joe@cpr.com Posted August 19, 2014 Share Posted August 19, 2014 Well Lashway motorsports gave us an amazing opportunity in giving our headers we produce right here in AZ a shot. This is a 100% copy and paste of their write up and pictures they took. I have not altered their text in any way. Below what they put I will address a few things in the article that they made note of. Here are the product details of these headers. -100% U.S. stainless steel -100% hand tig welded -U.S. v-band flanges -2'' primaries -Velocity spike -Conical merge collector -Hand ported flanges for a perfectly smooth transition -longest primaries on the market -OEM GM gaskets included -02 extensions included -Needed clamps for rear connections included ]CORDES PERFORMANCE HEADER TESTING & REVIEW INTRO: We had the opportunity last week to test a new set of headers for the 2014+ C7 Corvette by Cordes Performance Racing (CPR) of Mesa, Arizona. Joe, the owner of CPR was excited to have us test one of the first sets out. We were happy to take on the challenge, and give our opinions on quality, fitment, and of course their performance gains. These headers feature 2" primaries, V-band style connections, and high quality stainless steel construction. Our test vehicle was a 2014 Z51 with dual mode exhaust. Our buying experience with CPR and their staff was excellent. Prompt email and phone responses helped the process to move along smoothly. The headers took 4 days to arrive through ground shipping, and were packaged pretty well. The headers come complete with everything one will need to complete the installation including new GM MLS manifold gaskets - something no other company we have tested does. INSTALLATION: These headers are large, and somewhat bulky compared to ARH, Kooks, or Stainless Works. By "bulky" I mean heavy - solid - stout....whatever word you want to use to describe a well built set of headers. They feel great in your hands. These headers do require the engine to be lifted up about 2" which helps to slide them in place. We also opted to remove the starter motor which gave even more clearance. On Z51 models, the dry sump oil lines will have to be disconnected, and the oil drained. Do not forget to drain the oil completely from the pan, not just the sump lines themselves. Otherwise, you may overfill the engine when time comes to add oil! Once the headers were in place, I began bolting them onto the heads using the new manifolds, and the stock header bolts which (in my opinion) are more than sufficient enough for any performance car in term of strength, and reliability. They also have factory installed thread locker which keeps them from backing out after a few heat cycles. The headers bolted up well, and gave no fitment issues in or around the engine bay or frame. Yes, they are tight in some areas, but that is to be expected on a 2" primary. Anyone who has installed 2" headers in a C6 will know what I mean. I did have to adjust a brake line on the driver's side near the firewall to get it way from one of the primaries. The kit comes with 02 sensor extensions which I ran above the factory heat shield out of the way from the heat that is generated while the engine is running. I loved the V Band feature on these headers. We typically use these connections on high end turbo systems and exhausts where an exact, leak free fit is needed. A V-band will lever slip, or move - no matter the situation. The mid pipe fit well, but was not as precise of a fit as the ARH, Kooks, or Stainless Works which all leave a bit more wiggle room. V band connections are exact, which means the pipes have to merge perfectly, or they will not seal. The only fitment issues I had was between the mid pipe (x pipe) and the factory exhaust connections at the axle back. It was a bit tight in some areas, and clamping everything together was tough. Being that the car was on a lift at my shop made it a bit easier to handle, but I could see someone installing these at home having a tough time getting everything lined up perfectly. The clamps used to connect the x pipe to the connections leading to the axle back are a "band style" clamp which were also somewhat tedious to install. I had to install the clams first at the 12 o clock position in the tunnel, then put the exhaust together. This made it difficult to line everything up as the mid and connections pipes were already tightened. With some patience though, I got it. Once the system was installed, I was not happy with the clearance I had between the rear trans housing and the piping. I made some spacers, and spaced down the hanger bracket which bolts to the transmission. No big deal, but might have been an issue for someone at their home. Overall, I was happy with the fitment of the exhaust, but I will suggest some changes to Cordes to make it a bit easier for the next guy. I also added an additional 02 sensor bung to the passenger side of the x pipe for tuning purposes. Our tuner prefers to leave the front 02 sensors in place, and