Thread: Need Advice!!

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I am running a stock 350 SBC with a 350/350hp cam,and tunnel ram,used strickly for street cruising.
What do you suggest for carbs. any help would be great!!

You are probably going to get advice not to use the tunnel ram on the street because they are really designed for high RPM usage, but I understand why you are wanting to do it. We all sometimes add parts for the "look" factor even though we realize they are not perfect. I ran two 500 CFM edelbrocks on the 302 in my '27, even though I knew a single would have been better, but I wanted two fours. I even ran straight, non-progressive linkage, and it ran fine.

If they still make the 390 CFM carbs, these would be closest to the ideal CFM's for a typical 350 Chevy, but you probably will end up with 500's, as they are more cost effective, I think. After I dial in the 350 in my T with the single carb, I am going to put two fours on it, simply because I think a hot rod needs multiple carbs to complete the look. That's just me.

BTW, tunnel rams are a little more peaky than a lowriser two four setup, but with a little playing you can get them to operate reasonably well. No question however that they will never be as smooth as one well matched carb.

Don

The Edelbrock 500 CFM carbs would also be a choice, though with a stock 350, nothing you put on it for carbs is going to work great. The smallest carbs you can get with vacuum secondaries are about your only alternative. The rpm operating range and all that CFM on the carbs, along with the open plenum and long runners will never be the ideal setup for a stock 350... If "the look" is that important to you, then you'll have to make some comprimises... A good dual plane intake with a 500 or 600 CFM carb would be the best setup for your engine.

I'm using a Edelbrock 600 cfm (#1406) on my 350/350hp engine but a 500 cfm would work just fine as well. Most of the local street cruisers use twin 500's on their 2x4 intakes, even on engines as large as the Mopar 440's.

This is what I am running now 600s, but think I am running to rich,leaned the carbs 4% per Edelbrock suggestion, and also went to a progressive linkage but I think it ran better with the one to one.

Thats flat out beatiful looking! 10 thumbs up on the engine.
Post more pics...

1200 CFM of carburation on a stock 350 is more then twice the cfm the engine needs.

A couple 390 Holley vac. secondary units would do the trick....

Thanks Denny that is exactly what I have right now, should I change the jeting to more lean than I have now? Thanks again

SST.....start out with a simple set up like Denny stated first. You might be surprised how the stock setup on the jetting helps the tunnel ram manifold. Then pull back a bit if you wish.

So your thinking I should stay with the 600s?

yeah, why not? It's all about learning curves. Have some fun.

I ran 2 Holley 600's on a 350 for years. I made sheet metal plates between two gaskets that blokced off the secondaries butterflies of both carbs, soldered the fuel transfer tube shut and ran progressive linkage. I did this so I could use both accelerator pumps on WOT .
The engine ran very crisp after I got it fine tuned and it got suprisingly good gas mileage on what was essentially a two barrel. I did have to monitor the rear cyllinder spark plugs so as not to go too lean because of the tnunnel ram airflow situation.

That is a sharp engine. Some of those parts don't look like off the counter items.
I am running 2 600's on my 392 Hemi, and I wish I had gone with 500's. I think I will try the blocking off the secondaries as suggested. I only wanted the 2-4's for 'looks' as someone else already said. I don't do burnout contest and I don't race it. I do dirve it often and lotta miles. I drive it on vacation often.

Jack

Would disabling the secondaries be a workable option? I know the orientation of the carb barrels sitting one-over-each-port would not exist, but it has a large plenum, which would help. Maybe a pair of 600s or bigger, since many carbs have smaller primary bores.

I know I have run a single 660 center squirter on a hipo 327 with success, but the manifold also had a large plenum.