Here is my 408C

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Aug 14, 2014
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Madison, WI
My Car
1971 M-Code Mach 1 w/408C stroker
Had a 392 Windsor stroker built several years ago with a Scat crank by a knowledgeable race-type shop. They put in a 1 piece rear seal.  Got it installed an running and sure enough had a rear main seal leak. Took it back and builder disassembled everything and double checked it. Said there were no problems that he could find. He agreed to put it on the dyno to make sure before I took it back and sure enough, after a few runs, small drops of oil on the floor. Could find no issues with machining or assembly. I just happened to be checking out another nationally recognized custom engine builder that specialized in Ford FE engines and noticed that in his quote he would not guarantee no rear main leaks using Scat cranks. Don't have any reason why. Someone here mentioned the drilling on the flange, but I have no Idea. Motor was strong and reliable but I had to just learn to live with a little oil leak. Not a Cleveland, but maybe similar experience to others with stroker engines and Scat cranks in a Ford.
Wonder if it's more common with the old cranks? I'm also curious about what another member was saying about it coming through the flywheel bolt holes?
The bolt holes go all the way through so the oil in the pan gets slung onto the holes and since the thread to thread seal is not perfect, oil makes its way to the front side of the flywheel/flexplate and down. If it makes it alll the way to the backside of the flywheel it will ruin the clutch. It usually put 1-2 drops on the ground every time you park it after driving it. Some say just use a boat load of lock-tite and it won't leak. It didn't work for me on the 408C. I still need to pull the transmission to seal it up. What did work on the Boss 347 build was a thin coat of Grey Stuff on the crank to flywheel mating surface, lock-tite on the flywheel bolt threads, and Grey Stuff under the heads of the flywheel bolts. The threads need to be clean and dry. Who knows, perhaps your luck is better than mine. P.S. The B347 crank was a Molnar, also through drilled. Chuck
Ingeresting. I dont remember my Molnar having the holes through. Does anyone have a pictures of these through holes? There would be very deep.
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Dec 11, 2015
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My Car
73 Mach 1
Chris, your build is essentially pretty similar to mine. I have the Robbmcperformance pump on stock lines to my Quick fuel 750 and it runs great. You don't want to over carb a street machine. You have blue thunder intake, I have Air Gap. I do have the Trick Flow heads and I have slightly more cam lift/duration but just slightly. If you told me your builder wanted a practice cleveland block for the rms, I would have let you take the spare I have in my shop.  Use the 195° stat and the plate you got from TMeyer, they're important.

Here's the set-up my Quick Fuel carb is set to...these settings should be a great place to start with yours...mine was dyno tuned...

You should be lookin at about 400±hp to the rear wheels!!!  Last spring I put some Mickey Thompson ET Street 295/55r15's at the rear because BFG radials were a joke. I can still light 'em up when I want to but they have much more stick.
Hey Eric, sorry I missed your call dude. 430AM comes quick for me during the week and I shut down early. Thanks for the offer with the block but whats done is done. Hopefully with everything else my builder did that seems correct applies to the RMS also.

Nice to know that I should be around 400RWHP being that that was my goal. Should make for a nice street cruiser. I'm looking into DR's but need to decide on a wheel size first. With regards to the carb settings...I'll have to find out the difference between the carb you have and the quickfuel slayer that I have. I know both are 750CFM but I'm sure there are some differences. Seems like a good starting point though. Thanks
Here's a link to the Quick Fuel carb I have, if it helps for your comparison...
Slayer is on the left. Big difference is my vacuum secondary.

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