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Intake Manifolds Edelbrock Stock or Mondello others [message #285693] Mon, 24 August 2015 01:26 Go to next message
jturbo is currently offline  jturbo   United States
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Can we start a poll here

Edelbrock (Performer) is this worth the inconvenience and price?

Mondello Same Questions (Also I have read that this and the other intake have fitment issues.

Stocking GM Intake (Is this the best option?

Cross over to block or not block ??

what is best way to block the crossover?

1. Gaskets?
2. Iron Blocks?
3. Metal plates?
4. Fill it ???



1978 Royal 403 1977 Birchaven 455 1977 Kingsley 455 All under Upgrading and restoration Rosemead California
Re: Intake Manifolds Edelbrock Stock or Mondello others [message #285710 is a reply to message #285693] Mon, 24 August 2015 04:58 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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jturbo wrote on Mon, 24 August 2015 02:26
Can we start a poll here

Edelbrock (Performer) is this worth the inconvenience and price?
No

Mondello Same Questions (Also I have read that this and the other intake have fitment issues.
There is not a Mondello intake.. Rockwell intake? No

Stocking GM Intake (Is this the best option?
Yes. Or Toronado intake

Cross over to block or not block ??
Block

what is best way to block the crossover?
1) fill the head, 2) fill the intake, 3) use block off plates.

1. Gaskets?
2. Iron Blocks?
3. Metal plates?
4. Fill it ???




C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Intake Manifolds Edelbrock Stock or Mondello others [message #285712 is a reply to message #285710] Mon, 24 August 2015 06:36 Go to previous messageGo to next message
Ronald Pottol is currently offline  Ronald Pottol   United States
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Location: Redwood City, California
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Senior Member
A note about intake vs exhaust mods. Intake mods only increase power,
exhaust mods often increase efficiency in in most other circumstances as
well as boosting power.

On Mon, Aug 24, 2015 at 2:58 AM, Charles Boyd
wrote:

> jturbo wrote on Mon, 24 August 2015 02:26
>> Can we start a poll here
>>
>> Edelbrock (Performer) is this worth the inconvenience and price?
>> No
>>
>> Mondello Same Questions (Also I have read that this and the other intake
> have fitment issues.
>> There is not a Mondello intake.. Rockwell intake? No
>>
>> Stocking GM Intake (Is this the best option?
>> Yes. Or Toronado intake
>>
>> Cross over to block or not block ??
>> Block
>>
>> what is best way to block the crossover?
>> 1) fill the head, 2) fill the intake, 3) use block off plates.
>>
>> 1. Gaskets?
>> 2. Iron Blocks?
>> 3. Metal plates?
>> 4. Fill it ???
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
>
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> GMCnet mailing list
> Unsubscribe or Change List Options:
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1973 26' GM outfitted
Re: Intake Manifolds Edelbrock Stock or Mondello others [message #285713 is a reply to message #285693] Mon, 24 August 2015 06:51 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Location: Harvest, Al
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Senior Member
There is another option for the 403's. In later years GM introduced an aluminum intake for the small block Olds 350. This is the same block as our 403s. I have one on my coach. I did have to drill and tap a couple holes for various sensors, plug the EGR ports below the carb, and make caps and gaskets for the EGR and choke.

It is a bit taller than the stock manifold and the air cleaner is pretty tight against the unraised hatch. I'm probably going to cut the thickness of the hatch down to compensate. Weights a LOT less. Easy to install by myself.

I used the stainless block off plates.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: Intake Manifolds Edelbrock Stock or Mondello others [message #285726 is a reply to message #285693] Mon, 24 August 2015 09:44 Go to previous messageGo to next message
Chris Tyler is currently offline  Chris Tyler   United States
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A while back I scored a performer at a swap meet. Talked to edelbrock tech guy about it. He said they had no dyno data below 2500 RPM but that there would be 12-15 ft/# dif in torque at 3000-3500 range at full throttle
It would make more at higher RPM but we rarely do there
Oddly enough he said the older edelbrock 2 plane design [C3B?] might be better for our application if you can find one.
Decided it wasnt worth going through with the swap and building a raised engine hatch for the marginal difference unless I needed to pull it anyway


76 Glenbrook
Re: Intake Manifolds Edelbrock Stock or Mondello others [message #285766 is a reply to message #285693] Mon, 24 August 2015 16:55 Go to previous messageGo to next message
GeorgeRud is currently offline  GeorgeRud   United States
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What about the Rockwell aluminum intake manifold patterned from the Toronado intake?

George Rudawsky
Chicago, IL
75 Palm Beach
Re: Intake Manifolds Edelbrock Stock or Mondello others [message #285771 is a reply to message #285766] Mon, 24 August 2015 18:21 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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GeorgeRud wrote on Mon, 24 August 2015 14:55
What about the Rockwell aluminum intake manifold patterned from the Toronado intake?


Lynn at Mondello told me Gary Rockwell died and theyy now own the Rockwell manifold and rights?? He said they were a little more then $500 from Mondello? Don't known if it is true or not?


Roy Keen Minden,NV 76 X Glenbrook

[Updated on: Mon, 24 August 2015 18:22]

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Re: Intake Manifolds Edelbrock Stock or Mondello others [message #285798 is a reply to message #285766] Mon, 24 August 2015 23:56 Go to previous message
George Beckman is currently offline  George Beckman   United States
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GeorgeRud wrote on Mon, 24 August 2015 14:55
What about the Rockwell aluminum intake manifold patterned from the Toronado intake?


I have a Rockwell. They are very light which is nice as Kerry mentioned. Grab one of the stock manifolds on the engine and you think it is still bolted down.

I had some trouble getting Rockwell to seal all ports. The first effort sucked 4 quarts of oil in 280 miles. I suggest setting it in place with plastigauge taped on top and bottom of each port. I got 0.002 on all ports the last try. Put two cut-off studs on one side with a notch for a screwdriver cut into the tops. Then when all is ready place it over the two bolts as hinges and swing it down like closing a door.

The Rockwell has no crossover so the blockoff problem is solved, but because I used Patterson gaskets the plate is still there so there is no cavity.

As for extra power? I would not count on it. I have headers and Rockwell intake. I would say at 2500-3000 I notice zero difference. The Rockwell is nice in that it still fits under the deck. I love the fact that the GMC doesn't have a "dog house" between the seats.

Efficiency? Gene Fisher says GMCs get between 8-10 mpg depending of whether you tow or not. After a new engine, manifolds, EFI, I would say a GMC gets between 8-10 mpg depending on whether or not you tow. I did get 10.7 on a 3000 mile trip with a 2.73 (yes that is right) final drive. Very hard on engines and transmissions. Plan on going up some hills in low gear. Probably some hills I would not have been able to climb. You can go 55+ in second gear without hitting 3K RPMs and often you need to. On the other hand, I still have it for when I get a Manny Diesel.

Motorhomes are heavy and push a lot of air. They say in the 70s the GMC was the next slickest vehicle in the GM line other than the Corvette. It still has to push a lot of air out of the way. I am just saying.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
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