CRG Discussion Forum
Model Specific Discussions => Trans-Am Camaros => Topic started by: bcmiller on December 21, 2021, 11:27:22 PM
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I am wondering if anyone has run a single Holley 4 barrel on a Cross Ram intake before.
I bought a 1981 dated Offenhauser Cross Ram intake and two 660 cfm carbs, but that was not going to be anywhere close to street friendly on the built 355 it was going on. So I sold the carbs and am now thinking about replacing it with a new top. See pics. The intake I have did have some minor grinding done on it to clearance the accelerator pump on the front of the passenger side carb area. This is generally not seen with a carb installed.
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Actually, I have...not on a Chevrolet. Considered the 'best' Cross-Ram for a small block Ford was the Shelby 289-302 version. It came with a single or dual carb'ed top plate. With the single Holley, it was a real screamer, and street friendly. I'm sure the Chevy version can be (or is just as good) for what you're intending to do. That said, hopefully more qualified Chevy Cross-Ram guys can chime in.
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Well if it will work on a 289 or 302 Ford I think the same concept would hold for a built 350. Thanks!
Anyone else have experience in this area?
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No experience with the single four top on the Offy crossram but we are looking forward to you being our guinea pig!
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Very good write up on Smokey Yunick's single 4-barrel crossram
https://nastyz28.com/threads/smokey-ram-sy1-combo-and-how-it-works.294997/
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If you decide to change intakes to a single 4 barrel intake. I would be interested in the intake you have.
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Very good write up on Smokey Yunick's single 4-barrel crossram
https://nastyz28.com/threads/smokey-ram-sy1-combo-and-how-it-works.294997/
I agree with the author's conclusion on removing the 'dams' inside of the intake. I also did this on my Cross-Rams (Ford), and it does help removing the puddling of gas. Remember, folks this type of intake is very much a different animal. The large plenum, long runner design has its short comings, and also has its pluses. As mentioned, a strong pump shot is required for the elimination of a lean stumble off idle. A little more 'tuning' is required on this combo. Also, FWIW, the Edelbrock Smokey Ram appears to have a shorter carb/intake height (less plenum volume) than what I have run (again, on the Ford versions). This, in theory the Chevy should be the 'better' of the two. Just an opinion, no data on a back to back test.
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The Smokey Ram while being similar to a cross ram, does take somewhat different parameters to tune properly. I wouldn't feel comfortable taking settings off one to use on the other.
I do have the Smokey Ram on my 68 Z/28 A/S with the 830 Holley and it is tuned quite well. Of note, the history of this car goes back to many consultations with Smokey himself to get the tune right.
This installation is on a relatively stock factory 302.