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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
Forget all that work, just replace the transmission top cover with the newest configuration cover, route the breather hose overboard.
Block the breathers using solid bolts.
About 90 bucks for the cover.
Vs the cost of a rocker box gasket set (About 100 bucks) and S&S breathers 300 bucks.... 300 bucks for breathers????
And about 4 hours+ work vs 30 minutes, and a lot of money.
I have 2 M8 machines that I have set up with the new transmission cover vented overboard, head breathers blocked off with solid bolts, I have not seen a drop of oil on the end of the breather hose.
^^^^ ^^^^
Ref:8
29400448
VALVE,ENGN BRTHR,COVER ASSY | top, with 34800071 and 34800043 (black)
I'm cheap. I took the trans cover off, used a step drill to punch a hole in the right spot, & a matching hole in the gasket; inserted a Dorman PCV Valve Grommet ($8 on Amazon) and a Toyota PCV Valve ($20 on Amazon), and a short piece of hose to route the fumes overboard.
Originally Posted by Dan89FLSTC
Forget all that work, just replace the transmission top cover with the newest configuration cover, route the breather hose overboard.
Block the breathers using solid bolts.
About 90 bucks for the cover.
Vs the cost of a rocker box gasket set (About 100 bucks) and S&S breathers 300 bucks.... 300 bucks for breathers????
And about 4 hours+ work vs 30 minutes, and a lot of money.
I have 2 M8 machines that I have set up with the new transmission cover vented overboard, head breathers blocked off with solid bolts, I have not seen a drop of oil on the end of the breather hose.
On big breathing TC engines, I like the TMan or MegaFlo vents (Tman drills and taps a passage in the heads, Jim @ MegaFlo drills/taps a port in the rocker boxes. Either way helps.
On big breathing TC engines, I like the TMan or MegaFlo vents (Tman drills and taps a passage in the heads, Jim @ MegaFlo drills/taps a port in the rocker boxes. Either way helps.
I will look into that.. thank you..
if you have contact info for them (mega flo) i would appreciate it..
Edited: I found their website.. thank you..
Last edited by 98hotrodfatboy; Jan 5, 2026 at 06:20 PM.
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