Intake with 85mm
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Joined: Feb 2018
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From: georgia
Intake with 85mm
From my understanding my 99 has a 78mm throttle body. Was thinking of adding an intake which has an 85mm opening. First question is it even worth it to go with an aftermarket intake with basically a stock engine? Second, if so, I would assume I would need a spacer/adapter-do they even make this? So far, I have not been able to locate this size. Thanks
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From: South Hill Wa
2022 C5 of the Year Finalist - Modified
2021 C5 of the Year Finalist - Modified
There is no such creature I am aware of with an 85mm opening. Even the LS6 manifold is still using a 78mm throttle body. On a stock engine I think you are just spending money kind of needlessly.
If you insist though I would just find a nice LS6 intake to put on the car but don't spend do much because there's not going to be a huge gain from it.
The next big jump would be a 90/92mm intake like a FAST or Dorman but that would require another couple hundred dollar 4 bolt throttle body and here again on a stock engine not really help your situation.
If you want to make some good honest seat of the pants power with your stock engine I strongly encourage putting on the best long tube headers you can afford and get it dyno tuned. Maybe even combine this with the LS6 intake.
If you insist though I would just find a nice LS6 intake to put on the car but don't spend do much because there's not going to be a huge gain from it.
The next big jump would be a 90/92mm intake like a FAST or Dorman but that would require another couple hundred dollar 4 bolt throttle body and here again on a stock engine not really help your situation.
If you want to make some good honest seat of the pants power with your stock engine I strongly encourage putting on the best long tube headers you can afford and get it dyno tuned. Maybe even combine this with the LS6 intake.
Thread Starter
Intermediate
Joined: Feb 2018
Posts: 45
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From: georgia
Makes sense. A buddy of mine has intake that he was going to use for a different project. He says it fits on the LS1 engine but is 85mm. I think I may end up going with the ls6 -seems the easiest and maybe pick up a few ponies. If I decide to go with the headers, do the cats have to come out? The car is in great shape and only has 52k on it, but i'm not sure it is worth dumping money into it unless I was really serious about adding hp...thanks for the advice!
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Joined: Aug 2018
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From: South Hill Wa
2022 C5 of the Year Finalist - Modified
2021 C5 of the Year Finalist - Modified
Nearly all of the brands of long tube headers out there have catted offerings.
And you are correct, it's a rabbit hole a lot of people get caught up in. You can fart around and spend a lot of money to make 10 horsepower and that's ok as long as you are enjoying it, or you can spend money on deeper mods and make really good power that is very noticeable. Like adding 100whp reliably. As they say, you have to pay to play. Only you can decide.
Sounds like you have a really nice car on your hands.
And you are correct, it's a rabbit hole a lot of people get caught up in. You can fart around and spend a lot of money to make 10 horsepower and that's ok as long as you are enjoying it, or you can spend money on deeper mods and make really good power that is very noticeable. Like adding 100whp reliably. As they say, you have to pay to play. Only you can decide.
Sounds like you have a really nice car on your hands.
