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Discussion Starter #1
just wondering if there is any hazards running an open ddp. My friend was saying that it could ignite the gases and fire back internally being that short.... but i know there will big pops and be loud as hell, but just curious if there is anything ot be worried about. thx.

and yes i tried to search.
 

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Ask your friend to explain how this might occur - ask him to be specific. I'm dying to hear how deep the B.S. gets once he starts shoveling....
 

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Discussion Starter #5
lol ill find out, but all he said is its easy for the gases to ignite, also that it burns ur valves, but i think thats only directed to n/a's... itll only be for a littl ebit until i get the extra money for the full 3".
 

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i have been running open dp for a year no problems and lots of others havent had any problems too and the popping is normal! sounds like pop corn, makes ya hungry does it not? :lol:
 

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Discussion Starter #8
lol it would only be for a week. cuuuz its like i have enough for the ddp, plus a bit, but my bday is the week after so:) lol so none of the flames will burn anything under there would they :p
 

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no they wont! also u can really smell gas bad if u were to crack the window so if ur gonna open the window might as well roll it all the way down!
 

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ma70-7m=1JZ
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When running with an open dp, you might loose some tourque but gain about 10 rwhp. I did some dyno testing with different downpipes with and with out exhaust. I dont have the sheets right here but thats what I recall. The only problem you could have is melting and maybe catching the under coating on fire undernieth the car. A good idea would be to bolt on a turn down type bend at the end of the dp. I think I am going to start making those.....
 

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Moderator, Aight Peace
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becauseican said:
When running with an open dp, you might loose some tourque but gain about 10 rwhp. I did some dyno testing with different downpipes with and with out exhaust. I dont have the sheets right here but thats what I recall. The only problem you could have is melting and maybe catching the under coating on fire undernieth the car. A good idea would be to bolt on a turn down type bend at the end of the dp. I think I am going to start making those.....
That and you can do damage to the parking brake cable... aight peace :chicken:
 

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the clever guy
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CO poisoning is a moderate risk and you could end up smelling like a shop rag. I ran open DP for about a month once (never again) and my center support bearing got pretty crispy and the noise was a challenge to my sanity after a couple of weeks. You'll probably get a kick out of it since your just running open for a week. One more thing, if you pop an IC coupler STOP. That's where you could get a fire. Have fun!
 

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Madd Tyte JDM yo ®
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open DP causes no damage

i ran my defcon DP open for the entire tiem my car was on the road.

all i got was an undercarriage coated w/ carbon and carbon on my rear end. nothing was burned, no hints of meltery or anything.

the parking brake cable is near impossible to burn as its placed all the way at the top of the driveshaft tunnel, and there is a nice big driveshaft and carrier bearing separating the DP and cable.

most downpipes extend to the rear of the tranny, after that, there is nothing else back there that could ignite easily.

it would take quite a long flame and no turblent airflow for something to catch on fire... i mean, a 5second flame at 0mph. i only got split second flames. while they were very large and lit up the entire undercarriage, rarely lasted more than a second. i was just under my car today and saw no meltage or burnery... just alot of carbon everywhere.

dont worry about hurting anything.

the reason you hear pops and backfires and flames is because of an rich condition. this means all the oxygen is burnt out of the mixture and the exhaust still has unburnt fuel. so as this unburnt fuel exits the downpipe, the exhaust temp is so high that once fresh air is introduced, combustion begins again. its impossible for the flame to travel up the downpipe and damange any engine parts for a couple reasons; one, the exhaust flow is so fast that the flame front couldnt travel quick enough to reach the valves under heavy load/high rpm usage. two, there is no more oxygen in the exhaust to ignite with the fuel in order to create a medium to transmit flame travel.
 

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Back to boosting!
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Don't forget, I ran a 1 foot exhaust (first dp bend) for a while...loud as hell sounded real mean, but no probs with anything burning...then end of the pipe didn't even stick outta the engine bay :D :D
 

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I put on a 2 1/2'' turn down on my open DP. I cut it off infront of the car cause my bolts were rusted to hell and back. Makes it nice and aggressive sounding but might piss of your lady after awhile like mine was.
 

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Dissident
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Yeah, if it's only temporary, bolt it up to your stock exhuast. A ran an open downpipe for a trip to get welder wire (for my catback) and didn't enjoy it. It felt like I was driving a 3500 lb chainsaw.
 

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greasemonkey
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itll sound like a damn mac truck when the turbo spools and will be loud as hell when you get on it. btdt.
 
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