Aries hi-performance muffler application.

[Great Lakes Greg]

I have been considering a hipo muffler from Aries. They advise against using one on a stock or modified engine producing less han 60 h.p.
I assume that would be because there is no disernible gain in power at that rate? It is also described as being slightly louder. Go deaf louder, or pleasently throaty louder? Thanks experts.

[Richard in Anaheim CA]

I have run one since they came out. I replaced a standard Aries muffler. I didn't notice anything dramatic in either performance or sound.

Richard
Anaheim CA

[pat in Santa Cruz]

Its not the muffler that is high performance, it is a muffler built for use on an engine that is high performance. Unless your engine is putting out higher volumes of exhaust due to greater intake volumes ( e.g, dual carbs, overhead valves, big cam), higher exhaust volumes ( e.g. the above and headers), and higher RPMs than a stock A engine, it would be a waste of money to put such a muffler on. The holes in the baffles are larger to reduce back pressure and accommodate the higher flow rates of a high performance engine . Any A engine under 85 hp should be fine on a stock muffler.

[MikeK]

I replaced a standard SS Aries that had snapped at the rear pipe weld with a HP SS Aries. If it is much louder, I don't notice during the only time I can really hear my own tailpipe- when driving out of, and backing in the garage. Nobody in the parking lot at club meetings or on tours or parades ever noticed or commented on the exhaust sound being different or loud.

Engine: Stipe 340 cam, 1.75 intakes, ported block with lifted seats, 8:1 cc'd/polished Brumfield superhead (160 psi cranking), Strom downdraft. The car measured 82HP on a rear wheel dyno with the standard Aries, I haven't checked it ($200 at speed shop ) since changing to the Aries HP version. If there is an increase, it's not much or in my powerband, I don't feel it. Then again, I don't wind over 4000 RPM. The only muffler difference is in the internal holes. They are about 1/16 bigger on the HP muffler. As you can see, I run well-tuned, lean and hot. There is no black smudge buildup in the muffler- just grey ash. O2 tailpipe probe when dyno'd said I was right on 14.7:1 air:fuel ratio (running E10) at 82 Horsepower peak. Dyno guy's (Young rice-tuners!), itching for 90, wanted to re-jet for 12:1 A.F.R., swap helmet filter for velocity stack, change plugs/ignition system & timing, go straight pipe exhaust. I said no!

In retrospect, having sent two SSAries back for repair of broken welds Read it HERE on Vince's website I would not use their stainless version. Examining the fracture location and grain, and then discussing the weld and alloys with Vince via email, it is apparent Aries uses a 300 series because it polishes well (Yuk on an A!) but it suffers at weld joints. Most OEM's use 400 series SS which does not polish well but has much better weld performance. The straight steel versions should not have this problem. Henry's butt welded mild steel muffler worked with a tight clamp, not a slip-fit clamp like Aries has you use.

On another note, I haven't seen a post from Vince recently.

[Tom Wesenberg]

"On another note, I haven't seen a post from Vince recently".

Vince is boycotting because he refuses to submit to the new body scan.

I've been wondering about Vince also. And, where's Marco?

[Benson]

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Mike K,

Did you ever check the A.F.R at idle?

I am curious what fuel ratio you find works well for a good idle?

I find 12.3 to 12.1 works better than a 13.5.


Thanks

[MikeK]

Originally Posted by Benson

Mike K,

Did you ever check the A.F.R at idle?

I am curious what fuel ratio you find works well for a good idle?

I find 12.3 to 12.1 works better than a 13.5.


Thanks

My idle A.F.R. is best at 14.0. I run a thermostat, so I'm always 165-175. Air swirl and turbulence in your head and plug placement also affect how well you can light off a small low pressure idle charge and how completely it burns, so the ideal AFR varies. Also, I always make a series of nicks on the leading edge of the throttle plate in the 1/4" that covers the idle ports. That helps generate turbulence, vaporizing the cold gas. A slight raised burr or ridge on the throttle bore, just past the idle opening will do the same thing, helping to lift the fuel away from the bore wall. I didn't learn that "nick" trick from any carb guys, I learned it years ago voicing organ flue pipes. Pipe organ builders understood air flow and resonance dynamics 100 years before the first carburetor. An organ pipe will "speak" it's true waveform much faster after air starts to flow past the languid if the mouth is nicked. Nicking Link Before I was into A's, I spent many years crawling organ chambers.

