Jimmy325i

Since my moroso spiral flow has lasted shorter than my rear tires (under 5K miles) I'm getting an edelbrock rpm for the front muffler.

I searched and found that people claim they only last a couple years up front of the axles but I'm wondering if anyone has other experiences with them?

Do I weld this one in or clamp it for quick-changeability when it gets replaced under warranty?

swoop

Clamp it in. What kind of packing does it have?

Jimmy325i

Fully welded 409 stainless construction with stainless and ceramic packing rated at 1800 degrees F. This will be located approximately 18" from the collector of my header.

sirgrantalot

how do those sound as opposed to the mufflers right at the bumper
like the bonez stuff and stuff

and stuff

Jimmy325i

Some other people on here are running them but no one had anything to say about the sound. I'll still be running a tip muffler so this should just act like a presilencer only with lifetime warranty and half the cost.

Jimmy325i

.... and no life expectancy. Made the mistake of welding it in and one highway run later the sucker is ballooned and purple/blue/orange rainbow in the middle. (started life as stainless grey/silver)

Don't use these in front of your rear axle. It won't hold up.

mazdaspeed7

Lol... Justins first one lasted almost 3 days in a similar spot to yours. His second one has lasted that long already.

It sounds great. Its loud, but very nice sounding below 4K. Above that, its a little blatty, but i have still never heard a better sounding exhaust on a n/a.

J Oliver

Try Magnaflow stainless pre-silencer. I have it on my turbo 1st gen, still keepin things quiet at
33,578KM and has only turned a brassy bronze. I dont know maybe NA's run hotter than TII's.

mazdaspeed7

n/a's have very strong exhaust pluses, which abuse anything other than a straight through muffler. Turbos tend to break up the exhaust pulses, so they are nicer to mufflers. Thats why turbos sound better too.

Jimmy325i

I know we've been talking about this in another recent thread. Just thought I'd follow up on this one for people searching thread titles.

If I send Edelbrock a pic of my muffler think they'll send me a heavy duty version under warranty? I tried buying one off the bat but no one stocks the *******... I couldn't live with my moroso rattling for 3 more weeks to wait for them to send me one.

I was back under the car today and saw that the center of the muffler has turned **** brown as well as both the inlet and outlets. (still has the rainbow heat coloring on either ends of the middle of the body of it)

Total mileage on this muffler is 300 hwy and about 60 city. Pile of ****...

J Oliver

Hey I got an idea why don't you go turbo! That will quiet things down.

Bambam7

I have a pair of those as my main mufflers... they are OK. They actually sound pretty damn good when there is a cat or pre-silencer in front of them. They don't have a super deep sound like some other huge cans (like the Greddy or RB), but it's nice and smooth.
I love the way my car sounds now though- a borla xr-1 as a presilencer, and the edelbrock main, coupled with 2 resonated tips. It sounds even smoother now that the turbo is on!

Bambam7

Oh, and a spiralflow NEVER belongs on a rotary.... You will notice a nice gain in power without it. They really kill pulse velocity, and therefore reduce the scavenging effect that is so crucial to rotary power.

Jimmy325i

Ummm... I loved the spiral flow. till it blew up. Had no ill effects and it makes its power by stacking soundwaves not killing pulse velocity. I'm too tired (and mostly lazy) to actually calculate how many pulses have occurred before the collected exhaust actually exits the header let alone the THOUSANDS which happen by the time that same pulse hits my first muffler. Everytime your exhaust bends it changes the velocity of part of the pressure wave.

What would be bad is if there was a reflected wave or a production of a standing wave which could travel back up the exhaust and disrupt the oncoming pulses. I think the design of this Edelbrock RPM muffler actually creates these in certain rpm ranges as I can feel a difference in power (weak spots not quite like a stumble) over my midrange with this system. (technically my 4th new exhaust on the car)

Jimmy325i

Here she is after 500 miles...

The crispier side is what was towards the motor.



Backlighting for the internal shot is poor. It's completely gutted of any packing on the side that was aimed up.

Capn' Wankel

Wow Jimmy your muffler looks wonderful compared to the rpm I jsut took off of my 88 GTU with Racing beat header. As stated in the side exit exhaust thread I blew a hole 2 inches by 4 inches in the top of it and then the muffler shredded itself apart. It looked as though the muffler commited suicide by sticking a shotgun in its mouth and pulling the trigger. Absolutely terrible muffler.

As far as exhaust tone and sound is considered though I agree that it has the nicest smoothest sound that I have heard on a rotory yet. (For the 2 weeks that it lasted anyway)

I TOO disagree about the moroso spiral baffled muffler. I haven't done any complicated flow testing and pulse testing with the muffler but it absolutely ran wonderfully and made hella power on my 88 GTU. It sounded great albeit a little bit louder than typical packed mufflers. And as far as power....when I hit 4.5k rpm and my wired ports started coming in to their own I hauled serious *** (For an NA) all the way up until 8k+ rpm. It was wonderful.

-Lee

PS- After writing this post I find that I am in love with the moroso spiral baffled muffler. Maybe we should all give Moroso a call and see what they can do to strengthen the welds in their line of spiral baffled mufflers for the sake of rotory enthusiasts. I mean they have already received 3 blown moroso's from JEGS where I got them from (I sent them back for full refund after the 3rd gave way.).

PSS- For anyone in the future that searches for exhaust and comes across this thread.... DO NOT GET THE MOROSO SPIRAL BAFFLED MUFFLER FOR YOUR RX7 AND DO NOT GET THE RPM MUFFLER FROM EDELBROCK! YOU WILL LAST TWO WEEKS AT MOST!

BATMAN

****!

I didn't want to hear that.

I was actually looking at these 2 mufflers for my FD.

dammit!

1987RX7guy

iTrader: (3)

holy grape fruit shooting rice cannons BATMAN what are you doing in here@?!?@!




Why not use RB for the mobile?


Santiago

BATMAN

I did.

Got bored with the dual tip and went with the www.powertone.com tips.

They sound great.

But when I start up the car in the morning the neighbors give me grief about the decibels.

One have threatened to call the cops.

Once the car is warmed up it's a little better.

BATMAN

I have 5k miles on my FD with the Edelbrock RPM (now packed with ceramic wool that can take 1800F) and have ZERO problems.

Most people will agree that this is the best sounding muffler for the RX7.

It just makes it sound deeper and more exotic.

yea .... yea... this ain't a FD section, but no one in the FD section has any experience that I could find on the Moroso/Edelbrock mufflers.

I plan on getting a Moroso and clamping it on my other MP.

This way I will be able to compare sounds and power.