Cross Ram intakes.

[EDC]

Barry Grant deal...

[falcongeorge]

MAN, has this place changed...

[rebelrouser]

Is it the cross ram design that is a problem, or is it that when those manifolds were designed the engine had less ci and then they are being put on today and just don't have the runner CSA area needed?
Dan Dvorak, told me several years ago that my 500 inch combination was way too much cubic inch for the factory mopar cross ram to feed. The other issue is that the runners are too long for most camshafts we use today as well. I think mine measured 14 or 15 inches in length.
I have a buddy that races NSS and he sent his converter back 6 times before it was right for his mopar cross ram, it was running the engine above the torque curve, they reduced the stall and it started to pick up. He is the only guy I know in NSS that has a stock cross ram that runs in the 9's
Stan

[miniv8]

MAN, has this place changed...

Why, because nobody has torn the head off somebody looking at crossrams for fun?

Not all engine building is hard core competitive

[falcongeorge]

MAN, has this place changed...

Why, because nobody has torn the head off somebody looking at crossrams for fun?

No.

[Kenova]

I have one of these, I rebuilt it probably 20yrs ago, welded up stripped and cracked bolt and pipe threads, but still haven't put it to use.


I want to build a new top for it and mount four 48mm IDF carbs and use it on the street for fun.

I've been trying to read upon the cfm ratings and from the little information I find, it contradicts everything I previously thought I knew about these carbs. CFM discussions seems to screw with everyone, as CFM rating for a carb on a single intake runner has to be huge because of all the reversion. That's how a hopped up tiny Aircooled V-dub can ingest a 600+cfm worth of carb.

I am wondering if putting them on a common plenum such as the Smokey, will give me satisfactory results. They are rated at 320cfm per carb and using four adds up to the CFM I'd like, but I wonder if they need the air pulsation from a single intake runner to work.

Yep! I have one too.
I have run across a few magazine articles on mods to improve fuel distribution but they were geared towards the use of the recommended Holley 850 carb. Perhaps the modern 4bbl. TBI systems may help improve the fuel distribution as all four throttle blades open at the same time.

I believe (my own supposition for what it's worth) that the SY1 was made for wide open throttle on engines in the 350 to 380 cu. in. range. I have been told (many times) that it wouldn't work on a street driven 400 sb. because I wouldn't be able to rev the 400 high enough. Just as Stan suggested in an earlier post, I believe the extra 30 to 50 cu. in. would lower the rpm. operating range enough that it could be used on the street. If combined with a set of modern heads I can see the manifold being a choke point, but you have to admit it would be one damn fine looking choke point.

Ken

[F-BIRD'88]

I just cannot see yhis manifold driving well working well on the street with any single 4 bbl carb..
Maybe with 4 rochester 2 bbls (sideways) on a custom top.
Or converted to Port EFi.

[tjs44]

I had actually planned to run the intake with a pair of spacers on a std block with like 428 CI and put EFI in the spacers and having the intake be dry with a pair of throttle bodies but gave up on that to run it on the short deck.No way to make it a dry EFI set up without the spacers.Tom

[swampbuggy]

The year was appx. 1973, it was 1/4 mile oval asphalt racing right down the road and they are still racing there today. In that year the 1964-5 Chevelle was popular. The Engine was a 400 block w/bearing spacers and a 3.00" stroke=321 C.I. with a STD. bore. The go to single plane was the Tarantula and then came the Scorpion ( i think ). Smokey ( i guess ) was the brains behind the Smokey Ram. The gentleman who ran the above mentioned engine combo tried the Smokey Ram and i don't believe the car slowed down any ( not sure though ) i will ask him the next time i see him, he is now about 85. Mark H.