3" Exhaust pics, please!!!
Thread Starter
Pro
Joined: Feb 2004
Posts: 564
Likes: 0
From: Pittsburgh PA
3" Exhaust pics, please!!!
Hey, all. I'm at the point where I need to start building a decent exhaust system on my bruiser.
The engine should be generating somewhere north of 600HP, 575 lbs.-ft of torque... Supercharged 427 BBC. I've got Hedman Husler headers on it, 2" primaries with 3 1/2" collectors. The current exhaust system (left-over from BUBBA
) goes from 2 1/2" to 2" and back... TWICE. 
It's a MESS, and I know it won't flow worth a darn...
But there's 3" flowmasters welded in at the back (go figure)... Since the flowmasters are SERIOUSLY welded, I'm debating whether to simply trash these, and go with something else... But I have firmly decided to run a 3" system all the way back, and not go for sidepipes...
So, exhaust gurus... Suggestions, please...? And perhaps pics? I would like to achieve maximum ground-clearance, and have the exhaust end at the (approximately) stock location...
Performance goals are simply to achieve the MOST I can with this engine, without being so obnoxious that the local PD pulls me over...
THANKS!!!
Eric
The engine should be generating somewhere north of 600HP, 575 lbs.-ft of torque... Supercharged 427 BBC. I've got Hedman Husler headers on it, 2" primaries with 3 1/2" collectors. The current exhaust system (left-over from BUBBA
) goes from 2 1/2" to 2" and back... TWICE. It's a MESS, and I know it won't flow worth a darn... But there's 3" flowmasters welded in at the back (go figure)... Since the flowmasters are SERIOUSLY welded, I'm debating whether to simply trash these, and go with something else... But I have firmly decided to run a 3" system all the way back, and not go for sidepipes...
So, exhaust gurus... Suggestions, please...? And perhaps pics? I would like to achieve maximum ground-clearance, and have the exhaust end at the (approximately) stock location...
Performance goals are simply to achieve the MOST I can with this engine, without being so obnoxious that the local PD pulls me over...
THANKS!!!
Eric
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
I had a hard time finding anyone who would install a 3" exhaust and guarantee that it wouldn't eventually rattle against the frame on the pass through holes (they must not be as good as the exhaust people who have installed the systems seen on this forum). I used this as an excuse to get the 3" side exhaust pipes that I really wanted anyway. 
If you want photos, I can give you some.
If you want photos, I can give you some.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
I don't have pictures here at work but I do at home. I didn't try to go through my transmission cross member. I modified it to run underneath or actually 1/2 through the bottom of the crossmember and outboard from the stock holes.
I also bought stainless elbows and cut and welded the exhuast together.
3inch is overkill and louder then a smaller 2 1/2 inch system.
I will try to post some pictures this evening.
I also installed cats for the visual inspection you can get on the roadside.
I also bought stainless elbows and cut and welded the exhuast together.
3inch is overkill and louder then a smaller 2 1/2 inch system.
I will try to post some pictures this evening.
I also installed cats for the visual inspection you can get on the roadside.
Racer
Joined: Apr 2005
Posts: 423
Likes: 20
From: Ontario
Originally Posted by norvalwilhelm
I also installed cats for the visual inspection you can get on the roadside.
Norval, do we really need cats for our area on the 75' since we're exempt from doing emissions every 2 years? Could we be forced to provide an emission test should the ministry feel the need.
Sorry I forgot I wasn't on my pc, it's
"Maymyvetteliveforevr"
Frank
Pro
Joined: Nov 2004
Posts: 677
Likes: 0
From: Frisco TX
On my 76 I have chambered exhaust and it's great. It was there from the prev owner. On the 89 I have 3" pipes... They sound great with the Flowmaster 40s on it. And then there is the other way to run them...
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Originally Posted by Mickman
Norval, do we really need cats for our area on the 75' since we're exempt from doing emissions every 2 years? Could we be forced to provide an emission test should the ministry feel the need.
Sorry I forgot I wasn't on my pc, it's
"Maymyvetteliveforevr"
Frank
Sorry I forgot I wasn't on my pc, it's
"Maymyvetteliveforevr"
Frank
They have printouts of our cars equipment and your car had better have cats if factory installed them.
It is a $450 fine for no cats and if a cop looks under and sees no cats you can't argue. It is cheaper to buy a pair of high flow cats and have them installed then it is to pay a fine and you have no arguement to use.
