My new H-Body 3 Inch Downpipe and High-Flow Cat Assembly. - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

Reply
 
 
 
Thread Tools Search this Thread
Old 05-29-2006, 08:49 PM   #1
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: May 2006
Posts: 19
Thanks: 0
Thanked 0 Times in 0 Posts
DaveSSEi is on a distinguished road
Default My new H-Body 3 Inch Downpipe and High-Flow Cat Assembly.

Not trying to brag but just wanted to share info with everyone.
I just had a 3 Inch Downpipe and High-Flow Cat Assembly installed that I purchased from Hoganperformance.com. I'm sure it increased my HP by 11 HP. It is great sounding with my dual Dynomax Super Turbo Mufflers. Not raspy sounding. Not too loud either. It has a low mellow sound. Curt Hogan was very helpful when I had alot of questions that I needed to have answered.
NOTE: This is for the 97-03 Bonneville with a 3.8 *.C. or 3.8 N.A. engine.
Dave SSEi, 2001 (black).
DaveSSEi is offline   Reply With Quote
Old 05-29-2006, 09:07 PM   #2
Senior Member
True Car Nut
 
toastedoats's Avatar
 
Join Date: Sep 2004
Location: Fitchburg Ma _ToastedRice_
Posts: 6,837
Thanks: 0
Thanked 0 Times in 0 Posts
toastedoats is on a distinguished road
Default Re: My new H-Body 3 Inch Downpipe and High-Flow Cat Assembly

Quote:
Originally Posted by DaveSSEi
Not trying to brag but just wanted to share info with everyone.
I just had a 3 Inch Downpipe and High-Flow Cat Assembly installed that I purchased from Hoganperformance.com. I'm sure it increased my HP by 11 HP. It is great sounding with my dual Dynomax Super Turbo Mufflers. Not raspy sounding. Not too loud either. It has a low mellow sound. Curt Hogan was very helpful when I had alot of questions that I needed to have answered. Dave SSEi, 2001 (black).
11hp? where did you get that number?
toastedoats is offline   Reply With Quote
Old 05-29-2006, 09:23 PM   #3
Senior Member
True Car Nut
 
Join Date: Jul 2004
Location: Twin Falls, Idaho
Posts: 7,545
Thanks: 0
Thanked 1 Time in 1 Post
Hans is on a distinguished road
Default Re: My new H-Body 3 Inch Downpipe and High-Flow Cat Assembly

Quote:
Originally Posted by toastedoats
Quote:
Originally Posted by DaveSSEi
Not trying to brag but just wanted to share info with everyone.
I just had a 3 Inch Downpipe and High-Flow Cat Assembly installed that I purchased from Hoganperformance.com. I'm sure it increased my HP by 11 HP. It is great sounding with my dual Dynomax Super Turbo Mufflers. Not raspy sounding. Not too loud either. It has a low mellow sound. Curt Hogan was very helpful when I had alot of questions that I needed to have answered. Dave SSEi, 2001 (black).
11hp? where did you get that number?
their webpage:

http://hoganperformance.com/DP8S.htm
Hans is offline   Reply With Quote
Old 05-30-2006, 12:04 AM   #4
Senior Member
Certified Car Nut
 
Join Date: Oct 2003
Posts: 19,756
Thanks: 0
Thanked 0 Times in 0 Posts
1993 SLE is on a distinguished road
Default Re: My new H-Body 3 Inch Downpipe and High-Flow Cat Assembly

Quote:
Originally Posted by hoganperformance
This downpipe was developed to increase exhaust flow in the most restrictive area of the exhaust on the 97-03 Bonneville with a 3.8 SC and 9800 NA engine.
must have been the super secret verision

and they did 2 dyno pulls for each, and we all know that dyno pulls can vary from pull to pull...11hp...if your not decently modded you prolly lost lowend
1993 SLE is offline   Reply With Quote
Old 05-30-2006, 10:05 AM   #5
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

With the rest of the exhaust being 2.5 (assumption) his backpressure should still be there, however the initial pull would be stronger because of having a place to stack the exhaust.
BillBoost37 is offline   Reply With Quote
Old 05-30-2006, 01:33 PM   #6
Member
Posts like a V-Tak
 
Join Date: Jan 2006
Posts: 42
Thanks: 0
Thanked 0 Times in 0 Posts
Cwynn6 is on a distinguished road
Default

Quote:
Originally Posted by BillBoost37
With the rest of the exhaust being 2.5 (assumption) his backpressure should still be there, however the initial pull would be stronger because of having a place to stack the exhaust.
Stack the exhuast? WTF are you talking about. How long do you actually think it takes to fill that space with a volume of exhaust gas? Anyway, it makes more sense to have a smaller dp and a larger diameter exhaust tubing after the downpipe. The reasoning behind this is that the exhaust gas has the highest velocity exiting the ports and it'* fully expanded (heat). As it cools going the exhaust the gas slows but takes up less space. By going from 2.5" to 3" after the downpipe you are creating "backpressure" (which is one of the biggest myths in the automotive world ever).
Cwynn6 is offline   Reply With Quote
Old 05-30-2006, 02:23 PM   #7
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

CW...this is not the place for your debate. Back on topic please.
BillBoost37 is offline   Reply With Quote
Old 05-30-2006, 03:54 PM   #8
Senior Member
Posts like a Turbo
 
Join Date: Jul 2005
Location: Palatine, IL
Posts: 239
Thanks: 0
Thanked 1 Time in 1 Post
TommyGloves is on a distinguished road
Default

FWIW - I was the one that provided the dyno sheets to Curt. It was my car and my experiment. You can see the results here:

http://www.bonnevilleclub.com/forum/...=583005#583005

My mod list is in my sig. These results were with the stock cat and exhaust.

Congrats Dave...glad you're happy with the results.
TommyGloves is offline   Reply With Quote
Old 05-30-2006, 04:07 PM   #9
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

Tommy... great info and thank you for being one of the first, if not the first to give it a try.
BillBoost37 is offline   Reply With Quote
Old 05-30-2006, 04:11 PM   #10
Member
Posts like a V-Tak
 
Join Date: Jan 2006
Posts: 42
Thanks: 0
Thanked 0 Times in 0 Posts
Cwynn6 is on a distinguished road
Default

Quote:
Originally Posted by BillBoost37
CW...this is not the place for your debate. Back on topic please.
That was on topic. It'* just that you said something with no reasoning behind it. I was more on-topic than you were.

You should have posted that as your original reply "this is off topic." This whole thread is about a guy who is bragging about his new downpipe.
Cwynn6 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Just got a ZZP 3" Dowpipe and 3" high flow cat installed. Bwayney Performance, Brainstorming & Tuning 40 07-18-2009 10:02 AM
High flow cat - *UPDATED W/NEW INFO!* toastedoats 2000-2005 12 10-12-2006 04:03 PM
Will 17 inch Bonneville rims work on a GXP with 18 inch rims cballweg Bonneville GXP/ Northstar Powered Cars 5 01-25-2006 12:13 AM
High flow cat CraZyDriVer868 General GM Chat 16 09-04-2003 02:30 AM
High flow cat Sol Performance, Brainstorming & Tuning 18 06-02-2003 06:47 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 10:47 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.