Question on exhaust

I like that, but it looks like you have to remove an awful lot of stuff to adjust the valves.

Lane

 

If these cars are like mine, Henry has the exhaust system set up so that you just have to remove a bolt of two, and the system swings down and out of the way for valve adjustment.  I have not tried it as yet, but I assume this means having the car on a lift, or high enough to allow the system to clear the valve covers.

 

I'm waiting for decent weather to allow me to take a good look at this.  I didn't bother back in the summer, of course.

I really like the dual tips in the second photo.  Very nice!

what is that lower valance add-on?  Is that for aesthetics? it looks very close to the exhaust.

I spoke for about a half hour with Tiger today at A1.  What a nice guy.  Great suggestions.  They have ways of adding a simple under dash trigger to bypass muffler, other exhaust systems, different mufflers etc.  BUT i believe i have a great compromise on all of this.  Because i want some additional sound and more aggressive sound at certain times...I may not want it all the time like some of you said.  The a1 sidewinder is a pretty simple plug and play exhaust...15 minutes to take off and bolt on with its design.  This is of course according to Tiger.  For under 300 bucks, I am looking at getting another ceramic coated center exit black exhaust that will have a race bullet muffler.  This way I can swap them out anytime i want to go silent or hear noise!  Seems easy enough...

both systems above would be easy to bypass the muflers.

Speaking of, has anyone tried a dynomax VT muffler? They have a flap inside that's closed under light load. Supposed to keep things quiet at idle and cruise. Wondering if they live up to their hype.

I wonder how long it will last. also some of the oe mufflers also have that feature,but the ones I saw were so tight Im not sure a 540ci big block could open them before it were choked down to far.

  there are a lot of forces going on in a exhaust system/muffler, both positive & negitive pulses,it can and does beat the crap out of a muffler&any thing in it that can move.

   many moons ago when walker first came out with thier super turbomulller with the "parabolic" chamber ends&built in turns for the exhaust inside the mufflers, I got a set 2 1/2" and stuck on the rear of my street car, they sounded great,the power was great, but after I spun it up past 8500- 9000 rpm 2 times all the guts were just ratteling around in them, so I got out my trusty hole saw and cut a 3" hole in the end caps, snatched all of the guts out then welded the hole I had just cut shut with another peice of sheet mettell. the car was louder, ran about the same, and are possiably still on the car. 20 years ago+ a few more. Im gladd flow master came along.

I looked at those online last night.  Very interesting, but I always worry about this 'fancy stuff' not working properly after a couple of years.

 

so for 1 why dont they show the other chamber? and 2,  they should make it tuneable for diferent engines & ears, just a adjustable tension nut that can be axsessed for the outlet or inlet and you could tune it to your ride& your style. I think the one I saw was from a new camarow vert car, I could hardly open the butterfly with my hands.

You guys are too kind. Terry, Bob, Rich-- there'll be a little extra sumpthin' sumptin' in your check this week.

 

To be fair to the discussion- there's one exhaust that stands head and shoulders above everything else: the Tangerine Racing Tri-Y (Rich has one on his car). Those guys REALLY understand exhaust theory, and are building something nobody else is even attempting. I've run with Rich's car-- it's fantastic sounding.

 

What I've got is two mufflers in series, with a bypass valve ahead of both-- I can run in the "model-citizen mode" (through both mufflers), or "juvenile delinquent mode" (open pipes). Both options exist out the back of the car. "Model-citizen" is loud-ish but restrained (until provoked). "Juvenile delinquent" is just plain nasty and raw. Top down, I open it up just to hear it cackle like a hyena.

 

The thing to remember is-- the exhaust isn't just about sound and fury, it's an important component in tuning the engine. Different combinations respond quite differently to differing header primary tube lengths and diameter; collector shapes and dimensions; and most easily overlooked, to differing exhaust pipe lengths and diameters.

 

I recommended a book by AG Bell on another thread called "Four Stroke Performance", which has a chapter on exhaust theory I tried to follow. To be brief, what happens after the collector (before the muffler) in a 4/1 header is pretty important. If a large enough chambered muffler is installed, it acts very similarly to a stinger (which continues the scavenging effect of the header). It's free power-- and if done correctly, sounds great too.

 

My first is a big chambered muffler, chosen for this reason. The second muffler is just a turbo muffler, chosen for sound attenuation. It sounds pretty good- my contention is that the length of the exhaust is almost as important as what kind of muffler is used.

