72GoldOlds350

Hello fellas!

Quick backstory:

I currently have a 1972 Cutlass Supreme with stock Olds 350/TH350 combo. Mark is currently building me a stout 434ci build (with aluminum heads, cam, etc.) and I'm trying to get the exhaust system ordered to install the same time I install the new drivetrain in it. Currently, the car has an unknown aftermarket (looks like a Pypes or Flowmaster set-up) with shorty headers. It sounds bad, lol.

My question:

Lets assume money is not the 'issue' - what is the best dual exhaust cat-back style exhaust system made for this car? The new motor will have long tubs, and I will also be installing electric cut-outs after the headers. Since the build will have cut-outs for the strip/fun, I was hoping there was a cat-back system that was more 'quiet' and modern sounding, considering I can use the cut-outs when I want it loud. Since this new engine is going to be much more louder and aggressive, naturally, I think it would be too loud with something like a traditional/cheap Flowmaster system, etc.

Basically, I want it to be heard and deep, aggressive, but not that hollow/glasspack loudness - since that will be what the cut-outs or for.

Any insights?!

72GoldOlds350

The two I've narrowed it down to, albeit I'm not sure how loud the ARH system is, where it seems the Magnaflow is half the price and its noise-level is 'moderate,' which may be what I'm looking for:

https://americanracingheaders.com/co...72-header-back

https://www.magnaflow.com/products?partNumber=15894

Fun71

There are none. Your car never had catalytic converters, hence no "cat back" exhaust system exists.

I would go with at least 2.5" diameter pipes and Walker Super Dynomax mufflers. From what I have read over the years, Hooker headers have always worked well on performance builds.

cutlassefi

coppercutlass

ON the street I would not worry about an exhaust too much to be honest as far as performance goes. you wont feel the difference. I run an X pipe on my 355 with hooker areo chambers. At the track I unbolt the entire mufflers off and run an open x pipe. Usually only worth 2 teths in E/T or roughly 20hp. I always recommend an x pipe and if you don't wanna unbolt mufflers for track use then I suggest installing cutouts after the x junction. Careful placement of the x pipe is crucial to make HP with it. ON the street I wouldnt get too hung up on muffler choice. The older I get the quieter I want my car but when I run it at the track I know what I want. Hooker areo chambers sound killer BTW. Here is a clip of y car cruising aroun town with them and also getting on it at about the 442 mark oddly enough lol.

olds403

olds 307 and 403

What motor and how were the down pipes in particular? The Hooker Aerochamber mufflers are loud but have a unique sound, I moved a 2.5" system from my G body short of the tail pipes, which I got custom bent, wouldn't do that again. I am considering the Chinese full length stainless headers since I have a ton of ground clearance and already have a double hump cross member. I am thinking Hooker Maximum Flow or Magna Flow mufflers as I am putting that system back on the G body, it has droning on my 70S. Flowmaster makes tail pipes in 2.5" regular and stainless and 3" as well I believe. Unless you are planning a crossover pipe, the header back pipes on full length headers should be basically straight pipes, should they not?

72GoldOlds350

Thanks for the tips, everyone!

I'm pretty sure I'm going to get Hooker long tubes and the magnaflow cat-back

72GoldOlds350

Update; looks like we are going to change carbs to a QF830. More to come soon!

olds403

Hello,

the downpipes came from ram air restoration. This is an F-body with an Olds. Pretty much we share everything, but the tailpipes. This system is a Olds Cutlass downpipe from RAM Air, Pypes center pipe, Dodge charger 2008-2010 Walker SS mufflers, and Pypes Tail pipes.
I know RAM Air makes a cutlass set up as that I how I harvested the downpipes out of it. Hope that helps clarify a bit.

olds 307 and 403

Those Ramair downpipes look like they fit very well with nice mandrel bends. On stock manifold's? I am very curious if Thornton's BBO manifolds hit everywhere W/Z manifolds do on a SBO, they would be perfect for this build and mine as well with those Ramair downpipes.

olds403

olds 307 and 403

Thanks for the little details. There is a argument if there is any gain with those manifolds, of course people say the same thing about shorties. I like the Thornton SBO polished stainless shorty headers for a 350 with 2.25" factory downpipes, should be perfect. For a SBO, now some 420+ ci and 9+ to 1, 1 5/8" primary and 2.25" outlet, which can't be enlarged is small for those motors. The BBO version with a dent here, spacer there and a Rocket Racing oil filter adapter might fit their 1 3/4" with 2.5" outlet with an actual collector. Thornton BBO polished shorty headers on a SBO with more cubes is more suitable.