[Frank Miller]

I have watched many Harleys get dyno tuned. Straight pipes are great for wide open high rpm but nothing else. You can easily see how some back pressure will increase your torque and HP in the usable rpm range. You might lose a few ponies where you never drive to gain more where you do.

[Benson]

Mike,

Thanks for the good info. The engine is a fresh rebuilt Stock B (1500 miles, standard size valves, .040 over, Model A carb) with a Lion 7.0 head.

I borrowed 4 or 5 different Model A carbs that run just fine from engines with stock heads and the results are similar.

I guess maybe the strange plug location on the Lion head might be related to my rough idle problem from what you said in your post?

As an experiment I might replace the Lion head with a head "with the large B on it" or a Snyder 6.0.

Thanks

Originally Posted by MikeK

My idle A.F.R. is best at 14.0. I run a thermostat, so I'm always 165-175. Air swirl and turbulence in your head and plug placement also affect how well you can light off a small low pressure idle charge and how completely it burns, so the ideal AFR varies. Also, I always make a series of nicks on the leading edge of the throttle plate in the 1/4" that covers the idle ports. That helps generate turbulence, vaporizing the cold gas. A slight raised burr or ridge on the throttle bore, just past the idle opening will do the same thing, helping to lift the fuel away from the bore wall. I didn't learn that "nick" trick from any carb guys, I learned it years ago voicing organ flue pipes. Pipe organ builders understood air flow and resonance dynamics 100 years before the first carburetor. An organ pipe will "speak" it's true waveform much faster after air starts to flow past the languid if the mouth is nicked. Nicking Link Before I was into A's, I spent many years crawling organ chambers.

[JoeWay]

Originally Posted by Tom Wesenberg

...And, where's Marco?

Someone posted maybe a month ago that he was moving. I've seen at least one post from him since then, so I suspect he's quite busy but lurking on rare occasion.

Joe

[MikeK]

Originally Posted by Benson

Mike,
I guess maybe the strange plug location on the Lion head might be related to my rough idle problem from what you said in your post?

As an experiment I might replace the Lion head with a head "with the large B on it" or a Snyder 6.0.

Thanks

Before you yank that Lion head for the reason you state try an extended tip, reduced center diameter(fine wire) platinum plug, like the Autolite XP series @ 0.040 gap. About $7 each. The plug tip design greatly affects kernel propagation. Make sure your dizzy rotor gap is even at about 0.025 all around and check the evenness of the spark with a scope. Some coil/condenser pairings are unstable too, you might also want to check that. I assume you have no intake cracks or vacuum leaks. Cams with sluggish ramp-ups (big difference between zero lash and 0.050 duration) idle rough, too.

Yapp Lion Head:

[Larry Brumfield]

Originally Posted by MikeK

I replaced a standard SS Aries that had snapped at the rear pipe weld with a HP SS Aries. If it is much louder, I don't notice during the only time I can really hear my own tailpipe- when driving out of, and backing in the garage. Nobody in the parking lot at club meetings or on tours or parades ever noticed or commented on the exhaust sound being different or loud.

Engine: Stipe 340 cam, 1.75 intakes, ported block with lifted seats, 8:1 cc'd/polished Brumfield superhead (160 psi cranking), Strom downdraft. The car measured 82HP on a rear wheel dyno with the standard Aries, I haven't checked it ($200 at speed shop ) since changing to the Aries HP version. If there is an increase, it's not much or in my powerband, I don't feel it. Then again, I don't wind over 4000 RPM. The only muffler difference is in the internal holes. They are about 1/16 bigger on the HP muffler. As you can see, I run well-tuned, lean and hot. There is no black smudge buildup in the muffler- just grey ash. O2 tailpipe probe when dyno'd said I was right on 14.7:1 air:fuel ratio (running E10) at 82 Horsepower peak. Dyno guy's (Young rice-tuners!), itching for 90, wanted to re-jet for 12:1 A.F.R., swap helmet filter for velocity stack, change plugs/ignition system & timing, go straight pipe exhaust. I said no!

In retrospect, having sent two SSAries back for repair of broken welds Read it HERE on Vince's website I would not use their stainless version. Examining the fracture location and grain, and then discussing the weld and alloys with Vince via email, it is apparent Aries uses a 300 series because it polishes well (Yuk on an A!) but it suffers at weld joints. Most OEM's use 400 series SS which does not polish well but has much better weld performance. The straight steel versions should not have this problem. Henry's butt welded mild steel muffler worked with a tight clamp, not a slip-fit clamp like Aries has you use.

