Fast Intake Next Mod or LS3 Upper End?
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,548
Likes: 15
From: Paris TN
Fast Intake Next Mod or LS3 Upper End?
I've installed LG headers, hiflo cats and Xpipe as well as a Vararam CAI on my 06, LS2, 6 auto. I had Billy Boat axle backs but they were way too loud for my taste, so I'm back to stock axle backs. I would like to have a set of Corsa Touring axlebacks at some time, but I understand there's very little HP increase in that route compared to other possible mods and I don't happen to have an extra $1500 laying around for no HP gain.
My personal best has been 12.298@118 which is decent for what I've done. I was running 17" DRs as well. The MPH indicates great HP compared to some others on the fast list with similar mods.
I am thinking of the Fast intake, but don't know much about it. If I go with that bolt on, do I need a different throttlebody? If I need both, that's a pretty expensive mod. I understand the LS3 and LS2 Fast intakes are significantly different.
I've read elsewhere that an LS3 intake and upper end will make a significant HP improvement. Those intakes are relatively easy to come by used. What's all involved with that?
Some of you who have gone this route, please chime in with recommendations....thanks.
My personal best has been 12.298@118 which is decent for what I've done. I was running 17" DRs as well. The MPH indicates great HP compared to some others on the fast list with similar mods.
I am thinking of the Fast intake, but don't know much about it. If I go with that bolt on, do I need a different throttlebody? If I need both, that's a pretty expensive mod. I understand the LS3 and LS2 Fast intakes are significantly different.
I've read elsewhere that an LS3 intake and upper end will make a significant HP improvement. Those intakes are relatively easy to come by used. What's all involved with that?
Some of you who have gone this route, please chime in with recommendations....thanks.
Melting Slicks
Joined: Apr 2007
Posts: 2,987
Likes: 16
From: Phoenix
I would get a converter before getting a FAST. http://forums.corvetteforum.com/c6-t...-1-4-mile.html
Le Mans Master
Joined: Jan 2009
Posts: 5,656
Likes: 112
From: ocean springs mississippi
If you change to an ls3 top end (heads,intake),you will need to get new headers....cathedral port vs. rectangular port. I would go with the fast 102,you can use your stock throttlebody and have it ported....made a huge differance on mine.
Melting Slicks
Joined: Apr 2007
Posts: 2,987
Likes: 16
From: Phoenix
Here is a pic of the slight difference in exhaust ports between LS2/3/7.
http://www.pfadtracing.com/photos/sh...php/photo/2361
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
I've installed LG headers, hiflo cats and Xpipe as well as a Vararam CAI on my 06, LS2, 6 auto. I had Billy Boat axle backs but they were way too loud for my taste, so I'm back to stock axle backs. I would like to have a set of Corsa Touring axlebacks at some time, but I understand there's very little HP increase in that route compared to other possible mods and I don't happen to have an extra $1500 laying around for no HP gain.
My personal best has been 12.298@118 which is decent for what I've done. I was running 17" DRs as well. The MPH indicates great HP compared to some others on the fast list with similar mods.
I am thinking of the Fast intake, but don't know much about it. If I go with that bolt on, do I need a different throttlebody? If I need both, that's a pretty expensive mod. I understand the LS3 and LS2 Fast intakes are significantly different.
I've read elsewhere that an LS3 intake and upper end will make a significant HP improvement. Those intakes are relatively easy to come by used. What's all involved with that?
Some of you who have gone this route, please chime in with recommendations....thanks.
My personal best has been 12.298@118 which is decent for what I've done. I was running 17" DRs as well. The MPH indicates great HP compared to some others on the fast list with similar mods.
I am thinking of the Fast intake, but don't know much about it. If I go with that bolt on, do I need a different throttlebody? If I need both, that's a pretty expensive mod. I understand the LS3 and LS2 Fast intakes are significantly different.
I've read elsewhere that an LS3 intake and upper end will make a significant HP improvement. Those intakes are relatively easy to come by used. What's all involved with that?
Some of you who have gone this route, please chime in with recommendations....thanks.
Last edited by irok; Jan 27, 2013 at 04:52 PM.
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From: ocean springs mississippi
Burning Brakes
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I'm kicking around the same thing.....I think I'm rolling with the Fast & a nice stall. 
Glad to see you sold the Camaro and put yourself back in a real car!
Glad to see you sold the Camaro and put yourself back in a real car!
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Joined: Jan 2013
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From: Mooresville North Carolina
Since you have the car breathing well with a vararam and headers, my next move would be a torque converter (greatly cuts down e/t and gets you ready for a cam), followed by a cam, followed by heads, followed by a FAST mani if you're still feeling froggy.
Or, if the budget allows... supercharger!!
Or, if the budget allows... supercharger!!
