hotside dump tube how much power

[RNR_MOTORS]

how much horsepower do u get by adding the hotside dump tube also what are the pros and cons

also do i need to retune after adding a dump tube and a co2 ring?? i need to know thanxs everyone

 

[the_mork]

Well Scott, now that you're agreeing that the turbulence might be a possibly hp suppressing issue... what about the exhaust scavenging effects that would be lost by dumping some of the exhaust to the atmosphere? It can go both ways. I would say, unless you're an expert and know FOR A FACT that something is a certain way, you should avoid spreading misinformation. It's how you end up with a forum full of people spouting out answers that are untrue.

There is no scavenging post-turbo. There really isn't any scavenging at all.

 

[FactoryChrome]

Can you explain that more? If there's scavenging in an NA motor because of exhaust pulses leaving the system, how is this not happening in a turbo application?

I'm not implying you're wrong, I'd just like some more info on it.

 

[toofast82]

I recently seen a thread on srtforums, where the guy lost 38whp by re-routing his dump back into the exhaust. He took it back off, put a muffler on it, , redynoed and gained it right back,
http://www.srtforums.com/forums/f24/tale-dump-tube-different-approach-power-loss-perfection-315402/

 

[mindset]

Scott, you really do throw in a lot of words. Just get to the point.

An O2 dump prevents exhaust gases from reaching the turbo to control boost levels and not blowing up your car. It's a cheap cure to boost creep. There is no significant evidence in any horsepower gain.

 

[FactoryChrome]

I recently seen a thread on srtforums, where the guy lost 38whp by re-routing his dump back into the exhaust. He took it back off, put a muffler on it, , redynoed and gained it right back,
Tale of a dump tube .... a different approach ; power loss to perfection ! - SRT Forums - SRT4, SRT6, SRT8, SRT10 & Dodge Forum

Does that not count as evidence or was it speculated horsepower that he picked up on the dyno?

 

[habitatguy187]

I recently seen a thread on srtforums, where the guy lost 38whp by re-routing his dump back into the exhaust. He took it back off, put a muffler on it, , redynoed and gained it right back,
Tale of a dump tube .... a different approach ; power loss to perfection ! - SRT Forums - SRT4, SRT6, SRT8, SRT10 & Dodge Forum

Awesome link

I've speculated for a long time that o2 dumps help more than what people say they do. I wonder what the gains off a 3.5" exhaust would be over a 3" on a 16g setup.

 

[toofast82]

Does that not count as evidence or was it speculated horsepower that he picked up on the dyno?

It's an srt4 and its not AWD, so it doesn't count j/k
I definitely think on higher horsepower setups, there can be something to be gained for sure from dumping to atmosphere over rerouting and causing turbulence in the exhaust stream. I was pretty shocked when I seen this thread to say the least though.
On a 200whp setup, the gain would most likely be pretty minimal. Also if I had 200whp, I certainly wouldn't want open dump roaring and the car not moving much

 

[mindset]

Does that not count as evidence or was it speculated horsepower that he picked up on the dyno?

Well I guess it does.
I haven't looked through all 5 pages but I haven't seen a single dyno sheet. The guy says he pushed well over 500whp, but who knows if he's talking out of his ass.

 

[1gDSM4g63]

Does that not count as evidence or was it speculated horsepower that he picked up on the dyno?

Off course!!! That scared me along those turbo whistling mufflers that sound like weed whackers too.

Although they do sound pretty badass on my car with the deep whooshing sound when the two wastegates open up, along with a 4" side exhaust and the Tial BOV. But having a side exhaust or a test pipe does help if you have a humongous turbo and the main reason why people go with dump tubes is because of the ease of less fabrication if you have a T3, T4, or T5 turbo.

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[toofast82]

Well I guess it does.
I haven't looked through all 5 pages but I haven't seen a single dyno sheet. The guy says he pushed well over 500whp, but who knows if he's talking out of his ass.

Why would he waste his time writing up the thread?
Why would he waste his time removing the dump from the rest of the exhaust when noise was his first issue in the first place?

If there was no difference, then his thread would have been about how he merged the dump with the rest of exhaust and felt no power loss and how he was happy that it was quiet now

Without a doubt the difference will vary with different power output levels, though

 

[mindset]

Why would he waste his time writing up the thread?
Why would he waste his time removing the dump from the rest of the exhaust when noise was his first issue in the first place?

