Port and Polishing the Heads - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

cnjsanchez · 05-10-2010, 09:27 AM

I know there was a member on here that was doing this, but I can't seem to find it anymore. I was wondering what the final results where on this experiment, and how much it might cost? Also would it hurt anything if the heads outflowed the stock intake and exhaust manifolds?

John VS · 05-10-2010, 11:19 AM

We are all waiting. He has been on hold while his long tubes are shipped to him. Could be as early as this week.

Here's the thread: http://www.camaro5.com/forums/showthread.php?t=70647

2010 SSRS · 05-10-2010, 11:20 AM

cnjsanchez · 05-10-2010, 02:00 PM

Thanks for this. I'm thinking that I might go this way before adding some bolt-ons, since nobody is really getting huge numbers from them. I'm really thinking that the stock equipment might just perform pretty good if the heads were opened up.

bmwdon · 05-10-2010, 02:12 PM

you'd want to think about how well the engine dyno's are showing gains in the long tube headers through high flow cats already, so if stock heads are flowing that much better through a better header back exhaust, I wouldn't look to improve the heads flow rate through stock exhaust manifolds....just my opinion

I personally, if restricted to part at a time, would do headers/cats first, then some kind of better flowing cat back, then heads. I want to do it all at once, just waiting on the headers, then some available install time.

sorry...finding time anymore is a major pita.

Dr Jkel · 05-10-2010, 02:24 PM

I have heard from 3 different vendors that the gains, minimal, do not justify the cost of having this done. They say the stock heads flow really well

John VS · 05-10-2010, 03:39 PM

Quote:

They say the stock heads flow really well

Are you talking about V8 heads or V6 heads? This is a V6 thread...

cnjsanchez · 05-10-2010, 06:06 PM

Quote:

Originally Posted by bmwdon

you'd want to think about how well the engine dyno's are showing gains in the long tube headers through high flow cats already, so if stock heads are flowing that much better through a better header back exhaust, I wouldn't look to improve the heads flow rate through stock exhaust manifolds....just my opinion

I personally, if restricted to part at a time, would do headers/cats first, then some kind of better flowing cat back, then heads. I want to do it all at once, just waiting on the headers, then some available install time.

sorry...finding time anymore is a major pita.

Well I don't want it to be super loud. LT's will def make it too loud for me. I don't want a dragster. I like listening to music, and believe it or not I do like to talk to my wife while shes in there with me, and I know she won't get in there if it's way too loud. So do you think it'd be worth it to just port the heads or not?

John VS · 05-10-2010, 09:15 PM

Quote:

So do you think it'd be worth it to just port the heads or not?

The LLT has a stock exhaust to intake flow ratio of about 59%, which is already on the low side. Porting the heads without making a change to the exhaust will likely make this ratio lower. At some point performance is going to actually decline without some work on the exhaust.

I would consider the shorties first, then work on the heads. The sound of the shorties is not booming, so your wife would probably find it agreeable.

Anyway, that's my take. But if you do the heads, please let us know how it goes. I'm considering it myself.

cnjsanchez · 05-11-2010, 12:09 AM

I already have the MRT V2 axle back. IDK if that makes a difference though. I'm going to think about this awile. My next couple a mods will be to get it lowered and some different tires for my stock 18's.

bmwdon · 05-11-2010, 05:57 AM

I'd ask around the V6 area members that are running the shorties and see what their throughts are on sound/loudness. they are relatively inexpensive and I think Nallen was looking to make a matched up set of high flow cats. it's believed that it's primarily the stock cats that are a bit restrictive on the exhaust side.

but just my thinking is if you add more flow from the source without improving the ability for those gases to escape, you're going to cause more backup at the restriction....might not be right, but seems to make some sense.

I've got a high flow cat back system on the srt8, and it was a bit boomy on the highway and it resonated loudly at 18-1900 rpms, so I put down a layer of dynamat in the trunk floor and I'm good to go now, kids don't complain...and neither does the wife

Mankind · 05-11-2010, 06:50 AM

I put the JBA shorties on without changing the stock exhaust. Definately makes a difference in sound but it didn't raise the interior sound level. I later changed the mufflers and got a bit more sound under acceleration only. Even then the sound was pleasant under light accel. Only loud when you are 3/4 to WOT, pretty sure that is due to the muffler tho. Haven't heard any LT's in person but i keep being told they are louder in the cab even at regular driving speeds.

cnjsanchez · 05-11-2010, 08:43 AM

What you are saying does seem to make sense to me to. I will ask around, thanks for your input.

cnjsanchez · 05-11-2010, 08:44 AM

Looks like I might just have to go with the JBA shorties and some cats then.

05-10-2010, 09:27 AM	#1
cnjsanchez Drives: Camaro LS Join Date: Apr 2010 Location: BA, OK Posts: 75 View My Garage	Port and Polishing the Heads I know there was a member on here that was doing this, but I can't seem to find it anymore. I was wondering what the final results where on this experiment, and how much it might cost? Also would it hurt anything if the heads outflowed the stock intake and exhaust manifolds?

