Moroso Spiral Flows = big restriction?
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From: Temple, TX
Moroso Spiral Flows = big restriction? My dyno numbers seem to be on the low side and I'm wondering if a shitty made H pipe along with Spiral Flow mufflers could cause a significant power loss?
I hear people all the time say how restrictive the Moroso Spiral Flows look. Does anyone have any true proof or knowledge about them?
I'll attach a photo of what they look like.
If anyone remembers the Car Chemistry inserts that were popular for awhile but were causing HUGE power loss on the dyno like 50RWHP loss could the Spiral Flow Mufflers be having the same affect?
I hear people all the time say how restrictive the Moroso Spiral Flows look. Does anyone have any true proof or knowledge about them?
I'll attach a photo of what they look like.
If anyone remembers the Car Chemistry inserts that were popular for awhile but were causing HUGE power loss on the dyno like 50RWHP loss could the Spiral Flow Mufflers be having the same affect?
They look restrictive as hell to my eyes! Those baffles inside look to be a real flow restriction. I added a 3" 2 disk Car Chemistry baffle inside my I pipe at one time and I lost 33rwhp @ 34rwtq over an open QTEC right before the baffle. The Moroso muffler doesn't look too far off the design of the CC Baffle.
My dyno with the CC Baffle overlaid with the open QTEC run
My dyno with the CC Baffle overlaid with the open QTEC run
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From: Albuquerque NM - The Land of 8000ft DA
What I do know is with the older C3 Vettes you can buy the side exhaust from Hooker. The exhaust comes with glass packs and several people have seen serious gains, on the order of 30-40+hp, when switching from glass packs to spiral flow exhuast setup. They sound better to.
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From: Orange Park/ Jacksonville, FL
I dont think the moroso is a real big restriction. I have one in the I-pipe in place of the resonator on my LM, and didnt really notice a change. Its still straight through in the middle, and it doesnt have all the baffles that it shows in the picture, mine only had 3.
just my $.02
just my $.02
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I ran 4 mufflers on my car. 2 race magnum bullets right after the headers, then 2 spiral flows after that. That back half with the spiral flows bolted on with two 3", 3 bolt flanges so I could run some quiet...er exhaust on the street, and unbolt them at the track. Every time I would unbolt the back half, same day same track, back to back runs, the car would gain 2 1/2-3mph with the spiral flows off the car. They sound decent and do a fairly good job at quieting things down, but the track doesnt lie. Take it for what its worth, thats just my experience.
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They are extremely restrictive. We have had this discussion before and people did not believe me when I said the car fell on its face after these mufflers were installed on my car (compared to bullets). Well here I am saying it again if you have them take them off if you are getting them they would make a ugly paper weight lol. Here is the thread I am referring to
https://ls1tech.com/forums/showthrea...+flow+mufflers
https://ls1tech.com/forums/showthrea...+flow+mufflers
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From: Orange Park/ Jacksonville, FL
I put my car on a dyno a couple of weeks ago and put down 312rwhp with the moroso(in hot humid FL. weather). Everyone said I should put down 320 with my mods (lid and LM w/o moroso), so I figure I lost between 6-8 hp. I'm going back in a few weeks after I install my headers to see whats up.
I can see how they can be a little restrictive. But the dyno numbers you are saying are ludicrous. They aren't THAT restrictive. If you are running 3" anyways, the mufflers will not likely reach there full capacity.
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Ok there is alot of aftermarket Y-pipes on the market that are 3" to the catback. None everytalks about having a big restriction on thier 400-450 rwhp car with a single 3" pipe (or single 3" cutout) to the catback.
Now if you have true dual 3" (Which is more than enough flow for almost ANY n/a ls1 setup) then youve got DOUBLE the flow. If each spiralflow is 3" thats ALOT of flow comparing to a single 3" that most y-pipes have.
The spiralflows would have to be like 50% restrictive to be a problem wouldnt you think??
Now if you have true dual 3" (Which is more than enough flow for almost ANY n/a ls1 setup) then youve got DOUBLE the flow. If each spiralflow is 3" thats ALOT of flow comparing to a single 3" that most y-pipes have.
The spiralflows would have to be like 50% restrictive to be a problem wouldnt you think??
C4VetteLS1.... I see what you are saying about having the better flow with the true duals. However the design of the spiral flows is still restrictive even though it may be a 3" muffler, take a look at the inside which is definately not 3" diameter. The small hole through the center looks to not be more than 1.5" in diameter and the baffles surrounding the hole would really hold up the exhaust gases from exiting the muffler quickly. On a true dual setup it probably would lose 5-10rwhp and not be as noticeable, however if you stuck one of those in a 3" I pipe I would imagine a 20-30 rwhp loss easily. My 3" CC baffle looked to be even more free flowing than the Spiral Flows but I lost 33rwhp @ 34rwtq with it also.
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From: Orange Park/ Jacksonville, FL
I seriously doubt theres a 20-30 rwhp loss with this thing. If so, that means that last week, I wouldve only put down 290 rwhp instead of 312rwhp like I said in the earlier post. I just cant see putting 342rwhp to the ground with just a lid and LM. Maybe you guys are right and they are a little more restirctive, but 20-30 seems like alot. as soon as my ORY comes in I'll put my headers on and go back to the dyno and see whats going on. If oyu guys are right and the #s are really low, then I'll dump it for something else or get a cutout
