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The mufflers that came with the system I bought are just perfect to my taste. No drone, not too quiet nor too loud. They make a very nice rumble at idle, and I can get the 'sleeping driver at the light' moving by revving the engine (no need for the horn).

Recommend the plug (GM OEM) wiring routing and the metal heat shields.

Here's some pics of dcairns 327/383 (just for info):

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CAUTION - this is probably more information than you want, but when you get me started on this topic... ;D

If you are wanting to dress your 350 up like a '63 327, the biggest obstacle will be the crank case breather system. I think all the 350's utilized valve covers with the holes in them for the breather and oil fill. The 327 used a hole in the rear web of the block, near the distributer for the vent (not sure in 63, may have even just been a draft tube). Also the oil fill tube from a 63 327 would be on the front of the intake manifold. After I did this, I heard of of someone getting much the same thing done with a hole in the intake manifold. Perhaps a more prudent choice.

When I started my restoration, I was going to try all this on my 350 based 383 that I had in the car already (put the 383 in there back in the late 80's). But in the end, I started wanting to keep it more stock looking than I could achieve with the 350 block, and had a 327 built, bored and stroked to a 383.



This is how a 63 block would look. On the right (front) of the block you can see where the oil fill tube goes. On the left (rear) you can see the vent tube hole, just above the distributor hole.
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Your 350 block would be like this (sorry, the orientation of the photo is flipped from the one above). You can see on the left (front), no oil fill tube provision. ON the right(rear) only the distributor hole, no vent tube hole.
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My old 360 based 383 with Quadrajet carb. You can see the vent hole and the oil fill cap on the valve covers
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I did start the process of making it look like a 327 by drilling the block for a tube that would give me a fitting in the location of the vent hole on the rear of the block
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Adding a '64 intake manifold and Carter AFB let me put on the oil fill tube. So at this point the most obvious give away was the larger stamp pad that the 350 had. But I did know the engine would need a rebuild, so this was just tinkering to see if it would work.
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But like I said, in the end I went with an actual 327 block. Since the 383 stroker cranks are large journal for 350 blocks, the engine builder put on a set of 350 main caps and had the mains line bored to match. So now the small journal 327 block could take the large journal 383 stroker crank
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Some roller hydraulic lifters, so no worries about cam break in.
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And the finished engine. I think this was before Vern Frantz gave me a few tips on a few details to get right. But a "327-300" with 370 hp and 420 torque. I love the easy power that this torquey motor has. I run the stock exhaust system with resonators. Has a slight rumble at idle and when you get on the throttle, a little roar as it gets up in the RPMs. Just enough to make a good sound track, but not loud enough to be annoying.
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Discussion Starter · #23 ·
Oh dang. dcairns, that’s a lot more involved than I thought. I definitely appreciate all the info. I may just keep the 350 looking like a 350 except the rams horn manifolds & alternator on the driver side like the 283s & 327s had(looks better in my opinion than the passenger side with ugly bracket). Japete where did you get the plug wire routing brackets?
 

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Personally, I like the clean look of the old style valve covers. If you don't plan on driving a lot with the car, you could get away with just changing the intake manifold to a 63 intake, with the oil fill tube. In 63, you would have had a breather instead of the cap on the oil fill tube. The breather would allow some flow of crank case fumes (anyone with more knowledge on this topic?). It would mean more frequent oil changes since contaminates would not be getting vented as well. But if you are not driving it heavily, your oil change routine is probably based more on time (like once a year) than miles driven.
 

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Oh dang. dcairns, that’s a lot more involved than I thought. I definitely appreciate all the info. I may just keep the 350 looking like a 350 except the rams horn manifolds & alternator on the driver side like the 283s & 327s had(looks better in my opinion than the passenger side with ugly bracket). Japete where did you get the plug wire routing brackets?

Wire looms, clip retainers, heat shields, etc are available from Show Cars.

Here's the clip retainers; other products are on same list of external engine parts:


Attached is a scan from the '63 Assembly Manual

Pete
 

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Discussion Starter · #26 ·
I ordered the manifolds & heat riser delete & gasket Thursday. The manifolds I orders from speedway & got here this Saturday morning, talk about fast shipping. I ordered the delete & gasket from shafer parts but they’re not here yet. Here’s a few photos. One step closer just waiting for everything to come in so I can go get a quote from the muffler shop.
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I wanted the more correct manifolds with the Gm stamping & numbers on the side but at $300-400+ each I said Noooo! These seem like they’ll do fine. I was pleasantly suprised they came with all the hardware & Gaskets. How hard is it to cut the ear on the passenger side?
 

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Don't know what you have for carb/choke. If electric auto choke, read no farther (not applicable).

The '63 auto choke used a 'clean air system' (I've attached a screen shot from the '63 Shop Manual).

Before you install everything (and think you're done) you will need to modify the right side manifold to accommodate the 'clean air system' tubing that runs through it. Dave (dcairns) I believe has done this. Perhaps you can ask him for some info/assistance. My engine has a electric auto choke so I skipped that mod.

Just info.

Pete

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Discussion Starter · #29 ·
Pete I’m running an Edelbrock 1406 with an electric choke so I won’t need to drill into the manifold for the draft tube I think it’s called.
I do need to figure out how to go about cutting the passenger side ear off the manifold. Maybe the exhaust shop can do it.
 

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I used a simple reciprocating 'swazall' with a metal cutting blade to cut as close to the 'base' of the bracket/manifold interface as I could. I ground (with a grinding wheel bitt on my electric drill) the remaining down to mostly smooth (but not all the way to the 'curved' part of the manifold. There is a tiny 'hump'.