If there was no difference, then his thread would have been about how he merged the dump with the rest of exhaust and felt no power loss and how he was happy that it was quiet now

Without a doubt the difference will vary with different power output levels, though

I wasn't saying he was right or wrong. It would make sense to post dyno sheets backing up what one would claim.

 

[1gDSM4g63]

I wasn't saying he was right or wrong. It would make sense to post dyno sheets backing up what one would claim.

Even if dump tubes do make a difference, it will be meager. I highly doubt you can show it on a dyno run because ever time you do a dyno run on the same tune the hp/tq rating will vary.

 

[toofast82]

I wasn't saying he was right or wrong. It would make sense to post dyno sheets backing up what one would claim.

I agree, it would make sense to show the dyno sheets so that there would be NO DOUBT.
But like I said, he was basically doing a write up of his impression of a vendor's recirculating dump pipe and his impressions and "said" results
I really don't see the reason to lie about it.
It's not like he's saying "I made 450whp on a 14b" and not showing dyno sheets, a 500whp+ srt4 is nothing new at this point

 

[mindset]

Even if dump tubes do make a difference, it will be meager. I highly doubt you can show it on a dyno run because ever time you do a dyno run the hp/tq will show somewhat different.

Ok. This guy claims he lost 39hp, then gained the exact 39hp amount back once dumped? So how much different?

I mean if it were to vary then saying you gain hp with an O2 dump is an inaccurate statement.

Just so you guys know, I'm not trying to be an arguing smart ass on purpose. This is a needed discussion.

 

[toofast82]

Ok. This guy claims he lost 39hp, then gained the exact 39hp amount back once dumped? So how much different?

I mean if it were to vary then saying you gain hp with an O2 dump is an inaccurate statement.

Just so you guys know, I'm not trying to be an arguing smart ass on purpose. This is a needed discussion.

Possibly if this guy had a 4" exhaust system and was recirculating, then maybe there wouldn't be so much, if any difference.
It is going to vary setup to setup and power to power whether there will be any gain.
Say on a 180whp with a 3" exhaust that is more than big enough, you may not gain anything because the added turbulence is not hurting the actual turbines exhaust flow from escaping.
Now say on a 500whp, where you may be cutting it close with 3" exhaust to begin with, dumping the wastegate to atmosphere may be more beneficial

 

[1gDSM4g63]

Ok. This guy claims he lost 39hp, then gained the exact 39hp amount back once dumped? So how much different?

I mean if it were to vary then saying you gain hp with an O2 dump is an inaccurate statement.

Just so you guys know, I'm not trying to be an arguing smart ass on purpose. This is a needed discussion.

Well, when I said varying in hp I meant like a difference of a few hp not 39 hp.

That guy is clueless, he probably thinks that an aftermarket exhaust will give 100 hp and a big ass spoiler will give another 50 hp.

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[mindset]

Possibly if this guy had a 4" exhaust system and was recirculating, then maybe there wouldn't be so much, if any difference.
It is going to vary setup to setup and power to power whether there will be any gain.
Say on a 180whp with a 3" exhaust that is more than big enough, you may not gain anything because the added turbulence is not hurting the actual turbines exhaust flow from escaping.
Now say on a 500whp, where you may be cutting it close with 3" exhaust to begin with, dumping the wastegate to atmosphere may be more beneficial

Agreed.

Well, when I said varying in hp I meant like a difference of a few hp not 39 hp.

That guy is clueless, he probably thinks that an aftermarket exhaust will give 100 hp and a big ass spoiler will give another 50 hp.

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Yes, , agreed also.
I used to have a red 87 Integra like that!

 

[toofast82]

Agreed.



Yes, , agreed also.
I used to have a red 87 Integra like that!

, did it have the same wing and rims?

Off topic, but I miss my 93 teg. Most reliable car I ever owned. I actually seen the kid i sold it too driving it yesterday. Of course it still runs,

 

[LiquidX]

Now say on a 500whp, where you may be cutting it close with 3" exhaust to begin with, dumping the wastegate to atmosphere may be more beneficial

I do actually agree with this. If you are pushing enough air to produce enough exhaust to allow the 3" exhaust to become a restriction, then it's POSSIBLE the dump may help as it's less gas in the pipes.

