First start question reguarding exhaust manifolds

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prorac1

prorac1

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We are putting together a 318 with a cam for my sons 1963 valiant.

Here's the question.

We are running the factory 64-66 273 exhaust manifold on the drivers side, and a 1967 a body 273/318 exhaust manifold on the passenger side.

We are going to have to start the engine and immediately break in the cam and set timing.

Can we do this with these manifolds open? I'd rather get it running before bringing it to an exhaust shop for exhaust.

Never fired a new (ish) engine through wide open manifolds before.

Thanks. Eric and Jason.
 
Sure you can, but it is always a good idea to run exhaust before hand so you can actually hear the engine itself. Open exhaust assures you might not hear some noises.

Also, have your timing light attached and ready. When it fires off, run the RPM up to about 3000-3500 and pull the timing up to 36* at that RPM and break it in like that. All too often, new engines are started with retarded timing.
 
i don't like to do it that way because the exhaust can block out noises that may indicate a problem with the motor. Having said that, the last motor I fired up (an original 318 that came with my project car and after changing all the gaskets first) was with exhaust manifolds only. Of course, in my case no cam to break in, either.

I did have the car towed to the muffler shop later because the drive would have been an hour and I wanted to make sure I could monitor sounds/noises on the unproven 318. Good news is I put almost 10,000 miles on it since then during 3 yearly road trips without a break down.
 
Better have an oil pressure gauge working, And keep an good eye on it.....As stated, you could blow the whole dang thing and not hear it
 
It has to have exhaust anyway, so why chance it? Tow it to the shop and let them have at it. Or do it yourself......whatever.......just have exhaust on it first. JMO.
 
Since I've done it the other way and didn't enjoy it, I wanted exhaust on the car before we started it. Got downpipes from accurate exhaust and bolted Mufflers up to it. It's a lot more pleasant to hear when you have to run it for 20-30 minutes.
 
RustyRatRod said:
It has to have exhaust anyway, so why chance it? Tow it to the shop and let them have at it. Or do it yourself......whatever.......just have exhaust on it first. JMO.
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Best way......IMO as well.....
 
Had my brother (a welding student) weld some some flanges on a pair of glass packs (temporarily) so I could muffle the fenderwell headers on my '65 four door Valiant bracket racer during start-up and driving to the muffler shop (30 mile trip).

Without tail pipes or muffler hangers, Dad helped me support the glass packs on each side of the vehicle by wrapping chains thru the two rear door handles. Kind of a hillbilly way to do things (lived on a cattle ranch at the time). Salinas cops stopped me on the first day, and chewed my *** out, but let me go.
 
That has kinda been our dilemma.

That was my first thought. Tow it to an exhaust shop, and than tow it back home for first startup
 
I broke in a 351C with open headers half way out of my dads garage in his condo complex. Jeez, did I hear it from him after he got home that night. I think everyone complained for 3 streets around.
 
My two schools of thought:

-A new engine for a race car is usually started without an exhaust system.
-If it's going to have an exhaust system eventually, put something on it before you start it.
 
pishta said:
I broke in a 351C with open headers half way out of my dads garage in his condo complex. Jeez, did I hear it from him after he got home that night. I think everyone complained for 3 streets around.
Click to expand...
BUT open headers sound a lot different/better then manifolds...IMO
 
I usually try to get a couple feet of pipe onto manifolds,they y-pipe or a cut up y-pipe.
Headers-wide open. Road test!
 
come one man
with all the work you guys have been doing to his car, just do the exhaust first
i think i paid 250 for my kit from summit
add a few bucks for the downpipes and get her done
 
Maybe something else to consider., I know your weather up there has been as brutally cold as down here. If you are doing this outside or in an unheated garage, it is a possibility when exposing hot valves to zero degree temps, there might be a chance of warpage. I personally would not chance it. But hopefully you are in a controlled climate. 2¢ happy new year
 
Yeah. We will probably buy a couple summit 2 chamber welded mufflers and find a muffler shop to bend it up.

Would have been easier to load the car on and off the trailer twice while running. Lol.

Just being lazy. Lol
 
Dana said:
Maybe something else to consider., I know your weather up there has been as brutally cold as down here. If you are doing this outside or in an unheated garage, it is a possibility when exposing hot valves to zero degree temps, there might be a chance of warpage. I personally would not chance it. But hopefully you are in a controlled climate. 2¢ happy new year
Click to expand...

Oh yeah. Definitely climate controlled while working. Lol. I'm not working outside in this crap. Lol.

This 5 degree crap is for the birds and I'm over it. Lol
 
diymirage said:
come one man
with all the work you guys have been doing to his car, just do the exhaust first
i think i paid 250 for my kit from summit
add a few bucks for the downpipes and get her done
Click to expand...

Problem is summit dosent make a kit for the early a bodies. So we're kinda at the mercy of the bender for our dual exhaust.

I'm thinking 2.50 duals should be more than enough. Maybe even 2.25
 
prorac1 said:
Oh yeah. Definitely climate controlled while working. Lol. I'm not working outside in this crap. Lol.

This 5 degree crap is for the birds and I'm over it. Lol
Click to expand...
Well I totally agree with you, but I don't think the birds do!:D
 
prorac1 said:
Problem is summit dosent make a kit for the early a bodies. So we're kinda at the mercy of the bender for our dual exhaust.

I'm thinking 2.50 duals should be more than enough. Maybe even 2.25
Click to expand...

Go ahead and go 2.5. That way, if yall ever upgrade to a larger engine, the exhaust will already be there.
 
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