Thread: Exhaust Manifold +08
01-09-2014, 10:00 PM #1
Exhaust Manifold +08
Can someone explain the difference between an 08+ manifold and the older model... I'm curious and can't find pictures or difference except that's is easier to drill the hole...
My manifold is drilled but thread is bad... Already have some solutions but I was wondering about the differences...
01-09-2014, 11:05 PM #2
01-09-2014, 11:09 PM #3
Basically the water passage on the pre 08s is somewhat closer to where they drill for the O2 sensor. If your not perfect center it will leak and damage the sensors.
01-10-2014, 04:59 AM #4
- Join Date
- Dec 2012
If you pay close attention to the 2 threads above you'll be able to do it yourself. I did exactly what is shown in the first set of pictures, I tapped the hole all the way through, (bad move) need I tell you the result. It looked real good, didn't work real good. I bought another manifold and had WFO do the surgery, I don't have a milling machine to mill the top of the boss. They did an excellent job!
01-10-2014, 08:04 AM #5
01-10-2014, 08:11 AM #6
01-10-2014, 04:45 PM #7
I have done several older pre 08 manifolds with a drill press and a clamp like the one pictured, the key is going in with a small pilot bit like 1/4" first,
you can buy older pre 08 exhaust manifolds on E-bay for $99.00 up to $200.00 they are cheap
I tried the new way to drill an older exhaust manifold based on the pictures of the one I cut in half,
I first went down with a 1/4" pilot hole all the way
Then went down with the 15mm drill bit all the way
Then I went with a 5/8" bit only about 3/4" of an inch,
Ran the 18mm tap only down 3/4" of an inch,
The oxy sensor fits perfect down past the threaded part and there is plenty of threads for the sensor to seat air tight,
and a thicker wall on the bottom means less chance to hit the water jacket
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