New Member RX-7 Technical Post your first technical questions here, in an easy flame free environment, before jumping into the main technical sections.

Which downpipe?

Thread Tools
 
Search this Thread
 
Old 06-27-12 | 01:07 PM
  #26  
Sgtblue's Avatar
Urban Combat Vet
iTrader: (16)
 
Joined: Oct 2003
Posts: 12,097
Likes: 922
From: Mid-west
Originally Posted by Rodgersrotaries
......FYI boost creep really doesn't have much to do with the exhaust. If your still using the stock turbos and your pushing enough thru them to get boost creep, they are not going to last long enough to worry about it.
Wrong. It has EVERYTHING to do with exhaust. And you can get it at stock boost levels on the twins (i.e. 10 psi). The stock twin wastegate is relatively small and as mentioned above, can be overwhelmed if there is too little backpressure. And since it's exhaust volumn where talking about, it would proabably have more to do with rpm than psi.
To avoid it you either maintain some backpressure in the system (hi-flow cat is usually enough) or port the wastegate.
Old 06-28-12 | 10:35 AM
  #27  
FD7KiD's Avatar
2SoonJr

iTrader: (8)
 
Joined: Mar 2008
Posts: 525
Likes: 5
From: OrangeCounty-Santa Ana
Originally Posted by Sgtblue
Wrong. It has EVERYTHING to do with exhaust. And you can get it at stock boost levels on the twins (i.e. 10 psi). The stock twin wastegate is relatively small and as mentioned above, can be overwhelmed if there is too little backpressure. And since it's exhaust volumn where talking about, it would proabably have more to do with rpm than psi.
To avoid it you either maintain some backpressure in the system (hi-flow cat is usually enough) or port the wastegate.
so invest in a good high flow cat like Petit and port the wastegat a lil to avoid some boost creep
Old 06-28-12 | 11:06 AM
  #28  
NVMYRX-7's Avatar
If it's fast I'm There
iTrader: (24)
 
Joined: Nov 2005
Posts: 852
Likes: 0
From: Waxhaw, NC
Originally Posted by akagi's_white_comet
QUESTION
i have a Petit DP mated to my stock main cat and catback.
would changing my main stock cat with Petit Resonated Midpipe or Catless Midpipe with my Petit DP and Stock Catback lead to a blown motor?? i dont have a PFC or haven't moded the wastegate to make it bigger.
The answer is YES, the rotary doesn't like guess work !

Originally Posted by Gringo Grande
Bonez DP or Bonez Highflow Cat is about as best as you will do. Great fitment and quality!
^^^^^^THIS IS YOUR ANSWER !

Originally Posted by akagi's_white_comet
so invest in a good high flow cat like Petit and port the wastegat a lil to avoid some boost creep
I think you might be confused w/HF Cat vs. Pettit resonated midpipe. Don't put a resonated midpipe on a stock car! Simply get you a Bonez HF cat to go w/your Pettit DP and be done with it!
Old 06-29-12 | 10:50 AM
  #29  
FD7KiD's Avatar
2SoonJr

iTrader: (8)
 
Joined: Mar 2008
Posts: 525
Likes: 5
From: OrangeCounty-Santa Ana
I think you might be confused w/HF Cat vs. Pettit resonated midpipe. Don't put a resonated midpipe on a stock car! Simply get you a Bonez HF cat to go w/your Pettit DP and be done with it!
i think the confused one here is you Sir

http://shop.pettitracing.com/pettit_.../i-408896.aspx
Old 07-01-12 | 02:56 PM
  #30  
BoschFD's Avatar
Junior Member
 
Joined: Jun 2012
Posts: 9
Likes: 0
From: Germany
have a Feed downpipe.But with the HKS you makes definitely nothing wrong.
Old 07-01-12 | 06:44 PM
  #31  
myfirstfd's Avatar
Junior Member
 
Joined: Jul 2012
Posts: 15
Likes: 0
From: indiana PA
wow alot of good information should help me out later..
Old 07-01-12 | 09:34 PM
  #32  
TheDarkSide's Avatar
Junior Member
iTrader: (3)
 
Joined: Jul 2012
Posts: 25
Likes: 0
From: Illinois
Rx7 store makes a decent downpipe for the price, couple that with their mid pipe and a boost controller to prevent creep and you have some nice gains for cheaper.
Old 07-02-12 | 06:00 AM
  #33  
Sgtblue's Avatar
Urban Combat Vet
iTrader: (16)
 
