High boost with stock downpipe, how retarded am i? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Prefabbed Turbo Kits A place to discuss prefabricated turbo kits on the market
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools
Old 08-22-2007, 11:04 PM   #1
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Oct 2006
Location: Cincinnati, OH
Posts: 375
Total Cats: 0
Default High boost with stock downpipe, how retarded am i?

I've got pretty much everything required to run big boost sitting in my garage. The only thing i don't have is a downpipe, and my budget is running thin. I can weld and MIGHT be able to fab one, but if i fail, is there any danger to running 15+ pounds on the stock pipe besides taking all day to spool?
StankCheeze is offline   Reply With Quote
Old 08-22-2007, 11:26 PM   #2
Junior Member
iTrader: (2)
 
Join Date: Dec 2004
Posts: 201
Total Cats: 1
Default

Holy crap, I was getting 7 psi at 4500rpm ... I can't imagine what 15 would take =P Then again, I was on the stock exhaust as well =P
db84drteg is offline   Reply With Quote
Old 08-22-2007, 11:33 PM   #3
I'm Miserable!
iTrader: (1)
 
Join Date: Oct 2005
Location: Columbia, SC
Posts: 858
Total Cats: 0
Default

the first few psi is what takes some effort to create. After 5 its pretty easy to make whatever boost you want
SloS13 is offline   Reply With Quote
Old 08-23-2007, 01:27 AM   #4
Elite Member
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

kotomile is offline   Reply With Quote
Old 08-23-2007, 02:32 AM   #5
I'm Miserable!
iTrader: (5)
 
Join Date: Sep 2005
Location: SLC, Utah
Posts: 1,591
Total Cats: 0
Default

bottlenecked exhaust gas can blow head gaskets.
zoom2zoom is offline   Reply With Quote
Old 08-23-2007, 03:42 AM   #6
Elite Member
iTrader: (5)
 
akaryrye's Avatar
 
Join Date: Jul 2006
Location: Central California
Posts: 2,526
Total Cats: 0
Default

It would probably work, just gonna be slower response and boost control problems. Also apparantly the threat of head gasket issues. gl
akaryrye is offline   Reply With Quote
Old 08-23-2007, 11:44 AM   #7
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Oct 2006
Location: Cincinnati, OH
Posts: 375
Total Cats: 0
Default

Quote:
Originally Posted by zoom2zoom View Post
bottlenecked exhaust gas can blow head gaskets.
Perfect, that'll make me get off my *** and finally do my DIY head porting on the spare head sitting in my garage
StankCheeze is offline   Reply With Quote
Old 08-23-2007, 11:55 AM   #8
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,822
Total Cats: 1,781
Default

I dont see how high backpressure will blow head gaskets.....

I can see it increasing the intake temps and causing detontation.....but not just blowing out a head gasket....
Braineack is online now   Reply With Quote
Old 08-23-2007, 11:58 AM   #9
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

10-12 psi is more likey. and power that will come on like a lightswitch after 5k.
Ben is offline   Reply With Quote
Old 08-23-2007, 01:35 PM   #10
Senior Member
 
Join Date: Mar 2007
Location: Denver, CO
Posts: 564
Total Cats: 0
Default

On my Talon I ran 26psi through the stock exhaust with a gutted cat. It doesn't blow head gaskets, it's just somewhat counter productive. I was trying to get the best quarter mile time I possibly could one night with what I had, but in general turning up the boost before optimizing your exhaust is *** backwards. I'd also upgraded the turbo with one I had laying around, which once again is *** backwards on a stock exhaust. But it was a fun time.
jwarriner is offline   Reply With Quote
Old 08-23-2007, 03:57 PM   #11
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Oct 2006
Location: Cincinnati, OH
Posts: 375
Total Cats: 0
Default

Quote:
Originally Posted by jwarriner View Post
On my Talon I ran 26psi through the stock exhaust with a gutted cat. It doesn't blow head gaskets, it's just somewhat counter productive. I was trying to get the best quarter mile time I possibly could one night with what I had, but in general turning up the boost before optimizing your exhaust is *** backwards. I'd also upgraded the turbo with one I had laying around, which once again is *** backwards on a stock exhaust. But it was a fun time.
I know it's *** backwards, but the only things I buy new are tires. Downpipes don't come around that often
StankCheeze is offline   Reply With Quote
Old 08-23-2007, 04:27 PM   #12
Senior Member
 
Join Date: Mar 2007
Location: Denver, CO
Posts: 564
Total Cats: 0
Default

Ok. Well to answer your question, assuming a good tune with no knock, there is no inherent danger in this unless you run into the surge line on your compressor map (which I doubt in this case).
jwarriner is offline   Reply With Quote
Old 08-23-2007, 04:41 PM   #13
Elite Member
iTrader: (6)
 
Loki047's Avatar
 
Join Date: Sep 2005
Location: Chicago
Posts: 4,145
Total Cats: 0
Default

Isnt a tony dp on sale now?
Loki047 is offline   Reply With Quote
Old 08-23-2007, 05:53 PM   #14
:(
iTrader: (7)
 
Join Date: Jul 2006
Location: nowhere
Posts: 8,281
Total Cats: 2
Default

Quote:
Originally Posted by db84drteg View Post
Holy crap, I was getting 7 psi at 4500rpm ... I can't imagine what 15 would take =P Then again, I was on the stock exhaust as well =P
I get like 13 psi by then geez.
magnamx-5 is offline   Reply With Quote
Old 08-23-2007, 06:00 PM   #15
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Oct 2006
Location: Cincinnati, OH
Posts: 375
Total Cats: 0
Default

Quote:
Originally Posted by Loki047 View Post
Isnt a tony dp on sale now?
Yeah, but with a welded on cat, so the owner is unlikely to separate. I'm not much for cats, much more of a dog person
StankCheeze is offline   Reply With Quote
Old 08-23-2007, 10:18 PM   #16
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,822
Total Cats: 1,781
Default

Quote:
Originally Posted by magnamx-5 View Post
I get like 13 psi by then geez.
still got the stock exhaust?
Braineack is online now   Reply With Quote
Old 08-23-2007, 10:22 PM   #17
:(
iTrader: (7)
 
Join Date: Jul 2006
Location: nowhere
Posts: 8,281
Total Cats: 2
Default

nope 2.5 inch lemme check a DL MBC is killing me i get anywhere from 12-14 psi by 4500, and i get oscilations of 1-2 psi until redline with the MBC set to 15 psi. I need to get off my *** and get inside MS to figure out this ebc, and spark ****. No cat +dynamax truboflow muffler.
magnamx-5 is offline   Reply With Quote
Old 08-23-2007, 10:35 PM   #18
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,822
Total Cats: 1,781
Default

yeah well they're talking about with the stock exhaust....i wouldn't expect anything better.
Braineack is online now   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 57 07-19-2017 05:11 PM
WTB MP62 (Hotside) (NB2) Rick02R WTB 3 01-03-2016 08:18 PM
Going back to stock. Need some 1.6 parts. Trent WTB 2 10-01-2015 01:15 PM
01-05 Fab9 PNP COPs (used) FrankB Miata parts for sale/trade 6 09-30-2015 12:48 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 02:49 PM.