Deal and a half ! 
LS2 vs LS3 Throttle Body
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
What other MODs have you done to the engine. Just adding a FAST intake isnt going to give you all that much inprovement. You will also need a TUNER to recalibrate the MAF, adjust the airflow and some other stuff.
I have a FAST 90 Manifold and a LS2 90mm TB that I ported but, I also have ported heads, big cam LT Headers, 42 lb/hr injectors VARARAM and a tune.
You will need a LS1 to LS2 harness adaptor. I got mine from CASPER
I have a FAST 90 Manifold and a LS2 90mm TB that I ported but, I also have ported heads, big cam LT Headers, 42 lb/hr injectors VARARAM and a tune.
You will need a LS1 to LS2 harness adaptor. I got mine from CASPER
Le Mans Master
Joined: Sep 2003
Posts: 6,276
Likes: 226
From: Farmington CT
Cruise-In VII Veteran
best bet is to upgrade/re-pin the harness and use a 99 or 01up PCM
Do some research on the TB's; silver and gold blades, bottom or top flip, I believe 2008 was the year change IIRC to the top rotating forward
1. LS2/3/7
2. gold vs. silver blade
3. year
4. blade top opens which way
Get the answers, hopefully whoever you ordered the 102 from will help you
Do some research on the TB's; silver and gold blades, bottom or top flip, I believe 2008 was the year change IIRC to the top rotating forward
1. LS2/3/7
2. gold vs. silver blade
3. year
4. blade top opens which way
Get the answers, hopefully whoever you ordered the 102 from will help you
Thread Starter
5th Gear
Joined: Oct 2012
Posts: 5
Likes: 0
From: Memphis Tn
Thanks for the feed back. I do have a setup already almost exacly like yours Bill. All I lack is the cheaper 90ml TB so I can get it tuned and dialed in. Simply concerned about problem free functionality of an LS3 TB vs a good old LS2 TB. It seems the LS3 is more available in the marketplace!
Burning Brakes
Joined: Sep 2008
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From: Phoenix, AZ
Tech Contributor
Joined: Jan 2004
Posts: 20,030
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From: Wylie TX --> Less is More, except under the hood !
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Tech Contributor
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From: Wylie TX --> Less is More, except under the hood !
Drifting
Joined: Apr 2010
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From: Vetteville Tennessee
Once you have the adapter harness it's plug and play, then tune (at least on the late model C5's).
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
With the correct adapter wire harness, all your LS1 parts will plug right in.
HTH
Team Owner
Joined: May 2001
Posts: 36,836
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
The only caveat I would offer is in regard to that particular Caspers harness adapter. Look closely at the end view of the flat, six cavity connector and you'll see 2 open holes.
That connector uses a silicone weather resistent grommet just like all the other Weatherpack/Metri-Pak connectors so leaving those 2 unused cavities open to atmosphere (water/moisture/dust and possible corrosion) makes no sense whatsoever. I can't understand why Casper's does that, when all it takes is two "filler plugs" or a small glob (technical term) of silicone squeezed into them to seal the connector as the design intended in the first place.
Racetronix on the other hand doesn't cheap out and actually plugs those two unused holes (you can see them in their picture between the blue wire and the pink wire where they exit the connector body) and on top of that, the Racetronix harness is $5.00 cheaper in price than Casper's.
http://www.racetronix.biz/itemdesc.a...2DTBAH&eq=&Tp=
Tech Contributor
Joined: Jan 2004
Posts: 20,030
Likes: 289
From: Wylie TX --> Less is More, except under the hood !
Good info Mark and a sweet deal too.
The only caveat I would offer is in regard to that particular Caspers harness adapter. Look closely at the end view of the flat, six cavity connector and you'll see 2 open holes. That connector uses a silicone weather resistent grommet just like all the other Weatherpack/Metri-Pak connectors so leaving those 2 unused cavities open to atmosphere (water/moisture/dust and possible corrosion) makes no sense whatsoever.
I can't understand why Casper's does that, when all it takes is two "filler plugs" or a small glob (technical term) of silicone squeezed into them to seal the connector as the design intended in the first place.
Racetronix on the other hand doesn't cheap out and actually plugs those two unused holes (you can see them in their picture between the blue wire and the pink wire where they exit the connector body) and on top of that, the Racetronix harness is $5.00 cheaper in price than Casper's.
http://www.racetronix.biz/itemdesc.a...2DTBAH&eq=&Tp=
The only caveat I would offer is in regard to that particular Caspers harness adapter. Look closely at the end view of the flat, six cavity connector and you'll see 2 open holes.
That connector uses a silicone weather resistent grommet just like all the other Weatherpack/Metri-Pak connectors so leaving those 2 unused cavities open to atmosphere (water/moisture/dust and possible corrosion) makes no sense whatsoever. I can't understand why Casper's does that, when all it takes is two "filler plugs" or a small glob (technical term) of silicone squeezed into them to seal the connector as the design intended in the first place.
Racetronix on the other hand doesn't cheap out and actually plugs those two unused holes (you can see them in their picture between the blue wire and the pink wire where they exit the connector body) and on top of that, the Racetronix harness is $5.00 cheaper in price than Casper's.
http://www.racetronix.biz/itemdesc.a...2DTBAH&eq=&Tp=
Good info ! Thanks !
Toque
Thread Starter
5th Gear
Joined: Oct 2012
Posts: 5
Likes: 0
From: Memphis Tn
Thanks to everybody for the posts on this subject. Just wanted to let you know that I followed your advice and went to Racetronic for the harness, amazon for the TB, and Hinsonsupercars for the Fast102 40lb fuel inj, etc. Currently running 399 HP at rear wheels 11.2 in the qrtr, will let you know how all these addons work out! 
Melting Slicks
Joined: Nov 2009
Posts: 2,922
Likes: 219
From: West Branch, MI
Thanks to everybody for the posts on this subject. Just wanted to let you know that I followed your advice and went to Racetronic for the harness, amazon for the TB, and Hinsonsupercars for the Fast102 40lb fuel inj, etc. Currently running 399 HP at rear wheels 11.2 in the qrtr, will let you know how all these addons work out!
You're almost in the 10's! Might we inquire as to the full extent of your mods? The reason I'm asking as I'm fixing to do my engine mods in December and have virtually the same items as you except for the injectors. I'm also doing cam w/ PP/CNC'd heads as well and looking for 450rwhp. I'd also like to ask what tires you're using to hookup with and that seems to be the weakest link in our setups....getting that HP to the ground. Well done!!
Melting Slicks
Joined: Nov 2009
Posts: 2,922
Likes: 219
From: West Branch, MI
What other MODs have you done to the engine. Just adding a FAST intake isnt going to give you all that much inprovement. You will also need a TUNER to recalibrate the MAF, adjust the airflow and some other stuff.
I have a FAST 90 Manifold and a LS2 90mm TB that I ported but, I also have ported heads, big cam LT Headers, 42 lb/hr injectors VARARAM and a tune.
You will need a LS1 to LS2 harness adaptor. I got mine from CASPER
I have a FAST 90 Manifold and a LS2 90mm TB that I ported but, I also have ported heads, big cam LT Headers, 42 lb/hr injectors VARARAM and a tune.
You will need a LS1 to LS2 harness adaptor. I got mine from CASPER
I know many others have done this as well, but I want to publicly thank you for your expert help and assistance to the forum guys/gals here. You rock big time mi amigo!!
Advanced
Joined: Feb 2013
Posts: 77
Likes: 0
From: Fort Collins Colorado
So has anyone determined if the ls3 throttle body will work on the fast intake? I saw on amazon they're 375 for an ls2 and on Hinson supercars they have the ls3 for under 200 and it says the people that bought the ls3 throttle body also bought the adaptor for an ls1... Just curious because that's quite the price difference
Tech Contributor
Joined: Jan 2004
Posts: 20,030
Likes: 289
From: Wylie TX --> Less is More, except under the hood !
So has anyone determined if the ls3 throttle body will work on the fast intake? I saw on amazon they're 375 for an ls2 and on Hinson supercars they have the ls3 for under 200 and it says the people that bought the ls3 throttle body also bought the adaptor for an ls1... Just curious because that's quite the price difference
I got a new LS2 TB off Amazon 2 yrs ago for $201 shipped.
I wonder why the rise in cost ?
Toque
Advanced
Joined: Feb 2013
Posts: 77
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From: Fort Collins Colorado