Hence why the first "muffler" in such a setup is called the resonator or terminator box. You're tuning the collector length (resonant frequency) with it. They're usually just an empty box, but any decent increase in cross section (or CFM) compared to the collector will act the same. You can do whatever you want with the exhaust after the resonator without affecting the tuning as long as it flows at least as much CFM as the collector did.

 

If you only have one muffler then the collector's tuned length depends on the CFM rating of the muffler. If the muffler flows more CFM than the collector, then then mufflers input looks like open air to the collector. If the muffler flows the same CFM as the collector then it's as if the collector runs all the way to the end of the tailpipe. You don't want a muffler that flows less CFM than the collector. If it does, you need to find a muffler with more CFM or use dual (parallel) mufflers instead. That's the nice thing about a resonator box, you don't have to worry about this stuff. Just throw oversized (CFM-wise) pipes and mufflers after it and you're good.

 

But again, you have to be pretty serious about chasing HP to worry much about this.

Quick story... I was 3 cars behind Stan on a country road at a stop sign. He made a left and hit the throttle in "juvenile delinquent" mode. Wow!

 

Followed Rich as well and his car definitely makes a great roaring deep throated growl as well.

 

Now you got me thinking about tearing off my exhaust and starting over... 

Stinger

A stinger gets old really fast. If you do any long travelling at all you'll be stopping for earplugs pretty quick, and I don't know what it's like where you live but around here something that loud draws law enforcement like bees to honey....

Stan, what diameter is your exhaust tubing after the collector?  Presently, mine is 2.5" from the collector to the muffler.  My new system will go from the collector  to the muffler, then to another muffler and out the back of the car.  I'm wondering if I should stay with 2.5" or go down to 2.25".

with too big of a tube the pulses stack up like a freeway mess, smaler tube they tend to stay in line and keep going the direction there supposed to be going.  just for instance I put a 2 1/2 system on my wifes honda (2.4 L  motor), it has 1 3/8header, and 1 11/16" exhaust system, I knew the 2 1/2 would be too big, but wanted to try it. well the car was a real turd with the big system, it wasent on there for 2 weeks,I couldnet get it off fast enough.if I was racing it at daytona it might of been ok... a big system is not just like a stinger, it does nothing like a stinger.for a street vw with up to a 2276-2332 I would not go biger than 2" out of the collector & no biger than 2 1/8"true muffler core size.and not smaller than 2"core size., big tubes look good.but do you want good looking tuna or tuna that taste good.I can tuna car, I can tuna fish, but I cant tuna piano.

What's the I/D of the collector at it's smallest point, Ron? Also, what is your best guess on H/P for your engine?

Just as a comparison, I just measured my Berg dual quiet pak extractor.

 

2" diameter coming off of the collector for about 2-1/2" length.  That short section has a vertical divider welded in just behind the flange.  

 

The mufflers are horizontal, left and right and are connected together in a very shallow "Y" at their collector flange, which has a corresponding vertical divider at the flange simply by welding the pipes together in a "Y", although it has clearance to allow some scavanging to take place.  

 

Each side has a 1-1/2" pipe (so the combined pipes are, effectively, larger after the collector ).  This has the same effect as a small expansion chamber after the collector.  The pipes through the muffler and out continue the same 1-1/2" size.  This effectively broadens out the torque band a bit and seems to work very well about mid-range RPM (2,500-4,500).  My only gripe is a drone around 2,500 rpm, so I just shift down to keep it around 3K or higher or, if it's level running, drop it down towards 2K with a light foot.  Other than that, it's sort-of quiet, much more so than many at Carlisle but a lot louder than an original 356.  I've lived with it for 12 years now, but have been playing with running different mufflers to get closer to the original's sound level....I'm just afraid of what Mark found:  Run something quieter and suddenly turn your performance to sludge.

the system I was refering to wasent quieter ,pretty much sounded like poop to me&the wife hated it. sold it to a young guy for what I paid for it and he is happy as could be with the noise it makes.nobody makes a stainless system for the honda element that is the right size, everybody want to "lookkool" with big pipes that just hurt performance on a lower rpm street motor (below 5000 rpm, most of the time).so Ill make one my self when I get time for hers & for mine.hers is simple,these 356's might not be so simple.and I too want the best of both worlds, super quiet mode(as I get a lot of migranes)and top fuel mode. I do have sme 4 or 5" polished stainless exhaust tubing I had thought about making an oe appering type system , but thats still up in my head floating around. it just takes time, energy&cash, none of witch I have a lot of nowdays.

    just remember a big motor with a soso exhaust will overcome a small motor with a great exhaust. all this thinking is exhausting.

