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Old 04-25-2019, 12:10 PM
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eschaider eschaider is offline
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Join Date: Feb 2006
Location: Gilroy, CA
Cobra Make, Engine: SPF 2291, Whipple Blown & Injected 4V ModMotor
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MKS 427 made an excellent point that I had forgotten to mention — size. The Coyote while about an inch narrower than my Modmotor is still huge. It is right on sizewise with a 427 SOHC engine which is impressively big.

My generation of SPF was among the first to be built to accept these huge engines. It is always challenging to keep from chipping the entry to the engine compartment when you install any of the usual engine picks. When you install a 427 SOHC, Coyote or a Modmotor (even worse) it takes three or four sets of hands to do it w/o incurring some damage to the car. Additionally things like the steering column need to be moved leftward on left hand drive cars to clear the engine and accessories.

Don't get me wrong I love the engine and its power but looking back in hindsight the primo pick (IMO) for these cars from a fun and ease of assembly standpoint is a big inch Windsor based engine. The primo pick if you want best resale, best authenticity etc. is the big block FE. The primo pick if you want easily achieved displacement and massive low speed torque is one of the big displacement 385 series engines.

Keep in mind the bigger the block and head casting the more weight you put on the nose of the car — unless you go aluminum block and heads which you could also do with a Windsor based engine and get a very nicely balanced car.

BTW a few thoughts in closing about Coyote's and supercharging. The standard Coyote bore size is 92.2 mm and the bores are on 100 mm centers. That leaves 7.8 mm of block webbing between bores. 7.8 mm is equal to 0.31 inches or just a whisker short of 5/16 of an inch and that includes the cast iron liner.

This sort of design will let you get by with a n/a engines but is tender, in the extreme, for supercharged engines. When you push out a head gasket on a blown motor, under power (where else do you do it?), it will torch the head and block. The appearance will be just as if you took an acetylene cutting torch to the metal. Neither the block or the head can be economically brought back to their as manufactured condition.

When you weld aluminum you produce a large soft spot in and around the area of the weld. This defines the weak spot where the head will next fail under power. You could, of course, remove the seats and guides from the head, anneal it and then re-heat treat it.

Once out of heat treat you can install new guides, new seats do a new valve job and you're good to go, sort of. Once you think you are all done don't forget you still have to re-align hone the cam bores in the heads — try to find a shop to do that! This is all a lot of work and money. It is cheaper to buy a new head.

Supercharged Coyotes will use up a lot of your money faster than you can imagin unless they make no power or you can't hook up the power. Once you hook up and load a supercharged version of that engine it is on borrowed time.


Ed


p.s. Something for anyone reading this post to be informed about is that you can not re-heat treat aluminum. Heat treatment is a one time event with aluminum. I misspoke when I suggested re-heat treatment of the casting. It is not possible.
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Last edited by eschaider; 06-03-2020 at 12:21 PM.. Reason: Added Postscript
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