My review on the cadillac 500

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duckhunter1984
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My review on the cadillac 500

Post by duckhunter1984 » Mon Mar 16, 2015 10:36 am

So I recently swapped my 350dd sbc for a 500dd cadillac.... This is going to cause a fight, but worst Decision I have ever made.... Everyone said how much more power....nope.... I mean it does have more power but not a lot by an means... This thing has been nothing but a money pit.... I would give anything to have my sbc and wood prop back and some one else had this big block and whirlwind prop... Not impressed... If you want more power get a reduction unit....

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nebraskaairboater
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Re: My review on the cadillac 500

Post by nebraskaairboater » Mon Mar 16, 2015 12:54 pm

When I made the swap it was night and day better. I could run a little dry with the caddy where I couldn't with the 350. What prop and RPM are you getting with the Caddy? Just curious. Reduction on any engine will always be better than DD for sure. My progression was small block chevy DD (trouble even getting on plane with 5 people on board), 500 Caddy DD (run a little dry with 3 people on board), then 2.12 to 1 Rotator on the Caddy (point and shoot for my area loaded). Would never go back to DD for sure.
I know it sucks when things don't meet your expectations.

Dan
Dan Porter, Jr.
Fremont, NE
16 x 8 1971 Flat Bottom Fiberglass Hull / 454 Chevy/ 2.38:1 OX Drive / 80" 3-Blade Sensenich S

duckhunter1984
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Re: My review on the cadillac 500

Post by duckhunter1984 » Mon Mar 16, 2015 1:22 pm

I am running a 72 inch whisper tip at 3000 RPMs..... And I mean it does have more power than my 350 but it is not substantial like I thought it would be going from a small block direct drive wood prop to this 500 Direct Dr. composite prop.... My small block seemed bullet proof as well this 500 seems very finicky and maybe I just don't have everything lined out yet

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Re: My review on the cadillac 500

Post by One Eyed Gator » Mon Mar 16, 2015 2:13 pm

With a DD all the small thing add up. Has it been rebuilt or pulled and put on a boat?

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Re: My review on the cadillac 500

Post by Striker543 » Mon Mar 16, 2015 6:49 pm

I feel your frustration. I made the switch fro the 350 dd to the caddy dd too and my caddy was finicky like yours. Once I figured it out though, I had a much better power source.

What can you tell us about the engine? There is a lot of room for tuning the caddys. Harmonic Balancer, HEI, and Carb is where I would be looking first. Buddy Branch recently tuned an Edelbrock Thunder series for me for a very reasonable price and it's been a great carb. Lots of guys also swear by a 1" carb spacer too.

Also might not be a bad idea to let everyone know what pitch your turning that prop at. Someone with more experience with Whirlwinds than me can probably tell you whether the pitch is about right for that engine before you start spending money on tuning.

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PAINKILLER
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Re: My review on the cadillac 500

Post by PAINKILLER » Mon Mar 16, 2015 7:02 pm

Is it a stock engine my dad had dd caddy that would run with 4 men dogs duck decoys no problem
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stan
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Re: My review on the cadillac 500

Post by stan » Mon Mar 16, 2015 7:59 pm

few years back i replace what was supposed to be a 500 with a 472 it was a night and day diferance turned out the 500 was actually a 368. not saying this be the case here just need to be checking all the little things to make sure everything is right

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John C
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Re: My review on the cadillac 500

Post by John C » Mon Mar 16, 2015 8:31 pm

to many variables here. If the caddy is truly a 500 Caddy, and it is running 100% putting out max power. the 350 cant touch it, both motors being stock. What PAINKILLER said is more accurate. Sounds to me like something is not right with this set up. Could be anything, to much to list. I have run 4 different 500 caddy motors, From pure stock to a 520 Buddy Branch motor that was a real stud. need more info on prop pitch, what carb, timing, was the motor rebuilt or right out of the car, how many miles if not rebuilt, who rebuilt it if it was rebuilt, ECT,ECT,ECT. I agree that a reduction unit is the way to go. But I also think if that Caddy is a 500 and its running right you would not have the complaint that you do. JMO.

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Re: My review on the cadillac 500

Post by Bdriller » Mon Mar 16, 2015 8:52 pm

did I overlook what size boat? if you have that prop pitched in sweet spot on the correct size hull with good rigging and you turn it 3k it will be sufficient to make most folks grin, doesn't matter what your spinning it with ,providing its not to heavy and a caddy 500 is not to heavy for a good wide 14' I suspect that you have quiet abit to learn yet, which is not shameful.

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pontoon outlaw
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Re: My review on the cadillac 500

Post by pontoon outlaw » Mon Mar 16, 2015 9:27 pm

:slap: proud owner of a Cad 507 that smokes them all running the Hill :lol: Buddy Branch built tough :cheers:

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Re: My review on the cadillac 500

Post by Bdriller » Mon Mar 16, 2015 11:51 pm

pontoon outlaw wrote::slap: proud owner of a Cad 507 that smokes them all running the Hill :lol: Buddy Branch built tough :cheers:
Hes the man that buddy branch, anybody can build a motor but when he dose it, it has heart and soul!

