#1  
Old 12-08-2019, 03:46 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default Pussycat 505

I've got a 505 in my 65 GTO, 87 cc e-heads, dougs round ports, full Pypes exhaust with a 3" x pipe into 3", 20 inch long race pros, then tapers down to 2.5" tail pipes.

Right now I am just trying to make it a basic street car. When I idle the car in my shop at night, my wife says it can keep our 2 year old awake.

My current plan is to get rid of the 3" Race Pros and switch to 2.5" Dynomax Super Turbos, use the Flowmaster reducer cone in front of the muffler, and see if that makes a difference. Am I on the right track, or just a waste of money? I want the car to be as quiet as possible at idle.

  #2  
Old 12-08-2019, 04:09 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

also it idles about 1000 rpm on full manifold advance. was thinking about switching to ported to drop idle rpm and quiet it down more. does that sound reasonable and will it create oilng issue? i have the comp hydraulic roller lifters.

  #3  
Old 12-08-2019, 04:18 PM
HoneyHush HoneyHush is offline
Senior Member
 
Join Date: Mar 2014
Location: Florence,Ky.
Posts: 246
Default

I like the plan. I had a thought of putting more insulation in or hanging sound barriers up too. I think we need to hear a video of it to see what we are dealing with lol

  #4  
Old 12-08-2019, 04:38 PM
shaker455's Avatar
shaker455 shaker455 is offline
Ultimate Warrior
 
Join Date: Feb 2002
Location: NH
Posts: 4,471
Default

Quote:
Originally Posted by i82much View Post
I've got a 505 in my 65 GTO, 87 cc e-heads, dougs round ports, full Pypes exhaust with a 3" x pipe into 3", 20 inch long race pros, then tapers down to 2.5" tail pipes.

Right now I am just trying to make it a basic street car. When I idle the car in my shop at night, my wife says it can keep our 2 year old awake.

My current plan is to get rid of the 3" Race Pros and switch to 2.5" Dynomax Super Turbos, use the Flowmaster reducer cone in front of the muffler, and see if that makes a difference. Am I on the right track, or just a waste of money? I want the car to be as quiet as possible at idle.
I've found going from 2-1/2" to 3" will quite the car down.

Make another choice on mufflers.

But overall you can not quite HP.

__________________
Carburetor building & modification services
Servicing the Pontiac community over 20 years

Last edited by shaker455; 12-08-2019 at 04:49 PM.
  #5  
Old 12-08-2019, 04:41 PM
Steve C. Steve C. is offline
Ultimate Warrior
 
Join Date: Dec 1999
Location: Liberty Hill, Tx. (Austin)
Posts: 10,385
Default

Is there a SCFM flow rating for the 3" Race Pros for comparision to what DynoMax rates their muffler at, if so take note.

In the past I used to run only DynoMax UtraFlo Welded mufflers but on the previous 462 combo I went to their Super Turbo muffler because it was going to be street only and the HP loss was was not a factor (it made 580 hp). The Super Turbos are noticeably quieter. But now On my current 505 at about 650 hp I did not want to 'choke' it down and went back to the UltraFlow welded with far more flow than the super Turbos.

Current 505.
2-inch headers with full 3-inch exhaust including X-crossover and 3-inch tail pipes useing Ultra Flow Welded mufflers:
https://www.youtube.com/watch?v=sY76...ature=youtu.be

Sounds of DynoMaX

http://www.dynomax.com/sounds-of-dynomax/


.

__________________
'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE

Last edited by Steve C.; 12-08-2019 at 05:39 PM.
  #6  
Old 12-08-2019, 04:51 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

not too worried about losing power. i do not race it and i am pretty sure it will still rip my face off even with an exhaust change! just trying to get more time with the car and one of my issues is not wanting to start it after the kids go to bed.

  #7  
Old 12-08-2019, 04:55 PM
ta man ta man is offline
Ultimate Warrior
 
Join Date: Apr 2006
Location: Clinton,Ontario,Canada
Posts: 5,348
Default

It's hard to quiet big engines making 600 hp. The more you restrict the system with small pipes and mufflers you will lose power to the ground...maybe consider a "quiet system" but with cutouts.

__________________

466 Mike Voycey shortblock, 310cfm SD KRE heads, SD "OF 2.0 cam", torker 2
373 gears 3200 Continental Convertor
best et 10.679/127.5/1.533 60ft
308 gears best et 10.76/125.64/1.5471
  #8  
Old 12-08-2019, 04:55 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

Quote:
Originally Posted by Steve C. View Post
Is there a SCFM flow rating for the 3" Race Pros for comparision to what DynoMax rates their muffler at, if so take note.

In the past I used to run only DynoMax Utra Flo Welded mufflers but on the previous 462 combo I went to their Super Turbo muffler because it was going to be street only and the HP loss was was not a factor (it made 580 hp). The Super Turbos are noticeably quieter. But now On my current 505 at about 650 hp I did not want to 'choke' it down and went back to the UltraFlw welded with far more flow than the super Turbos.

Current 505.
2-inch headers with full 3-inch exhaust including X-crossover and 3-inch tail pipes useing Ultra Flow Welded mufflers:
https://www.youtube.com/watch?v=sY76...ature=youtu.be

Sounds of DynoMaX

http://www.dynomax.com/sounds-of-dynomax/


.
thanks steve. i plan to keep the race pros. right now doing an RPM, hyd roller lifters, mild springs, etc. But I have a port matched T2 and open spacer and some Isky solid roller bushing style lifters. Might go wilder in a few years when the kids get older. For now, quiet truck motor time!

  #9  
Old 12-08-2019, 04:56 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

Quote:
Originally Posted by ta man View Post
It's hard to quiet big engines making 600 hp. The more you restrict the system with small pipes and mufflers you will lose power to the ground...maybe consider a "quiet system" but with cutouts.
my x pipe has them, never uncapped. that’s what i should have done, ran it uncapped at first. then after the wife said something, put the race pros on and she would have been so happy about how quiet it was 😂

  #10  
Old 12-08-2019, 05:21 PM
slowbird's Avatar
slowbird slowbird is offline
Ultimate Warrior
 
Join Date: Jan 2001
Location: Montgomery, IL
Posts: 10,638
Default

I'd insulate the kids room for noise before touching the car. But that's me lol

  #11  
Old 12-08-2019, 05:21 PM
Formulajones's Avatar
Formulajones Formulajones is offline
Ultimate Warrior
 
Join Date: Jan 2012
Posts: 10,794
Default

Every time I've used the Race Pros I end up removing them. I've done that twice now on 2 different cars, so I don't waste anymore money there.

They have just been too loud everyplace for my taste. I end up with Dynomax these days pretty much like Steve has found.

  #12  
Old 12-08-2019, 05:35 PM
tom s tom s is offline
Ultimate Warrior
 
Join Date: Jan 2000
Location: long beach ca usa
Posts: 18,764
Default

Remember when you go to hyd rollers from solid rollers you will gain about 8 degrees of duration.Your idle if like mine will get more aggressive.I find the super turbos a little more quiet at idles but louder at 2000 cruise.My Hushpowers were more quiet at 2000 but were a little louder at idle.This was with 2 1/2 all the way back over the axles.Tom

  #13  
Old 12-08-2019, 06:28 PM
shoebox1.1 shoebox1.1 is offline
Senior Member
 
Join Date: Jun 2005
Location: mckinney texas
Posts: 189
Default

I had a SBC with full 3 inch duals with X pipe and dyno max super turbos 3 inch in and out. It was very reasonably quiet. About 480hp engine

__________________
GOD does business with people that mean business!
  #14  
Old 12-08-2019, 06:42 PM
TCSGTO's Avatar
TCSGTO TCSGTO is offline
Ultimate Warrior
 
Join Date: Dec 2000
Location: Warren,Ohio,USA
Posts: 1,675
Default

Try putting a Dynomax bullet muffler in each tailpipe. It would be quieter and no power loss.
https://www.summitracing.com/parts/wlk-24215/

__________________
68 GTO,3860#
Stock Original 400/M-20 Muncie,3.55’s
13.86 @ 100
Old combo:
462 10.75 CR,,SD 330CFM Round Port E's,Old Faithful cam,Jim Hand Continental,3.42's.
1968 Pontiac GTO : 11.114 @ 120.130 MPH

New combo:
517 MR-1,10.8 CR,SD 350CFM E's,QFT 950/Northwind,246/252 HR,9.5” 4000 stall,3.42's
636HP/654TQ
1.452 10.603 @ 125.09
http://www.dragtimes.com/Pontiac-GTO...lip-31594.html
  #15  
Old 12-08-2019, 06:59 PM
Scott Stoneburg's Avatar
Scott Stoneburg Scott Stoneburg is offline
Ultimate Warrior
 
Join Date: Sep 2007
Posts: 2,179
Default

*You have 3" pipe from the headers to the mufflers now?
Does this car have an X-pipe?
If so the I would go to a 2-1/2" Dynomax super turbo. As large a case as you can get.
How big is the cam?

  #16  
Old 12-08-2019, 07:36 PM
ponjohn's Avatar
ponjohn ponjohn is offline
Ultimate Warrior
 
Join Date: Mar 2002
Location: Connecticut
Posts: 9,530
Default

I can tell what not to choose, 40 series flowmaster. Ungodly loud.

  #17  
Old 12-08-2019, 07:39 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

Quote:
Originally Posted by ponjohn View Post
I can tell what not to choose, 40 series flowmaster. Ungodly loud.
i grew up in the 90’s. the word “flowmaster” immediately conjures up images of some vanilla ice looking dude pulling up next to my gto in his five point oh mustang and revvkng his engine while cranking the rap music and fixing his hair.

you don’t have to worry about me running flowmasters!!!!

  #18  
Old 12-08-2019, 07:41 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

Quote:
Originally Posted by Scott Stoneburg View Post
*You have 3" pipe from the headers to the mufflers now?
Does this car have an X-pipe?
If so the I would go to a 2-1/2" Dynomax super turbo. As large a case as you can get.
How big is the cam?
most specs in first post. 3” x pipe into mufflers and drops to 2.5 tailpipes after the mufflers. thinking of putting the reducers in front of the mufflers and running the 2.5” super turbos.

old faithful 1.0 and 1.5 rockers. baby cam!

  #19  
Old 12-08-2019, 07:42 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

Quote:
Originally Posted by TCSGTO View Post
Try putting a Dynomax bullet muffler in each tailpipe. It would be quieter and no power loss.
https://www.summitracing.com/parts/wlk-24215/
i will have to look. i have the side splitters so not sure the tailpipe has room? cool idea either way.

  #20  
Old 12-08-2019, 07:43 PM
i82much's Avatar
i82much i82much is offline
Ultimate Warrior
 
Join Date: Dec 2005
Posts: 2,786
Default

Quote:
Originally Posted by tom s View Post
Remember when you go to hyd rollers from solid rollers you will gain about 8 degrees of duration.Your idle if like mine will get more aggressive.I find the super turbos a little more quiet at idles but louder at 2000 cruise.My Hushpowers were more quiet at 2000 but were a little louder at idle.This was with 2 1/2 all the way back over the axles.Tom
i have the comp hyd lifters now. isky red zone solid bushing lifters in the shop somewhere, assuming i can still find them!

Reply

Thread Tools
Display Modes

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

Forum Jump


All times are GMT -4. The time now is 05:55 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017