I'm definitely reading it the other way, but your way makes more sense Richard. Thanks for the clarification. (reminds me of a joke, next time we're together I'll tell it lol)
Thorley headers heat
- Thread starter Billygoat
- Start date
I'm definitely reading it the other way, but your way makes more sense Richard. Thanks for the clarification. (reminds me of a joke, next time we're together I'll tell it lol)
To get the alignment on the first shot, cut the head off a 3/8 bolt and thread that into the hole (driver's side?) where the intake has a notch cut into it instead of a hole for the bolt. That notch will get you lined up front to back and side to side, you just need to drop it into place parallel with the engine.
And yes, throw the rubber gaskets in the trash. My friend is a long time mechanic and racer, extremely knowledgeable on the BBO told me long ago those rubber gaskets for the front and back of the valley are junk. He recommended using a complete tube of Ultra Black RTV, half on the front and half on the rear. (This is for when installing block off plates in the FelPro style gaskets, one on left, one on right. Not for Turkey Tray style gasket)
Correct, thats what I thought was the setup with a muffler in the back, am I wrong in that understanding?
Just to clarify, if I'm correctly reading what the confusion might be, here's the factory setup. Each bank gets its own muffler, which is why we can get away with 2.5" mufflers. Then they Y together downstream, and there's one long, continuous run to the tailpipe.
If you were to have a muffler after the Y, you'd need to upsize it since it's flowing for all 8 cylinders rather than just 4, and there might not be enough room for one that tall unless you get fairly creative/custom.
Looking at the upper-right of this drawing, I see the exhaust pipe exiting to the side. Mine (and others I have seen) exit straight out the rear; perhaps with a curve, but still from the rear, not the side. Is side-exit the norm? I ask because I need to properly terminate the pipe; it's too close the the rear and is leaving soot. Plus it gets scraped when the exit angle is too steep.
Yes, a side exit is correct. As you know, anything below the bumper is going to get scraped.
My current one is swept downward and rearward a bit more than it should, but it's not completely below the bumper or rear facing. It's sort of in between. I'm hoping I don't scrape it too much, and might improve it someday. My Glenbrook had a nice routing, straight out the side with an interesting low-profile rectangular tip. Sounded good, and was out of the way. The tip was "interesting" for most folks, but appeared to be stainless and often spurred some commentary. I have no idea where it came from.
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I tried having mine exit out the side, I hated it, the noise bounced off everything on the right. Straight out the back is better. I do have a slash tip on it to blow the exhaust down.
Also if you're getting soot, it sounds rich.
as far as upsizing things, if you are redoing the exhaust 3" fits great and flows good enough for 99% of our ( my ) usage. def recommended
I have a single flow master 80(?), Like Larry above, in the back after the last crossmember, in that triangle. It just fits!
I dimple the block from end to end on the China Walls with a center punch just to give the sealant just a little better grip.
