Is an LS6 a direct replacement for an LS1?

**cwk269** · 02-26-2010, 09:18 AM

I talked to my mechanic today about a rebuild and he told me he thought
I could buy an LS6 and it would be a direct replacement for the LS1 in my 99 Trans Am. He told me he didn't think any modification would be necessary and that I would have better results with it. Has anyone done this and is it a direct replacement as he suggest?

**Aetos** · 02-26-2010, 09:24 AM

It's not totally a direct replacement... the coolant lines are different for the LS6 intake... its a free fix though if you just sand the bottom of the ls6 intake, or you can buy the ls6 reroute kit

edit: also, gotta block off the EGR valve, but then you will throw codes if you don't get it tuned out.

**ICRAZY6** · 02-26-2010, 09:33 AM

Originally Posted by cwk269

I talked to my mechanic today about a rebuild and he told me he thought
I could buy an LS6 and it would be a direct replacement for the LS1 in my 99 Trans Am. He told me he didn't think any modification would be necessary and that I would have better results with it. Has anyone done this and is it a direct replacement as he suggest?

Are you talking about just the short block? It would be a direct replacement. All your parts on the ls1 will bolt right up to the LS6. If you get one with a cam already installed you would have to flash the ecu due to the cam differences.

**Aetos** · 02-26-2010, 09:38 AM

Originally Posted by ICRAZY6

Are you talking about just the short block? It would be a direct replacement. All your parts on the ls1 will bolt right up to the LS6. If you get one with a cam already installed you would have to flash the ecu due to the cam differences.

Oh wow, I'm an idiot.. I thought he was talking about ls6 intake... I just reread it...

**LSCyaL8R** · 02-26-2010, 11:04 AM

you should just get a whole crate LS6 if you are going that route. a nice 405hp base to start your car's new life from.

***SMWS6TA*** · 02-26-2010, 11:22 AM

You need to talk with SPAZ. I know he has an LS6 in his T/A.

**LSCyaL8R** · 02-26-2010, 12:06 PM

I just posted this in another thread but GMPP has some WICKED amazing prices on LS6's at the moment. could be a typo by the dealer but they are selling a complete LS6 brand new crate engine for 3,200.... if you have the coin you can get an LS7 for something like 8,500 or something.

**ws6rose** · 02-27-2010, 12:47 AM

Originally Posted by LSCyaL8R

I just posted this in another thread but GMPP has some WICKED amazing prices on LS6's at the moment. could be a typo by the dealer but they are selling a complete LS6 brand new crate engine for 3,200.... if you have the coin you can get an LS7 for something like 8,500 or something.

3,200, I might have to grenade my motor this weekend!

**00z28bubba** · 02-27-2010, 02:15 AM

direct swap. just need a touch up on the tune. no differences that would cause problems with install. the heads and cam are better and the reason the tune is needed.

**Aetos** · 02-27-2010, 06:39 AM

Is there really a point in spending the money for an LS6 if you already have a decent LS1? Isn't it better to spend the money on a 402/408 or something? If I'm not mistaking, aren't the limitations on the LS1/LS6 nearly identical?

**00z28bubba** · 02-27-2010, 12:31 PM

i would have suggested the same but timeframe and budget werent specified and i assumed he needed a quick fix.

**cwk269** · 02-28-2010, 01:26 AM

I don't have the coin for a LS7 so I was exploring my options and with this site and all of the knowledge posted on these forums, I figured to get some good advice. Thanks.....

**02transamce** · 02-28-2010, 04:56 AM

http://www.crateenginedepot.com/stor...-P1625C63.aspx

this. but since you have a 99 t/a you will have to get a ls6 intake as well.your other option is: http://www.crateenginedepot.com/stor...268-P10C0.aspx

now since it is for a cts you will have to swap your oil pan on or buy a new t/a oil pan but pretty much a direct swap,check out gm high tech performance magazine,in the latest issue (april 2010) they are putting a ls6 into a 00 camaro and they explaing what is needed for a cts ls6 crate motor swap into a f-body.

**9T8W66** · 02-28-2010, 06:00 AM

Originally Posted by 02transamce

http://www.crateenginedepot.com/stor...-P1625C63.aspx

this. but since you have a 99 t/a you will have to get a ls6 intake as well.your other option is: http://www.crateenginedepot.com/stor...268-P10C0.aspx

now since it is for a cts you will have to swap your oil pan on or buy a new t/a oil pan but pretty much a direct swap,check out gm high tech performance magazine,in the latest issue (april 2010) they are putting a ls6 into a 00 camaro and they explaing what is needed for a cts ls6 crate motor swap into a f-body.

Top link is the route I would go, simple swap of accesssories and oilpan then just pick up an LS6 intake.
IIRC the knock sensors require a different type of connector then LS1's but it's a simple fix. Also like mentioned above the EGR would need to be deleted from the engine bay and the ECM. The LS6 will run fine on the stock LS1 tune but would require a new tune to get the most out of it.
Also a great time to do a Cam upgrade with matched springs and headers.

**Aetos** · 02-28-2010, 06:26 AM

Originally Posted by cwk269

I don't have the coin for a LS7 so I was exploring my options and with this site and all of the knowledge posted on these forums, I figured to get some good advice. Thanks.....

The ls7/ls6 aren't your only options, you can get a built 402/408 lsx block.

If you have the time, try contacting texas-speed.com they can help you out.