However, most builders will be calculating their flow to match the pipes wether it's 2.5", 4" or open downpipe. For most though, any sort of measurable gain IMO wouldn't be worth it if it's less than 5HP. The added noise (even with a muffler will still be loud) and the inablitly to pass a visual inspection for those that have it. It's an exhaust leak pre-cat which will fail.

I think that a recirculated o2 that enters the pipe at an angle with the flow wouldn't cause much turbulance at all and would reduce any back pressure from the entry point back as there is now smooth flow travel.

For that link, the guy made a claim with nothing to show so that's still a toss up wether it really does help to dump or not.

 

[mindset]

, did it have the same wing and rims?

Off topic, but I miss my 93 teg. Most reliable car I ever owned. I actually seen the kid i sold it too driving it yesterday. Of course it still runs,

No, haha, but it did have a modified sticker and a 1.8t logo off of a VW . Then I slapped a cleveland4g63 sticker right in the middle of it. I carved DSM's rule on the front hood hahaha then I scratched a GIANT mitsu symbol on the front hood I had so much fun with it, I paid $700 for it. It was the most reliable car and I also see my car everyday because I sold it to a good buddy of mine for super cheap.

NOT TO MENTION the COUNTLESS nuetral drops hahahaha

 

[91stocker]

Everyone saying theres no gain, wheres your proof, Why give advice with no data to back it? It would seem the most on this site talk out their arse, no offense.

It reminds me of another forum where everyone used an intake manifold from another car because they "believed" it to flow better. After people swapping to this intake for like 3 years someone dyno'd it and it showed a loss of 15hp and much less flow haha.

Srt guys and some evo guys have dyno results of o2 dump alone. An evo picked up 20whp on a decent build. It doesnt seem that out of line tbh, like for example 350hp v8 guys show nice gains with duel 3'' exhaust. Why wouldnt 350hp 4cyl show nice gains with a o2 dump on single 3"?

And sorry that was only aimed for the 100 replys to the same question that say " dont do it, its too noisy", or "port your o2 housing", or "no it will probably hurt performance if anything". Id like to see some more solid info on this topic as well.

 

[mindset]

Everyone saying theres no gain, wheres your proof, Why give advice with no data to back it? It would seem the most on this site talk out their arse, no offense.

It reminds me of another forum where everyone used an intake manifold from another car because they "believed" it to flow better. After people swapping to this intake for like 3 years someone dyno'd it and it showed a loss of 15hp and much less flow haha.

Srt guys and some evo guys have dyno results of o2 dump alone. An evo picked up 20whp on a decent build. It doesnt seem that out of line tbh, like for example 350hp v8 guys show nice gains with duel 3'' exhaust. Why wouldnt 350hp 4cyl show nice gains with a o2 dump on single 3"?

It's a vice-versa theory. I never said he was right or wrong, once again. There is no proof in increasing or maintaining HP. EDIT: Yet it depends on setup, like I said below.

And about that intake. It's like me putting a BW S300 turbo on my car and running 12psi. I'd lose HP because that turbo is made to run efficiently at a higher boost level. Like toofast82 said, it depends on mods, setups, and current WHP.

 

[91stocker]

Yea sorry wasnt aimed at anyone, just when i tried to look up info on this i had to check out other forums.
This question had been asked alot on here with no good info to say yes or no, just 100 replys saying "dont do it, its too noisy". Kind of frustrating reading 3 pages of those type of responses on every thread.

 

[toofast82]

All I'm gonna say is: I feel pretty confident to say that dumping to atmosphere WILL NOT hurt power output and the only potentially negative thing is the loud noise, which some people beat off to and others are very annoyed by.

I have ran across a thread or two on EVOm, where there were reported "solid" gains by going to an O2 dump, even on the 16g. It would take me some time to dig up, but i seen the srt one recently so i pulled it up quick.

 

[91stocker]

which some people beat off to and others are very annoyed by.

haha i bet

heres some decent talk on the subject

3" Downpipe vs. o2 Dump - evolutionm.net

wish i could find some dyno results with dump vs recirc
I think i could put up with the noise if there was a significant gain involved.