Hedman LT's...y-pipe routing idea
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From: Hinesville, GA USA
Car: '86 IROC-Z/'94 Z28
Engine: 350 LT1/382 LT1
Transmission: 4L60-E/T-56
Axle/Gears: 3.45/3.42 (soon 4.10)
Hedman LT's...y-pipe routing idea
Since the longtube collectors are so short and my y-pipe is a POS, I am going to redo that portion of my exhaust to where it meets with the Borla. I know this isnt the best thing for power but maybe would work better for ground clearance and torque.
I am going to leave the passenger side header alone. The driver side header, I'm going to cut the flange off, weld a 90 directly on it, then weld the flange back on before it runs between the engine and trans, kind of like the factory routing. it'll run toward the passenger header, and before it gets there, turn right with another 90 or maybe 2 45's if I find room.they will run side by side towards the borla and I will use the orignal flange from the old cat to make it a bolt on deal. Might even make a 'mini' X or H before they merge into the borla to minimize the 'gurgle' some people get at certain RPM's from a single exhaust. Should be able to keep it nice and tight too (just how I like it
)
Think it would work? I know the first 90 isnt best for power, and yes I have the 02 bungs already welded on. I figured it might make for a cleaner install, and with the two pipes running parallel, it would make for less of an angle for the exhaust pulses to 'merge' into the intermediate pipe. This car is a driver with a LTR intake and an automatic so high RPM power isnt the idea here.
Too bad I cant do this with hooker LT's... the collector is too long. I have some exhaust tools left over from my true duals that I built for my '94 (which had GREAT clearance for a catted stainless 3" true dual setup on a lowered Z) Some ideas?
I am going to leave the passenger side header alone. The driver side header, I'm going to cut the flange off, weld a 90 directly on it, then weld the flange back on before it runs between the engine and trans, kind of like the factory routing. it'll run toward the passenger header, and before it gets there, turn right with another 90 or maybe 2 45's if I find room.they will run side by side towards the borla and I will use the orignal flange from the old cat to make it a bolt on deal. Might even make a 'mini' X or H before they merge into the borla to minimize the 'gurgle' some people get at certain RPM's from a single exhaust. Should be able to keep it nice and tight too (just how I like it
)Think it would work? I know the first 90 isnt best for power, and yes I have the 02 bungs already welded on. I figured it might make for a cleaner install, and with the two pipes running parallel, it would make for less of an angle for the exhaust pulses to 'merge' into the intermediate pipe. This car is a driver with a LTR intake and an automatic so high RPM power isnt the idea here.
Too bad I cant do this with hooker LT's... the collector is too long. I have some exhaust tools left over from my true duals that I built for my '94 (which had GREAT clearance for a catted stainless 3" true dual setup on a lowered Z) Some ideas?
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From: MA
Car: 1981 Chevy Malibu, 1987 Formula 350
Engine: 229 V6, L98 TPI 350
Transmission: TH350, 700R4
Axle/Gears: 10 bolt ???, 9 bolt 3.27 posi
Bump. I'm curious as well, I thought the samething while putting my Hedman long tubes in.
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From: Reno, NV
Car: 1982 Z28 & 1967 RR/SS 396
Engine: ZZ383 & 375hp 396
Transmission: T56 & factory TH400
Axle/Gears: 9" ford & 12 bolt 4.10
If you do it. Put up some pictures of it. Your right about the 90° at the end of the header for power. It will really slow down the flow on that side of the motor. It might also cause some tuning issues. You will have to wait and see. Curious to see how it all works out.
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
I think you're going to find that there's no room to run a pipe between the engine and transmission.
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From: Hinesville, GA USA
Car: '86 IROC-Z/'94 Z28
Engine: 350 LT1/382 LT1
Transmission: 4L60-E/T-56
Axle/Gears: 3.45/3.42 (soon 4.10)
We'll see how it goes. I'm gonna take a look at the ground clearance at the rear of the tranny with the car on the ground. it wouldnt cause too much of a restriction since it is 3" pipe and it doesnt really need it, and should get more backpressure downstream as the exhaust is cooling off when it hits the Y.
If I run it behind the trans, not only would that be a PITA, but it'll probably end up consisting of more of the same... at least one 90 and a couple 45's, probably 2 90's. Just like if it were in the front off the header collector.
I considered running 3" on that one side to the y, and 2 1/2 on the other to help equalize things, and run the 2 1/2 into the 3, but that seems kinda doofed up doesnt it? Just an idea.
As far as the routing goes, it would go in the factory y-pipe location. Only difference the pipe would have to be made more ovate where it passes between the two without hacking it up. Shouldnt be too horrifying. I'm more worried about the bends than running it that way.
If I run it behind the trans, not only would that be a PITA, but it'll probably end up consisting of more of the same... at least one 90 and a couple 45's, probably 2 90's. Just like if it were in the front off the header collector.
I considered running 3" on that one side to the y, and 2 1/2 on the other to help equalize things, and run the 2 1/2 into the 3, but that seems kinda doofed up doesnt it? Just an idea.
As far as the routing goes, it would go in the factory y-pipe location. Only difference the pipe would have to be made more ovate where it passes between the two without hacking it up. Shouldnt be too horrifying. I'm more worried about the bends than running it that way.
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Before you figure out how you're going to route the pipe, you need to get the headers installed, get the car up in the air and have a look underneath. What you're thinking of isn't going to happen.
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Joined: Sep 2006
Posts: 747
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From: Reno, NV
Car: 1982 Z28 & 1967 RR/SS 396
Engine: ZZ383 & 375hp 396
Transmission: T56 & factory TH400
Axle/Gears: 9" ford & 12 bolt 4.10
That might be able to be don with a "shorty header" but I agree that with a LT header it is not going to happen. Unless he is talking about doing it right in front of the transmission pan.
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From: Hinesville, GA USA
Car: '86 IROC-Z/'94 Z28
Engine: 350 LT1/382 LT1
Transmission: 4L60-E/T-56
Axle/Gears: 3.45/3.42 (soon 4.10)
Headers are installed as are the 02 bungs. I think it's doable but it'll take some time and crafty work to make it all fit well. I have a y on there now but it absolutely sucks on ground clearance and everything else. Not to mention it leaks and has been dented quite a few times.
It'll take header modification to fit, but I only have $80 in them so I'm not too worried about that.
I'll show you guys pics here in about a week or so.
It'll take header modification to fit, but I only have $80 in them so I'm not too worried about that.
I'll show you guys pics here in about a week or so.
Last edited by dhirocz; Feb 10, 2007 at 03:10 PM.
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