bcg88

I am running a stock 350 in a 69 Delta Convertible. I am working on a plan to modestly upgrade the motor. I am currently thinking of adding an Edelbrock intake, 4BBL Holley (it has a 2BBL today) and HEI.

What are your thoughts on these improvements? Best guess for HP add?
Does it make sense to upgrade the intake and carb but leave the cam stock?

2blu442

I like the dual plane Performer intake for a street driven car. What kind of carb are you planning to use? I've used Edlebrock and Holly carbs, but find myself coming back to the Quadrajet. Do you have single or dual exhaust? That's another area you can upgrade without major engine work, and helping the engine breath better should help both performance and economy (when your not using the secondaries!). I don't know what the actual hp increase would be, but I believe you'll feel a difference in power with just these changes and leaving the cam stock. My 2 cents worth! John

bcg88

It is strictly a street cruiser. I put dual exhaust on it a few years ago. I have a slight leak in the intake manifold and I figured if I need to pull it to fix it then why not upgrade it. I was thinking the Edelbrock Performer and a Holley Street Avenger 4BBL 570 CFM.

2blu442

I have that intake and carb on a 1972 Cutlass. Nice acceleration once you get rolling, but I've got a hesitation off the line that I've not resolved yet. If I had it to do over again I would have stayed with a quadrajet. John

Edveen

Hey bud,

In my opinion, I think you should go for a quadrajet since it is the best carburetor for street use. Holley carbs excel in race applications, but the quadrajet takes the cake when it comes to street use. Its more forgiving when tuning and has much better throttle response in my opinion. You will definately feel a difference when those secondaries kick in too.

Also, ive read that the Ebrock performer intake is no better than the stock intake. I think a good upgrade would be a Performer RPM Intake. If you do get a qjet, make sure you get one that was made for your engine. That number would be 7029250.

Ed

Edveen

Many people say the best HEI is one from a GM car. But I have had good luck with the Pertronix Drop in HEI unit. No problems. Many also get a conversion kit where you keep your points distributor, but replace the points with an electronic one(http://store.summitracing.com/partde...5&autoview=sku
I would think the best performing would be an HEI from an Oldsmobile that you recurve yourself.

Ed

Jim's rare 80

Hi. I have a 73 Olds 350 (bored 0.30) in my 80 Cutlass. Originally a 2bbl. On a budget at the time, I put a used 4bbl intake and rochester carb from a Delta 88, and the hei from the 260 that was in my car. It ran ok. The real difference was when I tuned up the secondaries in the carb, put in a mild cam, (which only changed the durration of valve lift, not height), put a Mallory s/s coil on the still stock distributor, and I added a custom second snorkel to the breather.(see attatched) Now it rocks!, wants to let go going into second. All really inexpensive. I hope this adds to your possibilities.
Jim.

mitsudave

Go with the Performer RPM for a performance boost, and stick with a Quadrajet. Doing the cam isn't a necessity, plus it's a pain in the a** with the engine in the car. If you're upgrading the distributor to an HEI unit, I would stick with GM parts because they're proven reliable, and parts are readily available and inexpensive. You usually can't just walk into the auto parts store and buy a Pertronix module, but you can get a GM HEI module, coil, or any other part just about anywhere. I had a Pertronix point replacement module in my Olds for about nine months, and replaced it with a GM HEI distributor when it left me stranded about 30 miles from home. Also, if you're putting in HEI, you should also ditch the external voltage regulator and put in an alternator that is internally regulated.