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So after switching from GIAC to COBB Stage 2 I decided to go all out and get the full Stage 3 upgrade with y-pipe, decat, equal length mani's, plenum, Forge diverters and By Design intercoolers. Intrepid you say? Well, I did the install myself too... I am both a FAA licensed A&P mechanic and electrical engineer so I really only trust myself to work on this particular mach generator.
I am currently organizing some photos from the three day long thrash and I'm hoping to offer some good intel for any fellow warriors who dare attempt this transformation. With some guidance, determination and having the right stuff ready before you start it can certainly be done in a weekend. I spent a lot of time hunting down hardware because I'm super retentive about torquing to spec and the equal length manifolds made some of the bolts impossible to reach with a torque wrench. I came up with a rather ingenious solution. More to follow.
First a teaser review of the Kline equal length manifolds. For those of you who don't know, I sacrificed my brand new car at the altar of creating these things. Yes, you all owe me big time . Upon bringing my brand new baby home last February I put her on the lift, stripped off the stock manifolds and mailed them to Felix Kline in Romania so that he could create the jigs and do the development on the 991 parts. After waiting several months the first ever set arrived at my door. A trial fitting revealed some clearance issues so I documented it carefully and coordinated with Felix so that his jigs could be modified appropriately. A few more months later and a lucky few of us have these beautiful pieces on our cars. Some side by side shots:
Absolutely gorgeous equal length! One of a kind.
Stainless steel spaghetti!
In exchange for my help (and enduring patience) Felix threw in a free set of decat pipes and express mailed everything from halfway around the world. It was definitely worth the wait! I already had the 2.5 inch system with 100 cell cats but I wanted more volume. The decat and manifolds certainly did the trick. I was skeptical when Sam said there would be no drone but he was absolutely right. There is NO DRONE. What you get instead from the decat is a nice increase in volume but only under load. It's a real pussycat when cruising.
The manifolds are the real centerpiece though. Much in the way that a bugle sounds different than a french horn, the equal length manifolds really change the sound of the car and it's all about the tubing. The muffler tweaks the volume but the manifolds really give it a different voice. A good friend of mine was nice enough to mail me a stereo field recorder and I'm trying to get it to work with my DSLR camera to take some sweet vids. Keep checking back for updates.
I will continue reviewing the components over the course of a few days but first a few words about Sam. Once I decided to do the stage 3 we were on a bit of a time crunch and to add to the challenge, Sam didn't have any y-pipes or diverters in stock. In an overwhelming show of force he teamed up with Tom from Champion who FedEx'd me the y-pipe from his own stock! Only two serious enthusiasts could get that done. Then Sam coordinated with Forge to get the diverters sent directly to my house. The coolest part of all this? He did it while on the road to SEMA. No bullsh!t.
When I returned from training my parts were all waiting in the garage having arrived from several different corners of the map. That's customer service, folks.
My overall impression of the result is that the power is surreal. I have been full stage 3 for a week and finally opened it up today. I just... you can't believe the sound that comes out of the back. And the speed is completely insane too. Stay tuned!
- Patrick
Last edited by PMNewton; Nov 23, 2015 at 09:32 PM.
Congrats Patrick and thanks for the R&D as I directly benefited in having my new equal length headers fit puuurfectly.
Im glad it all was worth the wait for you and yes a few of the header bolts required some outside of the box thinking. A small price to pay for an equal length package of beauty sandwiched within the factory header space. The end result is a system that is perfectly balanced for the street and a screaming monstrosity at the track. The proven performance gain is a freebie.
My experience in moving boxer motors form unequal to equal-length headers/manifolds is that there is a significant difference in the type of sound.
That "boxer rumble" everyone knows is (in my experience) primarily from the unequal length manifolds. The sound changes to much more of a "inline" sound when equal length manifolds are added.
It also might be worth looking into that it changes the breathing of a couple cylinders a bit, and you may now need a retune in order to make sure you aren't leaning out or richening a couple of them. I have no evidence that this happens on a Porsche, but certainly did on high-HP Subaru motors after equal length manifolds were added.
There was quite a bit of power and spool to be found when we used to go equal-length, but it was slightly more complicated than just swapping the headers.
Sounds like Sam really did some great things for you. He sounds like a businessman who knows that the best investment is in his customers
Cheers. I always try and thank the team effort and in this case it even includes the client Patrick! Can't wait for your full review P.
Yes when we started by adding the manifolds we had the most powerful 991TT on the Cobb dyno and then tuned from there. It has been great and Felix/Christian from Kline are amazing at this game. True innovation and engineering at work. They can weld too ; ). Put that together with the rest and you have an A+ set up. I do my best to follow through and support all of my guys from A-Z.
. Upon bringing my brand new baby home last February I put her on the lift, stripped off the stock manifolds and mailed them to Felix Kline in Romania so that he could create the jigs and do the development on the 991 parts. After waiting several months the first ever set arrived at my door. A trial fitting revealed some clearance issues so I documented it carefully and coordinated with Felix so that his jigs could be modified appropriately. A few more months later and a lucky few of us have these beautiful pieces on our cars. Some side by side shots:
