joefarmer said:
Slightly confused here. Either my caliper is lying or my CR head is expanded between exhaust ports 3-4? The stainless manifold that I obtained doesn't seem to match the head's port or bolt pattern?

CR head measurements:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	80.35mm	39.99mm	    120.34
2-3	79.98mm	40.03mm	    120.00
3-4	79.92mm	40.02mm	    119.94
4-5	81.10mm	40.00mm	    121.1
5-6	80.91mm	40.00mm	    120.91

Stainless manifold:
Code: 
[B]ports	space    portsize    combined[/B]
1-2 	77.36mm	41.93mm	   119.29
2-3	77.31mm	42.04mm	   119.35
3-4	74.59mm	42.02mm	   [B][color="#cc0000"]116.61[/COLOR][/B]
4-5	77.18mm	42.02mm	   119.2
5-6	77.29mm	42.08mm	   119.37
Click to expand...

GRotman said:
Just for future reference the bolt holes on 3&4 are smaller and are supposed to be installed first to line up the rest of the holes.
Click to expand...



That is correct. Line 3 & 4 up first. In the casting process, any foundry warns of mold shifting + or - .030". This is a problem that any and all castings must deal with. It is up to the machinist to check all clearances before sending them out the door. Johnny is pretty good at keeping these guys straight, but he also guarantees fitment. If there is a problem, I'm sure he wont have a problem sending out a replacement. I've never seen him not stand behind his product 100%.
 
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