Replacing the Exhaust Manifold
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Replacing the Exhaust Manifold Hello!
My first post on LS1Tech.com! Hopefully my question will be clear:
I am a college student with a tight budget and rebuilding my 2000 Pontiac Trans Am. I have been working all summer and I have the engine out of the car, and down to the bare block. One of the things I would like to replace is the exhaust manifold. I was did a bit of research and decided on Shorties. ( for their torque benefits over Longtubes. If I am wrong please correct me). I also thought that they would be able to be bolted to the block and the catalytic converter without any alterations. BUT it seems like shorties are fairly expensive. ( remember, I am a broke college student lol) I have found some longtubes that are cheaper, but I am not sure how much of a pain it would be to put into the car. I've read alot of threads on this website about longtubes, and it seems that most of them fit pretty easily. However, no one has mentioned how the longtubes bolt up to the rest of the exhaust system. I understand that they will mount fine on the block, but will they be the proper length to tough the Y pipe? It will obviously remove the cataytic converter from the system, but how well it will bolt to the rest of the system is what prevents me from ordering them. Any advice guys?
(2000 Trans Am t-56 manual transmission)
My first post on LS1Tech.com! Hopefully my question will be clear:
I am a college student with a tight budget and rebuilding my 2000 Pontiac Trans Am. I have been working all summer and I have the engine out of the car, and down to the bare block. One of the things I would like to replace is the exhaust manifold. I was did a bit of research and decided on Shorties. ( for their torque benefits over Longtubes. If I am wrong please correct me). I also thought that they would be able to be bolted to the block and the catalytic converter without any alterations. BUT it seems like shorties are fairly expensive. ( remember, I am a broke college student lol) I have found some longtubes that are cheaper, but I am not sure how much of a pain it would be to put into the car. I've read alot of threads on this website about longtubes, and it seems that most of them fit pretty easily. However, no one has mentioned how the longtubes bolt up to the rest of the exhaust system. I understand that they will mount fine on the block, but will they be the proper length to tough the Y pipe? It will obviously remove the cataytic converter from the system, but how well it will bolt to the rest of the system is what prevents me from ordering them. Any advice guys?
(2000 Trans Am t-56 manual transmission)
Ahhhh I remember the college days. When I would ask for parts every Christmas to "help my gas mileage". 
DON'T waste money on shorties. I don't think any benefits they *might* offer will be worth the price of them. As for long tubes, you'll also need a few other things. It won't bolt up to the factory y pipe, but a new y pipe will allow you to bolt it to your existing catback. Sooo... A new Y pipe (catless in your case because they're way cheaper), poly motor mounts, longer 02 sensors, some quality clamps, and OEM multilayer steel exhaust manifold gaskets. It's more money, but that's doing it the right way. And while you have everything out, now is the time to do it! Put it off a little while to save up if need be. Look up Speed Engineering or Texas Speed long tubes. Quality stainless steel headers at a low price.
DON'T waste money on shorties. I don't think any benefits they *might* offer will be worth the price of them. As for long tubes, you'll also need a few other things. It won't bolt up to the factory y pipe, but a new y pipe will allow you to bolt it to your existing catback. Sooo... A new Y pipe (catless in your case because they're way cheaper), poly motor mounts, longer 02 sensors, some quality clamps, and OEM multilayer steel exhaust manifold gaskets. It's more money, but that's doing it the right way. And while you have everything out, now is the time to do it! Put it off a little while to save up if need be. Look up Speed Engineering or Texas Speed long tubes. Quality stainless steel headers at a low price. Thread Starter
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http://www.speed-engineering.com/sho...ion-pipes.html
If you click on that link, there is a 1 and 7/8th header and y pipe for 399.99. Would that be the one you guys recommend? Thank you for the help. Its comforting when others can provide some guidance!
If you click on that link, there is a 1 and 7/8th header and y pipe for 399.99. Would that be the one you guys recommend? Thank you for the help. Its comforting when others can provide some guidance!
The stock motor mounts are rubber and wear out over time. If you installed long tubes without changing them to the harder/more durable polyurethane ones, you'd risk your headers banging on the k-member when you're back on the road. It's one of those "might as well while I'm here" deals to prevent issues later on.
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Okay, I didn't know if it was for any other reason then the stock mounts getting old. Thank you for your help sawblade99z. I just hope that everything will line up as it should. What should I do since I lose 2 O2 sensor locations. ( unless the headers dont have any spots for them) Won't there be a check engine light on? Will my engine run too rich or lean?
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Okay, I didn't know if it was for any other reason then the stock mounts getting old. Thank you for your help sawblade99z. I just hope that everything will line up as it should. What should I do since I lose 2 O2 sensor locations. ( unless the headers dont have any spots for them) Won't there be a check engine light on? Will my engine run too rich or lean?
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I looked on GMpartsdirect and the O2 sensors are almost $50.00. I found some Denso O2 sensors on Amazon (Someone in a different thread on LS1tech said they were good). What do you think of these? I will paste the link below. (The person on here said that they will work in any of the 4 locations, but that doesn't make sense to me, where do you think these should go?)
I was planning on deleting the EGR anyway, so I'm happy that the headers will do it. I will definitely get a tune when the money becomes available.