Joined: Oct 2003
Posts: 12,097
Likes: 922
From: Mid-west
Originally Posted by TheDarkSide
Rx7 store makes a decent downpipe for the price, couple that with their mid pipe and a boost controller to prevent creep and you have some nice gains for cheaper.
WRONG! In another thread you suggested throwing an S5 OMP in the trash without knowing the consequences. Now you're suggesting putting a midpipe on and claiming that a boost controller will protect you from boost creep. It will not. Boost controllers control boost SPIKE. They do NOTHING for boost CREEP, which is caused by people throwing on midpipes without knowing the consequences.
Please do more reading. Your posts are not only wrong, but can cost someone alot of money.
Old 07-03-12 | 10:39 AM
  #34  
TheDarkSide's Avatar
Junior Member
iTrader: (3)
 
Joined: Jul 2012
Posts: 25
Likes: 0
From: Illinois
Originally Posted by Sgtblue
WRONG! In another thread you suggested throwing an S5 OMP in the trash without knowing the consequences. Now you're suggesting putting a midpipe on and claiming that a boost controller will protect you from boost creep. It will not. Boost controllers control boost SPIKE. They do NOTHING for boost CREEP, which is caused by people throwing on midpipes without knowing the consequences.
Please do more reading. Your posts are not only wrong, but can cost someone alot of money.
No ya big douche I was being sarcastic about the omp as how is it causing limp mode when hundreds of people don't run an omp whatsoever, maybe you don't know as much as you think. How many 3rd gens have you owned? I've had 3 all running straight exhaust and intake with no boast creep or boost spike. So relate actual facts from the real world please.
Old 07-03-12 | 12:19 PM
  #35  
Gringo Grande's Avatar
1.5 Goodfella's Tall

iTrader: (97)
 
Joined: Oct 2006
Posts: 4,216
Likes: 2
From: Tampa, FL
No ya big douche I was being sarcastic about the omp as how is it causing limp mode when hundreds of people don't run an omp whatsoever
An S5 will run in limp mode with no OMP unless you have some sort of solution that takes this into account...such as an RTEK. If you are suggesting otherwise, you are the only person I've ever seen claim this and would also feel you are wrong.

Suggesting someone run a DP and MP with just a boost controller is poor advice. I'm happy that you have had no catastrophic experiences with this combination...someone else may not be so lucky.

While time spent on the forum and posts is not always indicative of knowledge, you are giving the appearance of providing less than solid advice.

It would be interesting to hear your supporting mods for running a straight exhaust and intake with no boost creep or spike. You are apparently the only FD owner in history never to experience these issues.
Old 07-03-12 | 02:35 PM
  #36  
Sgtblue's Avatar
Urban Combat Vet
iTrader: (16)
 
Joined: Oct 2003
Posts: 12,097
Likes: 922
From: Mid-west
Originally Posted by TheDarkSide
No ya big douche I was being sarcastic about the omp as how is it causing limp mode when hundreds of people don't run an omp whatsoever, maybe you don't know as much as you think. How many 3rd gens have you owned? I've had 3 all running straight exhaust and intake with no boast creep or boost spike. So relate actual facts from the real world please.
Please...you weren't being sarcastic....you were simply being wrong. Probably just one of the reasons you've gone through three FDs.
Hundreds of owners do remove the OMP, but not on the stock ECU.
Old 07-03-12 | 02:54 PM
  #37  
gracer7-rx7's Avatar
needs more track time
iTrader: (16)
 
Joined: Mar 2006
Posts: 9,383
Likes: 608
From: Bay Area CA
Originally Posted by TheDarkSide
No ya big douche

There is absolutely no reason for that. Read and follow the rules for the forums or you will be banned. I issued you an infraction for this and closed your FS thread. Prove yourself as someone that can be trusted and follow the forum rules and common decent human behavior where you don't resort to child like insults to try and make a point.