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Le Mans Master
Joined: Jan 2009
Posts: 5,656
Likes: 112
From: ocean springs mississippi
Since you have the car breathing well with a vararam and headers, my next move would be a torque converter (greatly cuts down e/t and gets you ready for a cam), followed by a cam, followed by heads, followed by a FAST mani if you're still feeling froggy.
Or, if the budget allows... supercharger!!
Or, if the budget allows... supercharger!!
Melting Slicks
Joined: Apr 2007
Posts: 2,987
Likes: 16
From: Phoenix
Tech Contributor
Joined: Jul 2002
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From: St. Louis, MO
St. Jude Donor '08
Since you have the car breathing well with a vararam and headers, my next move would be a torque converter (greatly cuts down e/t and gets you ready for a cam), followed by a cam, followed by heads, followed by a FAST mani if you're still feeling froggy.
Or, if the budget allows... supercharger!!
Or, if the budget allows... supercharger!!
I have a thread showing these mods overlaid on the dyno sheet. They build upon each other.
http://forums.corvetteforum.com/c6-t...ast-heads.html
Last edited by Joe_G; Jan 27, 2013 at 08:46 PM.
Le Mans Master
Joined: Jan 2009
Posts: 5,656
Likes: 112
From: ocean springs mississippi
would you need to upgrade springs,rockers,pushrods,ect to run those cams? would like to go tfs 225's eventually or port the 243's...but $$$. will go s/c eventually,just need to go in stages.
Melting Slicks
Joined: Apr 2007
Posts: 2,987
Likes: 16
From: Phoenix
As far as springs go, that depends on ramp rate and lift whether you can run a good single or need dual springs. You can specify wanting to run a single spring and the cam can be designed around that. Pushrods will also need to happen. The .080" wall Comp pushrods are more than adequate.
If you are going to boost the motor eventually you need to be honest with yourself on how much boost you are going to run. Less than 10-12 psi and you will be okay with stock castings and an LS9 head gasket. Over that amount and I would recommend an aftermarket casting with a thick deck for better gasket seal.
Race Director
Joined: Sep 2007
Posts: 16,557
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Since your question was a FAST or LS3 heads, the order is the important part, assuming you'll eventurally do both.
If you do the LS3 heads first, then when you get ready for a FAST, you'll buy the one for the LS3 and have the stock LS3 manifold left over.
If you do the FAST first, then when you get ready for the heads, the choice becomes sticking with the LS2 FAST and reworking your LS2 heads, or going with LS3 heads and buying a new FAST.
The less expensive direction is the LS3 heads first. The downtime is also shorter, moreso if you decide to port the LS3 heads.
If you do the LS3 heads first, then when you get ready for a FAST, you'll buy the one for the LS3 and have the stock LS3 manifold left over.
If you do the FAST first, then when you get ready for the heads, the choice becomes sticking with the LS2 FAST and reworking your LS2 heads, or going with LS3 heads and buying a new FAST.
The less expensive direction is the LS3 heads first. The downtime is also shorter, moreso if you decide to port the LS3 heads.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,548
Likes: 15
From: Paris TN
you will pick up as much hp with the Fast 102 ported as you would going to the LS3 set up.a lot less work and you can use your tb. my car has run 3 tenths quicker than yours without the Fast on stock run flats. have not been to track since Fast installed but it did pick up 65 rwhp with Fast and headers.
I agree with this except I'd do the FAST on an ls2 before the heads. This is the order to mod a C6.
I have a thread showing these mods overlaid on the dyno sheet. They build upon each other.
http://forums.corvetteforum.com/c6-t...ast-heads.html
I have a thread showing these mods overlaid on the dyno sheet. They build upon each other.
http://forums.corvetteforum.com/c6-t...ast-heads.html
Since your question was a FAST or LS3 heads, the order is the important part, assuming you'll eventurally do both.
If you do the LS3 heads first, then when you get ready for a FAST, you'll buy the one for the LS3 and have the stock LS3 manifold left over.
If you do the FAST first, then when you get ready for the heads, the choice becomes sticking with the LS2 FAST and reworking your LS2 heads, or going with LS3 heads and buying a new FAST.
The less expensive direction is the LS3 heads first. The downtime is also shorter, moreso if you decide to port the LS3 heads.
If you do the LS3 heads first, then when you get ready for a FAST, you'll buy the one for the LS3 and have the stock LS3 manifold left over.
If you do the FAST first, then when you get ready for the heads, the choice becomes sticking with the LS2 FAST and reworking your LS2 heads, or going with LS3 heads and buying a new FAST.
The less expensive direction is the LS3 heads first. The downtime is also shorter, moreso if you decide to port the LS3 heads.
All of the comments are super helpful, thanks...now find me a reasonably priced used Fast LSXR!
Last edited by ParisTNDude; Jan 28, 2013 at 09:15 AM.