One last question: Since I have an Amazon account I get shipping for free (it may be a college thing...). Anyway, I looked up those speed engineering headers and ypipe on the amazon search bar, and the 1-3/4 option showed up. (I was planning on getting the 1-7/8 from speed engineering directly, but they said it will take 6-8 weeks because they are out of stock. However, the 1-3/4 headers from them, offered by amazon, are available right now, and I will get free shipping with it. I don't know how much of a difference the two sized will make. they are pretty close together. Since I am pressed for time, I'm very tempted to buy the 1-3/4 from amazon. do you guys have any inputs?
I was planning on deleting the EGR anyway, so I'm happy that the headers will do it. I will definitely get a tune when the money becomes available.
One last question: Since I have an Amazon account I get shipping for free (it may be a college thing...). Anyway, I looked up those speed engineering headers and ypipe on the amazon search bar, and the 1-3/4 option showed up. (I was planning on getting the 1-7/8 from speed engineering directly, but they said it will take 6-8 weeks because they are out of stock. However, the 1-3/4 headers from them, offered by amazon, are available right now, and I will get free shipping with it. I don't know how much of a difference the two sized will make. they are pretty close together. Since I am pressed for time, I'm very tempted to buy the 1-3/4 from amazon. do you guys have any inputs?
Yeah that's a front sensor. You will need the extensions, but they are the correct stock replacements. Denso parts are good from my experience. I wouldn't be scared to use those.
As for the primary sizes, everyone will tell you to wait for the 1 7/8" because they make a little more power. If your modding will only consist of bolt ons, it will likely not be a noticeable difference between the two. The 1 3/4" would be fine in that case. But if you plan on doing heads/cam later on, Id hold out for the 1 7/8". More power potential. I bought a set of the 1 3/4", only for my build plans to change (read: get a lot more expensive) and now I'll have to buy a set of 1 7/8". Then sell the 1 3/4" for a loss. So figure out your end goal and then make this purchase accordingly. It's no fun having to buy parts or do the install twice.
As for the primary sizes, everyone will tell you to wait for the 1 7/8" because they make a little more power. If your modding will only consist of bolt ons, it will likely not be a noticeable difference between the two. The 1 3/4" would be fine in that case. But if you plan on doing heads/cam later on, Id hold out for the 1 7/8". More power potential. I bought a set of the 1 3/4", only for my build plans to change (read: get a lot more expensive) and now I'll have to buy a set of 1 7/8". Then sell the 1 3/4" for a loss. So figure out your end goal and then make this purchase accordingly. It's no fun having to buy parts or do the install twice.
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I don't think I will go that far in modifications. supercharging might be the only major thing I attempt. But that is a lot of money, and I wont even consider doing that for another few years. I think Ill go with the 1-3/4 because it will be sufficient in what future mods I do. (most likely bolt-ons)
Anything else I'm missing?
1) Speed Engineering Header and Y-Pipe (1-3/4)
2) Two Delco O2 sensors
3) Two O2 sensor Extensions
4) Tune w/ Downstream O2 sensor deletes, and EGR Delete
(what is an AIR system?)
Anything else I'm missing?
1) Speed Engineering Header and Y-Pipe (1-3/4)
2) Two Delco O2 sensors
3) Two O2 sensor Extensions
4) Tune w/ Downstream O2 sensor deletes, and EGR Delete
(what is an AIR system?)
Don't forget the poly motor mounts and GM exhaust manifold gaskets. The headers will come with some graphite ones. Don't use them. They can leak or blow out. Buy the stock multilayer steel ones. Other than that, you're golden.
The AIR system heats up the cats. Emissions crap. It will come off with the long tube install like the EGR. There's some piping running along the driver side of the engine bay that goes back behind the intake manifold and also down into the front bumper. The air pump is in the bumper. It makes that whistling noise you hear and then it goes away after a start up sometimes. You can strip all that junk out at the same time to clean up the engine bay some.
The AIR system heats up the cats. Emissions crap. It will come off with the long tube install like the EGR. There's some piping running along the driver side of the engine bay that goes back behind the intake manifold and also down into the front bumper. The air pump is in the bumper. It makes that whistling noise you hear and then it goes away after a start up sometimes. You can strip all that junk out at the same time to clean up the engine bay some.
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I'm in the same boat as you with the "while it's apart" I'm going to do the motor mounts. Mine are shot as the engine sags and shake the chassis more. If you replace them with stock brand new rubber ones are the long tubes going to be an issue still? I heard the poly ones send more vibrations through the chassis and I want it to be as smooth as possible since it's a daily driver.
I honestly don't know. Most of these cars are now higher mileage so that may be why it's common to suggest poly mounts as an all but required part for long tubes. I'd say for a while new stock ones would be fine. But years down the road you may be doing the job again. Some people say they didn't even notice more vibrations with the poly, others say it bothers them a lot. I'm doing them so I never have to worry about replacing them and doing it the hard way (engine in car).
Speed engineering 1 7/8" for sure. They make more power even on non head and cam setups.. Def do the poly mounts or you will regret it. The SE headers tuck up real tight and install very easily. As far as vibration with poly's. I barely notice it, if I bought the car that way I would never know the difference. If you didn't mention it run some msd 8.5mm wires and ngk tr55 plugs.