megan headers?

[GReddySetGO]

I think he's talking about heat wrap. And yes, heat wrap was used, but only after the pipe had broken the first time.

Which brings me to another thing I forgot to mention earlier. The Megan Racing resonators used have this horrible metal on metal rattling sound. Sounds like a bunch of metal BB's inside a metal can. The exhaust wrap was use to help supress this sound.

[ruffrydasean]

/sigh.. $2k for the Full JP setup or this...

[TRD MCV20L]

Looks like its gonna be trial and error. I honestly wouldn't jump on the first batch that comes out. Thanks GReddySetGO for giving us the heads up on Megan products. I rather find out now than later on down the road when it'll cost me more later.

[SleeperSolara]

/sigh.. $2k for the Full JP setup or this...

I thought it was like $1400 for that setup????
How much was it for the headers and Y-pipe from JP????

[Ian]

/sigh.. $2k for the Full JP setup or this...

I feel the same way. Good grief.

[blakey2007]

hey i just got on this site and was wondering if those headers are able to be shipped and how much they cost

[SleeperSolara]

hey i just got on this site and was wondering if those headers are able to be shipped and how much they cost

Nope not done yet that i know of..........
And cost wise on the wallet; i think about $600 somethin' or around that.

[blakey2007]

thanks i was looking at those headers and y pipe on jp and that is ungodly expensive

[PhreakdOut]

I think he's talking about heat wrap. And yes, heat wrap was used, but only after the pipe had broken the first time.

Which brings me to another thing I forgot to mention earlier. The Megan Racing resonators used have this horrible metal on metal rattling sound. Sounds like a bunch of metal BB's inside a metal can. The exhaust wrap was use to help supress this sound.

Two things can cause the metal on metal sound.

1) Weld spatter loose in a resonator can without glasswool. Easy to fix in manufacturing.

2) Differental of thermal expansion which will cause fatigue of the innerpipe. In a case of a resonator, the shell and the innerpipe expand at different rates. The thinner inner pipe with its perforations will expand quicker as it comes to temperature first. The can, cooled by ambient air flow and its larger diameter expands slowly. The key to a good resonator design is to build in a slip joint on the innerpipe. A two piece innerpipe with a wiremesh pad between the two allows the pipe thermal growth and contraction during cooling. Welding the innerpipe on both ends will most likely cause a fatigue and crack between the perforations of the inner pipe. The end result, a rattle noise from the resonator. The first signs of this pending doom is a pinging or heavy ticking noise on cooldown.


(Anyone care to guess what I do for a living?)

BTW: Exhaust wrap is fine except for daily use. In other words, rain / moisture soaks the wrap and keeps it up against the pipe fulltime. Corrosion is what shortens the life of the part. Not the wrap itself.

If you feel you must use it, I'd save it for track days at the drag strip and take it off for the daily use.

[PhreakdOut]

Just a couple of suggestions for Megan:

1) Do a weld cut check to verify penetration of the weld.

2) Investigate the weld wire used.

3) How long was it before this failed? Look into doing a thermal cycle test. We do this on the OE exhaust before production. Using an engine or propane exhaust gas generator, ramp up to a set temperature for 5 minutes then down to a min temp for five minutes. (With a transition between the two taking around 5 minutes.) This is a test we run around the clock for 1.5-2 weeks. (We use automated test equipment and blowers to help the cooling) You can find some contract houses in the Detroit area who will do this kind of testing. Lotus Engineering (yes, the same company who makes the cars) in Ann Arbor, MI will run thermal cycle tests.

4) Look at the design of the collector. Ideally, each runner coming down has a straight section going into the collector. (This keeps expansion from being multidirectional.) The end of each runner is pressed into a cross sectional shape that will resemble one third of a pie. The three pieces of the pie are put together to make a round joint. (Welding the legs together lengthwise in sections and then at the end of the joint. ) The collector be sized to go over the three pipes joined together and 360° weld the collector over the three legs. It's all a bit more work but helps fatigue.

Feel free to have them email me with questions and I can discuss with our Advanced Engineering / FEA group.

[PhreakdOut]

One last idea ...

Adding a brace may help, but use this as a last resort. One, it adds cost. Two, sometimes it just transfers the problem to another area of the part.

Study the upstream parts to see is there is a lot of stress being placed on the headers. It may ba as simple as the angle fitup with the mating part. (The header supporting the load of the the exhaust.) Custom exhaust behind the header may have eliminated the flex sectio, used the wrong OD flex (or positioned it in the wrong spot.)

In my opinion, the headers are looking pretty good so far. Just a few design changes will really help it step up in quality.


Do I get a free pair of red Megan Racing seats for my consulting fees?

[SleeperSolara]

^^^^
Man you have it down like no other.
You job seems so fun.

[GReddySetGO]

^^ Contact Megan Racing with your suggestions, not me Maybe they'll give you something free

As far as the rattling/BB sound I was talking about. This happens with the pipe even off the car, cold, not only when the car is running. It sounds exactly like a bunch of metal BB's inside a metal can, being shaken up. Almost like sand.

Also, if any of you still want to buy these Megan Racing headers, etc. I am a dealer, so I can sell you a set once they are availible. Just be sure to see my opinons and past experience on them. Ultimately, its your car, your money and your decision to make.

[PhreakdOut]

^^ Contact Megan Racing with your suggestions, not me Maybe they'll give you something free

As far as the rattling/BB sound I was talking about. This happens with the pipe even off the car, cold, not only when the car is running. It sounds exactly like a bunch of metal BB's inside a metal can, being shaken up. Almost like sand.

Is there anyone already working with Megan on these headers? I'd be glad to stop by and visit them the next time I'm out that way.

Noise: Yup! It's gotta be weld spatter. There's probably an ugly weld somewhere on that can. I'm suprised the resonance can is empty. Thus it's a gas expansion chamber. Most would use SUS304 stainless wool to fill the chamber and take out high frequencies. (You wouldn't hear spatter rattles if the chamber were full.)

[dominoSLEV6]

Phreakd, I think each and every one of us would love to have you talk to megan about these. I know after seeing some of the 350z pipe pictures I'm a little skeptical about them, however I never have nor wil I ever have a doubt in my mind about you being the man on exhaust system knowledge. I would by any exhaust built with you on the design team sight unseen if need be. I'll try and hunt down some contact info on them and see if I can hook them up with some of your suggestions. I don't know where they're located but I think I speak for everyone on this forum when I say if you checked out their operations in person and contributed your $.02 to them and approved of their final product that it would seal the deal on selling the product to any of us interested on here.

It really is nice to see someone who isn't just repeating information they've heard, but rather KNOWS what they're talking about. And I think that can only be said of a select few in any given field or special division of a bigger total concept.

-chris