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RPi Headers/Exhaust Manifold: Get Smog?

30K views 156 replies 29 participants last post by  keang24 
#1 ·
After several months of testing, we have came to the conclusion that the factory headers were extremely efficient for bottom, midrange and top end power. The main restriction was from the primary cat. Deleting the primary cat would yield significant gains. Some aftermarket headers show good gains on the top end while compromising low end performance. Our headers solution will allow the use of the factory equal length style tubing, while our cat delete will improve hp through out the power band.

Need to smog? Dont pay someone to remove your aftermarket or modified factory header (15+ hours of labor) just to smog your car. Simple unbolt our v-band clamp, put on your stock cat and drive it to your local smog station.

We are working on a solution for the CEL to NOT turn on while our race pipe is installed. This will require NO ecu reflashes. Yes, NO, nada.

$4299, Header package includes:

- modified header
- RPi race pipe (eliminates the cat)
- modified factory cat (complete bolt on when race pipe is unbolted)

 
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#2 ·
Cool Eloy, told you I was waiting patiently for you to post this!!

This is pretty much the same thing Turner is doing right?
 
#4 ·
Cool Eloy, told you I was waiting patiently for you to post this!!

This is pretty much the same thing Turner is doing right?
No, it's a bit different. That one comes with the stock cat removed and a straight pipe welded permanently on to the headers. Our one comes with a v-band clamp so you can bolt or unbolt the stock cat or straight pipe very VERY quickly.

In other words, once this system is installed, if you want to bolt the cat back on, you lift the car, take off the bottom shield, unbolt the straight pipe, bolt on the cat, replace the bottom shield, and lower the car back to the ground. That's pretty much it. Very fast procedure. :)
 
#8 ·
So, would I need to ship you my factory headers or do you have these ready to go?

Secondly, will there be a core discount if I trade my factory headers?
We have a few in stock and there will be a core charge if your headers are not shipped to us. We are still working out a few details which may affect the price. The price may or may not come down. I will keep you all updated.
 
#6 ·
I love you guys at RPI... Very very very Long time :)
 
#10 ·
Eloy, a few questions:

  1. I choose to keep the Cats, will this work with the Dinan SW? Will we need to relocate the O2 sensor?
  2. Will this work with Supersprint X pipes (and mufflers)
  3. What are the gains?
Thanks.
 
#11 ·
Sorry to bombard, but I also have a Q...

Can you quantify the benefit of removing this cat versus the secondary cat?

I understand this will be better because the gasses are hotter and more voluminous closer to the heads, but in RWHP - delete primary cat versus delete secondary cat - what's the difference?

Gracias chicos.
 
#12 ·
We've never tested the headers with the Dinan SW so I cant tell you exactly how it will perform. The header package will include EVERYTHING you need to bolt on to your engine. You wont need to weld bungs or make your own o2 connections. The headers will install like stock so any aftermarket section 1s that bolt on to your stock headers will work fine.
The primary and secondary cats are really different so comparing the two for performance is kinda tough. We have not seen any significant gains by removing the secondary cats though. We will be posting dyno sheets soon.
 
#18 · (Edited)
Very cool and innovative idea. I like it a lot.

Also, how is it possible to elimiate the CEL without software?

The DME is camparing the voltages on the o2 sensors before cat and after cat, and based on the difference between the two, it throws a light or doesn't. Are you talking about using o2 simulators or something like that?

PS: On a side note, will the RPI M5 pulley work on my 08 M3? Same engine, different crank and two less pistons. Maybe it's the same thing??
 
#22 ·
Eloy, you dont' have to be hurry because Rab Dog still in "Far East" :haha::haha::haha:. Rob, get your @$$ back here if you want to see the dyno sheet with your own eyes:hihi::hihi:

I'm sure Eloy will give a good assessment since he has installed/dyno'd both SS and Evo, Mr.Slagger:blink:
 
#23 ·
It will be about a week to two weeks before we do an official dyno run with the headers. There is no doubt about the gains we will see (looking for 15-20whp) as we have seen similar gains with a welded test pipe on stock headers. We just wanted to offer you guys a "bolt-on" solution.

Mike, its possible to not have the CEL even running without a cat. We have the GT Race and GT downpipe for the Opel GT. Our GT Race does NOT have a cat, while our GT does have a high flow cat. Neigther downpipe will throw the check engine light. If we get it to work, youll see how we do it :) Its really about testing the product.

Rab Dog, do you have kenny's posts blocked? Most of us do. Its almost like listening to my wife talk. I hear it, but most of the time, Im probably not listening. We'll probably have a dyno day here and it will give us a chance to show you the headers in person and show you how it works, etc. I know "other" companies are having problems with parts fitting or not performing as advertised. We try to prevent this by doing a BUTT load (ok, M5baller make a comment) of r&d and by making everything locally here in the states (all RPi products are made in house or fabricated locally).
 
