Finally, BlackmagiCL_S, myself, (had a chance to install the Stone Headers on my CLS and now his OBX haeders on his CLS...and have before and after dynos.

Let me first start with the installation of Stone headers. The installation did not go smoothly as expected

Unfortunately, we run into drilled-holes/engine studs alignmet problems.

I was so .. The front header, rear header had it is holes so tightly drilled, and not 100% aligned to the studs. Using the Gaskets as template, you may think that the drilled holes are Ok.. But they are not. I had to use a circular file and bore out those holes.. It was a very tedious labor. I was finally able to fit the front and then the rear was also misaligned. They can fit 50% at an angle but they do not fit if they are parallel to the engine block. After some more filing, We were able to fit the rear header. Similarly, the A-pipe needed a minor filing at its flange to the Catalic Converter. By 4:00 PM ... We were done with my CLS!! :o


Now, as for the before and after dyno. I had 4 pulls. The first was garbage as it was in open-loop mode and my CLS was not warmed up.. We warmed up my CLS, disabled the VSA and did another pull. This second one was Okay. After the installation of the stone headers, we did 2 more pulls... Both were good. I gained some 4WHP and 4 lbft all across the rpm as shown in this graph.



As you see, I included 3 graphs, Acutal HP (Uncorrected):

1) The last September's best pull with OBX headers 221 WHP, (The green graph)
2) Today's, OBX Headers pull, (The red graph)
3) Today's, Stone Headers pull, (The blue graph)

Now, the condition were as shown on this graph. ( Note how Today Cold weather resulted in a Correction factor of 0.92-0.93) !!! this means that the CLS engine would would make some 8.7% more HP than the standard conditions!!



Finally, correcting to SAE we get:



Note:, Although the I made some 17WHP more than last summer dyno, correcting using a 0.92 factor would result to a lower SAE WHP then last time best pull...

However, as you can see, the stone headers still outperformed the OBX headers by 3-4 WHP, 3-4 lbft!

And here is the A/F graphs along the (Actual HP):




Finally, one more observation. I dynoed this time on my Winter tires. A closer look to the dyno runs showed that this time runs are underdriven (slower than the Nittos on which the last time I dynoed) by 1.6%. Effectively, cutting the HP and Torque numbers for the this time runs by 1.6%

Here is the Actual HP with the Final Gear ratio expressed in MPH/RPM:


OBX headers Dyno on BlackmagicCL_S's (Stock 03 CLS- Auto):

BlackmagicCL_S dynoed some 202 WHP (STD) and then with the OBX headers he pulled 220 WHP (STD). He gained some 18-20 WHP (STD).

N.B.: Thanks for Bulldog for showing up too. I snaped his mug shot Just in case...

 

good work!!! What other mods does BlackmagicCLS have?

 

CT springs and Sway bars!

 

nice info...how do these numbers (Approx.) compair to the "Solid Gold" Comptech Headers?

 

1killercls,
About the same in terms of performance........howeover, Comptech doesn't offer DiY kit with their headers When they say bolt-on..........they mean bolt-on.

 

Givin the choice..which would you buy?

 

I bought comptech before and I would really do it again. Their quality is top-notch. Price is high but if you look at other cars and the amount of money people pay for performance products it's about the same as the Comptech. Take a look at what our BMW breathern is paying for an intake, headers, flywheel. Unless you buy a domestic and have MOPAR, etc., you really aren't going to have many choices. That being said......if you can deal with non-CARB issues and perhaps quality like holes not being big enough then STONE seems to be the way to go.

SOOOOOOOOOO......i'd buy comptech. It might take longer for me to get them but in the end I know that Comptech is Comptech

 

Comptech RULES

 

Yea I think I will wait 4 the Comptech..I have CT Springs and Sways...

 

Just a reminder. Those headers were designed a prototype and I was test-fitting them!

 

good lets hope there is viable alternative.

 

Fitment should be better if they go into production. They will make a foolproof drill jig. So.....what are they going to cost?

 

Price Should be very competitive. I need to be 100% sure that those Stone headers are 100% perfect and no single fitment probelm, before I do any Groupbuy!

I would guess $400 (shipped) for 10+ GB!

 

nashua, can u actually feel the extra 4hp?? damn the cl-s is soo much fuckin stronger in the cold.

 

One thing to report... initial impression... NO resonance sound just a louder exhaust note!

 

I once bought a set of OBX headers for $300-something shipped (whatever the lowest deal was, I forget now... I resold them for more later when they were OOS anyway), and I wouldn't pay any more for these than I would for the OBX. Okay, maybe $50 more. But honestly stick with stock exhaust manifolds or get Comptech headers.

 

JRock,

So do you think that $400 for those headers (shipped) is a fair deal?

 

More hole alignment problems.

These manufacturers do such a good job copying Comptech’s PIPE design, why can’t they get the placement of (5) holes correct???

Shawn S

 

Im confused? Isn't the green graph line the dyno from the OBX headers from before and the blue line is the stone headers? If so, then why in the 3rd to last graph is the green line making more hp than the blue line? I dunno, i am kinda drunk right now, maybe im just reading it wrong..........basically i guess im supposed to just know that the stone headers make more hp?

