Might be a dumb question but I don’t have a lot of old school engine knowledge.
i have a 355 sbc, running 9.5:1 scr, 64cc aluminum heads, a comp cam 12-242-2 with a Holley Strip Dominator and a Holley 750 brawler.
The rpm range on my camshaft is listed at 1,800-5,600 and the Intake is 4,500-7,600
Could this be causing any issues other than just poor performance on the low end? I’m looking into new intakes currently as this is what came with the motor when I got it.

 

I think you answered your own question. With that cam you definitely want to run a dual plane intake such as the Edelbrock Performer or something similar.

 

In addition too big carb probably double pumper?
Not sure of trans but could probably use better convertor if auto.

 

Look into a Edelbrock performer RPM air gap. And you will need a 2200-2500 stall converter to get you into your rpm range.

 

The standard performer rpm or even EPS is what I would look at.

 

That cam is the XE268 if memory serves.

The Strip Dominator is a hi-rise single-plane. Strictly for racing, really. Which is not a good match to that cam at all. That's a typical "all the fast cars have it" mistake.

Either the Performer or Perf RPM would be a much better match. Since those are dual-plane, the 750 is reasonable. In fact GM themselves used a 780 (the old 3310) on motors as small as the 327. Which intake would be best, would depend on what you're using the car for, what it weighs, and the gears & converter. In some cars, Firebird most especially, fitting the Perf RPM under the hood is a problem.

 

I ran a very similar cam in one the 350's I had put together. COMP's 268H.
The RPM Air Gap suggested was an excellent fit.
Any of the dual planes would do the job.
I also was carbureted on the smaller side. IIRC, a Holley 600 vacuum secondary was the first. Worked very well. Extremely drivable even as a daily.
A 670 was next and it was excellent as well.
Went through various converters too. Stock stall was fine. A little more stall was better. Still very well behaved on the street.
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The carb I got for free from my father. It is a double pumper. I’ve also been looking at getting a new 650.
the converter is a 2100 stall.

 

I just picked up a performer eps today after work, was still brand new in box, going to put it on this weekend.

 

Alright to anyone looking at this thread I picked up a Performer EPS today after work, I am running a 2100 stall converter and the carb is a Holley Brawler 750 double pumper. After the new intake goes on I found a shop that will dyno tune the carb to dial it all in.
Thanks for the info guys.

 

THIS I will be watching with interest!
If you start a new thread, please tag me. @skinny z

 

@skinny z this thread is basically dead now but quick update, I’ll start a new post with the big update.
car runs better with Performer EPS intake but rich. 0-60 time is a dog 6-7 seconds.
have an appt for a dyno tune the 25th of June.
we can run through the carb and dial in the timing, then I can start fine tuning the governor on the 700r4 to get shift points higher.

 

Good to hear that the dual plane has made an improvement in the seat of the pants feel.
I'd like to see how that carb is tuned to your combination.
Plenty of racers I know (real and virtual) run larger carbs than the standard "recipe" calls for. That said, mechanical secondary's aren't my thing. I get that some have excellent results when used in a street application but results to me also include fuel economy. Something about two sets of squirters adding fuel just seems to go against the grain.
What might be of more importance though is the physical size of the venturi and butterflies. A bigger carb will naturally produce less of signal to the booster. As such that throttle response might be lacking. Difficult to say with any certainty as I don't have the specs on the carb in play. It's probably a safe bet that it's overall larger in every dimension than say a 600 CFM unit. Your cam is done making power before 6000 RPM. Translate that into the carb requirements and you might see that less is more.
Anyway, I'll be following.

 

Personally I like the Q-Jet, up to 850 cfm of flow and only flows as much as needed. The small primaries give excellent off-idle performance and no other carb can touch the fuel mileage a properly setup Q-Jet can deliver.

 

There are more Quadrajet fans than most folks realize. The potential for fuel economy notwithstanding, you have to remember that if you're a Stock or Super Stock racer, that's what you've got. So the performance is obviously there too.
In my earliest racing days (waaay back) I had a Q-Jet and a Holley. I morphed into a Holley tuner of sorts as it seemed at the time it was the easiest to work on and had the most tech support available. This is late 70's/early 80's action. Fast forward and over the last twenty years of being back in the hobby it's been Holley in one form or another. Presently running a modified Barry Grant 750 VS and with even the slightest amount of luck, I'll be back to dialing it in yet again. Luck and money actually.