Caddy Engine (500), Recommended Hull Size-DD?

A general, non-powerplant specific, discussion on airboat technology, ie., hulls, rigging, polymer, etc..
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Rollbar1
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Mon Apr 25, 2016 3:31 pm

The guy said he has turned the motor over by hand to keep it freed up and has done that for years.

He also said we will pull the plugs and oil the rings and fire it up in the back of his truck and he will deliver it.

If so and everything works out, I will have a tranny and A/C unit and emission stuff for sale. I asked if the tranny is a TH-400, he didn't know but when we pull the motor out of the corner I'll be able to tell/read the #'s off it.

Thanks,
Jim

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Rollbar1
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Mon Apr 25, 2016 3:45 pm

Question, now that I know the motor is a 425CU, can I still go with a 14'x8', or do I need to go smaller like 12/13'x 7'6" etc.

Also, can I use 5052/.125 or ? for the hull?

Thanks.

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by One Eyed Gator » Mon Apr 25, 2016 4:01 pm

Be careful using a 425 as a DD motor they have a much lighter crank than a 472 or 500. Just a word of caution do some checking before you start spending a bunch of money on it.

SWAMPHUNTER45
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by SWAMPHUNTER45 » Mon Apr 25, 2016 4:12 pm

Poor choice of a DD engine, if it's not a 500 or 472 personally I would pass on it or go Chevrolet with a gear drive.

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Mon Apr 25, 2016 4:22 pm

Wow. That stinks, and since I'm a man of my word and told him I'll take it not knowing it was a 425 and not 500, I'll still follow through with the purchase and work from there. Guess I'll drop back and punt. My word means more to me around town that anything. Now to figure out how to use it.

Do you think if I went smaller on the hull it might take the load off the motor or that has nothing to do with it seeing a prop is pushing on the crank etc.

Thanks for the help guy's,
Jim

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Rollbar1
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Mon Apr 25, 2016 4:28 pm

Question, can I put a 472 or 500 crank in the 425 motor?
Is the block/internals the same as a 472/500?
If so how much do they run?

Thanks,
Jim

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Mon Apr 25, 2016 5:37 pm

Found this:

425CI.

In 1977 Cadillac introduced a new 425 cu in (6.96 L) V8, based on the architecture of the 472, but with a smaller, 4.082 in (103.7 mm) bore and the same 4.06 in (103 mm) stroke. The new engine was also 100 lb (45 kg) lighter.

The 425 was offered in L33 form, with a four-barrel carburetor, producing 180 hp (134 kW) at 4000 rpm and 320 lbf·ft (430 N·m) of torque at 2000 rpm, and L35 with electronic port fuel injection for 195 hp (145 kW) and 320 lbf·ft (430 N·m) of torque, but peaked at 2400 rpm.

SWAMPHUNTER45
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by SWAMPHUNTER45 » Mon Apr 25, 2016 8:47 pm

The 500 was made to push a heavy load, the 425 was Cadillac trying to pass emissions and get fuel mileage in a new lighter chassis. The 425 just lacks the torque of the 472 / 500 engines.

Yes the big crank can be used but unless your a master engine builder don't waste your time. The blueprint for a 425 with a 500 crank is the Cadillac Performance Engineering "460 Super Lite" build.

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Rollbar1
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Mon Apr 25, 2016 10:44 pm

SWAMPHUNTER45 wrote: The 425 just lacks the torque of the 472 / 500 engines.
Yes it does but from what I have looked at, it has decent torque.

I can always use it in a my small truck if that's what it comes to. :shock:

P.S. The guy called and as he said he wanted to run the motor. He said if it knocks or, he will return my money since he said he hasn't run it in a long time and has forgotten if there was a problem, he doubts it but at least he is honest. I did read about making a 425 into a 454 stroker motor but probably not worth it. http://www.hotrodders.com/forum/425-cad ... 32002.html

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Dr.Dan » Tue Apr 26, 2016 12:21 am

When you agreed to buy it for $300, didn't you think it was a 500? In my opinion the fact that it is a 425 is a real game-changer. It is an inferior engine.

I do not think it is worth $300 and I think it is a poor choice to start a build. If I was you I'd talk to the guy again and discuss how it wasn't what you thought it was.

Just my opinion.

dd

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Junker
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Junker » Tue Apr 26, 2016 6:05 am

Dr.Dan wrote:When you agreed to buy it for $300, didn't you think it was a 500? In my opinion the fact that it is a 425 is a real game-changer. It is an inferior engine.

I do not think it is worth $300 and I think it is a poor choice to start a build. If I was you I'd talk to the guy again and discuss how it wasn't what you thought it was.

Just my opinion.

dd
My thoughts as well.............

Just remember the ol' saying...." Failing to plan, is a plan to fail"

Before spending any more $$$ , sit back and use the search function and do some reading, educate yourself about your planned project.
This reminds me of a guy with "New truck fever" who go's to the dealership wanting a red, four door, 8 ft bed, diesel 4x4 and ends up with a blue, straight cab, gas burner, 4x2.....because that's all that was on the lot.
14 x 8 Hamant
383 - 2.38 Stinger
80" 3 Blade
Stainless rigged

SWAMPHUNTER45
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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by SWAMPHUNTER45 » Tue Apr 26, 2016 9:24 am

Best of luck with it, my advice is cut your losses.

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Tue Apr 26, 2016 9:42 am

Thanks guys.

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by Rollbar1 » Tue Apr 26, 2016 11:21 am

I met a car guy and I think he wants the motor/trans for what I have in it.

The search continues.

Thank you all for the help,
Jim

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Re: Caddy Engine (500), Recommended Hull Size-DD?

Post by MaxxForce » Tue Apr 26, 2016 11:28 am

I have a 500 caddy I'll sell, needs to be rebuilt PM me if your interested.
DONT RETREAT JUST RELOAD!!!

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