BTW, Gringo and Sgtblue gave the correct advice and mirrors my own experience with these cars.
Old 07-03-12 | 04:56 PM
  #38  
GoodfellaFD3S's Avatar
Original Gangster/Rotary!
Veteran: Army
iTrader: (213)
 
Joined: Mar 2001
Posts: 30,580
Likes: 567
From: FL-->NJ/NYC again!
Arrow

Originally Posted by TheDarkSide
Rx7 store makes a decent downpipe for the price, couple that with their mid pipe and a boost controller to prevent creep and you have some nice gains for cheaper.
You're wrong. Boost creep is basically 'RX-7 101' and you're failing in this rudimentary topic.

Originally Posted by TheDarkSide
No ya big douche I was being sarcastic about the omp as how is it causing limp mode when hundreds of people don't run an omp whatsoever, maybe you don't know as much as you think. How many 3rd gens have you owned? I've had 3 all running straight exhaust and intake with no boast creep or boost spike. So relate actual facts from the real world please.
3 FDs does not exactly make for a huge sample size, sorry. Believe it or not, there are people on this board who may possibly know a bit more than you. Crazy but true.

You continue to be wrong, and now you're insulting a veteran member.

So, now you've got my attention and I'm not nearly as nice as the other guys posting above me. Just to hammer home the point----- if you don't change your attitude (and what you post) immediately, you'll be shown the door with a quickness.
Old 07-04-12 | 03:58 PM
  #39  
TheDarkSide's Avatar
Junior Member
iTrader: (3)
 
Joined: Jul 2012
Posts: 25
Likes: 0
From: Illinois
If it wasn't 100 degrees I'd make a video proving in real life situations those mods and a mbc will not do not creep or spike.....just because I don't have 500000 posts doesn't mean I'm a liar.....did the forum change owners BC it never used to be like this.....can any of you provide a video to counter argue mine? Thanks I'd love to learn something cause I'd hate to blow a motor.
Old 07-04-12 | 10:08 PM
  #40  
GoodfellaFD3S's Avatar
Original Gangster/Rotary!
Veteran: Army
iTrader: (213)
 
Joined: Mar 2001
Posts: 30,580
Likes: 567
From: FL-->NJ/NYC again!
Lightbulb

Originally Posted by TheDarkSide
If it wasn't 100 degrees I'd make a video proving in real life situations those mods and a mbc will not do not creep or spike.....just because I don't have 500000 posts doesn't mean I'm a liar.....did the forum change owners BC it never used to be like this.....can any of you provide a video to counter argue mine? Thanks I'd love to learn something cause I'd hate to blow a motor.
Search under my username and 'boost creep' and you'll get your answer.

Just because YOU haven't had this issue doesn't mean that others won't.

You can't cure a mechanical condition (the OEM wastegate being overwhelmed with too much exhaust flow) with a boost controller. Period. Many many owners have learned the hard way that a well-flowing system with stock twins/stock WG=17+ psi on stock map sensor/fuel=blown motor.

Excuse us if we're kind of cranky after having to explain this for about the 20 millionth time.
Old 07-04-12 | 10:29 PM
  #41  
TheDarkSide's Avatar
Junior Member
iTrader: (3)
 
Joined: Jul 2012
Posts: 25
Likes: 0
From: Illinois
Fair enough, I guess the point I was trying to make is that just because it hasn't worked for others doesn't mean it can't work. I duno why it has always worked for me, I spent $11 on a boost controller, $5 in parts from ACE and $6 in ice cream sandwiches and it has not failed me once, but I pushed this 7. That being said, thanks for the welcome and not banning me, I never mind a heated discussion. And I don't need to search you Ive seen your youtube videos..lol


Originally Posted by GoodfellaFD3S
Search under my username and 'boost creep' and you'll get your answer.

Just because YOU haven't had this issue doesn't mean that others won't.

You can't cure a mechanical condition (the OEM wastegate being overwhelmed with too much exhaust flow) with a boost controller. Period. Many many owners have learned the hard way that a well-flowing system with stock twins/stock WG=17+ psi on stock map sensor/fuel=blown motor.

Excuse us if we're kind of cranky after having to explain this for about the 20 millionth time.
Old 07-04-12 | 11:26 PM
  #42  
GoodfellaFD3S's Avatar
Original Gangster/Rotary!
Veteran: Army
iTrader: (213)
 
Joined: Mar 2001
Posts: 30,580
Likes: 567
From: FL-->NJ/NYC again!




All times are GMT -5. The time now is 05:51 PM.