Not trying to beat a dead horse, but the issue is not what compression ratio 413's originally had, but what kind of compression ratio you'll have if you use today's readily available, off-the-shelf pistons. And no, you can't assume that a replacement piston is just like the original or that it will give you the same CR. This is true of 413s and every other vintage motor. In fact virtually all stock replacement pistons for early high compression V-8's are the low compression variety and, especially if you use composition head gaskets, can easily drop the compression ratio a couple of points down from stock. Now the speed equipment industry offers a variety of pistons for older hi-po motors, and there are plenty of relatively inexpensive high compression pistons available for 440s, but NONE that I'm aware of for a 413. Just for one example, go to the Keith Black piston web site and look around. The only pistons they offer for a 413 will end up .080 below deck at TDC, and this will give you about 8:1 CR with open chamber heads and thick head gaskets. Closed chamber heads will be about half a point higher. I'm not aware of any other piston maker that has an off-the-shelf 413 piston with any more CR. Milling the heads and/or block will bring the CR up some, of course, but won't take care of the fact that you will have a non-quench motor (which limits how much CR you can safely run). Custom pistons can be made to order, but they cost $$$$ For these reasons, plus the extra 30 cubes, used 440s bring a lot more money than used 413s. That's just a fact. Doesn't mean you can't use a 413, or that they aren't good motors, just means they aren't worth a whole lot (unless it has all the right markings for use in a high-dollar collectible like a 300 letter car or max wedge). By the way, I picked up a "dead" 413 for $50 a few months ago. It was stuck, but I got the crank out OK (worth what I paid for the motor all by itself) and so far have three pistons out. Got sidetracked by other projects, but maybe will get the other five out someday. Curtis 59 Coronet 2 dr hardtop (413) 56 Belvedere club sedan (277) Plus 49 Wayfarer (flathead 230), 63 Valiant convertible (225), 64 Polara convertible (434 stroker), 65 Barracuda 4-speed (340), 67 Hemi Charger, 67 Barracuda coupe (360), 69 Cuda 383 fastback 4-speed, and 56 Studebaker Golden Hawk 3-speed OD (352) ----- Original Message ----- From: "Bill K." <pontiac@xxxxxxxxxxxxxx> To: <L-FORWARDLOOK@xxxxxxxxxxxxx> Sent: Wednesday, October 22, 2003 10:10 AM Subject: Re: [FWDLK] 413 Chrysler with 8 to 1 Compression Ratio????? > Cheap reference: > > Get about a '62 Motors Auto Repair manual, covers everything including all > the MoPar and will give you all the stats you need to compare with - HP, > compression, etc. > > > Bill K. > > > ----- Original Message ----- > From: "Ron Allyn Swartley" <Archangel1390@xxxxxxx> > To: <L-FORWARDLOOK@xxxxxxxxxxxxx> > Sent: Wednesday, October 22, 2003 9:55 AM > Subject: [FWDLK] 413 Chrysler with 8 to 1 Compression Ratio????? > > > > Hi Curtis, > Thanks for your reply. Whoever told you Chrysler 413 had 8 to 1 > compression ratio. It is a fact that all 413 that came in Imperials and New > Yorkers > had 10 to 1 and some 300 letter series and some Dodge and Plymouth Super > Stockers had 11 to 1 and even 13 to 1. Everybody knows that -----just ask > any guy who > has a 413. ----oooppps----sorry-----I see you do own a 59 Dodge with a 413. > I > raced both 413 and 440 and the big difference between the two was almost in > all cases some improvement other than the 27 inches. All the guys I raced > with > didn't pronounce a motor dead until they found out what was wrong with > it.-------Today some guys pronounce an engine dead just because THEY can't > start it. > > > Ron Allyn Swartley > > PS. I guess you do know the 59 Dodge did not have a 413 in it. The 383 with > 2/4s was a big as you could go-----------STOCK. > > -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > Over 25,000 pages of archived Forward Look information can be easily searched at > http://www.forwardlook.net/search.htm Powered by Google! -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- Over 25,000 pages of archived Forward Look information can be easily searched at http://www.forwardlook.net/search.htm Powered by Google!
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