Yes a 75 needs cats.
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Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
This is my 3 inch stainless exhaust . It is pieced together and tig welded together.
This shows the modified crossmember
This shows the mandrel bent pieces that pass under the rear end.
This shows a overall shot of the 3 inch exhaust. It is tucked nice a tight to the floor boards.
This shows the modified crossmember
This shows the mandrel bent pieces that pass under the rear end.
This shows a overall shot of the 3 inch exhaust. It is tucked nice a tight to the floor boards.
Thread Starter
Pro
Joined: Feb 2004
Posts: 564
Likes: 0
From: Pittsburgh PA
Some COOL systems!!! 
Norval, nice work on your setup. I confess my little MIG (with flux-core wire) won't look as sexy as yours... But with a little practice (and grinder), who knows...?
I do wonder why you say the 3" is overkill, at my horsepower levels. Essentially, I'm running a milder (read that as CHEAPER) version of your engine.... Did you not see significant gains, by going to the 3" system? I admit, this makes me curious... Of course, if the 2 1/2" will do an equal job, then I could buy a pre-bent kit, and adapt it to my car without a lot of the headaches that a 3" system will bring...
Weeelllllllll... Besides having a 6" tall hood "blister" to cover everything except the bug-catcher on top of the engine, I'm hoping to be as mellow as possible... I mean, the car's gonna' be a cop-magnet... Just trying to not stick 'em in the eye too much (or should that be ear?)...
Norval, nice work on your setup. I confess my little MIG (with flux-core wire) won't look as sexy as yours... But with a little practice (and grinder), who knows...?
I do wonder why you say the 3" is overkill, at my horsepower levels. Essentially, I'm running a milder (read that as CHEAPER) version of your engine.... Did you not see significant gains, by going to the 3" system? I admit, this makes me curious... Of course, if the 2 1/2" will do an equal job, then I could buy a pre-bent kit, and adapt it to my car without a lot of the headaches that a 3" system will bring...
Originally Posted by big_g
I think that horse is already out of the barn...
Besides having a 6" tall hood "blister" to cover everything except the bug-catcher on top of the engine, I'm hoping to be as mellow as possible... I mean, the car's gonna' be a cop-magnet... Just trying to not stick 'em in the eye too much (or should that be ear?)...
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
I never compared a 2 1/2 inch to a 3 inch. I jumped all at once with the motor and the exhuast.
3 inch is louder no matter what you do and it is harder to run because of the diameter but it can be done if you take you time.
Flux core wire is never as easy to work with as solid wire and gas.
With the blower you don't need to worry about proper size pipe to engine size. You just need something big to move the spent gas.
Intake port flow, header size and exhuast are critical to a normal aspirated engine but not to a blower motor.
Even the cam within reason is not as critical.
3 inch is louder no matter what you do and it is harder to run because of the diameter but it can be done if you take you time.
Flux core wire is never as easy to work with as solid wire and gas.
With the blower you don't need to worry about proper size pipe to engine size. You just need something big to move the spent gas.
Intake port flow, header size and exhuast are critical to a normal aspirated engine but not to a blower motor.
Even the cam within reason is not as critical.
Last edited by norvalwilhelm; Jan 26, 2006 at 09:39 AM.
Thread Starter
Pro
Joined: Feb 2004
Posts: 564
Likes: 0
From: Pittsburgh PA
Originally Posted by norvalwilhelm
I never compared a 2 1/2 inch to a 3 inch. I jumped all at once with the motor and the exhuast.
3 inch is louder no matter what you do and it is harder to run because of the diameter but it can be done if you take you time.
Flux core wire is never as easy to work with as solid wire and gas.
3 inch is louder no matter what you do and it is harder to run because of the diameter but it can be done if you take you time.
Flux core wire is never as easy to work with as solid wire and gas.
Originally Posted by norvalwilhelm
With the blower you don't need to worry about proper size pipe to engine size. You just need something big to move the spent gas.
Intake port flow, header size and exhuast are critical to a normal aspirated engine but not to a blower motor.
Even the cam within reason is not as critical.
Intake port flow, header size and exhuast are critical to a normal aspirated engine but not to a blower motor.
Even the cam within reason is not as critical.
Any guesses, or heard of any studies on this?