On another note, I haven't seen a post from Vince recently.

Nice post, Mike. I wish you would have used uppercase letters for the words "rear wheel" where it says "rear wheel dyno" or maybe said "rear wheel dyno (different as compared to brake horsepower output measured at the flywheel)" or something to that effect.

I suspect many readers may not know the difference. Thanks.

[pat in Santa Cruz]

I have a B engine, .060 over, lion 6.0 head, Holley 94, B cam and it idles like a kitten purrs. A new, tight engine can idle rough, spark gap makes a big difference.. I think the suggestions Mike makes are probably more likely to find the source than replacing the head. Lion heads are generally smooth running.

[coilover]

MikeK,
Do you know Dennis Piranio? You may because he is the source for the Donovan aluminum A/B engine. I would like to be a mouse in the corner if you two had a conversation on A's. He built a dyno dedicated to A's only and spends countless hours at his flow bench. He has a stock block A engine that is pulling 120hp on the dyno. The only visible mods are a header and two 81 downdraft carbs. I wish I had snapped a picture of the dyno but I did take a couple of his 29 coupe LSR car which he plans to bump the current record in his class by TWENTY mph, from 97 to 117 at Bonneville this coming August. His information on what an A needs for a cam will astound you.

[MikeK]

Originally Posted by Larry Brumfield

Nice post, Mike. I wish you would have used uppercase letters for the words "rear wheel" where it says "rear wheel dyno" or maybe said "rear wheel dyno (different as compared to brake horsepower output measured at the flywheel)" or something to that effect.

I suspect many readers may not know the difference. Thanks.

For those not in-the-know rear wheel brake horsepower is generally 15 percent less than the brake horsepower measured at the crankshaft or flywheel on an engine dynamometer. 82 HP at the rear of an A would be something like 96+HP on a dyno stand directly coupled to the flywheel. Dual downs and a different cam would push it over 100, but to me the width of a powerband is more important than some top number. Driveability and low speed street performance are part of the equation often overlooked by 'numbers junkies'. I actually went to the dyno to see the 'area under the curve' not just what the peak was.

[Larry Brumfield]

Originally Posted by MikeK

...but to me the width of a powerband is more important than some top number. Driveability and low speed street performance are part of the equation often overlooked by 'numbers junkies'.

So true.

An engine that produces high torque over a wide range of RPM will deliver more average horsepower during acceleration than an engine that delivers higher peak power in a narrow range of RPM.

[Benson]

Cool engine ... looks like he is using the two normal intake ports for exhaust ports And the four exhaust ports for intakes!

Originally Posted by coilover

MikeK,
Do you know Dennis Piranio? You may because he is the source for the Donovan aluminum A/B engine. I would like to be a mouse in the corner if you two had a conversation on A's. He built a dyno dedicated to A's only and spends countless hours at his flow bench. He has a stock block A engine that is pulling 120hp on the dyno. The only visible mods are a header and two 81 downdraft carbs. I wish I had snapped a picture of the dyno but I did take a couple of his 29 coupe LSR car which he plans to bump the current record in his class by TWENTY mph, from 97 to 117 at Bonneville this coming August. His information on what an A needs for a cam will astound you.

[Benson]

Mike K and Pat,

Thanks for your info. I read over your posts and decided to do the easiest thing first.

Recently I read an article in SSOS from 1994 (not sure of date) where Ed Winfield said that with 6.0 head the plugs should be gapped at .025 and for a 7.0 head they should be .022.

I did only one thing and that was to regap the plugs NGK (BP5ES) from .022 to .040. The difference is amazing! Idles and runs much better.

I will check into the other items you mentioned later ... I ran out of time!

In particular the Platinum plugs and distributor checks.

The B regrind cam is of unknown specs and the rebuilder, Mike Richter of L&M Babbit did not remember (2005 as I remember) any specs or anything about where it came from.

I should say for those of you who may know Mike Richter that he did this engine in 1989. Really sad see such a nice and talented guy go down hill so fast! He built many very good babbit motors from 1966 until the early 2000s.

I also reinstalled the 160 thermostat I took out last week when the engine was overheating. Did not have time for a road test. Engine temperature went from 130 to 170.

[SamIyam]

If someone knows the guy building the cage for that Model A Bonneville car pictured... let him know that he needs to put a halo bar in the car that is properly supported. Putting a dragster/funny car cage in a "door car" like that is not a good idea... reason being, in the event of a roll-over, the body will crumple in over that small cage and then he won't be able to get out.