my71olds

Hello

What are the opinions on headers? I have a 71 cutlass with the 350 and dual exhaust. Do you think headers will help with performance/more HP?

Thanks

my71olds

Any suggestions are welcomed!

oldcutlass

Long tube headers are an improvement over stock exhaust. Will it register on the butt dyno, probably not.

Olds64

Eric is correct. Your butt dyno will probably not be able to tell the difference. It will change the sound of your car's exhaust note though.

Be prepared to change header gaskets. They can blow out, especially if you buy a set of cheap headers.

olds 307 and 403

You are looking at 15-30 hp and torque dependent on short or long tube etc. The Sanderson shorty headers fit nice. What size pipe is your dual exhaust?

joe_padavano

First, the more air (and thus fuel) you can move in and out of the engine, the more HP it will make. Proper tuned full length headers have been proven time and time and time again to provide about 20-30 HP increase over stock manifolds. More importantly, this improved exhaust breathing is an important foundation for any other performance upgrades you plan to make. I personally wouldn't waste my time with shorty headers.

Fun71

I much prefer headers over factory manifolds as headers will flow a lot better than the factory exhaust manifolds. I have a set of Heddmans on my car and they have held up well over the past 30+ years. No gasket blow-outs, loose bolts, etc.

Is your '71 350 still in factory form (8:1 compression and puny camshaft)?

wcourt3010

Go out and get yourself a pair of hookers. Headers that is.

my71olds

Yes still in factory form

Allan R

IMO if all you're planning to do is look at upgrade to an existing dual exhaust? Not worth your time and money. If you're planning to change intake, cam, lifters then I'd consider the headers
It all comes to how deep your pockets are and what your plans are for using the car. Show car? Nope. DD, maybe. Performance, yup.

Allan R

except that no 71 CS verts came from the factory with deck wings, and those side mirrors appear to be one year only 1970.

my71olds

its a 71 and the spoiler was added not by me

my71olds

I was talking about the engine

Allan R

One other thing you'd have to consider is moving the brake distribution valve if you put headers in. Check the location and you'll see what I mean.
Sorry, I apologize for the other comments. I thought you were talking about the car in general.

olds 307 and 403

If you put in Sanderson shorty headers, nothing need moved, you just need custom down pipes. They are much roomier than in my Gbody.

my71olds

What part # for your Heddmans? Full length right?

Thanks

Fun71

Not necessary on small blocks, but may be required on big blocks. The Heddmans fit without relocating the valve on both my 70 and 71 with 350 engines.

Fun71

Not sure about the part number, I bought them back in the 80s. 58150 comes to mind, but again, it's a memory from last century.


And yes, full length.