#28 ·
Ha, when u were a monk you missed alot going on... the exhaust is back to stock on his car!
 
#36 ·
So for what is essentially the same price as a set of ceramic coated headers from EVO you guys are selling STOCK headers (that we supply) that you cut the end off and weld on a car plus a cat delete pipe? And you guys are EXCITED about that? Am I the only one offended by the price here? Can someone explain why this should command the same $$ as a full set of headers? Am I wrong?
 
#37 ·
Of course you are entitled to your opinion. Not everyone wants to pay for a properly R&D'd product. We offer a modified stock cat, header and race pipe that has been tested rigorously. The price of the jigs, flanges, material and months of work/tests is what the price reflects. Sure, you can get a set of headers at a cheaper price. In fact, we have a set here that has not been sold, although we have tried. They are ceramic coated and anyone can come pick them up for $3k.
 
#40 ·
Eloy looks like a good product. Looking forward to the dyno results. Btw, the crimps in the stock headers must be for a reason. I mean the M department did not do that to purposely make the headers have less power. They did it either for the purpose of maximizing EGV or fitament or another purpose I am not aware of. Bottom line is that they are equal length and as such they want to manage flow to maximize for the headers being equal length. What is your call on this Eloy?
 
#41 ·
You know we have been working/testing this project for some time. The bottom line is that the stock headers are pretty bitchin. It would cost a LOT to build a header like the stock one. We'll have dyno number soon as we want to make sure the flanges and materials we use are up to the task. Havent talked to you in a while. How is your car running?
 
#42 ·
You know, RPI is suggesting that Header gains come from the primary cat delete. Even if they were the same as a complete header solution, this will really great due to the fact that the whole smog issue can be reversed w/o much labor costs.

I don't mind forking over the $$ for a better mousetrap, especially if it is OEM, produces the same gains and reversible... even if it involves less materials (vs complete headers). To me, that's just like paying for software upgrades... there are no parts... you are paying for R&D.

All things being equal (~same hp), the less aftermarket stuff and the more OEM stuff the better. Awaiting the dyno results...
 
#45 ·
I doubt that a secondary cat only will pass a sniffer test. I believe
the primary cat is a 2-way cat (not sure which two emissions it's
cleaning up) while the rear is a 1-way.

If you don't get software or a rewire of your rear O2 you'll definitely
get a CEL. Even with software it sounds like there's still an internal
error that emissions testing will find. Darren_dallas went though
this and had to rewire his O2 to pass. He didn't have to do a sniffer
test which unfortunately we in CA need to do.
 
#50 · (Edited)
Love the concept! This is exactly the kind of simple ingenuity needed. The sole reason I dont have headers is due to smog worries. I would buy these over other headers even if they made less power. The price does seem a little high but it is too early to judge.

When are they going to be available?
 
#51 ·
Believe it or not, this is a serious post on this issue!ouich

Remember, this IS the stock header with a modification to bolt on and off the primary cats for smog station testing. I think this is a great idea!:M5thumbs: I do have questions and have yet to see it posted in terms of ECU adaptation and CEL monitoring.

Before that though. I need to make this statement from my understanding; these are not going to be these pretty polished and shinny chrome thingys that we see with the other aftermarket headers. I may be wrong, but that is the reason for the core charge. They will take car 'B's headers and modify them to sell to car 'C' and so on. I guess the question arises, what came first the header or the modified header? Eloy, you can answer that one.

The beauty in this concept is the acknowledgment that the original header design is pretty trick in terms of performance. It's the emissions components that are strangling the potential. So, when one looks at various aftermarket headers, is it the headers that are providing the performance gain, or the deletions of the cats that is giving the gain? RPI believes it is "Primarily" the deletion of the cats. I think they are right from what I have read and with my detailed discussions with Eloy at RPI.

So my techie question. How have you resolved the CEL situation. How does the ECU react to A/F ratio when these sudden changes occur in the exhaust make-up. How have or was that tested? :dunno:

As for cost, there has been much discussed. I believe it may boil down in some minds that they are not getting what they are used to from other manufactures in the market that is bigger than the E60 M5 (or M6). Something new, polished, and subliminally suggesting, something different! :confused:

Thank Dinan for proving that there is very little to do to improve the E60 in terms of optimum performance. See other threads for multiple discussions.

Falb stated it succinctly, simple ingenuity. Some do not see the value in that. Is $4,000 plus the right price? :dunno:

I will see what the ultimate numbers in gain are, wait to have my CEL questions answered and ultimately wait for the first round of "I gotta have it first" dudes and realize the reduced price product. Plus, I get all of the beta bugs resolved.
:cheers:
I got through that relatively well without smart a*s comments, nice! I am growing up!:hihi:
 
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