olds403

72GoldOlds350

Looks like I'm going to be getting some ARH Long Tubes fore the motor when it is finished - so I'll just have to figure out what true dual exhaust I'd want hooked up to it with quieter muffles for the street, and cut-outs for when it's time to get rowdy!

olds 307 and 403

With the cost of mild steel coated Hooker Procomp headers, ARH aren't that much more. I say big body Dynomax Super Turbos or even Quiet Flow stainless mufflers.

Firewalker

Many ways to have power and be silent, and many ways to screw things up. Put mufflers at the rear, if you can fit them there. Cooler gases will flow through easier there. It also put's the added weight close to the rear bumper.(traction) The largest super turbo style 2 1/2 muffler I know about are the Walker Exhaust 22100 Quiet-Flow SS Mufflers. To be super quiet and get super flow run 2 side by side on each bank.

For just good but a little lesser flow and very quiet, run the aero chambers, with these quiet flow mufflers after them.

For max power I would use 1 7/8 headers and a 3-3 1/2 18 inch header extensions, and then reduce down to 2 1/2 for the mufflers.

70cutty

My car has ARH headers 1 7/8 primaries and 3" exhaust all the way to the back bumper. I had custom mufflers which were way too loud, now I'm using Dynomax Super Turbo mufflers and they are just sweet music to my ears. Deep but subtle rumble at idle and low rpm, gets louder as I step on it. the link is to the video, it's kind of crappy but you can hear the car.

72GoldOlds350

That was my thought! Thanks for the tips.

Right on, I appreciate the recommendations!

She sounds great! a 'little' quieter than I planned, but it sounds wonderful! May I ask, is your motor stock? Because if it is, my engine build is going to be pretty aggressive, thus that same setup would be perfect, in that case.

70cutty

Thank you, they are mild at idle and lower rpm but they get more aggressive as you step on it. Mufflers were brand new in the clip, they are little louder and deeper now.
Trust me the loudness gets old really fast, especially the drone. I was planning on cutouts but I don't think I want them anymore, I really like the deep rumble that these mufflers have.
My engine is a mild 463 built by Mark about 5 years ago.
Nothing fancy
Icon 886 pistons .040
Eagle rods
Lunati hyd. roller 234/242 582 lift, on 110 lsa in on 108
Bernard Mondello ProComp aluminum heads,
Performer Intake
QF 850 DP
10.3:1

72GoldOlds350

How beautiful! And thanks for the video clip, too. I like how that exhaust ended up sounding very much.

70cutty

Thank you!!

72GoldOlds350

Well, once the engine is (hopefully) installed in a month or two, I will keep everyone posted on the direction I decide to go on! Lots of helpful ideas on this thread, so I thank everybody for that! More to come...

Spoffie1962

If you want to run fairly quiet on the street but make noise on the track, your best bet is to use this http://classicmusclecarexhaust.com/p...11-no-mufflers with these mufflers http://classicmusclecarexhaust.com/p...turbo-mufflers and this electric cut-out kit http://classicmusclecarexhaust.com/p...touts-pyphve10. Best of both worlds. You really can't go wrong with Dynomax Super Turbo Mufflers. They come in 3 different case lengths, 14"-16"-20", so you can chose your sound level. I know someone with this setup on a GTO and he loves it.

72GoldOlds350

Side note: I see you removed your OEM voltage regulator that mounts on the firewall. I'm trying to clean my firewall up, and my new/aftermarket alternator has an internal regulator, but everyone tells me that even that the new alternator is installed, I can't just simply 'remove/disconnect' the OEM regulator...?

svnt442

If he changed the harness to one for a 442 it would eliminate the regulator.

olds 307 and 403

I just went with a 70 amp chrome factory 10DN replacement from Summit on my 70S. The performance tag showed 53 amps at idle and 82 amps at cruising speeds, plenty for me. As said basically if you wire the idiot light or gauge in properly, any alternator will work. Make sure you get an actual 12SI case, not 10SI if going with 100 amps or above. The 10SI can't remove the extra heat generated and don't last more than a couple of years.

72GoldOlds350

Side note, if I got the AR long tube headers, how easy would it be to install myself? I do not have a lift.

Spoffie1962

Are you referring to the headers or the crossmember-back exhaust system? Or both?

72GoldOlds350

Headers

olds 307 and 403

Easier with the motor out of the car. Put the headers sort of in place and drop the motor in.

72GoldOlds350

Engine will be in the car when this happens, unfortunately. Will it be doable from underneath the car if the car is in the air a foot or two?

olds 307 and 403

Yes but the oil filter adapter needs removed. Trans lines, brake proportioning valve or loosening the motor mounts etc. Are you running the current exhaust for now?

72GoldOlds350

Yes, I will be. I've depleted my 2019 car funds after this new engine, trans, GV overdrive, new driveshaft, etc. build.

72GoldOlds350

Guys, where do I get an air cleaner like this one?

Orlando 1

Those videos with the Olds sound, I can go for days listening to 'em.

The first one:

It sounded a lot like my 68 Cutlass with 350 after I put the 1-5/8 full length headers (Hooker) and dual DeltaFlow mufflers, with 2-1/2 pipes front to rear (Flowmaster).

One I found in a web search, skip ahead to 3:00 for the muffler sound:

coppercutlass

Current 355 olds with solid cam and just an open x pipe while i was doing some work underneath. That video I shared is a few years olds.

oddball

I have the ARH headers with a small block and have R&R'd them about a dozen times. Really nothing special, but here's a full breakdown to save you some time.

To install:
Remove starter and oil filter adapter.
Lift car in the air on 6 ton stands about as high as they will go. You need a LOT of room at first.
Angle the headers vertically and slide them in. They'll go.
Once they're laying in place you can get the car down to a more reasonable height.
Bolt the starter in place BEFORE bolting the driver's header. You can maneuver it in there while the header is just laying in place.
Don't install the top bolt. We'll ignore that from now on and just talk about the 4 inline bolts.
The rear-middle (third from front) bolt on each side is the worst. You'll need to put the bolt in place in the header, put a ratcheting wrench on it, THEN position the header in place and get that bolt started. The tube is so close that you cannot start this bolt if any of the others have been started. Go ahead and run it down most of the way.
The front two bolts are easy. The rear bolts are usually easier from underneath.
Reinstall the filter adapter.
Reinstall the trans cover last. I usually get the passenger side in place, then fold it onto itself on the starter opening and shove it up there. The top bolts can be reached with a wobble or with a ratcheting wrench.
I regularly argue with my buddy about whether it's easier to attach the starter wires while the starter is loose, or after everything is bolted in place. You need a wobble if doing it at the end. I prefer doing the wires last - at least the starter won't be moving.

Removal:
Pretty much the reverse. The third bolt needs to come out *last* or else the wrench will be caught in there.

Other notes:
Removal is easy - can be a one person job because gravity does half the work.
Install is much better with two people. One on the ground moving the end of the header and working the last bolt, and the other up top lining up the front three bolts. I did an install by myself once and it took a very long time.
No need to modify brake lines!
I've never had to unbolt the engine mounts or lift/tilt the engine or anything.
I've had best luck with Remflex gaskets. YMMV.
You need the mini Powermaster starter. 9510. It doesn't have an R terminal for the ignition, so you need to update your wiring if you haven't. Wrap the starter wires in some heat shield. The starter is fine without anything.
I switched to 5/16" 12pt head header bolts this last time and bought a tiny 5/16" ratcheting wrench. Every little bit of room helps, especially since I wrapped the headers.
Slip-fit joints aren't all one would hope they could be, so I welded on Marman flanges (kind of a cross between a V band and a ball flange) this last time.
You may need to trim the ears on the transmission! Take a look while everything is together and see how much material is actually useful. You can just use a sawzall or whatever to lop off some of the ear. Same on the inspection cover. I have a love/hate relationship with those inspection covers..... As long as there's enough material for the cover to bolt on then you're fine. I also remind myself that those covers will, eventually, self-clearance.

72GoldOlds350

Update: I've decided to order the Magnaflow crossmember-back kit, especially after hearing some good quality video clips. I'll post some of my own in a few months when the installation is complete!

Spoffie1962

$50 off that MagnaFlow system (and all systems) right now - http://classicmusclecarexhaust.com/