Mine does not look as nice as DZAUTOs but after paint and installation (the 'cutoff' section is back by the #8 cylinder), I don't notice the 'hump' unless I stare at it.

I was surprised how easy it was. Consider taking a crack at it; I can't see how one could futz up the manifold. Unhappy with the final look? That's simply more/better grinding. Anyone with the proper grading tools should be capable of coming up with a very nice finished product.

Pete
 

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Discussion Starter · #31 ·
I think I will try it. I have a battery powered reciprocating saw with a couple of batteries & an angle grinder. Pete what type of paint did you use after you cut your manifold? I’ll post up the photo when I get it done hopefully😧🤞🏽
 

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I think I will try it. I have a battery powered reciprocating saw with a couple of batteries & an angle grinder. Pete what type of paint did you use after you cut your manifold? I’ll post up the photo when I get it done hopefully😧🤞🏽
I do not remember the exact product nomenclature. It was a simple Rustoleum High Heat paint and the color was some sort of gray.

For surface prep, I wire brushed rather rigorously, some elbow grease with steel wool, and a thorough de-greasing with gasoline. I found there are few if any de-greasers better than gasoline. Sure some may be safer, more environmentally friendly, but it is what I am used to using. As Eli Manning says in the commercial, 'I put that **** on everything'.

Pete
 

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Discussion Starter · #33 ·
Nothing to report yet as I haven’t received the heat riser delete plate & gasket. They’re on back order till who knows when. I wanted to wait till I had that & my manifolds(already have those)before going to the muffler shop to get a quote or two.
Hopefully soon.
 

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What have you decided regarding the exhaust downstream of the manifolds?

If you are going 'custom' (not suggesting you do), the 'space' taken up by the spacer could be accommodated by a custom exhaust pipe of the proper length.

Going OEM, the spacer, or the valve is required. The OEM exhaust pipe is not long enough to reach the manifold directly.

You likely already figured all that out. :)

Pete
 

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Discussion Starter · #35 ·
What have you decided regarding the exhaust downstream of the manifolds?

If you are going 'custom' (not suggesting you do), the 'space' taken up by the spacer could be accommodated by a custom exhaust pipe of the proper length.

Going OEM, the spacer, or the valve is required. The OEM exhaust pipe is not long enough to reach the manifold directly.

You likely already figured all that out. :)

Pete
I’m not going original but with the same basic layout/routing of the original mufflers & pipes. I guess I don’t need the spacer(I hadn’t thought of it honestly😂). I have been pondering the last two days if I should use mufflers with the same size inlet/outlets as the originals. I think I read from factory they were 2 1/2” inlet with 2” outlet. Would using 2 1/2” in & out somehow affect performance?
 

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I’m not going original but with the same basic layout/routing of the original mufflers & pipes. I guess I don’t need the spacer(I hadn’t thought of it honestly😂). I have been pondering the last two days if I should use mufflers with the same size inlet/outlets as the originals. I think I read from factory they were 2 1/2” inlet with 2” outlet. Would using 2 1/2” in & out somehow affect performance?

The 2 1/2" tail pipes will not hurt performance. Some folks opine that it improves performance. Me? I think that by the time the exhaust gets past the muffler, the 1/2" does not to matter (especially if it's just a street driver).

Chevy did not use anything larger than 2" even on the 425 hp 409. Or any other BB in the sixties (as best I remember).

The larger diameter tail pipes MAY (emphasis on MAY) cause some interference with larger than OEM tires. Details to look into. Make an informed decision. I'm not allowed to type the words I would utter if I found out my brand new tire' wheels wouldn't fit because I had 2 1/2" tail pipes ;).

Pete
 

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To expand a bit on what Pete was saying.. look at the dyno runs* and compare the "Stock 2.5" vs "Stock 2" HP and Torque graphs. Depending on where you look, it seems to only cost about 7-10 HP**
These compare stock 2.5 inch manifolds with a 2.5 inch down tubes about as long as the one feeding into the muffler. The "Stock 2.5" is just that, 2.5 inch pipes to the end of the down tubes. The "Stock 2" had a 2.5 to 2 inch reducer placed on the end of the down tubes, much like happens with the stock exhaust where the 2.5 inch down tube is reduced to 2 as it enters the stock muffler.

* This engine is my 327 (bored and stroked to 383) that used stock intake, block, heads, exhaust and a slightly larger bore Carter AFB that was used on one of the 409's in '64.

** This does not take into account the muffler and down stream tail pipes. It is unknown from these runs, if there is any difference between a full 2.5 inch system (mufflers and tail pipes) vs the 2.5 to 2 inch stock system

*** If you are curious, the last run "Stock 2+AC" added the stock air cleaner in addition to the 2.5 to 2 inch reducer.

 

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If you are going for a loud exhaust system, I find oversized exhaust pipes make drone much worse. I size the exhaust based on the engine size/output, there are plenty of resources on the internet that discuss such things.

But I'm also more concerned with drivability/livability/tone than I am with outright power.
 

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Discussion Starter · #40 ·
I took the car in to the exhaust shop(Mitchell mufflers, Modesto ca) & got it back today. I couldn’t be happier, they did an awesome job.
Magnaflow I think 40 series, 2.5” inlet/outlet & sounds just right. The car feels more potent & gets up to speed much easier than before. It used to feel “restricted” with the, I’m assuming original 2” manifolds left over from when the car still had the factory 283sb. The car has a “death wobble” when driving at higher speeds which I’m assuming is partly suspension related but even that seems to of mellowed out some.

thanks everyone who chimed in.
 
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