Cadillac Edelbrock Intake Modification

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crowhater
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Cadillac Edelbrock Intake Modification

Post by crowhater » Mon Jul 13, 2015 12:09 pm

I have done a couple of these but I never remember to take any pictures. This weekend a friend asked me to modify His 500 Cadillac intake manifold and this is what the mod looks like. What I did was weld the plenum divided all the way to the top and I welded the exhaust cross over shut so hot exhaust gas can't flow under the carb. I know the intake looked rough but after grinding and a quick sandblast it looks factory. Add a 1" divided spacer on top of the divided intake and you will pick up power on a direct drive Cadillac. If you wanted to get crazy you could actually cut the exhaust cross over off the bottom of the intake after you have welded the ends shut for a slight weight saving.


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Re: Cadillac Edelbrock Intake Modification

Post by One Eyed Gator » Mon Jul 13, 2015 12:15 pm

Did the same thing to mine with your advice some time ago.

I ended up cutting a thin piece of stainless sheet metal at set it over the exhaust crossover opening it the head. Without the piece of metal it would burn through my gaskets and start leaking. The exhaust leak sound just drove me nuts.

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crowhater
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Re: Cadillac Edelbrock Intake Modification

Post by crowhater » Mon Jul 13, 2015 12:51 pm

One Eyed Gator wrote:Did the same thing to mine with your advice some time ago.

I ended up cutting a thin piece of stainless sheet metal at set it over the exhaust crossover opening it the head. Without the piece of metal it would burn through my gaskets and start leaking. The exhaust leak sound just drove me nuts.

And did you see the difference? Everyone spends buckets of $$$$$ looking for more power and here is a DIY that gets you more power. All the little things can really add up if a person just takes the time.

If I was doing this job for my own Cadillac Direct drive I would also port match the intake manifold and the cylinder heads to the gasket.
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Re: Cadillac Edelbrock Intake Modification

Post by One Eyed Gator » Mon Jul 13, 2015 4:17 pm

Yes, got about 75 more rpm, got to add a little pitch. And yes every little bit help.

Now I am looking to get everything I cam out of my little 5.3 ls. Never stop always the quest for a little bit more.

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Deano
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Re: Cadillac Edelbrock Intake Modification

Post by Deano » Mon Jul 13, 2015 5:37 pm

This is about the best "post divider rebuild" picture that I've seen of a 2115; Courtesy of Sidejobs.

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SWAMPHUNTER45
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Re: Cadillac Edelbrock Intake Modification

Post by SWAMPHUNTER45 » Tue Jul 14, 2015 10:41 am

The real direct drive test is will the Edelbrock modified divider give any gain in engine power over a stock intake or is this just a weight savings.

I have one done up now just trying to find the time to swap out and see.

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Re: Cadillac Edelbrock Intake Modification

Post by crowhater » Tue Jul 14, 2015 12:12 pm

SWAMPHUNTER45 wrote:The real direct drive test is will the Edelbrock modified divider give any gain in engine power over a stock intake or is this just a weight savings.

I have one done up now just trying to find the time to swap out and see.

The factory intake with a 1" divided spacer will out perform the Edelbrock in its stock form but your gains are diminished because of the weight of the intake. The Edelbrock intake modified with a 1" divided spacer performs better that the factory intake. It is equal in the low RPM range and performs better in the upper, then factor in the significant weight saving.



For you reduction guys this modification does make the intake perform better but the biggest gain is in the spacer because you need more plenum volume. I have run the 500 Cadillac with a 1.7, 2.5, and 2.6 reduction. I have used 3 blade and 4 blade Falcon, as well as 3 and 4 blade S.

I have used factory intake, Edelbrock intake and the Bulldog intake. The Edelbrock does a good job into the low to mid 4000rpm range, after that the Bulldog takes over. Understand that a Cadillac that can run 52-5400rpm is an expensive undertaking and will expose every weak part in your engine
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Re: Cadillac Edelbrock Intake Modification

Post by sidejobs » Tue Jul 14, 2015 2:15 pm

SWAMPHUNTER45 wrote:The real direct drive test is will the Edelbrock modified divider give any gain in engine power over a stock intake or is this just a weight savings.

I have one done up now just trying to find the time to swap out and see.
With the correct cam , the 2115 welded up with a 1"divided spacer is a HUGE improvement
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Re: Cadillac Edelbrock Intake Modification

Post by SWAMPHUNTER45 » Wed Jul 15, 2015 7:27 pm

Sides that is a outstanding fabrication job, mine looks nowhere nearly as nice!

I agree with Deano, finest I have seen!

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