05-10-2010, 11:20 AM	#3
2010 SSRS Drives: 3 V8 Camaros Join Date: May 2009 Location: The Ocean State Posts: 111,187 View My Garage	__________________ Jannetty Racing JRE Street Package

05-10-2010, 02:12 PM	#5
bmwdon I refuse to go smurfy Drives: 2009 Challenger SRT8, 2010 Camaro Join Date: Nov 2009 Location: MD Posts: 1,311	you'd want to think about how well the engine dyno's are showing gains in the long tube headers through high flow cats already, so if stock heads are flowing that much better through a better header back exhaust, I wouldn't look to improve the heads flow rate through stock exhaust manifolds....just my opinion I personally, if restricted to part at a time, would do headers/cats first, then some kind of better flowing cat back, then heads. I want to do it all at once, just waiting on the headers, then some available install time. sorry...finding time anymore is a major pita. __________________ -Bill...the Camaro was my wifes, now she's got a minivan Challenger- 2009 Dodge Challenger SRT8 Procharger D1 Supercharger: 10.895 @ 126.720 MPH

05-11-2010, 05:57 AM	#11
bmwdon I refuse to go smurfy Drives: 2009 Challenger SRT8, 2010 Camaro Join Date: Nov 2009 Location: MD Posts: 1,311	I'd ask around the V6 area members that are running the shorties and see what their throughts are on sound/loudness. they are relatively inexpensive and I think Nallen was looking to make a matched up set of high flow cats. it's believed that it's primarily the stock cats that are a bit restrictive on the exhaust side. but just my thinking is if you add more flow from the source without improving the ability for those gases to escape, you're going to cause more backup at the restriction....might not be right, but seems to make some sense. I've got a high flow cat back system on the srt8, and it was a bit boomy on the highway and it resonated loudly at 18-1900 rpms, so I put down a layer of dynamat in the trunk floor and I'm good to go now, kids don't complain...and neither does the wife __________________ -Bill...the Camaro was my wifes, now she's got a minivan Challenger- 2009 Dodge Challenger SRT8 Procharger D1 Supercharger: 10.895 @ 126.720 MPH Last edited by bmwdon; 05-11-2010 at 07:32 AM.

05-10-2010, 11:19 AM	#2
John VS Drives: 2010 Camaro 2LT CGM, IOM Int. Join Date: Mar 2009 Location: Orange County, CA Posts: 381	We are all waiting. He has been on hold while his long tubes are shipped to him. Could be as early as this week. Here's the thread: http://www.camaro5.com/forums/showthread.php?t=70647

05-10-2010, 02:00 PM	#4
cnjsanchez Drives: Camaro LS Join Date: Apr 2010 Location: BA, OK Posts: 75 View My Garage	Thanks for this. I'm thinking that I might go this way before adding some bolt-ons, since nobody is really getting huge numbers from them. I'm really thinking that the stock equipment might just perform pretty good if the heads were opened up.

05-10-2010, 02:24 PM	#6
Dr Jkel and MR. HYDE Drives: 2010 2SS RJT/BLK 6Spd Man Join Date: May 2009 Location: Oxford, Alabama Posts: 4,375	I have heard from 3 different vendors that the gains, minimal, do not justify the cost of having this done. They say the stock heads flow really well

05-11-2010, 12:09 AM	#10
cnjsanchez Drives: Camaro LS Join Date: Apr 2010 Location: BA, OK Posts: 75 View My Garage	I already have the MRT V2 axle back. IDK if that makes a difference though. I'm going to think about this awile. My next couple a mods will be to get it lowered and some different tires for my stock 18's.

05-11-2010, 06:50 AM	#12
Mankind Whats a Millwright? Drives: 2LT/RS SIM, 05 Wht Denali Join Date: Feb 2010 Location: Holden, LA Posts: 410	I put the JBA shorties on without changing the stock exhaust. Definately makes a difference in sound but it didn't raise the interior sound level. I later changed the mufflers and got a bit more sound under acceleration only. Even then the sound was pleasant under light accel. Only loud when you are 3/4 to WOT, pretty sure that is due to the muffler tho. Haven't heard any LT's in person but i keep being told they are louder in the cab even at regular driving speeds.

05-11-2010, 08:43 AM	#13
cnjsanchez Drives: Camaro LS Join Date: Apr 2010 Location: BA, OK Posts: 75 View My Garage	What you are saying does seem to make sense to me to. I will ask around, thanks for your input.

05-11-2010, 08:44 AM	#14
cnjsanchez Drives: Camaro LS Join Date: Apr 2010 Location: BA, OK Posts: 75 View My Garage	Looks like I might just have to go with the JBA shorties and some cats then.