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Are 425 Caddys any good?

Discussion in 'The Garage' started by MudFlap, May 4, 2004.

  1. MudFlap

    MudFlap 1/2 ton status

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    I am thinking about buying 2 caddys.

    One is a 79 Coupe Deville with a 425/400, but it needs motor and transmission work for $200

    The other is a 78 Coupe DeVille with a 425/400 and it is running for $300.

    I know that most people use 472s or 500s when they swap in a caddy motor, but how good are the 425s?

    Would it be a good idea to get the caddys or should I just wait to get a 472 or 500. It will either go in a K-5 or a toyota pickup.

    Thanks

    Trey
     
  2. MudFlap

    MudFlap 1/2 ton status

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    Come-on, I know that there are some Caddy experts out there.
     
  3. MudFlap

    MudFlap 1/2 ton status

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    Can someone please help me on this.
     
  4. 75-K5

    75-K5 3/4 ton status

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    Well, honestly I don't know anything about the 425 motors, but I don't think they're as worthwhile as a 475 or 500. You want the earlier motors if possible, such as the early 70's (pre-73 I think). That's about the extent of my lacking Caddy engine knowledge, ttt. /forums/images/graemlins/thumb.gif
     
  5. great scott

    great scott 1/2 ton status

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    I dont know of any one trying this, based on that alone I would look for the 500cid its bigger and badder with parts becoming more avlible all the time. the 425 on the other hand may be harder to find parts for, and did i metion the 500 is bigger /forums/images/graemlins/rotfl.gif. if your going to spend the time and money for a convertion go big!
     
  6. JDBlazer454

    JDBlazer454 1/2 ton status

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    Ok guess its time for me to pipe up and put in my 2 cents /forums/images/graemlins/grin.gif

    The 425 is just a baby 472 or 500, it utulizes the same block and exterior parts only thing that makes it different is the bore and stroke and head valve size. If you want the most out of a Caddy engine of course go with the 500 cid but the 425 puts out a good amount of torque for its cid. For more info check out www.500cid.com or www.cadcompany.com , the Cad Company site is the one that offers the best high perfomance parts for the Caddy's.

    I of course run a 472 and for how much I have into the conversion I couldn't build a big block chevy that gets this good of gas mileage with this amount of power and still stay this reliable /forums/images/graemlins/woot.gif

    Still put alot of thought into it before you dive into it, Caddy parts will run you equal to Chevy big block parts, conversion parts are hard to find and takes alot of measuring to get things to fit right and you will never be able to take it to a shop to get fixed if you ever get tired of tinkering on it...they wouldn't understand it. If you ever have any questions on the conversion feel free to PM me, I seem to be the resident Caddy person at the time /forums/images/graemlins/wink.gif
     
  7. nstarry

    nstarry 1/2 ton status

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    valve train bad not good look up cost to upgrade before install sorry eating they have a t-style rocker stud that is known to fail under any kind of RPM /forums/images/graemlins/frown.gif
     
  8. JDBlazer454

    JDBlazer454 1/2 ton status

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    Your right even Cad Company says that the OEM T-pedestal system is at best marginal for any kind of performance application. To upgrade with stock to small cam, Stage I Shaft Rocker Assembly 1.6:1 stamped rockers w/ pushrods--$349.

    I have never had any problems with my engine with the exception of a sloppy timing chain which broke in my first engine. I have never heard of any other problems other then that with the several Caddy engines I have been around.

    My opinion on whether to buy the 425 would be a no, try to find an older 472 or 500 pre '74 ('74 of course being the prime 472 year that has flat top pistons and 120cc heads /forums/images/graemlins/eek.gif ). Of course the older you go the less you will have to worry about finding a smog motor, '71 is the first year of the smog motor which is what mine is, all the smog has been removed from mine and an Edelbrock carb added and it gets up and scoots pretty well. Like a Chevy big block the power curve is towards the bottom where alot of trucks need it. But with you saying maybe putting it into a Toyota then the 425 would be plenty but I would buy both and sit on the extra one as a back up engine /forums/images/graemlins/grin.gif
     
  9. MudFlap

    MudFlap 1/2 ton status

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    I was thinking that I could buy both of them and put one of them in one of my trucks and then when I find a 500 and get the time and money to build it I can just swap it in right? If the 425s, 472s, and 500s all have the same external dimensions, it should be an easy motor swap and this way I will also have a lot of spare parts.

    What do yall think about this plan?
     

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