build your own !

[jevvy]

Project looks great, good luck.

I think thats the same box timmins uses on his happy crab muffler

I ran one for a while on my car and it gave great power and a great sound - a friend used it when his Vram was remapped and he got 326 bhp running the magnaflow x over pipe thingy on an otherwise standard engine.

[Darryl Irvine]

any ideas on where to put the Ox sensor? I think the lead is long enough to go anywhere. Do you think The Magnaflow X" is acceptable? Thanks for the comments so far.

[TimT]

any ideas on where to put the Ox sensor?

Weld a bung at the end of the collector, assure that is at least 20 deg above horizontal. You can install O2 sensors in each bank, I think that is unnecessary, unless you have carbs or are a data collection freak..

[Darryl Irvine]

Thanks for the info Tim.

[Darryl Irvine]

Started the other side today. I am alittle concerned that i did'nt move the merge collector forward by 2 3/8" but instead elongated all the primaries. Any thoughts? I have not welded anything up yet, so I am open for suggestions. Thanks.

[911st]

Just my two cents:

Having two different primary tube lengths might broaden your power band a little bit. However, as you have a very low overlap cam there really is not any exhaust savaging going on so it will probably not be of any difference. Your largest benefit being to orderly exit of exhaust on each side. However, this might make for more of a trafic jam at your your secondary cross over point.

I still am not a fan of using the X muffler. Exhaust will be coming directly at each other from each side end of the muffler. Would much rather see a Flow master or something like this.



Or this with one side passing through the bottom and one on the top.





The best.

[Darryl Irvine]

Thanks 911st for the info, maybe someone would want my brand new magnaflow for a discount?? Well onto fabbing the flanges!!!

[JeremyD]

I blew 280 hp with my Magnaflow muffler with no restrictions (part # 14386)



have since changed over to 993 headers and an MK exhaust. The Magnaflow is a little loud. You know it's loud when your 10 year old son complains that it's too loud!

[jcge]

Darryl - just noticed the orientation of the 3:1 merge collector - rotating it 60 degrees would put 2 of the pipes "flat" facing the ground, with the third pipe on top. Don't know if this is useful to you re underbody clearance etc.

[Darryl Irvine]

jcge,
Yes I thought of that too, but it became too difficult to route things that way & get equal lenght-Probably just me just not seeing things right? I must of tried 20 different iterations before I settled on this one. I may have to raise my car however, it's pretty low.

[Darryl Irvine]

Finally got some time to weld ! Well, not the best looking welds but I think they hold-This was my first real attempt at TIG welding. Anyway, any comments on the proximity of the lower tube to the valve cover ?? I am concerned I messed up I only have about 1" to 1 1/4" clearance at this closest point. Thanks

[dan79brooklyn]

I'm always amazed by the beauty and design of the 911 engine, not too mention power and sound.
It's a great project you've taken on, I hope you're having fun!

[Darryl Irvine]

Thanks for the encouragement Dan ! It sure has been one hell of a learning curve!