Just had one die on me yesterday, I hope this fuss about DMH's customer service is not true but I will try to call them in the morning and hopefully I can get a replacement soon...

 

I have a brand new in box set of 2.5in low-pro DMH cutouts. Its the complete set with gaskets and all. I was asking $350, theyve never been used at all. Im in L.A. so let me know if youre intrested.

 

i have the qtp cutouts on my car now.. i'm running b&b tri flow shorty headers.. cutouts directly after them.. custom x pipe. and b&b catback.

car sounds pretty loud with them open.. closed seems quiet to me again

 

That sucks man. As far as getting a hold of them, Cajun has had no luck it seems via phone call or email. Hope it works out for ya. Good luck!

 

a 100hp gain on a boosted car is NOT bs. If the boosted car has a restricted exhaust to begin with, and then these are added, and the car was making 600+hp with the restrictive exhaust, you can almost guarantee it will pick up another 100hp, its simple air flow physics.

I did the exact thing to my car, added the dmh oval cutouts.

In addition, I had a guy build a custom circut that is attached to an rpm switch, this AUTOMATICALLY opens them once the car gets above x (3500)rmph, and automatically closes them once the car falls back below 3400 rpm.

THIS IS EXTREMELY IMPORTANT ON FORCED INDUCTION CARS THAT TOGGLE BETWEEN A RESTRICTIVE EXHAUST AND AN OPEN CUTOUT, FOR IT AFFECTS THE TUNE AND THE A/F MIXTURES!!!!!

Having the car tuned with them CLOSED, and then opening them, WILL CAUSE THE CAR TO RUN LEAN AND POSSIBLY DETONATE A MOTOR!!!

Therefore, either a seperate tune is needed for them open, and them closed... or you have to have them consistantly open at a specific rpm EVERY TIME, and then you can get away with one tune.

I tried to set them at an rpm that i never get to unless im trying to go fast.

I have an f1r, etp245cc race heads, 90mmTB, 383 forged lunati ls6, high flow long tube headers, straight 3inch exhaust through the tunnel, no cats, cutouts before the rear suspension, and the STOCK Z06 Ti MUFFLERS

 

Is this company still in business? Are they honoring their guarantee?

 

A couple of weeks ago I had one go out in under a year. I have called and sent an email, but so far no response. I'm not giving up yet as they could just be busy, but if I can't get a response soon I'll just ditch them.

 

When I called them a couple weeks ago the phone rang once and the owner picked up and was very helpful, turned out my cutout that I thought was bad was NOT but a rock or something hit the motor and "cocked" it to one side, some taps with the hammer and all is good. Either way the guy told me to send it in for another one

 

so i was bored today, and was going through my vette, trying to figure out a perfect spot to put the cutout switch for the dmh's. We have the rpm relay circuit, but i still had to put the manual override somewhere convinient INCASE the rpm switch relay failed as I went into boost. So I was trying to put it somewhere that i could get to the switch fast. Then I got to thinking, I wonder if i could put it IN the shift **** on my 6 speed? So i took the **** appart, but there was no room in there for it. Then i got to thinking about a home made shift ****... and for those of you who dont know me, the second thing i like behind fast cars is playing pool... its how i paid for food through college. So i got a cue ball, a 3 ball and an 8 ball from my table, and i figured what the hell... lets try this. Cue ball was the prototype, I failed. 3 ball is red, so it matches the z06 accents of my car, so it was second to be tried. 3 ball was a success. I will make the 8 ball later this week and then have to make the tough decision which to use. In the meantime, i figured id flaunt my creation on corvette forum. The actual 3 is perfectly stright up once screwed onto the shift shaft. The cutout is out of the way of being bumped on accident, and lies perfectly between the index finger and your thumb. I could make more if anyone is interested, but im not going to lie, it looks perfect, but also took me 5 hours to do

 

Isn't there a vendor on here that has them on sale right now?

Side note: That is clean install Irun4cops!!

 

i bought a DMH cutout years ago for my RX7... i had emailed him in advanced and told him that it was going on a turbo rotary which is insanely hot compared to a piston engine and expressed my concerns about the heat. He assured me that it would hold up with no problems.
I ran it on my RX for about a year then did a track event at VIR with it and it melted the butterfly out of it... contacted him and he built one one out of stainless and shipped it out to me EXTREMELY quick. He also told me that if this one failed, he'd build me one out of Inconel... all of this was free of charge to me (after the initial purchase of course). I will definately buy from DMH again if the need arises.

I dyno'd my maggie equiped, heads, cammed,meth breathing ,highflow cats,and longtube header having C5 with the exhaust closed, then open and only saw a 7 rwhp increase over the stock Z06 Ti exhaust.

Hope this helps some people...

 

I have to say that I have had a complete change of view when it comes to Dave and DMH. I emailed Dave directly and he emailed me back promptly. I called him and explained to him I was missing a part of my cutout system. Dave not only took the time to ensure I had everything I needed, he also sent me the part at no cost. I can not say enough about how personable and customer friendly Dave is. There is not doubt he makes the best cutout on the market but he also stands firmly behind it and does EVERYTHING he can to make the customer COMPLETELY satisfied. Thanks Dave!

 

It's good to hear Dave came thru for you guys! I'll be purchasing a set in the near future.

 

i think corvette recycling sells them

 

That's very stand up. Glad you got to experience Dave's very good customer service. Enjoy the cutouts. They're insanely fun around the neighborhood and when some ricer pulls up next to you and starts throwing revs.

 

I heard you can weld these straight on without having to buy anything else. Is that true? How much should I expect to pay for the welding installation? I really want these, but can't decide on QTP or DHM. Thanks for your input!

 

Are there any old school (not electric) low-profile cutouts available? Like the flowtech's but only low-profile?
I would like something with the shape of the DHM cutouts, but that I could open manually with a few wingnuts.

Thanks,

 

It is true you can weld them on. They come with ends that are cut for the pipe you specify when ordering (2.5 or 3 inch). I cannot comment on the welding prices since I traded some HIDs for them, but expect around 100 dollars to get a nice welding job.

On a side note, the nice thing about the DMH cutouts is you get block off plates as well. So if a motor fails you can pull the electric part out and just install the blocking plate while it is off being fixed.

 

Anybody know what size the Kooks X-pipe is? 2.5 or 3.0 inch?

Thanks,

 

Cool deal. So just to make sure. I would want to get the 2.5" for a stock C5 exhaust? Thanks for the reply!