 on another note, I was working on a race boat turned pleasure boat(40'douglass skater with twin supercharged 1000 hp motors) it belonged to tony george(indy speedway) he had it converted to pleasuer boat but hurt his back & never used it,so it went into the showroom for a while, a friend of mine bought it and briung it to me to fix it so he could run it, I did, it was awassom 140+mph, felt like you were riding on a bumbles back from the serface pearcing 5 bladed props, but the boat also had some new all stainless mufflers that came with it,there things were humongus about the size of 30 gallon cans, all polished, oh so sweet looking,and about $12000 per motor from what I was told.well after a while I instaled them to see what they sounded like, holy crap they sure quieted them down a lot, and for about 20 minuts it was snowing white fiberglass packing, I havent a clue as to how they got that much stuffed in to them & weather that left out a bafflell or what but that stuff was coming out like a blizard.when the owner showed up & herd it he said take that **** off!!! so I did.I got him used to the way the skaters handled and he was happy with the boat.so much he decided to start racing. he won the world championships a few years, I havent seen him in quite a while I dont have a clue as to what hes doing now. so whats this story about?? dont be fooled by fibergalss packing, it dont stay very long in most cases. and the sound does change.some use stainless steelwool packing witch I think would last longer.

Area is radius squared times pi, not diameter squared times pi.

pie are round, cake are squared. Nfld joke....

Ron-

 

Are you saying that the smallest point in the collector is 2-1/2"? And that your primary tubes are 1-1/2" O/D? If so, that is not at all normal (and a pretty bad design).

 

Generally a 1-5/8" primary tube header will be no more than 2" at the outlet of the collector (and often necked down to 1-3/4" or smaller). If it is the case with yours (that it's BIG), the pipe between the header collector and the muffler becomes really, really critical (like TOO critical).

 

Take off the pipe at the collector ring and measure. It's pretty important.

No, I thought Gordon's collector opening was 2.5".  I just reread his post and realized he wrote 2.0".  My bad.

I'm going to delete my previous post, because the numbers are all wrong.

 

My engine and exhaust system is a my mechanic's shop, so I can't measure the collector opening.  It's a standard merged header, so the opening is probably 2.0" or 2.5".  I do know that the pipe coming off the collector has a 2.5" diameter. 

 

When I had the exhaust system made, many years ago, I had the fabricator shorten the merged header (can't remember by how much-probably 3 or 4 inches) so that it didn't stick out so far.  This was before A-1's tuck-in system was developed by Tiger.

I've always wondered if shortening the head affected the power output.

Ron-

 

I have a guess here.

 

I'm guessing it was a standard Bugpack (or something) merged header before it was shortened. If you took it to an exhaust guy, I'm guessing what happened was that he cut off the small collector flange, and as much of the collector as he needed to weld on a large 3-bolt (B/B Chevy) flange.

 

I'd guess you have a 2-1/2" collector, dumping into a 2-1/2" head pipe. If that's the case, it's too big and you aren't scavenging for spit. If this is what you've got, you are leaving a lot of power on the table, and you probably have considerably less "snappy" throttle-response than you are paying for with the engine. I wouldn't be surprised if this is part of your running so hot as well.

 

I understand what you were trying to do by shortening it. I notice that the body on your car is cut to use this exhaust. If what I'm supposing is true, you could fix the problem by reducing further after your long bend after the collector (Tiger from A1 sells a nice long reducer). How far down you neck it depends a lot on how much power the engine makes and how long the pipe is.

 

If it had a standard collector, the opening would be pretty small, and it wouldn't be a big deal how big the pipe was going into the muffler. As it stands, it is.

Stan, I think you're spot on.

I've thought about going with an exhaust system from Tiger, but I didn't want the cash outlay.  I may have to pay the bucks and buy a 'proper' system.  In the end, it may be cheaper than having my mechanic fabricate an inline muffler system, and I'm not crazy about reducers.

 

Another 'point' to push me over the decision ledge, is that I've whacked my merged header pipe twice while traversing uneven pavement at illegal speeds.  I'm not sure how many more hits it can take.

Having said that, the second thing to hit is my big sump.  If I take away the merged header the sump will be number one on the 'whack-o-meter'.

 

Does Tiger have a website or phone number?

Stan with 1.5 inch headers what size tubing after the collector should be on it?  

Ron, In the military our radio jeeps has an inflexible steel skid plate protecting the sump from careless wackos like me

I just dont want my exhaust to sound like this.

 

http://www.youtube.com/watch?v=r52Jsm_qrSs

I think that engine backfired out of the wrong end.