 

Simply, because of SAE correcting factor of 0.92 (for the blue line) versus 1.02 for the (green line)

This time runs were downgraded by 8% or some 17 WHP.
Last time runs were boosted by 2% or some 5 WHP.

 

They were around 4hp/4torque more than the OBX, right?

Assuming a perfect fit that doesn't require re-drilling holes, yeah that's fair, IMHO.

 

I was pleased to gain almost 20hp with the OBX considering I had no intake so that was restricting flow coming into the engine. I only did one pull at the end since it was 6:20 at night and I was supposed to meet my fiance' and friends at 6:00 for a 6:30 movie. Fortunately the theater was just down the road and I made it there just before the previews started (saw Daredevil...cool flick). There is definitely an annoying resonance at around 2600rpm but it goes away +/- 100rpm. That kinda sux that there is any noice at all. There is also currently a low hum when idling. MAybe once everything settles in that might go away (?). Anyone else have this hum on their OBX? The exhaust tone is a little different, not better or worse. VTEC sings a little louder too. In any case, I haven't really ripped it up with the new headers but on the way home it definately felt a lot stronger. Hey, a 10% increase in hp is great any day. I am sure once I put the Icebox on then I will get more gains all around. But, 220whp with just headers is pretty nice I guess. I'll post my dyno graph a little later so don't go posting that "this thread is worthless without pics" thing!!!!

 

Oh, and thanks to Nashua for making this happen and thanks to Bulldog for showing up for a while. You are probably glad you didn't stick around. With the bolt alignment problems, it took 5+ hours (!!!) for the Stone install with dyno and 2 hours with dyno for the OBX. They just slid right on.

 

did you use the OBX gaskets or the stock ones? I am glad that you are enjoying the headers.. as for the resonance sound... I noted that once the car is warmed up, I would barely hear it!

 

Gary thought that the OBX gaskets were the right ones to use. The stock ones can barely qualify as a gasket.

 

So according to SAE corrections the OBX made more power? I saw the temp difference, hence the correction factor, so damn, now im not sure what headers to get........the only reason i might go against getting the OBX is because of the resonance, but hopefully the Stone prototype's holes will be aligned.

Any word on when the stone headers may be released?

 

No... The Stone Headers made 4 WHP (SAE) and (4 lbft) more... Both headers were dynoed the same day. The OBX (run 004) netted 216 WHP (SAE) and the Stone Headers (run 006) netted 220 WHP (SAE).

I can guess that once my test-fitting notes has been taken into consideration, the mass production should start very soon. Next week or so, I will start taking GB Pre-orders. I need to get the fittment issues resolved first!

I will keep you all posted.

 

Hey Nash,

Will the group buy be for us TL folks too?????

 

Yes... for all... TL CL and Accord V6... However, I am not a paying member on the TL board so I can post the GB there...

 

If they align the holes right and can assure us of no other fitment problems, count me in.

 

I am working hard on resolving the misalignment issues!

Stay tuned

 

One question regarding the difference between the OBX and STONE headers. Are the ports/holes connecting to the engine block the same size? Are the OBX ports smaller than the STONE ports?

Thanks

 

The Stone headers are port matched the OBX headers are not.

Here is the difference in pictures:

Obx Vs Stock Headers:


Here is the difference Gaskets Overlayed:











Stone Headers:

 

g0t pic of stone headers on

 

Last saturday we were running short on time, I did not have time to take pictures after the installation....

I will take few pcits after we dig out of the snow storm

 

im new to the forum but i have been keeping up with the whole header thing after reding about some of the complaints with the obx headers making noise at 2600 rpm and looking at the pictures of the stock compared to the obx i can see why they make noise the gasket on the obx is clearly smaller than stock so think of it as a musical instrument you blow air over a reed it makes noisie same way on the gasket so if you were to port match the gasket to the head i think you could take care of the problem, and thats my two cents

 

The OBX gasket is a much heavier and thicker gasket than the stock one and is in fact larger than the stock gasket. Take a look at the pictures Nashua posted earlier in this thread.

 

I am sure that someone else has tried this, but I have emailed OBX about the resonance at 2500-2600rpm. I am curious what their answer will be. Perhaps wrapping the headers with some sort of teflon tape or heat-safe insulation might fix that problem? Anyhow, I'll post their reply (if I get one) to the forum.

 

is the stock gasket the copper one , also quick question you said that the holes were off on the stone headers why didnt you just oversize the holes with a larger dia. drill bit
thanks

 

Yup, the copper one is the stock one. It is REALLY thin which you can't really tell in the picture. The OBX (and the Stone) gaskets have a bit of squishable insulating material inbetween the perferated metal plates.

We didn't use any power tools because the guy at the shop was being kind of a pain in the arse and didn't want us to use his power tools without paying for the drill bits and stuff like that since he was already giving us a good deal on the install price. Long story. Better not to go there. The metal file worked eventually.