FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: babybolt on June 05, 2017, 08:08:08 AM
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MY apologies if this has been posted before, Car Craft May 1969:
http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990392503331/1969-05_CC_SOHC_Magical_Mystery_Tour_1-10.pdf
Showed up on YellowBullet.
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Doug, thanks for posting that. Great article! I just about jumped out of my chair when it came to the part about cam timing. Back in 2007 (I think...) I ran my first SOHC on the dyno with magnetic sensors on the cams, to try to figure out what they did as engine speed increased. To my great surprise, the right cam retarded, but the left cam advanced. I couldn't hardly believe it, but the data was the data, so I went with it. I have never seen any validation of my test in any other form, but there it was in the article you posted!
Since going to EFI I have always had sensors on both cams, and with my more recent engines I have found that the left cam also retards, not advancing like it did in my original test. So I have concluded that the cam timing variation will change depending on the cam and valve spring setup. Just speculating, but maybe with lighter valve springs (like I had on my original test engine), the left cam will tend to advance, while with heavier valve springs it will tend to retard. And the right cam will always want to retard.
I also thought that the chain tensioning information in the article was interesting. They use 10 ft-lbs on the adjusting bolt. I've read about using 105 inch pounds, which is about 9 ft-lbs, and I personally like to use 65 inch pounds, which is about 5 foot pounds. Maybe I should be looking at using more chain tension...
Also, the bolt-on support plate that was used in the bottom of the block was interesting. The blocks of course were known to explode in fuel applications, and apparently the plates helped them live. I have never seen an article supporting this kind of plate, or girdle, on the block before from a well regarded engine builder. Makes me think that the FE girdles that are available might be a really good idea on a non-crossbolted block...
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I have a copy of that cover page hanging in my trailer. Bought it with a handful of interesting FE pictures at a swap meet that were in plastic covers. Neat to see what the rest of it was.
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Thanks Doug! And here I thought when i clicked on it the article was one I had already seen....NOT! Amazing that I missed it the first time around. I has also thought Jay had seen this long before as well. Great article with lots of details!
Jay, on the old Forum a fella needs the weight of an all-aluminum cammer.....this you would know.
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Yep, 540 pounds, no headers, flywheel, or alternator:
(http://fepower.net/Photos/Posts/SOHCwght.JPG)
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Jay, do you wind up using as much as the 8* for the left and right cams Ed set his motors up with in the above article ?
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At one of our SCTA meetings (land speed racing) the "Old Master" was the featured speaker. He was quite eloquent and very gracious to take questions about all of his racing engine exploits from land speed racing to Indy cars.
Eventually, some one asked him about the Super Snake and other Top Fuel Ford SOHC engines he had built. This from Pink hisself. "Making power was never a problem...BUT...the blocks were junk and you couldn't remove the heads in a timely fashion for between rounds maintenance".
One small side note touched on in this article. Pink, as well as Pete Robinson preferred the non-adjustable rocker arm with different thickness lash caps to the adjustable rocker for nitro racing.
Fun article indeed!
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What intake is that on the black block above the Cammers carb?
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It is amazing that this article only recently surfaced since the 427 SOHC has been regained popularly with reproduction parts available for almost 10 years.
Have to keep in mind that the article is about building a 80% nitro engine with huge bearing clearances.
Just makes you wonder what secrets Pink didn't divulge...
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That bearing clearance is close to being measured in "football fields" instead of "thou".
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What intake is that on the black block above the Cammers carb?
That is a Dove single 4 high riser intake, plus Dove high riser heads. Sold that setup quite a while back...