SWAMPHUNTER45
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Re: My review on the cadillac 500

Post by SWAMPHUNTER45 » Tue Mar 17, 2015 7:32 am

All I can say is you did something wrong or ended up with a 425 instead of a 500.

A bone yard 500 makes a 350 look weak much less if you know what your doing like some of the people on here. I run a Branch 514 and know several guys who use his engines or have gotten his assistance and none are weak. My big coastal boat is a beast.

rotator75
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Re: My review on the cadillac 500

Post by rotator75 » Tue Mar 17, 2015 10:42 am

Dam that sucks a little more work with a rigging change and BBC with a gear would of been the way to go then you would of had something reliable.Caddys make good boat anchors to much bottom end trouble unless built right with lots of dollars to keep parts from leaving the pan :violent1: Its sucks when a man puts time and money into something and doesn't turn out.Good luck with the boat.

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John C
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Re: My review on the cadillac 500

Post by John C » Tue Mar 17, 2015 1:40 pm

A stock Caddy in a DD application is a reliable motor. As long as you know what you are starting out with. Any motor can give you problems if it has problems when you bolt it on your boat.

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Deano
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Re: My review on the cadillac 500

Post by Deano » Tue Mar 17, 2015 9:18 pm

At this point, addressing the radical difference that should have
resulted from your engine swap would be beating a dead horse.

There are those of us here that are capable and willing to help you identify and correct whatever it is that is causing your lack of power. Never mind the preachers of doom, they aren't where your help will come from anyway.

As JohnC already pointed out, there are to many variables for anyone to help without more information.

OneEyedGator asked if it was rebuilt or just installed out of a car. You haven't responded. I thought I remembered that you just put a gasket set in it and installed it. If so, no shame in that, you're not the first one, I have done that myself. Did it have a points dist. or did you upgrade it to HEI dist.? Did you install a new timing chain? You had mentioned changing the heads, did you do that? If so, what pistons are in it?

Plenty of knowledgeable people here to help; just need enough information to be able to.
"The suppression of uncomfortable ideas may be common in religion and politics,
but it is not the path to knowledge; it has no place in the endeavor of science."
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sidejobs
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Re: My review on the cadillac 500

Post by sidejobs » Tue Mar 17, 2015 9:30 pm

Sbc , wood prop ..... Caddy with a composite .... If you're not grinning ear to ear there is a major issue
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crowhater
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Re: My review on the cadillac 500

Post by crowhater » Tue Mar 24, 2015 10:12 pm

My advise is stop what you are doing and ask questions. There is no chance a SBC can outperform or even get close to a 500 Caddy on a DD platform. This is not even debatable, so now let's move to the real problem. Their are all kinds of Caddy guys that can help you get your engine running right. On my first Caddy it took me a little time to get it dialed in. At the time I did not know about this site so I was pretty frustrated. Once I got my engine dialed in it was a night and day difference.

Tell us about your engine. Are you running a factory camshaft, what kind of carb, what kind of exhaust? Do you have the heavy cast iron balancer on the front, do you have an HEI distributer? All the little things can add up to hurt performance. I have seen people switch to HEI Distributer and still run old school spark plugs. If your timing is incorrect it can have a major effect.

Also the overlooked things can bite you. One of the biggest is throttle cable pull! I can't tell you how many people have over looked throttle cable pull. Just because you push your gas pedal all the way down does not mean your carb is open 100%. You need to have someone hold it down and check at the carb to see if your carb has any more throttle avalible.

Do you know what you total timing is, at wide open throttle?

Do you know that your carb is getting at least 6psi at wide open throttle and maintaining that pressure?

Are your spark plugs and plug wires good?

Does your engine have good compression?

Are you running regular unleaded fuel or super?

My 500 caddy was all factory except for a Cloytes timing chain and .60 over bore. ( 10.1 ) compression. I spun a 72x44 Florida airboats wide blade paddle prop to 3000rpm. It did to do this at first, I had to Tweak a few things to make it happen.
18x8 Alum, 496 BBC, 2.6 CH4, 4B 82" S-blades

SWAMPHUNTER45
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Re: My review on the cadillac 500

Post by SWAMPHUNTER45 » Wed Mar 25, 2015 7:58 am

All good questions to help get to the answers !

Are you running a vacume advance or is it disabled?

That CAM question is a big ? High duration is bad on DD

Pics help too.

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BigDaddyT
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Re: My review on the cadillac 500

Post by BigDaddyT » Wed Sep 02, 2015 8:18 pm

Deano wrote: There are those of us here that are capable and willing to help you identify and correct whatever it is that is causing your lack of power. Never mind the preachers of doom, they aren't where your help will come from anyway.
PM'd you.
13' 6" Combee Hull with 472 Caddy. Whirlwind Whispertip 72" Prop

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