Results 1 to 9 of 9
Thread: Header and exhaust size
-
12-05-2006 #1
Registered User
- Join Date
- Nov 2005
- Location
- RI
- Posts
- 746
Header and exhaust size
Now that winter is here and my car is in storage I'm making a list of things to do next year. I think my exhaust system isn't to great. Right now I have 1 5/8 dynomax headers (were coated but they rusted through so I painted them black.) My exhaust is 2 1/2" tubing with a kink on each side then flowmaster 40 series mufflers to 2 1/2" over the rear end then 3" tips that hang lower than the rear quater. I was thinking that i could at least use a x-pipe, or go all out and get 1 3/4 doug's headers coated with magnaflow system (not sure on 2 1/2" or 3".) The engine is a 388 chevy with 10.8:1 cr, gm 2.02 heads, z-28 intake dual plane, 750 holley, and cam with 507 lift 235 duration @ 50 and 108 lobe seperation. I dyno'd the car it made 318rwhp and 315rwtq corrected. I also have run 12.9 at 106 in the 1/4. What do you guys think? Thanks in advance.
-
12-27-2006 #2
Registered User
- Join Date
- Nov 2005
- Location
- RI
- Posts
- 746
No opinions?
01-12-2007 #3
Starting The Transformation
- Join Date
- Aug 2004
- Posts
- 135
The 3" system for sure, unless you want to quiet it down for some reason but the x-pipe will also do that.
01-12-2007 #4
Registered User
- Join Date
- Nov 2005
- Location
- RI
- Posts
- 746
Thanks, I'm going to change my rockers also to 1.65, so should change lift to around .557. I was thinking 3" anyway because I'll proberly upgrade my engine in the future. I'm also going to get the 1-3/4 headers too.
01-12-2007 #5
-Moderator/Sponsor-
- Join Date
- Apr 2001
- Location
- The City of Fountains
- Posts
- 16,129
Dual 3 inch pipes is WAY overkill for your power level. Unless you want to spend money and not gain anything, what you have will carry you a long way before it becomes a restriction.
Andrew1970 GTO Version 3.0
1967 Cougar build
GM High-Tech Performance feature
My YouTube Channel Please Subscribe!
Instagram @dr__efi
I deliver what EFI promises.
Remote Holley EFI tuning.
Please get in touch if I can be of service.
"You were the gun, your voice was the trigger, your bravery was the barrel, your eyes were the bullets." ~ Her
01-12-2007 #6
Registered User
- Join Date
- May 2005
- Location
- Fontana, CA
- Posts
- 4,960
Agreed. Bigger is not always better and in your case is overkill.
Nick R.
69 Camaro - 383, 700R4, 12 bolt 3.55, Hotchkis, Bilstein, Global West, Morris Classic
08 HHR SS - Still Stock for now
Do you still believe in all the things that you stood by before? Are you out there on the front lines, or at home keeping score?
Do you care to be the layer of the bricks that seal your fate? Would you rather be the architect of what we might create?
01-12-2007 #7
Registered User
- Join Date
- Nov 2005
- Location
- RI
- Posts
- 746
So 2-1/2 magnaflow system will be better than my crappy kinked exhaust with flowmasters? So 3" is not needed and will have no power gain? My wallet is happier now.
01-12-2007 #8
Registered User
- Join Date
- May 2005
- Location
- Fontana, CA
- Posts
- 4,960
The Magnaflow will do better and the 3" will not only be useless, but may hurt low end power. happy wallets rejoice!
Nick R.
69 Camaro - 383, 700R4, 12 bolt 3.55, Hotchkis, Bilstein, Global West, Morris Classic
08 HHR SS - Still Stock for now
Do you still believe in all the things that you stood by before? Are you out there on the front lines, or at home keeping score?
Do you care to be the layer of the bricks that seal your fate? Would you rather be the architect of what we might create?
01-12-2007 #9
Starting The Transformation
- Join Date
- Mar 2005
- Location
- florida
- Posts
- 181
exhaust?
thats kind of the system im looking to do with an ls1.2.5 with x member and magna flows.how do the magna flows sound?how do they compare with quieter flow masters?never have heard them.justy read that they flow pretty good.
Reply With Quote
