yellow 72

There's a difference between a great sounding exhaust and flat obnoxious....which imo is what open headers on the street is.

vintage-racer

I'm leaning more towards the Max flows part #21046HKR,hoping they will create the right kind of NOISE.. The inserts I had on my 68 small block were a straight thru design,with a perforated tube inside ,looking unobstructed end to end . I loved them. I'm hoping that the Max flows are the same.

yellow 72

I had 2 1/4" perforated core Dynomax Magnum glasspacks in mine before I replaced them with the Max Flo. They have the same deep tone as the Dynomax which I prefer.

vintage-racer

Can you see (2.5")straight thru the max flows from one end to the other?

Frank_833

I let mine idle for 10 minutes on the driveway before the cop showed up. That and I live on 3 acres!

But I have one neighbor who complains when my son rides is '69 Z50 Mini-Bike in the yard.

2000FRCZ19

yes, they are open from one end to the other with no obstructions. it is a straight 2.5" hole surrounded by a perforated glass pack.

GrandSportC3

Well, Florida is different.. I even lived for 4 years in Miami Beach in a Beachfront condo with the car in the condo garage.. Everytime I came home or left the building (in building parking), all the car alarms went off. Never got any complaint.. In all those 40k miles, I got ONE warning by a cop in Miami Beach

I'm at a red light at LINCOLN AVE and COLLINS AVE in Miami Beach with the car idling (probably at about 110 db:

Cop walks over to my car:

COP: "You got to do something about that exhaust!!"
ME: "What's wrong with it? "
COP: It's too loud!!"
ME: "How loud may it be?"
COP: "I don't know but it's too loud!"

Only got a oral warning, nothing on paper..

Other than that, I only had the cops called on my once when I fired my car up in the afternoon to set the timing. Cop came and I told him that I was just working on my car and he told the neighbors that there's nothing that he can do as long as I don't do it during noise ordinance hours..

Gotta love living in Florida!!

GrandSportC3

It really isn't that bad.. I usually drove close to IDLE RPM in residential areas and only opened it up on the highway.. With the overdrive (had a .68 overdrive in the TKO that I used to have in the car) the noise level at cruising speed wasn't bad at all.. Neither was it bad at idle.. Just when stepping on it, it felt like a atomic bomb just exploded..

yellow 72

Yep, it's just a straight 2 1/2" perforated tube end to end

DEVINSVETTE

the testing is in I calculated about a 100 h-p loss using the muffler inserts that a friend had for the fun of it from hooker, compared to the augers I had made for me. putting the car on the dyno proved it. the bet was one it was rite at 98 h-p loss using the hooker mufler inserts. these inserts keep in mind also limited engine rpm figure that what a plug those mufflers are this story came up again from about 32 years ago when a friend was building a motor for a 69 vette that was owned by a customer, the motor was dynoed at 650 h-p but when it was installed we said no way something is wrong even as excited as the customer was he took the vette home but soon returned and said you got to kidding me there is no way this is 650 h-p after checking the tune up we pulled the mufflers out, me and my friend went for a ride thats the first time my head hit the rear window, later that summer the customer returned and had us pull the motor and install a 350 he said it was just to much for him I say ***** but 650 h-p isnt nothing to laugh at , regardless my vett had a zz502 with the side pipes and had augers made for it the difference was so much as calculated and we all know how much a 100 h-p COST I cant remember the name of the muffler shop in Hayward cal but it was on A street they were cheap and the sound was perfect but you must plug the inner tube with a freeze plug to force all of the exaust threw the auger not threw the tube no welding required as for STS parts more junk dont do it......

bluzman2004

I just installed the Hooker Maxflo's after reading through all the posts on this forum. They sound great! A more bassy exhaust note than something like a Flowmaster or other chamber type muffler. I didn't notice any loss that I can feel in the seat of the pants. This isn't the most accurate test of course, but I'm running a 434sbc so it needs to breath. They are louder than the old Reverse flow mufflers that came with my sidepipes 15 years ago. I would recommend them.

63mako

The Maxflo's were released a couple years ago. No HP loss vs open headers even on a 600HP big block. The older reverse flow and glasspack Hooker had until the Maxflo was released would knock your power down and I would guess 100 HP on a 5-600 HP car is probably about right. They were horrible, but not the Maxflo

69ttop502

I have not tested the Max Flow specifically, but I have tested a 2.5 inch straight through perforated core muffler (Loback) on my 614 horse 502, and in my educated opinion backed by observation, there is no way a 2.5 inch muffler will not pose a restriction on a similar motor. Even a 3 inch dynomax bullet showed a restriction. The STS baffles uncapped and cut did as well, but showed less than the others. Someone once calculated the open area of the baffles, and I can't remember the number, but it was way more than 3 inches. I will not get into the opinion of sound, although the STS baffles sound great on mine, but if you want horsepower, they are the best way to go from my experience watching both engine and chassis dyno tests.

Oh and in one of the tests, I saw the reverse flows and glasspacks from Hooker lose 90+ horsepower at the tires on my 502 when it was only a 350 rwhp motor.

And to the poster calling the STS baffles junk, get a clue. Tell us all why they are junk. They may not be cheap, and everyone may not like the sound on their motor, but they do what he says they do.

Frank_833

Have them ...and...

63mako

Our search function is horrible on this forum. I read a thread last fall in C3 tech and Performance. They did dyno testing @ Carlisle. The strongest motor tested did back to back tests with open hooker sidepipes vs sidepipes with max flows. The difference was a couple peak HP on a 600 HP big block with better low and midrange with the max flows. If anybody can find this thread please link.

69ttop502

I remember the forum member with the 565 in a 71, I think it was ZL1 POWER or something like that found the same. I certainly am not arguing those results, I just did not see the same.

I am also still waiting to hear why the baffles are junk. Substantiate that statement Devinsvette. Hopefully if you do you will find the shift key on your keyboard, and maybe use a comma or two. Spellcheck is also your friend.

yellow 72

I'm with 'ya.
Better yet lets organize a search party to hunt down and punish this disbeliever who dare utter such blasphemy!

0Road-Race Vette

Jay-Dog

Anyone know the price and source for Hooker Max-Flo's? How about prices on other varieties?

69ttop502

I was waiting for you to rejoin the thread my old pal Yellow72. I don't think even you would make such a remark about a product in such a manner. Maybe I am wrong:


The nice thing about the Max Flows is, according to the Holley website, they produce 23 percent more horsepower than open pipe. Wow, I guess it is only just a matter of time before every drag race machine and race car will be running Max flows. I certainly think the max flows sound great as well. Hell, I thought the glasspacks sounded great too. But 23 percent more average power than open pipe. C'mon, and I do know the difference between average and peak.