use a rear 02 bung for his wideband which provides more accurate readings. This system did not have any provisions for rear 02 sensors, so I had to add my own. The last part of the install was the tunnel plate. I did have to shim it down at the front of the tunnel just slightly to clear the large primaries. I used washers, but Joe at Cordes assured me that future kits will come with machined spacers...a nice touch. Otherwise, the tunnel plate bolted back into place normally. PERFORMANCE: We tested the Z51 using our own Mustang Dyno MD 500 we have here at the shop. The headers performed well, producing a final reading of 437 RWHP and 440 RWTQ - something that surprised us all. I expected a lower torque reading than what these produced. That was a gain of 22 RWHP and 36 FT LBS of torque! Excellent results for a larger primary header on a 6.2L. SUMMARY: Overall I was impressed with the fitment of the headers. The x pipe, and connection pipes were tedious to install, but fit in the end and did not rub or touch. I will suggest some tweaks to CPR, but will leave it up to them to make those changes should they feel they are needed. I think 2" primaries are too large for most C7's out there, and would never recommend them for someone with only bolt ons. They are better suited for blower applications, and larger than stock cubic inch engines. However, our test proves that they still perform well compared to other brands on the market. Below are my overall ratings on a scale of 1-10 CUSTOMER EXPERIENCE WITH CPR: 10 SHIPPING TURNAROUND: 10 PACKAGING: 7 FITMENT: 8 DIFFICULTY OF INSTALLATION (COMPARED TO OTHER BRANDS): 6 QUALITY: 10 VALUE: 8 PERFORMANCE GAIN: 8 -- Erik Bentley, President Lashway Motorsports, Inc. -The install notes they removed the starter, this is not needed and I feel they did so as the other brands require it. -The midpipe will be revised soon to be a one piece design, we did the two piece at first to allow customers who bought a high flow catted option, the ability to order just the front off road section should they go to such a high power level that cat's won't hold up to it. The tunnel being so much smaller on the C7 makes it a lot more challenging to do a big pipe and have the room to easily fit these. -Packaging: this was the first set we shipped and thus were still figuring out the box dimensions, in a nutshell the first set was shipped in a way to large of box and filled w/ lots of packing material. All orders moving forward will be in a much more tight fitting box w/ thicker material to help prevent any movement during shipment. All in all we are very proud that one of the leading Vette shop's in the nation gave us this amazing opportunity and did a truly unbiased write up. It's nice to prove that 2'' headers will pick up power everywhere even on a 100% bone stock car!! Quote Link to comment Share on other sites More sharing options...
TheCMSH Posted August 19, 2014 Share Posted August 19, 2014 Congrats Joe! Quote Link to comment Share on other sites More sharing options...
joe@cpr.com Posted August 19, 2014 Author Share Posted August 19, 2014 Congrats Joe! Thank you sir! Quote Link to comment Share on other sites More sharing options...
jmxp69 Posted August 19, 2014 Share Posted August 19, 2014 Yeah, nice review. Good to see the positive press. Quote Link to comment Share on other sites More sharing options...
Bromley's Corvettes Posted August 19, 2014 Share Posted August 19, 2014 Sounds like they just need a few minor little tweaks to be dialed in. They sure are pretty:) Quote Link to comment Share on other sites More sharing options...
Guest badbobs95 Posted August 19, 2014 Share Posted August 19, 2014 Great review Joe, just like I knew you would get. You know, because I'm so learned about these things! Quote Link to comment Share on other sites More sharing options...
P51tj Posted August 19, 2014 Share Posted August 19, 2014 Nice work Joe and Crew! Quote Link to comment Share on other sites More sharing options...
Buccaneer Posted August 19, 2014 Share Posted August 19, 2014 Nice review, congrats! Quote Link to comment Share on other sites More sharing options...
Grape Ape Posted August 19, 2014 Share Posted August 19, 2014 Nice... ...and congrats. Quote Link to comment Share on other sites More sharing options...
Two Fangs Posted August 20, 2014 Share Posted August 20, 2014 Very nice! Quote Link to comment Share on other sites More sharing options...
joe@cpr.com Posted August 20, 2014 Author Share Posted August 20, 2014 Thank you everyone!! Got a few new products coming out soon, we are going to bring back to market the Pfadt C5 diff mount which i'm really excited about as well. This will be made right here in AZ as well Quote Link to comment Share on other sites More sharing options...
Drewster67 Posted August 20, 2014 Share Posted August 20, 2014 Good stuff Joe - Congrats! Quote Link to comment Share on other sites More sharing options...
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